Tesis: "Bioplastic"

1

Kaidaniuk, Denys. "Starch bioplastic production". Thesis, National Aviation University, 2021. https://er.nau.edu.ua/handle/NAU/50627.

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1. Tang H., Ando H., Watanabe K. et al. Fine structures of amylose and amylopectin from large, medium and small waxy barley starch granules. Cereal Chemistry. 2001. Vol. 78. P. 111–115.
Plastic production is a necessity for humanity today. It is impossible to imagine an industry without it, whether it is the production of children's toys or the production of test tubes. However, the issue of environmental pollution is growing in direct proportion to the increase in plastic production. For example, mankind has created about 380 tons of plastic in 2018, of which only a small part was disposed of. Therefore, the issue of alternatives to plastics that are tolerant of the environment and human health is only gaining momentum. The main task of this work is to create a viable bioplastic from starch that can compete in the market with the usual sample. In fact, starch has long been used in this industry, this polysaccharide is a successful raw material for plastic production due to its properties, which are provided by its components: amylase and amylopectin, amylase in turn responsible for stickiness and water absorption, and amylopectin for strength. Виробництво пластику - це необхідність для людства сьогодні. Неможливо уявити собі індустрію без нього, незалежно від того, чи є це виробництво дитячих іграшок чи виробництво пробірок. Однак питання забруднення навколишнього середовища зростає прямо пропорційно збільшенню виробництва пластмас. Наприклад, людство виробило близько 380 тонн пластмаси у 2018 році, з якої була використана лише невелика частина. Тому питання альтернатив пластмас, які є толерантними до навколишнього середовища та здоров'я людини, отримує лише імпульс. Основним завданням цієї роботи є створення стійкого біопластику з крохмалю, який може конкурувати на ринку зі звичайним зразком. Фактично, крохмаль давно використовується в цій галузі, цей полісахарид є успішною сировиною для виробництва пластмас завдяки своїм властивостям, які забезпечуються його компонентами: амілаза та амілопектин, амілаза, яка відповідає за липкість та поглинання води, а також амілопектин для міцності.

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2

Sundin, Anton. "Produktion av bioplast i Värmland? : Fermentering av olika avfallströmmar". Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-36624.

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Ett av världens största miljöproblem är plastnedskräpning. På många platser kan spår av mänsklig närvaro ses i form av skräp av plast. År 2011 tillverkades det 280 miljoner ton plast, det motsvarar ungefär 28 000 Eiffeltorn. I Sverige förbrukades år 2010 ungefär 880 000 ton plast. I Asien produceras ungefär 50 % av all världens plast och Kina står för cirka hälften av detta. Nordamerika och Europa står för cirka 40 % av världens plastproduktion. Resterande produktion av plast är fördelat på Afrika och Sydamerika. Kommersiell plast är uppbyggd av små enheter kallade polymerer. Polymerer är i sin tur uppbyggda av ännu mindre enheter som kallas monomerer. Dessa monomerer är i dagsläget framställda av petroleum (råolja/mineralolja). Ungefär 4 % av världens oljekonsumtion går åt som råvara till att producera plast och lika mycket olja används som bränsle i tillverkningsprocessen. Begreppet bioplast är en hel familj av material som är biologiskt nedbrytbar, biobaserade eller bådadera. Det är dock inte en självklarhet att bioplaster besitter båda egenskaperna. PHA-plast är biobaserad och biologisk nedbrytbar, vilket är anledningen till att den står i fokus under detta examensarbete. För produktion av PHA-plast används en trestegsprocess, vilket innefattar ett fermenteringssteg, ett selektionssteg och ett ackumuleringssteg. Sist sker en extraktion för att frigöra PHA- plasten från det övriga organiska materialet. Syftet med det här examensarbetet är att med hjälp av framställning av bioplast främja miljön, vilket en anläggning som producerar bioplast skulle göra eftersom en del av den fossiloljebaserade plasten skulle kunna bytas ut mot bioplasten PHA. Större framställningsmöjligheter av bioplast i Värmland skulle medföra ett ökat intresse av en produktionsanläggning. Målet är att inventera olika industrier runt om i Värmland, i första hand matindustrier och skogsindustrier, och utreda deras processavloppsvattens potential att producera VFA. I detta examensarbete har fermenteringsförsök genomförts satsvis på processavloppsvatten från OLW, Barilla (Wasa), Skoghall, Gruvön och Rottneros. Försöken visar deras potential att producera VFA. Experimenten utfördes med ett konstant pH på 6 och varierande uppehållstid. Resultaten visade att OLW och Barilla har bäst potential till VFA-produktion med 4500 mg/l respektive 1610 mg/l. Spädning av OLWs och Barillas processavloppsvatten visade sig vara en gynnsam åtgärd, då VFA-produktionen ökade snabbare i jämförelse med de tester som utfördes vid icke-spädning. Dock erhölls inte lika stor totalmängd av VFA. Det är dock bättre att producera en större mängd VFA och på så vis låta processen ta längre tid. Vid fortsatta experiment rekommenderas att göra ytterligare försök på OLW och Barillas processavloppsvatten då de visade bäst potential till VFA-produktion.
One of the biggest environmental problems is the plastic littering. In many places traces of human presence is seen in the form of plastic littering. In the year 2011, 280 million tons of plastic was produced, which represents about 28 000 Eiffel Towers. In Sweden, about 880 000 tons of plastic a year is consumed, according to figures from 2010. Approximately 50 % of all the world's plastics are produced In Asia and China accounts for about half of it. North America and Europe account for about 40% of the world's plastic production. The remaining production is distributed between Africa and South America. Commercial plastic is made from small units called polymers. A polymer consists of smaller units called monomers. In present, these monomers are produced out of petroleum (crude oil/ mineral oil). Approximately 4% of the world’s oil consumption is spent as raw material to produce plastic and the same amount of oil is used as fuel in the plastic production process. The term bio-plastic is used for a family of materials which are biodegradable, bio- based or both. However, it is not given that bioplastics do possess both properties. PHA plastics are both bio based and biodegradable, which is why it is the focus for this thesis. Production of PHA plastic is a three-step process comprising a fermentation step, a selection step, and an accumulation stage. Finally, there is an extraction to release the PHA plastic from the organic material. The aim of this thesis is to aid the production of bioplastics in order to lessen the environmental load of plastics. The more bioplastic that can be produced, the greater the interest of a bioplastic-producing plant in Värmland. The goal is to make an inventory of industries around Värmland, primarily food industries and forest industries, and to quantify the potential of their process wastewaters to produce VFA. In this thesis, fermentation experiments conducted batch-wise was performed with process wastewater from OLW, Barilla (Wasa), Skoghall, Gruvön and Rottneros. The experiments showed the wastewaters potential to produce VFA. The experiments were performed with a constant pH of 6 and with varying residence time. The results showed that OLW and Barilla has the highest potential for VFA production with 4500 mg/l and 1610 mg/l, respectively. Dilution of OLWs and Barillas process water turned out to be favorable, as the VFA production increased rapidly in comparison with those tests that were conducted under non-dilution. The total production of VFA, however, was not as high. In further experiments, it is recommended to make another attempt at the OLWs and Barillas process wastewater since they showed the best potential for VFA production.

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Maryniaka, K. "Modern step into future: bioplastic". Thesis, Молодіжна наукова ліга, 2020. https://er.knutd.edu.ua/handle/123456789/16771.

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Modern chemistry has reached the level of molecular research, which made it possible to reveal the mechanisms of many processes in a living organism, synthesize substances that do not exist in nature, and decipher the genetic mechanisms of heredity. The development of the production of both biologically derived and biodegradable polymers cannot be stopped. Nowadays biopolymers in many areas represent a serious alternative to traditional polymeric materials. The notion that they are not competitive will not hold out for a long time. What is more, they certainly will not become a panacea for all environmental problems. The concept of biopolymers as 100% resource conserving agents is also premature. However, they open up new prospects in the post-oil era.

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4

Johnsson, Nathalie y Fredrik Steuer. "Bioplastic material from microalgae : Extraction of starch and PHA from microalgae to create a bioplastic material". Thesis, KTH, Materialvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231508.

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Microalgae used in sewers to capture CO2 eventually turns into waste material. Through the use oftheir biomass, the waste algae can be given a new purpose. In this study attempts to extract starch or PHA from three different algae; Calothrix Scytonemicola, Scenedesmus Almeriensis and Neochloris Oleoabundans, were made. We also attempted to create a bio-based plastic material. Both Scenedesmus Almeriensis and Neochloris Oleoabundans are starch rich microalga. By washing with acetone, cryo grinding, use of ultrasonic homogenizer and dialysis, starch was likely extracted successfully. The extracted material and the plasticiser Carboxymethyl Cellulose (CMC) was used to cast plastic film. The cast film was very thin and brittle; perhaps by using different plasticisers or additives a more usable bio-based plastic material can be created. The PHA rich algae Calothrix Scytonemicola was used to extract PHA. The algae was washed with acetone, cryo grinded and then mixed with Sodium Hypochlorite(aq) and deionised water to extract the desired PHA. Due to a shortage of algae very small amounts of material could be extracted. Therefore, the casting of a plastic film was performed with commercial PH3B, which is a type of PHA. Three attempts were conducted. The first one with only chloroform, the second one with CMC and chloroform and the last one with Sucrose Octaacetate and chloroform. The film with Sucrose Octaacetate gave the best plastic material in regards to mechanical properties.
Mikroalger som används i kloaker för att binda CO2 blir till slut restavfall. Genom att använda dess biomassa kan restalgerna få ett nytt syfte. I denna studie utfördes extraktionsförsök av stärkelse samt PHA från tre olika alger, Calothrix Scytonemicola, Scenedesmus Almeriensis och Neochloris Oleoabundans. Ytterligare försök genomfördes för att försöka framställa ett biobaserat plastmaterial. Både Scenedesmus Almeriensis och Neochloris Oleoabundans är stärkelserika mikroalger. Genom att tvätta dem med aceton, kryomalning, användning av en ultrasonic homogenizer och dialys kunde stärkelse troligtvis extraheras. Det extraherade materialet blandades med karboxymetylcellulosa (CMC) för att skapa en plastfilm. Filmen blev väldigt tunn och spröd, således behövs antingen en annat mjukningsmedel eller tillägg av additiv för att skapa ett mer användningsbart biobaserat plastmaterial. Den PHA-rika algen Calothrix Scytonemicola användes vid extraktionen av PHA. Algerna tvättades med aceton och kryomaldes innan PHA förhoppningsvis extraheras med hjälp av natriumhypoklorit(aq) och avjonat vatten. På grund av en för liten mängd tillgänglig alg extraherades endast en liten mängd material. Det var därför inte möjligt att skapa en plastfilm av vårt extrakt utan istället användes kommersiell PH3B, som är en typ av PHA. Tre försök genomfördes, en med endast kloroform, en med CMC och kloroform och den sista med sucrose octaacetate och kloroform. Den sistnämnda filmen gav det bästa plastmaterialet med avseende på de mekaniska egenskaperna.

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5

Helgeson, Matthew Steven. "Horticultural evaluation of zein-based bioplastic containers". [Ames, Iowa : Iowa State University], 2009.

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6

MONGILI, BEATRICE. "Biotechnological approches for green-based bioplastic production". Doctoral thesis, Politecnico di Torino, 2020. http://hdl.handle.net/11583/2836776.

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7

Bhardwaj, Rahul. "Modification of polylactide bioplastic using hyperbranched polymer based nanostructures". Diss., Connect to online resource - MSU authorized users, 2008.

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8

Klinke, Stefan. "Production of bioplastic in recombinant bacteria : from basic research to application /". [S.l.] : [s.n.], 1999. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=13448.

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9

Muppidi, Mahanand. "Toward libraries for increased bio plastic production in cyanobacteria". Thesis, KTH, Skolan för bioteknologi (BIO), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-173649.

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Cyanobateria are promising cell factories due to their minimal nutrient requirements and utilization of asmospheric carbon di-oxide as its sole carbon source. In particular, polyhydroxybutyrate (PHB) is an industrially useful bio plastic that is produced naturally by some cyanobacteria. Furthermore, PHB biosynthetic pathway is a starting point for production of the biofuel, 1-butanol. There has been much genetic engineering effort toward increasing the production of PHB from cyanobacteria. These have been focused on increasing the pool of acetyl-CoA precursor, or increasing the amount of the reductant NADPH. The upstream process for increasing these reactants is complex and involves many genes. In this contect, cyanobacteria libraries will contribute to reveal genes or gene fragments that are responsible for production of PHB, alkanes and other high value compounds. In pursuit of finding these novel genes or genefragments, a transcription factor library is created in this study with 50 transcription factors. Furthermore, the process is optimized towards the creation of genomic fragment library and metagenomic fragment library with 26 diverse strains. Membersof the transcription factor library are over-expressed by a PHB - producing host Synechocystis PCC 6803 and the process towards creation of genomic and metagenomic libraries is optimized. The members of the metagenomic library can be screened for increased PHB, alkanes, lactate and other high value products and the potential members can be isolated and characterized.

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10

Sundäng, Peters Emil. "Bioplastics from food waste liquid fraction". Thesis, KTH, Skolan för bioteknologi (BIO), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215036.

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11

Westerlund, Viktor. "Bioplastics from the food waste liquid fraction". Thesis, KTH, Skolan för bioteknologi (BIO), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215038.

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12

Zhao, Xiaoying. "Natural Rubber Toughened Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) Bioplastic for Food Packaging Applications". The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu154344332353769.

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13

Zhao, Lei. "Novel bio-composites based on whole utilisation of wheat straw". Thesis, Brunel University, 2013. http://bura.brunel.ac.uk/handle/2438/7359.

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This thesis reports research work in the development of biocomposites based on whole utilisation of renewable wheat straw for industrial applications. The concept of “whole utilisation” is based on a previous work on a novel twin-screw extrusion technology for processing of feedstock in wheat straw reinforced bio-composites. It demonstrated that straw raw material could be restructurised into a feedstock with cellulose fibre finely dispersed in the non-cellulose matrix, which can be utilised as a bonding phase without having to be removed as in conventional processes to extract the cellulose. The whole straw can thus be utilised to avoid waste of materials and the negative impacts to environment associated with the extraction process. Raw wheat straw in this research was prepared in three ways: size reduction through mechanical milling, pre-treatment by aqueous NaOH solution and deep preparation with aqueous NaOH solution soaking followed by extrusion fractionation. Prepared wheat straws were processed into varieties of forms according to the applications. They were hot-compressed into self-reinforced composite with good flow ability and also processed through extrusion and compression moulding to compound with other biopolymers as good filler. The relationships of processing parameter and property, as well as formulation and property were established for each form of product, which provides a key understanding of the whole development circle of an end product. Through this research, scientific and technical problems has been addressed in materials formulation/processing, product design/manufacturing, enhancement of functionality/ performance as well as economical/environmental assessment so as to develop a series of cost-effective bio-composites and products, which satisfy diverse technical and environmental performance requirements in the industrial sectors across packaging, horticulture, building/construction and shooting sports.

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Ottoni, Breno Luiz [UNESP]. "A relação da comunicação e as embalagens biodegradáveis: um paradigma para a destinação final". Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/143433.

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É estimado que a geração de resíduos sólidos passará de 1,3 bilhão para 2,2 bilhões de toneladas até 2025, ocasionando problemas ambientais, sociais e, consequentemente, à saúde pública. A maior problemática neste aspecto envolve o destino inadequado dos resíduos, e no Brasil ainda se destina pouco resíduos à triagem para reciclagem ou compostagem. Neste cenário, as embalagens plásticas oriundas de fonte não renovável de energia possuem baixas taxas de reciclagem. Desta forma, surgem os bioplásticos como alternativa, por serem em sua maioria biodegradáveis. Este estudo visa discutir os aspectos comunicacionais relacionados diretamente às embalagens de bioplásticos e apresentar como a função comunicação nas embalagens podem contribuir para fornecer informações relevantes aos consumidores, a fim de minimizar o problema da destinação inadequada. Utilizou-se a pesquisa qualitativa como método a alcançar os objetivos propostos. Conclui-se que a comunicação, seja nas embalagens de plástico ou bioplástico, deve promover as ações nas pessoas: a não geração, a redução, a reutilização e a reciclagem de resíduos sólidos, gerando, desta forma, um ciclo de solução nas problemáticas abordadas neste estudo.
It is estimated that the solid waste generation will grow from 1.3 billion to 2.2 billion tons by 2025, causing environmental and social problems and therefore, to public health.The biggest problem on this aspect involves the inappropriate disposal of waste and Brazil still intended for little waste sorting for recycling or composting. In this scenario, the plastic packaging from non-renewable energy source have low recycling rates. Thus, bioplastics come as an alternative because they are biodegradable in their majority. This study aims to discuss the communication aspects directly related to bioplastics packaging and presenting how communication function in packaging can help to providing relevant information to consumers in order to minimize the problem of improper disposal. The qualitative research was used as a method to achieve the proposed objectives. It can be concluded that communication, whether in plastic or bioplastic shall promote the actions on people about not generation, reduction, reuse and recycling of solid waste, thus creating a solution cycle on the addressed problems in this study.

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Romeira, Karoline Mansano. "Desenvolvimento e caracterização de bioplástico obtido a partir do amido residual proveniente da industrialização de batata frita /". Araraquara, 2019. http://hdl.handle.net/11449/191222.

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Orientador: Rondinelli Donizetti Herculano
Resumo: Durante o processamento industrial das batatas fritas há a produção de uma grande quantidade de amido residual proveniente da lavagem da matéria prima. Os biopolímeros, tipo amido, têm sido propostos para formulação de materiais biodegradáveis. A aplicação do amido na produção de bioplástico se baseia nas propriedades químicas, físicas e funcionais para formar géis e filmes. O objetivo desse estudo foi desenvolver bioplásticos elaborados a partir de amido residual, utilizando diferentes proporções de amido residual e glicerol combinado com alginato e com ácido acético; caracterizar os materiais obtidos quanto à composição e características das ligações formadas, contaminação microbiológica, propriedades mecânicas e características de barreira; e aplicar o bioplástico, utilizando o método de imersão, em frutos de mamão (Carica papaya), avaliando qualitativamente os resultados obtidos. Os resultados apresentados expressam que as soluções filmogênicas produzidas a partir de amido são viáveis para a obtenção de filmes, sendo possível fabricar bioplásticos com as duas composições propostas. As análises de viabilidade microbiológicas e as análises de cromatografia gasosa apontaram que os bioplásticos, em ambas composições, se tornam microbiologicamente estáveis e ausentes de solventes controlados, como o toluol. No FTIR observou-se que ligações de hidrogênio foram formadas em ambas as amostras e essas ligações de hidrogênio conferiram as amostras diferentes características mecânica... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: During industrial processing of potato, a large amount of residual starch is produced from the washing of the raw material. Starch-like biopolymers have been proposed for formulation of biodegradable materials. The application of starch in bioplastic production is based on chemical, physical and functional properties to form gels and films. The aim of this study was to develop bioplastics made from residual starch using different proportions of residual starch and glycerol combined with alginate and acetic acid; characterize the materials obtained for the composition and characteristics of the formed bonds, microbiological stability, mechanical properties and barrier characteristics; and to apply the bioplastic, using the immersion method, in papaya fruits (Carica papaya), qualitatively evaluating the obtained results. The presented results express that the filmogenic solutions produced from starch are viable to obtain films, being possible to manufacture bioplastics with the two proposed compositions. Microbiological viability analyzes and gas chromatography analyzes indicated that bioplastics in both compositions become microbiologically stable and absent from controlled solvents such as toluol. In the FTIR it was observed that hydrogen bonds were formed in both samples and these hydrogen bonds gave the samples different mechanical characteristics. The higher the starch: glycerol ratio, the greater the elongation of the sample in the stress versus strain test, and the more ... (Complete abstract click electronic access below)
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Rijkers, Jessica Carolina Cornelia. "Alinea : The beginning of a new train of thought, Implementing (coloured) bioplastic into handwoven textile design". Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-26578.

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Within Alinea, the purpose is to explore the use of bioplastic as unconventional yarn in the traditional technique of handweaving. The focus toward bioplastic as a design material and the technique of handweaving as the fabrication technique to generate broader alternatives for using bioplastic materials in woven textile design. Described through experimental and practise-based research, handwoven bioplastic samples have been explored to investigate the methods of structures and bindings, gradient colouring and print design within bioplastic and weaving. With the attempt to make bioplastic more accessible for the textile industry. The experimental design research resulted in scaled prototypes that showcase a collection of seven pieces that present various design possibilities and potentials regarding bioplastic within the textile weaving technique, including distinct structural tactile qualities bioplastics can offer to the field of textile. It can be concluded that bioplastic can play a role in becomes a desirable material steering textile design towards a more sustainable future in the textile design field. Furthermore, give handwoven materials new aesthetics by producing unique structures and tactile features.

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Macias, Diego. "Topological (Bio)Timber: An Algorithm and Data Approach to 3d Printing a Bioplastic and Wood Architecture". University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1491305462260965.

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Kumaraswamy, Pillai Subha. "Functionalized polymer building blocks for high performance bioplastic production using novel green catalysts and recycled vegetable oil". Doctoral thesis, Université Laval, 2014. http://hdl.handle.net/20.500.11794/25339.

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Cette thèse de doctorat a pour objectif le développement d'un catalyseur hétérogène très actif et sélectif pour la conversion d'huiles végétales usées en monomères pour le développement de bioplastiques via la réaction d’auto-métathèse. Le méthyltrioxorhénium supporté sur l’alumine mésoporeuse modifiée avec ZnCl2 s’est avéré un catalyseur actif pour l'auto-métathèse de l'oléate de méthyle, une molécule modèle pour les triglycérides des huiles. Les produits obtenus à partir de la métathèse de l'oléate de méthyle comprennent, un diester, le 1,18-octadecenedioate et un alcène, 9-octadécène, qui peut être utilisé comme monomère pour la synthèse des polymères lorsqu'il est associé à d'autres molécules. Les conditions de réaction telles que la température, le temps de réaction et le promoteur utilisé ont été optimisées pour obtenir un rendement élevé en produits de la métathèse de l'oléate de méthyle. Le catalyseur 3% MTO/ZnCl2-Al2O3-meso avec un rapport Al/Zn de 8 à la température de réaction de 45°C pendant 60 min a été trouvé actif pour la métathèse de l'oléate de méthyle. Il a été également observé que les autres halogénures métalliques et des chlorures n'ont pas favorisé la réaction comme le ZnCl2. L'amélioration de l'activité du catalyseur par l’addition de ZnCl2 à Al2O3-méso a été expliquée en raison de la nature acide de Lewis améliorée par le ZnCl2. Les études cinétiques ont montré que le catalyseur a été très actif permettant une conversion supérieure à 80% en 30 min de réaction entre 25°C et 60°C. L'activité catalytique à la température ambiante était aussi encourageante pour l'auto métathèse de l'oléate de méthyle. Les conditions opératoires optimisées pour la métathèse de l'oléate de méthyle ont par la suite été étendues à l'application de triglycérides, en l’occurrence la trioléïne qui est abondante dans l’huile de tournesol et autres huiles végétales. Le catalyseur a été trouvé actif avec la formation de l'alcène 9-octadécène ainsi que des dimères et des trimères de la trioléine. Le catalyseur à base de MTO a été actif pour la formation des produits de métathèse désirés et le produit non désiré de métathèse comme le polymère réticulé formé par la réaction à catalyse homogène a été évité.Les résultats prometteurs pour la métathèse des trioléïnes prouvent que le catalyseur 3% MTO/ZnCl2-Al2O3-meso peut être utilisé pour la métathèse des huiles végétales comme l'huile de tournesol riche en acide oléique qui contient la trioléïne comme sa principale composante.
This doctoral thesis aims at the development of highly active and selective heterogeneous catalyst for conversion of used vegetable oils into monomers for bioplastic development using self-metathesis reaction. The catalyst based on methyltrioxorhenium supported on mesoporous alumina modified with ZnCl2 was found to be an active catalyst for self-metathesis of methyl oleate, a model molecule for triglycerides of oils with high turnover number. The products obtained from the metathesis of methyl oleate include the diester, 1,18-Octadecenedioate and an alkene, 9-Octadecene which can be used as monomer for polymer synthesis when reacted with other molecules. The reaction conditions such as temperature, reaction time, the promoter used were optimized to obtain high yield of products from the metathesis of methyl oleate. The catalyst 3% MTO/ZnCl2-Al2O3-meso with Al/Zn ratio of 8 at reaction temperature of 45°C for 60 min was found to be active for metathesis of methyl oleate. It was also found that the other halides and metal chlorides did not promote the reaction similar to ZnCl2. The enhancement of activity by addition of ZnCl2 to Al2O3-meso was found to be due to the Lewis acidic nature enhanced by addition of ZnCl2. The kinetic studies showed that the catalyst was highly active resulting in conversion> 80% within 30 min of reaction between 25°C to 60°C. The catalytic activity at room temperature was also promising proving it to be a very efficient catalyst for self metathesis of methyl oleate. The conditions optimized for methyl oleate metathesis was extended for the application of triolein, the abundant triglyceride present in the high oleic sunflower oil and other vegetable oils. The catalyst was found to be active with formation of the alkene 9-Octadecene and the dimers and trimers of triolein as desired metathesis products. The MTO based catalyst was active in forming the desired metathesis product and the undesired product namely the cross-linked polymer formed with the homogeneously catalyzed reaction was avoided. The promising results for the metathesis of triolein prove that the catalyst 3% MTO/ZnCl2-Al2O3-meso can be used for the metathesis of vegetable oils such as high-oleic sunflower oil which contains triolein as its major component.

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19

Jin, Yutong. "Environmental Input-output Analysis and Its Application to Multi-region Studies". Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/29591.

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Our world is beleaguered by environmental and socioeconomic problems, such as natural resources degradation, natural hazards, climate change, unemployment, and inequality. Trade supply chains are recognised as important means to address environmental and socio-economic challenges. The world has benefited from trade in many ways, such as promoting economic growth, opening the global market for all countries, and creating jobs. However, trade is likely to increase environmental externalities at both national and global level. Trade can directly affect local environment through overexploitation of natural resources and substantial pollution. One reason for this is that trade is mainly driven by regions’ differing natural resource endowments. Considering the adverse environmental impact of trade and supply chains, as well as their effects on societal and economic development, domestic and international trade supply chains play a key role in addressing regional and global environmental challenges, and thus contribute to achieving Sustainable Development Goals (SDGs) – a global plan adopted by all United Nations (UN) members for a better and more sustainable future. This thesis applies a quantitative interdisciplinary approach - multiregional input-output (MRIO) analysis to estimate the environmental and socioeconomic impacts of supply chains in three case studies: (i) calculate material footprint in four megacities of China by linking Chinese MRIO to the Global MRIO database Eora, (ii) estimate direct and indirect economic loss and spillovers of desertification in China, as well as the nutrient loss caused by desertification, by applying an improved input-output (IO)-based disaster model, (iii) investigate how Greenhouse Gas (GHG) emissions, land use, and employment will be affected by switching from petroleum-based plastics to bio-based plastics, with an improved IO technique for estimating the substitution effects of bioplastics.

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20

Frenna, Giammarco <1992&gt. "LCA of the conversion of urban bio-wastes into bio-based polymers in a bio-refinery (PHA-based bioplastic)". Master's Degree Thesis, Università Ca' Foscari Venezia, 2019. http://hdl.handle.net/10579/14428.

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INTRODUZIONE La sfida del progetto RES URBIS consiste nel ridurre i residui da smaltire dopo i trattamenti finali dei rifiuti con la possibilità di creare all’interno della bio-raffineria un polimero a base biologica che può essere introdotto nel settore della bioindustria al fine di chiudere il cerchio del riciclo in un’ottica di economia circolare. OBIETTIVI, AREA DI RICERCA, RISULTATI Questo studio è finalizzato a valutare gli impatti ambientali della conversione di diversi tipi di rifiuti urbani in bio-prodotti (come bioplastiche, solventi a base biologica, fibre per Biocompositi) basati sui PoliIdrossiAlcanoati (PHA). L’identificazione dei potenziali impatti ambientali viene sviluppata attraverso l’analisi del ciclo di vita del processo di produzione di PHA nell'ambito del trattamento dei rifiuti organici (cioè fanghi di depurazione, frazione organica dei rifiuti solidi urbani (FORSU) e rifiuti del giardino) all’interno degli impianti di trattamento delle acque reflue e dei rifiuti utilizzando un modello LCA (Lyfe Cycle Assessment) con il quale vengono sviluppati diversi scenari di confronto (Digestione Anaerobica, Incenerimento, Discarica, bio-raffineria RES URBIS) Lo studio è stato condotto sull'impianto di trattamento delle acque reflue di Treviso, in Italia, dove è presente l’impianto pilota e su diversi tipi di impianti di trattamento dei rifiuti a Copenaghen, in Danimarca e in vari cluster europei facenti parte del progetto. In tutti i casi l'obiettivo generale è dimostrare che il processo è rilevante. Il progetto si sviluppa all’interno del Consorzio RES URBIS, in particolare nel dipartimento di Ingegneria Ambientale presso l'Università Tecnica della Danimarca e nel dipartimento di Scienze Ambientali, Informatica e Statistica presso l'Università Ca 'Foscari di Venezia. Nello specifico il primo si occupa della parte di LCA e il secondo della parte di implementazione del processo. I risultati sono destinati ad essere utilizzati dagli stakeholder (RES URBIS, Comuni responsabili della gestione dei rifiuti e delle loro società di gestione dei rifiuti pubblici) per capire se lo scenario RES URBIS di produzione di PHA attraverso il trattamento delle acque reflue presenta vantaggi ambientali rispetto alla gestione dei rifiuti con altre tecnologie (ad esempio AD, discarica, compost). METODO Il progetto si basa sullo studio della produzione di PHA in un impianto pilota presente all’interno dell’impianto di depurazione delle acque della città di Treviso (TV) in Italia e sulle possibili integrazioni in piena scala in città come Copenhagen o la provincia di Trento. La prima limitazione del progetto è riferita ai due diversi tipi di dati che usiamo per eseguire lo scenario; per questo motivo, lo studio della rappresentatività dei dati, dell'incertezza, della sensibilità e della qualità dei dati è una parte fondamentale di questo LCA. Il software utilizzato è EASETECH, un modello LCA specializzato sviluppato da DTU (Technical University of Denmark) (Clavreul et al., 2014) e lo studio è stato condotto secondo i requisiti della ISO 14044: 2006 e del Manuale ILCD. Secondo questo manuale, si fa riferimento al supporto decisionale basato sul ciclo di vita di un sistema tecnologico installato in un pre-esistente impianto o nella conversione di una tecnologia esistente in una nuova con migliori caratteristiche. Per questo motivo, questa LCA è classificata consequenziale.

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21

SPINELLI, ROSANGELA. "Life Cycle Assessment del processo di valorizzazione di rifiuti organici mediante l’utilizzo di insetti per l’ottenimento di bioplastiche". Doctoral thesis, Università degli studi di Modena e Reggio Emilia, 2020. http://hdl.handle.net/11380/1200386.

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L'aumento della produzione di rifiuti è una delle maggiori preoccupazioni in molte aree del mondo. Una rigida normativa sulla tracciabilità dei rifiuti, che ne impedisce usi alternativi e comporta costi non indifferenti, ed una crescente domanda di fonti rinnovabili per la produzione di energia, prodotti chimici, combustibili e materiali, sta portando ad una forte richiesta di tecnologie innovative per la gestione e la valorizzazione dei rifiuti, in particolare per deiezioni/scarti zootecnici e frazione organica dei rifiuti urbani. Negli ultimi anni sono state proposte strategie alternative per la valorizzazione di tali materiali di scarto che comprendono approcci termochimici (ad esempio pirolisi e trattamento idrotermico), l'uso di fonti energetiche meno convenzionali come microonde, ultrasuoni o energia meccanica, fermentazione e digestione microbica insieme ad ulteriori bio-based strategy, tra cui la bioconversione per mezzo di insetti rappresenta sicuramente una delle tecniche più promettenti. In effetti la conversione delle biomasse di rifiuti organici in preziose biomolecole è una caratteristica peculiare di diversi tipi di insetti. Tra questi insetti l’Hermetia illucens (Linneus 1758, meglio noto come Black Soldier Fly - BSF) rappresenta un esempio eccellente, con numerosi vantaggi rispetto ad altre specie. BSF è una mosca non nociva (gli adulti vivono solo per pochi giorni, non si nutrono e non trasmettono agenti patogeni), le cui larve sono in grado di lavorare e svilupparsi molto rapidamente su substrati diversi tra cui sottoprodotti agricoli, escrementi di bestiame e rifiuti organici, limitando in modo significativo la crescita batterica e lo sviluppo di cattivi odori. Nonostante i problemi o le considerazioni ambientali e sulla salute umana, le prepupe di BSF sono buone fonti di lipidi, proteine e chitina, che sono state sfruttate negli ultimi anni nella produzione di biodiesel, mangimi e bioplastiche. In questo studio la pollina viene sfruttata per allevare prepupe di BSF che verranno frazionate in laboratorio per purificare la frazione proteica, lipidica e quella chitinosa. A partire dalle proteine si è individuata una appropriata miscela di componenti/additivi per l’ottenimento di bioplastiche funzionali ad un loro uso in agricoltura. In particolare lo scopo di questo lavoro è la valutazione ambientale mediante analisi LCA di tutti i diversi processi, dall'allevamento di BSF alla produzione di bioplastiche, passando attraverso la fase di isolamento, caratterizzazione ed estrazione della frazione lipidica, proteica e chitinosa. Sebbene il numero di studi che hanno valutato la bioconversione dei rifiuti organici tramite insetti (in particolare BSF) sia cresciuto considerevolmente negli ultimi anni, solo alcuni di essi riportano l’applicazione della metodologia LCA, seppur limitatamente al solo processo di bioconversione, valutando solo l'impatto ambientale associato alla produzione di prepupe di BSF e confrontandolo con fonti di alimentazione più convenzionali. Il presente studio, applicando l'analisi LCA a un sistema complesso, che parte dall’allevamento fino ad arrivare alla produzione di bioplastiche, ha l'obiettivo di analizzare in modo sperimentale alcuni aspetti metodologici che non sono ancora stati approfonditi fino ad oggi. Il progetto rappresenta perciò una sfida da affrontare con l'approccio del Life Cycle Thinking, ma è anche una opportunità per studiare gli aspetti deboli degli attuali modelli di valutazione ambientale basati sull’analisi LCA, come ad esempio le emissioni locali e indoor, per le quali è stato proposto un framework di calcolo (per il comparto aria) sviluppato a partire dai metodi EcoIndicator99, USEtox e dal modello Gaussian Plume Modeling.
The increasing in waste production is among the major concern in many areas around the world. A strict regulations in relation to its traceability, which prevents any alternative uses and carries considerable costs, and the increasing demand for renewable sources for production of energy, chemicals, fuels and materials, is leading to a strong demand for innovative technologies for the management and valorisation of waste, particularly for livestock manure and organic fractions of municipal waste. In the last years, alternative strategies for enhancing such waste materials have been proposed that include thermochemical approaches (for example pyrolysis and hydrothermal treatment), the use of less conventional energy sources such as microwaves, ultrasounds or energy mechanical, fermentation and microbial digestion together with additional bio-based strategies, among which bioconversion by insects is certainly one of the most promising techniques. Indeed conversion of organic waste biomasses into valuable biomolecules is a peculiar characteristic of several kinds of insects. Among these insects Hermetia illucens (Linneus 1758, better known as Black Soldier Fly - BSF) represents an excellent example, possessing several advantages with respect to other species. Black Soldier Fly is a non-pest fly (adults live for a few days only, they do not feed and do not transmit pathogens), whose larvae are able to process and to develop very quickly on different substrates, including agricultural by-products, livestock excrements and organic waste, significantly restraining bacterial growth and bad odours development. Despite environmental and human health issues or considerations, BSFs prepupae are good sources of lipids, proteins and chitin, which have been exploited in recent years in the production of biodiesel, feed and bioplastics. In this study poultry manure is exploited to breed BSFs prepupae which will be fractioned in a laboratory in order to purify the protein, lipid and chitin fraction. Starting from BSF proteins an appropriate mixture of components and additives was identified to obtain bioplastics functional to their use in agriculture. Particularly the aim of this work is the environmental assessment through LCA analysis of all of the different processes from BSFs breeding to the bioplastics production, by passing through the phase of isolation, characterization and extraction of protein, lipid and chitinous fraction. Although, the number of studies evaluating bioconversion of organic waste by insects (in particular by BSFs) has considerably grown during the recent years, only a few of them reported the application of LCA methodology, limitedly to the only bioconversion process, thus assessing the environmental impact associated with the production of BSF prepupae, and comparing it with more conventional feed sources. The present study, applying the LCA to a complex system, which starts from breeding up to the production of bioplastics, aims to experimentally analyze some methodological aspects that have not yet been studied in depth to date. The project is a challenge to be tackled with a Life Cycle Thinking approach, but it is also an opportunity to study the weak aspects of the current LCA-based environmental assessment models, for example the local and indoor emissions, for which, a calculation framework (for air compartment) was developed based on the EcoIndicator99 and USEtox methods and the model Gaussian Plume Modeling.

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22

Choi, Suh-Yeon. "Metabolomic and transcriptomic analysis of polyhydroxybutyrate (PHB) accumulating Arabidopsis and switchgrass unveiling metabolic consequences of bioplastic accumulation in plant plastids /". [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3369821.

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Thesis (Ph.D.)--Iowa State University, 2009.
Title from PDF title page (ProQuest website, viewed on October 14, 2009) Supplemental files include tables and scatter plot slides. Includes bibliography.

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23

Gilfillan, William N. "Developing starch-based polymer composites". Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/86612/6/William_Gilfillan_Thesis.pdf.

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This project aim was to replace petroleum-based plastic packaging materials that pollute the environment, with biodegradable starch-based polymer composites. It was demonstrated that untreated sugar cane bagasse microfibres and unbleached nanofibres significantly improved the physical, mechanical and chemical properties of starch films, while thermal extrusion of starch with alcohol improved the stiffness and the addition of aconitic acid cross-linked the film making it moisture resistant and extensible.

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24

Balaguer, Grimaldo María de la Paz. "Development of active bioplastics based on wheat proteins and natural antimicrobials for food packaging applications". Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/48520.

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This PhD dissertation focuses on the development of renewable and biodegradable active films based on chemically-modified wheat gliadin proteins endowed with antimicrobial capacity owing to the incorporation of naturally-occurring bioactive compounds, namely cinnamaldehyde, natamycin, and lysozyme. Gliadin proteins were treated with cinnamaldehyde at acidic pH and films were produced by casting. The resulting protein-based films presented improved functional properties (mechanical, barrier, and water resistance), and biochemical evidence of the formation of a more compact network whose degree of cross-linking increased with the amount of cinnamaldehyde incorporated into the gliadin-ethanolic solution. Free cinnamaldehyde not participating in the cross-linked reaction remained entrapped in the protein matrix at low relative humidity conditions. The sensitivity of the films to moisture owing to the hydrophilic character of gliadins provided a trigger and control mechanism for the release of cinnamaldehyde in moderate and high relative humidity environments, similar to conditions occurring in packaged food products. The antimicrobial properties of the films developed were tested in vitro by vapor diffusion assays against common food spoilage fungi (Penicillium expansum and Aspergillus niger), showing great effectiveness. Application of these active films to the preservation of two foodstuffs, sliced bread and cheese spread, gave promising results, lengthening fungal growth lag phase and minimizing fungal growth extension.
Balaguer Grimaldo, MDLP. (2015). Development of active bioplastics based on wheat proteins and natural antimicrobials for food packaging applications [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48520
TESIS
Premiado

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25

Macagnan, Karine Laste. "Otimização de metodologia de extração química clássica de poli(3-hidroxibutirato) sintetizado por Ralstonia solanacearum". Universidade Federal de Pelotas, 2014. http://repositorio.ufpel.edu.br:8080/handle/prefix/3698.

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Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul - FAPERGS
O poli(3-hidroxibutirato) [P(3HB)] é o biopolímero mais estudado e caracterizado dentre a família dos polihidroxialcanoatos (PHAs), termoplásticos que têm como principais características a rápida biodegradabilidade e a biocompatibilidade. O processo de recuperação do bioplástico consiste em uma etapa importante no processo de produção. O desenvolvimento de metodologias mais seguras, econômicas e ambientalmente corretas, e que permitam um alto rendimento desse biopolímero, torna-se necessário para uma produção de P(3HB) economicamente e ecologicamente atrativa. Portanto, o objetivo do trabalho foi otimizar a metodologia clássica de recuperação de poli(3-hidroxibutirato) utilizando clorofórmio como solvente. O bioprocesso foi realizado em duas etapas, utilizando linhagem de Ralstonia solanacearum. O inoculo foi produzido em Erlenmeyers aletados de 500 mL, contendo 160 mL de meio YM e 40 mL de suspensão bacteriana, mantidos em incubador agitador orbital por 24 h, 150 rpm e 28 °C. A segunda etapa, produção de P(3HB), foi realizada utilizando Erlenmeyers aletados de 500 mL, contendo 160 mL de meio F4 e 20 % de inóculo, mantidos em 28 °C, 200 rpm e 72 h em incubador agitador orbital. Após a fermentação, as células foram separadas por centrifugação a 10.000 x g, lavadas com solução salina 0,89 % e secas a 56 °C. O acúmulo de P(3HB) na célula foi quantificado por cromatografia gasosa. A metodologia de extração foi otimizada em relação aos parâmetros: tempo de extração (2 h a 15 min), separação da biomassa/solução extrativa (papel filtro ou funil de separação), estado de célula (seca ou fresca) e proporção de solvente (10:1, 20:1 e 40:1 v/m). Por evaporação da solução extrativa foram obtidos filmes poliméricos. Os filmes recuperados foram analisados física e quimicamente por Espectroscopia de Infravermelho por Transformada de Fourier (FTIR), Calorimetria Diferencial de Varredura (DSC), Análise Termogravimétrica (TGA) e Cromatografia de Permeação em Gel (GPC). O acúmulo de P(3HB) foi de 51,15 %. Os maiores rendimentos de filme foram obtidos após 30 min de aquecimento, utilizando funil de decantação para separar a solução extrativa da biomassa, célula seca, e proporção de solvente 40:1 v/m, alcançando-se recuperação de 98 % do polímero acumulado. A análise dos filmes através de FTIR resultou em bandas características de P(3HB). Os filmes oriundos de células secas tiveram temperaturas inicial e final de degradação e grau de cristalinidade superiores aos filmes de célula fresca. Todavia, os últimos apresentaram massa molar maior do que os primeiros. A metodologia clássica de extração química de poli(3-hidroxibutirato) por clorofórmio com aquecimento pode ser otimizada, resultando em redução de 75 % do tempo de aquecimento e separação da biomassa/solução extrativa mais rápida e econômica. Porém, não foi possível substituir a utilização de massa celular seca por fresca nem reduzir a proporção inicial de solvente de 40:1 (v/m).
Poly (3-hydroxybutyrate) [P(3HB)] is the most important biopolymer from the polyhydroalcanoates (PHAs) families, and they are thermoplastics with rapid biodegradability and biocompatibility. The recovery process of bioplastics is an important stage in the production process. Development of safe, economic and environmentally friendly methodologies, that result in high yield biopolymer, is necessary for the attractive P(3HB) production. Therefore, the objective was to optimize the classical methodology for poly (3-hydroxybutyrate) recovery using chloroform as solvent. The bioprocess was performed in two phases, with Ralstonia solanacearum strain. In the first phase, inoculum production, was performed in Erlenmeyer 500 mL flasks, containing 160 mL medium YM and 40 mL bacterial suspension. The flasks were incubated in shaker for 24 h, 150 rpm and 28 °C. The second phase, P(3HB) production, was performed using Erlenmeyer 500 mL flask, containing 160 mL medium F4 and 20 % (v/v) inoculum, maintained in 28 °C, 200 rpm and 72 h. After fermentation cells were separated by centrifugation at 10,000 x g, washed with saline (0,89 % w/v) and dried at 56 °C. P(3HB), accumulation was quantified by gas chromatography. The extraction methodology was optimized according to: extraction time (2 h - 15 min), extractive solution/biomass separation (paper filter or separation funnel), state of cell (dry or fresh), and solvent ratio (10:1, 20:1 and 40:1 v/m). Polymeric films were obtained by evaporation from extractive solutions and they were analysed by Fourier Transform Infrared (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA) and Gel Permeation Chromatography (GPC). The P(3HB) accumulation was 51,15 %. Highest yields of film were obtained after 30 min heating, by funnel for extractive solution recovery, dry cell and solvent ratio 40:1 v/m; and highest recovery was 98 % of cumulated polymer in the cell. Characteristic bands of P(3HB) were obtained to produced films by FTIR analysis. Films from dried cells showed initial and final degradation temperature and crystallinity degree higher than and films these from fresh cell, however, they showed higher molar weight than the first ones. The classical chemical extraction of P(3HB) by chloroform with heating can be optimized, resulting in a 75 % reduction as well heating time extraction solution most fastest and economical. However, wasn’t possible replace the dry cell mass use by fresh cell mass or reduce the initial solvent proportion [40:1 (v/m)].

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Paulenka, Igor. "Funkcionalizace polyolefinů roubováním". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-316409.

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The theoretical part of the diploma thesis is focused on the funcionalization of polyolefins in order to accelerate their degradation and to increase their carbon content from renewable resources with focus on hydroxyacids. The experimental part is focused on preparing samples and studying the properties of the polypropylene and polyethylene blends with the polylactide with different contents of the initiator and the maleic anhydride. Samples were evaluated by determining the degree of conversion maleic anhydride, differential scanning calorimetry, infrared spectroscopy, melt flow index and mechanical properties.

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Stahl, Florian Felix [Verfasser], Klaus [Akademischer Betreuer] Menrad, Klaus [Gutachter] Menrad y Sebastian [Gutachter] Goerg. "Influences on purchase intention for bioplastic products and consumer preferences for bio-based apparel in Germany / Florian Felix Stahl ; Gutachter: Klaus Menrad, Sebastian Goerg ; Betreuer: Klaus Menrad". München : Universitätsbibliothek der TU München, 2021. http://nbn-resolving.de/urn:nbn:de:bvb:91-diss-20210601-1575047-1-9.

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Giliberti, Gianluca. "Development of a pilot scale process for polyhydroxyalkanoates production from food waste". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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The focus of this thesis was on investigation of culture selection step for PHA production by using food waste as no-cost feedstock with mixed microbial cultures (MMC). PHAs (polyhydroxyalkanoates) are biologically synthesized polymers that can be produced from renewable resources and are completely biodegradable. Because at the present times the demand of alternatives to replace conventional plastics is rapidly growing due to environmental issues, the possibility to produce PHAs on a large scale by using waste materials as carbon source is considered to be very attractive both from an environmental and economic point of view. The experimental work was developed during a traineeship carried out at the Laboratory of Biochemical and Chemical Engineering of NOVA School of Science and Technology. The selection step was conducted through the employment of a sequential batch reactor (SBR) at pilot scale and had the main goal of getting a high performance process while ensuring a satisfying reactor stability. Operations were performed using fermented food waste provided by ValorSul. ValorSul is a Portuguese company which is responsible for the management of urban solid waste produced in five municipalities in the area of Lisbon. In particular, the aim was to assess selection step outcomes while operating with a high OLR (organic loading rate). Few studies on MMC culture selection step conducted applying high OLR values are currently reported in literature. Two different SBR operating conditions were investigated and compared in this thesis work: HRT (hydraulic retention time) equal to 1 day in a first phase and HRT equal to 0.66 day in a second phase. After several cycles, a PHA-rich culture was selected from the SBR and it was inoculated in fed-batch lab scale reactors during accumulation tests with the main aim of evaluating the maximum reachable PHA content and PHA productivity for both two operating conditions configurations.

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Eriksson, Joakim. "Miljöpåverkan av bioplast från skogsindustriellt avloppsvatten : En jämförande livscykelanalys av polypropen (PP) och polyhydroxyalkanoater (PHA) från Gruvöns massa- och pappersbruk". Thesis, Karlstads universitet, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-79924.

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I den här studien har en beräkningsmodell byggts för hur PHA skulle kunna produceras av substrat i avloppsvatten från Gruvöns bruk. Därefter har en jämförande livscykelanalys utförts där PP-sugrör inom Europa ersätts med PHA-sugrör från bruket. Målet med studien är att utvärdera och jämföra miljöpåverkan för en engångsprodukt av PHA med en engångsprodukt av PP. Syftet är att undersöka ett alternativt material till PP på grund av att fossila resurser är ändliga samt att alternativa material kommer krävas i och med europeiska kommissionens förbud mot engångsplast som träder i kraft 2022. Arbetet utförs också för att bidra med mer forskningsunderlag gällande PHA från restströmmar. Livscykelanalysen utfördes med ISO-standard: 14040 och 14044 som riktlinje för utförande. 1 ton sugrör valdes som funktionell enhet och hela produktens livscykel undersöktes med undantag för användningsfasen. PHA-produktion på bruket beräknades teoretiskt där mass- och energiflöden från modellen sedan användes för miljöbedömning. SimaPro valdes som programvara för LCA-beräkning, miljödata hämtades från databasen Ecoinvent 3 och ELCD där 10 av 18 miljöfaktorer inom metoden ReCiPe midpoint (h) undersöktes kompletterat med kumulativt energibehov (CED). Resultaten i studien visar en minskning av miljöpåverkan med 99 % om sugrör av PP skulle ersättas med sugrör av PHA från Gruvöns bruk. Samtidigt beräknades CED öka med cirka 50 %. Analyser av resultatet visar att giftighet för ekosystem i sjöar och hav vid materialframställning för PP är de största faktorerna för PP-sugrörets påverkan, motsvarande cirka 85 % av den totala miljöpåverkan. Inkludering av fler produktionsvariationer indikerar också att det finns potential att ytterligare sänka miljöpåverkan från PHA-sugrör samt att få en lägre energianvändning än för PP-sugrör genom att ändra metod för extraktion samt temperatur i fermenteringsprocessen. Resultaten är osäkra på grund av LCA-verktygets osäkerheter, brist på miljödata samt brist på studier. Resultaten kan dock användas för att se trender och potential. Ett exempel är att ingen större skillnad ses mellan engångsprodukter av PP och PHA när enbart klimatpåverkan och energi för produktion undersöks men när hela livscykeln undersöks med fler miljöfaktorer så verkar PP ha klart högre miljöpåverkan än PHA. Slutsatsen som dras är att engångsprodukter av PHA från varma restströmmar har potential att ersätta engångsprodukter av PP på ett för miljön hållbart sätt. Det kan vara en möjlig lösning till att fortsätta producera engångsprodukter som berörs av plastförbudet samt att lätta på en del av problematiken kring utarmning av fossila resurser. Mer studier gällande möjliga användningsområden samt en småskalig pilotanläggning på Gruvöns bruk rekommenderas som vidare steg för att utforska potentialen av PHA från restströmmar.
In this study, a calculation model has been built on how PHA could be produced from forest industrial wastewater at Gruvöns pulp- and paper mill. Subsequently, a comparative life-cycle analysis has been carried out where production of PP-drinking straws in Europe is replaced with PHA-straws from the mill. The objective of the study is to assess and compare the environmental impact of a disposable PHA product with a disposable PP product. The purpose of the study is to examine an alternative material for PP due to the finite nature of fossil resources and the fact that alternative materials will be required when the plastic ban from the European Commission on disposable products comes into force 2022. An additional purpose is to provide more research data on PHA from residual streams. The lifecycle analysis was performed with ISO standard: 14040 and 14044 as a guideline and 1 ton of straw was selected as the functional unit. The entire life cycle was examined with an exception of the usage phase. PHA production at the mill was theoretically calculated and mass and energy flows from the model was then used in the environmental assessment. SimaPro was selected as the software for LCA calculation, environmental data was retrieved from the Ecoinvent 3 database and ELCD database. 10 out of 18 environmental factors within the ReCiPe midpoint (h) method were investigated complemented with cumulative energy demand (CED). The results of the study show a 99 % reduction in environmental impact if drinking straws of PP would be replaced with straws from PHA from Gruvön's mill. At the same time, CED was estimated to increase by about 50 %. Analyses of the results show that the toxicity of material production to marine and freshwater ecosystems is the most influential factor in the impact of PP straws, representing around 85 % of the total environmental impact. Expansion of the calculation model showed that there is potential to further reduce the environmental impact of PHA straws as well as the energy requirements to a level that is lower than that of PP straws by changing method of extraction and fermentation. The results are uncertain due to the uncertainties of the LCA tool, lack of environmental data and lack of studies. However, the results can be used to see trends and potential. One example is that no major difference is seen between disposable PP and PHA products when only climate impact and energy for production are examined, but when the entire life cycle is examined with more environmental factors, PP appears to have a significantly higher environmental impact than PHA. The conclusion drawn in the study is that disposable PHA products from hot residual streams have potential to replace disposable PP products in an environmentally sustainable manner. This may be a possible solution to continue producing disposable products that are affected by the plastic ban and to alleviate some of the problems surrounding depletion of fossil resources. Further studies on possible uses and a small-scale pilot plant at Gruvön's mill are recommended as further steps to explore the potential of PHA from residual streams.

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Fakhouri, Farayde Matta. "Bioplasticos flexiveis e biodegradaveis a base de amido e gelatina". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256348.

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Orientadores: Fernanda Paula Collares Queiroz, Lucia Helena Innocentini Mei
Tese (doutorado) - Universidade Estadual dse Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-12T14:25:27Z (GMT). No. of bitstreams: 1 Fakhouri_FaraydeMatta_D.pdf: 8442121 bytes, checksum: 0c402098c4f41a7575fbfc8ec41dc913 (MD5) Previous issue date: 2009
Resumo: O objetivo deste trabalho foi desenvolver um bioplástico flexível, biodegradável e comestível, à base de polímeros naturais de fontes renováveis (amido e gelatina) por processo de extrusão termoplástica seguido de sopro. Inicialmente, foi realizada a caracterização física e funcional de biofilmes à base de amido e gelatina elaborados pela técnica de solução (casting), visando a escolha das melhores formulações para serem utilizadas na produção destes bioplásticos por processo de extrusão e sopro. As soluções filmogênicas de amido de mandioca (nativo e modificado) e milho (nativo, ceroso, ceroso modificado e lipofílico) foram preparadas nas concentrações de 3 e 5% e a de gelatina, na concentração de 10%. Os biofilmes compostos de gelatina e amido (de mandioca ou de milho) foram elaborados nas proporções 4:1, 1:1 e 1:4, plastificadas com sorbitol ou glicerol, sendo 5% para as soluções de gelatina e 10% para as soluções de amido. Todos os biofilmes formados foram visualmente transparentes. A adição de gelatina provocou um aumento na espessura, na permeabilidade ao vapor de água (PVA) e na resistência à tração (RT), provocando também uma diminuição na opacidade dos mesmos. Posteriormente, diferentes ácidos graxos (palmítico, mirístico, cáprico, capróico e caprílico), nas concentrações de 5, 15, 25 e 50%, foram adicionados à mistura de amido lipofílico e gelatina. Esta adição causou, em geral, um aumento da opacidade, da espessura e da elongação, no entanto, ocorreu uma diminuição na RT e da PVA dos biofilmes formados. A melhor formulação de amido lipofílico, gelatina e plastificante (glicerol, sorbitol e ácido mirístico) foi utilizada para a produção de filmes por diferentes técnicas (prensados, prensados e soprados e extrudados). Bioplásticos prensados apresentaram menores valores de RT e maiores valores de solubilidade em água. Os filmes extrudados, obtidos nas mesmas concentrações de amido, gelatina e plastificante, apresentaram-se semi-rígidos, característica não desejável para o objetivo em questão. Com base nestes resultados, foram alteradas as concentrações dos componentes da mistura para permitir a obtenção de bioplásticos com propriedades adequadas pelo processo de extrusão termoplástica. Estes bioplásticos foram caracterizados quanto às propriedades físicas, fisico-químicas, morfológicas, mecânicas, de barreira e térmicas. Os bioplásticos elaborados foram flexíveis, apresentaram expansão durante o sopro e foram visualmente homogêneos, porém, os elaborados com sorbitol apresentaram-se quebradiços após o condicionamento. A adição de gelatina causou uma diminuição no valor de PVA, mas não influenciou a solubilidade em água nem a opacidade dos bioplásticos. A adição de lipídios ocasionou uma diminuição na RT dos bioplásticos, tanto no sentido transversal como no longitudinal em relação ao sentido de produção. Filmes compostos com 10 e 20% de gelatina, sem adição de ácido graxo apresentaram os menores valores de PVA e maiores valores de RT
Abstract: The goal of this research was to develop a flexible, biodegradable and edible film using natural polymers (starch and gelatin) from renewable sources through a process of thermoplastic extrusion followed by blowing. The first step of the research consisted on a physical and functional characterization of starch and gelatin based biofilms produced using the casting technique. The purpose was to select the solutions to be used on the production of these biofilms by extrusion and blowing. The filmogenic solutions of manioc starch (native and modified) and corn (native, waxy, waxy modified and lipofilic) were prepared at concentrations of 3 and 5%. The filmogenic solution of gelatin was prepared at a concentration of 10%. The gelatin and (manioc and corn) starch based biofilms were prepared at ratios of 4:1; 1:1 and 1:4. They were plasticized with sorbitol or glycerol at 5% for the the gelatin solutions and 10% for the starch solutions. All the biofilms obtained were visually transparent. The addition of gelatin resulted in an increase of the film thickness, an increase of the water vapour permeability (WVP), an increase of the tensile strength (TS) and a decrease in the opacity. Different fatty acids (palmitic, miristic, capric, caproic and caprilic) were added to the lipofilic starch and gelatin solution at concentrations of 5, 15, 25 and 50%. These additions resulted in an increase on opacity, thickness and elongation. However, there was a decrease on WVP and TS. The best solution of lipofilic starch, gelatin and plasticizer (glycerol, sorbitol and miristic acid) was used in the production of films by different techniques (pressed, pressed and blowed and extruded). Pressed biofilms showed lower values of strain at break and higher values of water solubility. The extruded films, obtained at the same concentrations of starch, gelatin and plasticizer were found to be semi-rigid, a characteristic not aligned with the objective of theresearch. Based on the results of this first assessment, the concentrations of the components were adjusted with the purpose of obtaining extruded films with the desired properties. The resulting biofilms were characterized for their physical, physico-chemical, morphology, mechanical, barrier and thermical properties. Biofilms in general were flexible, showed expansion during blowing and were visually homogeneous. However, biofilms prepared with sorbitol were cracking very easily after storage. The addition of gelatin resulted in a reduction of the WVP but did not have any influence on the water solubility nor on the opacity of the biofilms. The addition of lipids resulted in a reduction of the TS of the biofilms both in longitudinal and transversal directions. Biofilms with 10 and 20% of gelatin and no fatty acid added showed lower values of WVP and higher values of TS
Doutorado
Doutor em Tecnologia de Alimentos

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Paluchová, Natálie. "Vliv biodegradace bioplastů na kvalitu půdy". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-449334.

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V poslední době se pozornost polečnosti obrátila k mikroplastům. Jsou produkovány různými odvětvími a šíří se napříč prostředím. Po dlouhou dobu byly považovány za inertní, bez dalšího vlivu na rostliny a jiné živé organismy, avšak jak zjistily nedávné studie, mohly by představovat vážnou hrozbu. Několik vědců, včetně nás, se proto začalo soustředit na jejich transport a transformace v životním prostředí. Většina se však zaměřuje pouze na jejich přítomnost v mořských a sladkých vodách, a proto jejich chování ve vzduchu a půdě zůstává nejasné. Kromě toho byla pozornost soustředěna i na bioplasty. Jsou prezentována jako ekologická alternativa, která má vyřešit všechny dosud zmíněné problémy (a další). Avšak často se zapomíná, že jejich hlavní výhoda může být zároveň nevýhodou. Z tohoto důvodu se tato diplomová práce zaměřuje na negativní účinky spojené s přítomností mikroplastů (konkrétně bioplastu poly-(R)-3-hydroxybutyrátu) v půdě jako jejich běžný receptor. Kombinovali jsme respirometrii, elementární analýzu, termogravimetrii a enzymatické testy, abychom zkoumali fyzikálně-chemické změny v půdě vyvolané přítomností bioplastu. Naše výsledky ukázaly negativní vliv na půdní organickou hmotu a zadržování vody v půdě. V tomto smyslu byl zkoumán i tzv. "priming effect", jelikož docházelo k urychlení a také zpomalení rozkladu půdní organické hmoty. Zaznamenali jsme rozdílný vliv vybraných koncentrací biopolymeru na půdu a také vliv půdních vlastností na průběh degradace. V neposlední řadě zvýšení enzymatické aktivity jasně naznačovalo vliv přítomnosti biopolymeru na mikrobiální komunitu. Na základě takových zjištění jsme došli k závěru, že přidání biopolymeru vede k dlouhodobému dopadu na řadu funkcí půdního ekosystému.

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Kurniadi, Muhammad Ardi y Hamid Mohamed. "Green and Global: Internationalization of eco-innovated Born Global firms : Case Study of biocomposite plastic industry". Thesis, Uppsala universitet, Industriell teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-446822.

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Sustainability and eco-innovation trends in business are increasingly diffused globally. The quest for sustainable materials to overcome the alarming global tendency of plastic ubiquity is one of the main reasons for such trends. It draws the attention of international actors in the business ranging from a big incumbent multinational company to a small but international firm. The phenomenon of a small firm that quickly becomes global is pervasive and contributes crucially to the global economy. Due to the born global (BG) novelty, internationalization in BG firms has been elaborated primarily in a general context, excluding the firms and industry-particular characteristics. The study aims to understand the internationalization process of a BG firm equipped with an eco-innovation context at the early stage in the biocomposite industry, using an effectual approach as conceptual lenses. The conceptual lens creates interplay among the combined international business area, international entrepreneurship, and emerging eco-innovation field through the embedded effectuation principles. The study embraces an inductive case study approach which involves 12 participants from international actors and members of BG firms in semi-structured interviews. Furthermore, the industrial context of the study revolves around the biocomposite industry and its network to view eco-innovation nuance. The research found that Eco-innovation technology competence becomes the available means to internationalize for BG firm. Moreover, it is concluded that the effectuation theory is reliable both to be used by researchers in analyzing the phenomenon and dominantly used by the entrepreneur in internationalizing their business in uncertain time such as the early stage of internationalization. BG firm utilizes the contingencies through a learning process iteratively but at a quick pace due to their alliance with the network, but the business form is more effectually transformed instead of incrementally changing and well-planned. The use of a formal causation approach was present yet limited during the process. The findings of this study add to the existing literature of internationalization by incorporating eco-innovation, as well as bridging the gap between eco-innovation, international business, and entrepreneurship literature.

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Löwe, Hannes [Verfasser], Andreas [Akademischer Betreuer] Kremling, Andreas [Gutachter] Kremling y Lorenzo Victor [Gutachter] De. "Engineering and Analysis of a Defined Mixed Culture of Pseudomonas putida and Synechococcus elongatus for Bioplastic Production / Hannes Löwe ; Gutachter: Andreas Kremling, Victor De Lorenzo ; Betreuer: Andreas Kremling". München : Universitätsbibliothek der TU München, 2018. http://d-nb.info/117558259X/34.

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Theron, Benjamin. "Nouveaux catalyseurs pour la synthèse par polymérisation par ouverture de cycle de polyesters biosourcés et biodégradables". Electronic Thesis or Diss., Bourgogne Franche-Comté, 2024. http://www.theses.fr/2024UBFCK002.

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Les recherches de catalyseurs pour la synthèse de nouveaux (co)polymères biosourcés et biodégradables ont conduit à l’émergence de nouvelles familles de complexes (salens, guanidines, phénoxy-imines...) ainsi qu’à une meilleure compréhension de leur mode de fonctionnement.Les travaux présentés dans ce manuscrit ont ainsi porté sur l’utilisation de nouvelles familles de complexes polyazotés π-conjugués phénoxy-amidines (FA) et biguanides pour la synthèse par ROP de polyesters biosourcés et biodégradables.L’implémentation de cette thématique dans notre équipe de rercherche ainsi que la mise en évidence du comportement unique et particulier de ces nouveaux catalyseurs sont présentées dans ce manuscrit.Dans un premier temps, les synthèses de nouveaux complexes phénoxy-amidines et phénoxy-imines analogues ont été réalisées. Une étude en ROP du lactide a d’abord été menée avec des complexes de zinc et d’aluminium FA. Certains de ces complexes se sont révélés capables de produire du PLA en utilisant des monomères de qualité industrielle contaminés par des quantités importantes d’acide lactique. Une étude comparative menée avec les complexes phénoxy-imines (FI) a montré que les complexes ne fonctionnent pas dans ces conditions plus dures.Les complexes de zinc porteurs de ligand bis(phénoxy-amidine) (FAlen), ont montré les activités en ROP du lactide les plus élevées alors que leurs analogues salen ne catalysent pas cette réaction de polymérisation.Des tests ont également été réalisés en ROP du lactide et de la butyrolactone avec de nouveaux catalyseurs biguanides mono- et bimétalliques zinc et aluminium. Le catalyseur de zinc biguanide monométallique a conduit à la meilleure activité jamais décrite pour un système monométallique de zinc
Research on catalysts for the synthesis of bio based and biodegradable (co)polymers has led to the emergence of new families of catalysts (salens, guanidines, phenoxy imines...) and a better understanding of their behavior. The work presented in this manuscript focuses on using new π-donors phenoxy amidines (FA) and biguanides complexes for the ROP of biobased and biodegradable polyesters.The implementation of this theme at the Dijon site, along with highlighting the unique and specific behavior of these new complexes, is presented in this manuscript.Initially, the synthesis of new FA and analogous phenoxy-imines complexes was carried out. Some of these complexes have been shown to produce polylactic acid (PLA) using industrial-grade monomers contaminated with significant quantities of lactic acid. A comparative study conducted with the parent phe-noxy-imine (FI) complexes, showed that they do not work under these degraded conditions. Zinc complexes with bis(phenoxy-amidine) ligands (FAlen) showed the highest activity in ROP of lactide, whereas their salen analogs do not catalyze this polymerization reaction.Tests were conducted on lactide and butyrolactone ROP using new mono- and bimetallic zinc and aluminum biguanide catalysts. The zinc biguanide catalyst produced the highest lactide ROP activity ever reported for a monometallic system

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Karlsson, Sandra. "Förseglingsegenskaper hos pappersförpackningar med konventionell plast och bioplast". Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-80707.

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Pappersbaserade förpackningar är ett område som växer snabbt. För att hålla ihop en förpackning och skydda dess innehåll är det nödvändigt mednågon form av förslutningsystem. I projektet har förslutningar i form av varmförseglingar studerats för olika sorters förpackningsmaterial. Vidvarmförsegling pressar två varma metallbackar ihop materialen vilket gör att en försegling bildas mellan dem. Hur stark en försegling blir beror påmaterialegenskaper och på de parameterinställningar som används vid försegling. Vilken analysmetod och vilka inställningar proverna analyseratsmed påverkar de resultat som erhålls. Studien inkluderade flexibla material för applikationer inom medicin och livsmedel samt styva material vilkavar svåra att analysera med de analysmetoder som fanns tillgängliga. Förseglingar gjordes i laboratoriemiljö och i kommersiellatillverkningsmaskiner för att undersöka om dessa kan jämföras. Experimenten visar bland annat att förseglingsegenskaperna varierar beroende påtyp av plast och papper, materialets tjocklek och ytvikt. Förseglingsstyrkan är också olika beroende på om den testas längs eller tvärs materialetstillverkningsriktning. Genom en stor mängd analyser har en strategi för hur olika material bör utvärderas arbetats fram.
Paperboard and paper based solutions are of rapidly increasing interest to the packaging industry. Packaging needs a sealing system to keep theproduct inside safe. One common type of sealing is heat sealing, i.e. the materials are placed between two hot sealing bars which are closedtogether to form a seal. The strength of such seals depend on the properties of the material and the settings during sealing. The test method and thesettings used when analysing samples do also influence the results. This study of sealing properties includes flexible material for medicalapplications and materials used in food applications, as well as stiff and thick materials used in food applications which are harder to analyse usingcurrent methods. Sealing properties are for some materials compared between seals made in commercial packaging machines and seals made in thelaboratory. The results from this study show that sealability is dependent on 1) what kind of paper and what kind of plastic are used; 2) thicknessand weight of the material; and 3) whether the test is performed in or cross machine direction. Finally, a method is proposed on how to evaluatedifferent kinds of materials based on data generated by this study.

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Johansson, Matilda. "Produktion av bakteriell cellulose genom användning av det symbiotiska förhållandet mellan bakterier och jäst som används vid Kombuchatillverkning". Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-23293.

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Different factors such as growing environmental awareness due to the increasing negative impact of persistent plastic wastes, the uncontrollable price variations of the raw material and the rapid depletion of reserves have increased the interest in research regarding polymers derived from renewable sources to replace petroleum-based materials. One of the earth’s most abundant macromolecules is cellulose. The production of cellulose from another resource replaces and reduces the demand from plants, the other resource being cellulose from a bacterial system. Bcaterial cellulose film were produced by fermenting apple waste (apple pomace) from cider production donated by Herrljunga Cider in Herrljunga, Sweden and expired fruit juice, produced by LoveJuice Indonesia, containing a mixture of fruits, mainly apple. As inoculum for the fermentations two different Kombucha cultures were used. To optimize the fermentation conditions, factors such as nitrogen source, sugar content, temperature, pH, surface area, sterilization of the substrate, culture condition and fermentation time was varied to obtain the desired result. The bacterial cellulose films were dried at 50-70 °C in an oven, air-dried or freeze-dried to evaluate the impact of drying technique on the final material. The behavior of the microorganism during fermentation was monitored by sampling and observation. The consumption rate of carbohydrates was analyzed using high performance liquid chromatography (HPLC). The properties of the obtained biofilms were analyzed using thermogravimetric analysis (TGA), tensile testing and determination of cellulose content in the obtained biofilms. Two different sugar concentrations (35 g/l and 70 g/l) and three different caffeine concentrations (0 g/l, 150 g/l and 225 g/l) as nitrogen source were investigated to determine the best condition. A control batch of conventional (black tea and 70 g/l table sugar) Kombucha was used as reference. The highest tensile strength (50 MPa) and thermal stability was observed in the biofilms with the highest yield that had been dried in oven. The biofilms obtained by fermenting apple pomace from the cider industry showed the highest tensile strength and highest thermal stability in comparison to fermenting expired fruit juice. The biofilm obtained by fermenting apple waste(sugar concentration 70 g/l) in combination with sterilizing the substrate without adding any nitrogen source, dried in an oven and purified using 0,1 M NaOH resulted in the highest tensile strength, highest thermal stability and the purest biofilm from a visual aspect. The highest yield was observed in the fermentation of apple pomace (sugar concentration 70 g/l) from the cider industry without sterilization of the initial media with an addition of nitrogen of approximately 450 mg/l). The optimal fermentation period was observed to be 14-15 days, at 25-28 °C under static conditions using a glass vessel with a diameter of 20 cm and an initial pH of 5,5.

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Roy, Rahul. "Bacteria - based self - healing mortar with bio - plastic healing agents : Comparative analysis on quantification and characterization of self-healing by various experimental techniques". Thesis, KTH, Betongbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-289227.

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Crack formation in concrete structures due to various load and non-load factors leading to degradation of service life is very common. Repair and maintenance operations are, therefore, necessary to prevent cracks propagating and reducing the service life of the structures. Accessibility to affected areas can, however, be difficult and the reconstruction and maintenance of concrete buildings are expensive in labor and capital. Autonomous healing by encapsulated bacteria-based self-healing agents is a possible solution. In this study, a novel bacteria-based healing agent was investigated in order to test the self-healing efficiency of the specimens in comparison to the commonly used healing agents made of lactic acid derivatives. (PLA). The novel integrated healing agent is a non-toxic, biodegradable dissolved inorganic carbon substrate derived from wastewater that has been used as an encapsulation material for spores of cohnii bacteria in the Bacillus gene family and for nutrients made up of yeast extract. This dissolved inorganic carbon substrate is a bioplastic made by the bacteria in wastewater known as alkanoate derivatives (AKD). To assess the effect of these healing agents on the mortar characteristics, quantification and characterization of the self-healing were conducted. The quantification of the self-healing efficiency was performed by various experimental techniques such as light microscopy, water permeability, chloride ion permeability, and thermogravimetric analysis whereas the material characterization was investigated by x-ray diffraction and environmental scanning electron microscope. Moreover, a statistical analysis was performed to study the correlation of self-healing efficiency between various experimental techniques. The incorporated dosages of healing agents adopted were 2.6% and 5% by weight of cement. Complete immersion in water was considered to be the condition of treatment of the specimen for healing at two separate periods of 28 and 56 days. The crack widths investigated were in the range of 0.04 to 0.8 mm. The quantification and characterization tests indicated that bacterial containing mortar series especially PLA and AKD at 5% dosage displayed a higher self-healing performance and an indication of precipitated calcium carbonate in the crack mouth. However, the results from the chloride migration test didn’t show any influence by the self-healing healing agents. Furthermore, the statistical analysis identified a major impact of the internal crack geometry on the difference in self-healing ratios, also in the cases where effective crack width is equal.
Sprickbildning i betongkonstruktioner p.g.a. olika laster och lastoberoende faktorer som leder till förkortning av livslängden är mycket vanligt förekommande. Reparation och underhåll är därför nödvändiga för att förhindra att sprickorna propagerar och reduceras konstruktionernas livslängd. Möjligheterna att komma åt de skadade partierna kan dock vara svåra och reparationerna är vanligen både arbetsintensiva och kostsamma. Självläkning med ingjutna bakteriebaserade, självläkande tillsatser är en möjlig lösning på problemet. I denna studie undersöktes en ny bakteriebaserat självläkande tillsats för att prova den självläkande förmågan i jämförelse med vanligt förekommande självläkande tillsatser av mjölksyrederivat (PLA). Den nya integrerade självläkande tillsatsen är en giftfri, biologiskt nedbrytningsbar, oorganisk kolsubstratslösning utvunnen ur avloppsvatten, en tillsats som har använts som ett inkapslingsmaterial för sporer från cohnii-bakterier från bacillussläktet och från näringsämnen framställda ur jästextrakt. Denna kolsubstratslösning är en bioplast framställd ur avloppsvatten och känd som alkanoatderivat (AKD). För att bestämma effekten av dessa självläkande tillsatser på cement bruks egenskaper genomfördes kvantifiering och karakterisering av självläkningen. Kvantifieringen av självläkningens effektivitet utfördes genom olika experimentella metoder såsom ljusmikroskopi, vattengenomsläpplighet, kloridjonstransport och termogravimetriska analyser medan materialkarakteriseringen utfördes med röntgendiffraktion och svepelektronmikroskop (ESEM). Vidare genomfördes en statistisk analys för att undersöka korrelationen mellan olika experimentella metoder. De doser av självläkande tillsatser som användes var 2,6 och 5 % av cementvikten. Fullständig nedsänkning i vatten ansågs vara den lämpligaste lagringen för självläkning under två olika tidsperioder på 28 respektive 56 dygn. De sprickbredder som studerades låg i intervallet 0.04 till 0.8 mm. Försöken kring kvantifiering och karakterisering indikerade att bruken innehållande bakterier, i synnerhet 5 % PLA och AKD, utvecklade en högre form av självläkande beteende och en förekomst av kalciumkarbonat i sprickspetsen. Resultaten från försöken kring kloridtransport visade emellertid inga tecken på någon effekt från de självläkande tillsatserna. Vidare identifierades i den statistiska analysen att inre sprickbildning har stor betydelse för självläkningseffekten även i fall där den effektiva sprickbredden är lika stor.

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38

Matsuura, Eri, Yan ye y Xiaoxuan He. "Sustainability Opportunities and Challenges of Bioplastics". Thesis, Blekinge Tekniska Högskola, Avdelningen för maskinteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2188.

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Bioplastics (BPs) can be defined as plastics made of biomass such as corn and sugarcane. These substances have been increasingly spotlighted as means to saving fossil fuels, reducing CO2 emission and plastic wastes. Biodegradability of BPs has been widely publicized in society and the demand for packaging is rapidly increasing among retailers and the food industry at large. However, there is little consensus on actual impacts of BPs production. This thesis therefore aims to identify current strengths and weaknesses and future threats and opportunities and leverage points for the bioplastics industry in a move towards sustainability?” The Strategic Life Cycle Management (SLCM) and Templates for Sustainable Product Development (TSPD) approaches were used to reveal current ecological and social impacts in relation to Sustainability Principles from the Framework for Strategic Sustainable Development. Various sustainability challenges and opportunities were identified. Most threats were in agricultural production and in the disposal of products. Compelling measures for the BP industry include: having a consensus in BPs applications based on strategic sustainable development, universal labelling and recycling systems for BPs, government strategic policies to encourage research into new technologies in improving biodegradability and energy efficiency in manufacturing.

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39

Sá, Fernando Luís de Góis Rodrigues de. "Separation and purification of microbial bioplastics". Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22681.

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Mestrado em Biotecnologia - Biotecnologia Industrial e Ambiental
Os polihidroxialcanoatos são poliésteres biodegradáveis produzidos por inúmeros organismos. Possuem características muito semelhantes às dos plásticos, apresentando-se como um possível substituto dos mesmos. Os PHAs são produzidos na forma de corpos de inclusão, sendo necessária a sua extração. Os surfactantes são compostos tensioativos capazes de extrair os PHAs, através da sua incorporação, e consequente saturação, nas membranas bacterianas, auxiliando na sua lise. Neste trabalho começou-se por testar a eficácia de uma variedade de surfactantes, e alguns líquidos iónicos, na extração de PHA de culturas mistas. O Tween 20 destacou-se dos restantes visto praticamente não apresentar acumulação de surfactante na amostra de PHA, tendo igualmente sido responsável pelo isolamento e análise do mesmo, de forma eficiente. Com este composto realizaram-se testes onde se variaram a quantidade de biomassa, a concentração de surfactante e o tempo de digestão. Quanto às concentrações de surfactante utilizadas, 50mM, 150mM, 250mM, 400mM e 500mM, os melhores rendimentos de extração (56-61%) foram conseguidos com menores concentrações de surfactante (50mM e 150mM). Com os tempos de digestão (2h, 4h, 6h, 8h e 14h) e com a quantidade de biomassa (0.3g e 0.8g), verificou-se que com quantidades e tempos mais reduzidos (4h e 0.3g) foi possível obter melhores ou semelhantes resultados aos obtidos com valores superiores de tempo e biomassa. O clorofórmio foi substituído pelo dimetil carbonato no passo de purificação, reduzindo bastante a toxicidade do processo. Foi também elaborada uma extração utilizando apenas digestão com surfactante, sem purificação, atingindo-se um rendimento de 16.17%. Para além dos semelhantes resultados obtidos neste trabalho, um novo processo foi testado e redesenhado para a extração de PHAs em culturas mistas, verificando-se até aqui uma redução dos custos e da toxidade do processo, com a possibilidade de remover totalmente o passo de solubilização do polímero num solvente orgânico.
Polyhydroxyalkanoates (PHA) are biodegradable polyesters produced by a variety of organisms. Their characteristics are very similar to those found on plastics, making them a viable replacement for this important product. Inside cells, PHA are produced under the form of inclusion bodies, and its extraction is required. Surfactants are compounds able to carry out PHA extraction by incorporating, and consequently saturating, the bacterial membrane, facilitating the lysis process. In this thesis, we begun by testing the extraction efficiency of a screening of surfactants, and some ionic liquids, on mixed cultures. Tween 20 stood out from the rest, as the PHA biofilm obtained was free from any surfactant and was possible to isolate and analyse the polymer efficiently. Using Tween 20 as extractive agent, more tests were carried out, where the amount of biomass, concentration of surfactant, and time of digestion were studied. As for the surfactant concentrations 50mM, 150mM, 250mM, 400mM e 500Mm, better extraction yields (56-61%) were achieved with lower concentrations (50mM and 150mM). As for digestion times (2h, 4h, 6h, 8h and 14h) and biomass quantity (0.3g and 0.8g), it was verified that with lower values and times (4h and 0.3g), results obtained were very similar, or better, than those obtained with overnight digestion and 0.8g of biomass. Chloroform was replaced by dimethyl carbonate, greatly reducing the process toxicity in the purification step. An extraction using solely surfactant digestion, without a purification step, was also performed, achieving an extraction yield of 16.17%. In addition to the similar yields obtained in this work, a new process was tested, and later redesigned, for PHA extraction in mixed cultures, with a reduction of costs and toxicity of the process, and with the future possibility of completely removing the step based on the solubilization and isolation of the polymer in an organic solvent.

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40

Hedin, Andreas. "Bioplastproduktion från skogsindustriellt avloppsvatten : En energiteknisk och ekonomisk utvärdering för att producera polyhydroxyalkanoater på Gruvöns Bruk". Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-79002.

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I framtiden kommer avfall att behöva hanteras cirkulärt och resurser tas om hand för att möta hårdare framtida miljökrav. Ett miljöproblem som lyfts de senaste åren är nedskräpning där plast ofta nämns som ett exempel. Plast är ett viktigt material och används i stora delar av samhället. Det är hållbart och har ett högt nedbrytningsmotstånd vilket har bidragit till materialets popularitet. Dock leder dess egenskaper till problem om materialet hamnar i naturen eller havet. Ett alternativ till konventionellt tillverkad plast som senare år har fått uppmärksamhet är bioplast. Ett sätt att tillverka bioplast är från polymerer som kallas polyhydroxyalkanoater (PHA). PHA är biologiskt lättnedbrytbara, biobaserade och förnyelsebara polymerer och benämns som framtidens polymerer av forskare. Polymererna kan tillverkas från mixade bakteriekulturer som bland annat hittas i skogsindustriella avloppsvatten. Fördelar med att använda en mixad istället för en monobakteriekultur är reducerade kostnader i produktionen. De höga kostnaderna för produktionen är en nackdel och lyfts fram som ett hinder för att en storskalig industriell produktion kan ske lönsamt enligt tidigare studier. Kostnaderna för extraktionen av polymererna utgör ungefär 70 % av de totala produktionskostnaderna. I det här arbetet har sex olika teoretiskt uppbyggda system som producerar färdiga PHA polymerer från skogsindustriellt avloppsvatten undersökts med Gruvöns bruks biologiska reningsanläggning, Multibio, som utgångspunkt. Systemen som undersöktes var kombinationer av olika sätt att fermentera avloppsvattnet och därefter extrahera polymererna. Målet var finna det system som var mest ekonomiskt försvarbart med ett syfte att analysera olika system som kan bidra till en ekonomisk hållbar tillväxt. För att beräkna flöden av massa och energi upprättades en beräkningsmodell i Matlab Simulink, där dagsdata från 2019 matades in. Resultaten från mass- och energianalysen importerades därefter till Microsoft Excel och en kalkyl byggdes. Resultaten visade att systemet med fermentering vid inloppstemperaturen på flödet och en kombination av högtryckshomogenisering och enzymextraktion producerade upp till 650 ton PHA per år och även generade en vinst på cirka 20 miljoner kronor om året. Med hjälp av nuvärdesmetoden itererades en högsta tillåten grundinvestering fram för att systemet ska vara avbetalat efter 15 år som slutade på cirka 150 miljoner kronor. I studien förekommer osäkerheter som efter analyser och diskussion är rekommenderade att utredas vidare som bland annat efterhanteringen av de nya kemikalier som uppstår med det nya systemet och indata på priser till kalkylen. Av studiens resultat dras slutsatsen att potential finns för att produktion av PHA från skogsindustriellt avloppsvatten kan ske med en ekonomisk hållbarhet men att fortsatta studier är nödvändiga på grund av osäkerheterna i arbetet.
In the future, waste will need to be handled in a circular manner and resources be taken care of to meet the tougher environmental requirements of the future. An environmental problem that has been highlighted in recent years is littering where plastics are often cited as an example. Plastic is an important material and is used in large parts of society. It is durable and has a high degradation resistance which has contributed to the material's popularity. However, its properties often lead to complications if the material ends up in nature or the ocean. An alternative to conventionally manufactured plastics that has received attention in recent years is bioplastics. One way to make bioplastics is from polymers called polyhydroxyalkanoates (PHA). PHAs are biodegradable, biobased and renewable polymers and are referred to as the “polymers of the future” by researchers. The polymers can be made from mixed bacterial cultures which can be found in forest industrial wastewater. Benefits of using a mixed rather than a monobacterial culture are the reduced costs in production. The high cost of production is a disadvantage and is highlighted as an obstacle to a large-scale industrial production being profitable according to previous studies. The cost of extraction of the polymer represents about 70% of the total production cost. In this work, six different theoretically constructed systems that produce ready-made PHA polymers from forest industrial wastewater have been investigated using Gruvön mill's biological wastewater treatment plant, Multibio, as a starting point. The systems investigated were combinations of different ways of fermenting the wastewater and then extracting the polymers. The goal was to find the system that was most economically defensible with the aim of analysing different systems that could contribute to economically sustainable growth. To calculate mass and energy flows, a model was established in Matlab Simulink, where daily data from 2019 were used. The results of the mass and energy analysis were then imported into Microsoft Excel and a spreadsheet was built. The results showed that the system of fermentation at the inlet temperature of the flow and a combination of high-pressure homogenization and enzyme extraction produced up to 650 tonnes of PHA per year and generated a yearly profit for about 20 million SEK. Using the present value method, the maximum allowable basic investment was iterated until the system would be paid off after 15 years, which ended at about 150 million SEK. The study contains uncertainties, that after analysis and discussion are recommended to be further investigated, such as the handling of the new chemicals that arise with the new system and input on prices for the calculations. The study concludes that there is potential for production of PHA from forest industrial wastewater with economic sustainability, but that further studies are necessary due to the uncertainties in the thesis.

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41

Farinha, Inês da Silva. "Optimization of bioplastics production from cheese whey". Master's thesis, FCT - UNL, 2009. http://hdl.handle.net/10362/2377.

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Dissertation presented in partial fulfillment of the requirements for the degree of Master in Biotechnology
Polyhydroxyalkanoates (PHAs) are polyesters produced by a variety of microorganisms. Due to the similarity of chemical and physical properties with the conventional plastics, and full biodegradability, PHAs constitute one of the best alternatives for synthetic polymers replacement. However, the production costs of these biopolymers are very high when compared to synthetic polymers production. One way to reduce the production costs is the utilization of low cost raw materials, such as industrial wastes and by-products as carbon source. An example of raw material is cheese whey, a by-product form cheese industry rich in lactose (4-5%). In this work, cheese whey was supplied to Escherichia coli strains harbouring the PHB synthesis genes from Cupriavidus necator for the production of poly(3hydroxybutyrate) (PHB). During this study, diverse reactor operating strategies were tested: feeding controlled by pH under oxygen limitation, feeding without oxygen limitation and continuous feeding. The best results were achieved in a fed-batch system with feeding controlled by pH and oxygen limitation, where 44.93% of PHB content,33.76 g/L of PHB concentration, 78.65 g/L of active biomass concentration and a volumetric productivity of 0.57 gPHB/L.h, were obtained.

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42

Ricci, Andrea. "Thermoplastic lignin esters as polymeric plasticizers for bioplastics". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/24906/.

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In this thesis, a sustainable and scalable process for modifying the structure of technical lignin to make it suitable for mixing with common bioplastics is studied. More specifically, this project deals with the development of a method of grafting fatty acids onto lignin. First, an updated state of the art concerning the processes for lignin production and its esterification is introduced and thoroughly discussed. Next, the materials and methods used to perform one-pot synthesis on lignin are described. The grafting process is initially optimized using a model reaction; afterwards, these conditions are adapted to technical lignin. The resulting process is also scaled up, overcoming unexpected issues due to mass and energy transfer. The modified lignins have been characterized through various thermal and analytical analyses (such as DSC, TGA and NMR), to provide a detailed description of their properties and structures. Finally, modified lignin was used to produce blends with commercial PLA as a proof of concept. As a matter of fact, this thesis is leading the basis for the fabrication of new-concepts materials based on plasticized lignin, aiming to conjugate sustainable industrially scalable processes and material performances.

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43

Tonuk, Damla. "Making bioplastics : an investigation of material-product relationships". Thesis, Lancaster University, 2016. http://eprints.lancs.ac.uk/78314/.

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This study explores how bioplastics come into being and are changing by focusing on the relationship between bioplastic materials and the products into which they are made. Bioplastics, which are types of plastics that are made from plant sources and/or can be decomposed by microbial activity, are a challenging set of materials not only because of their variety, but also because of the multitude of industries, actors and socio-technical arrangements involved in their making. I explore the different places in which bioplastics are made; in practices of categorising and standardising and so defining bioplastics, in production and the realisation of bioplastics in everyday life through their substitution for other materials, and in branding where bioplastics are made variously visible, as well invisible, as their particular qualities are enacted in specific material-product relationships. I draw conclusions about the nature of the relationship between materials and products, how they are separate but also intricately interconnected, at the same time acknowledging that what is named as a material and as a product is contingent upon the stakeholder in the production chain of materials and products. I detail the ways in which materials get shaped by and also shape the standardization and production infrastructures, interests of different actors, competitor materials, and values at stake within their interaction to specific products. The aim of my study is to open up new connections and pathways for the study of materials, as well as objects, within the social sciences.

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44

Pereira, Joana Sofia Marques. "Bioplastics production through mixed microbial cultures eco-engineering". Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/21085.

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Mestrado em Biotecnologia
Bioplastics have been the focus of interest as a sustainable alternative to conventional plastics. Among those, polyhydroxyalkanoates (PHA) can be highlighted, not only for their biocompatibility and biodegradability, but also because they can be produced by mixed microbial cultures (MMC) from agro-industrial wastes. This allows to substantially reduce the production costs and valorize alternative substrates. PHA have a wide range of characteristics according to their composition, which allows them to be used in many applications. The polymers characteristics can be manipulated through the control of several operational parameters during the production process. Production of PHA by MMC in this work was based in a three-stage process: acidification of a by-product of the paper industry, hardwood spent sulphite liquor (HSSL), selection of a PHA accumulating microbial culture and PHA production. The selection step occurred in a sequencing batch reactor (SBR), operated for 180 days, and whose conditions were changed in order to select for a PHA-accumulating culture and with good PHA volumetric production. Three pseudo-stationary states (PSS) were achieved after successive increases in the selective pressure, a clear indication that the MMC was able to adapt to the substrate and to the imposed conditions. In the last step of this work several accumulation assays were performed that allowed for the validation of the use of HSSL acidified under different conditions and Condensate (another byproduct of the paper industry) for PHA production. The best test performed achieved a maximum accumulation of 74.7% cdw and a volumetric productivity of 0.27 gPHA/L.h. This work allowed to show the potential of the use of PHA producing MMC as a way of valorization of agroindustrial byproducts and residues.
Os bioplásticos têm sido foco de interesse como alternativa sustentável aos plásticos convencionais. Entre os vários biopolímeros destacam-se os polihidroxialcanoatos (PHA), não só pela sua biocompatibilidade e biodegradabilidade, mas também porque podem ser produzidos por culturas microbianas mistas (MMC) a partir de resíduos agroindustriais. Desta forma é possível reduzir substancialmente o preço de produção destes polímeros e valorizar substratos alternativos. Os PHA apresentam características muito variadas de acordo com a sua composição, o que permite que sejam utilizados em diversas aplicações. As características do polímero podem ser manipuladas através do controlo de vários parâmetros operacionais durante o processo de produção. A produção de PHA por MMC neste trabalho foi feita com recurso a um processo em três fases: acidificação de um subproduto da indústria papeleira, o licor de cozimento ao sulfito ácido acidificado (HSSL), seleção de uma cultura microbiana acumuladora de PHA e produção de PHA. A seleção ocorreu num reator descontínuo sequencial (SBR), operado durante 180 dias, e cujas condições foram alteradas de forma a selecionar uma cultura acumuladora de PHA e com boa produtividade volumétrica de PHA. Três estados pseudo-estacionários (PSS) foram atingidos após sucessivos aumentos na pressão seletiva, uma indicação clara de que a MMC foi capaz de se adaptar ao substrato e às condições impostas. No último passo do trabalho foram realizados vários testes de acumulação que permitiram validar a utilização de HSSL acidificado em condições diferentes e Condensado (outro subproduto da índustria papeleira) como substratos para a produção de PHA. O melhor teste realizado apresentou uma acumulação máxima de 74.4% cdw e uma produtividade volumétrica de 0.27 gPHA/L.h. Este trabalho permitiu mostrar a potencialidade do uso de MMC produtoras de PHA como forma de valorização de subprodutos e resíduos agroindustriais.

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45

Luzhnica, Donjeta. "Bioplast : Ett hållbart förpackningsmaterial". Thesis, Högskolan i Gävle, Avdelningen för industriell ekonomi, industridesign och maskinteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-30044.

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46

Vodička, Juraj. "Biodegradace bioplastů v prostředí kompostu". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-413729.

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This master’s thesis focuses on biodegradation of polyhydroxybutyrate (PHB) and polylactic acid (PLA). The theoretical part discusses an origin, properties and applications of investigated biopolyesters, and so the enzymology of their biodegradation. The experimental part deals with biodegradation of these polymers in liquid medium using several pure thermophilic bacteial strains and controlled composting of these bioplastics. Amongst six tested thermophilic bacterial strains only one showed PHB-biodegradation activity – strain Schlegelella thermodepolymerans. No degradation degree of amorphous or semi-crystalline PLA was observed. Mainly disintegration of both forms of PLA articles was observed in compost environment, thus the abiotic mechanism of its decomposition was indicated. After 4 weeks of composting, the relative weight loss of 99 % and 63 % was detected in amorphous and semi-crystalline PLA respectively. On the contrary, the weight loss of PHB after 4 weeks of composting reached 36 %, moreover, a half decrease of molar mass was observed using SEC. The surface erosive mechanism of PHB-biodegradation was stated using SEM. By monitoring of esterase, lipase and protease activities, no influence on the compost by polymer presence was concluded at statistical significance.

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47

Guerra, Federica. "Exploring Tannins from wood biomass as bioadditives for bioplastics". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/24061/.

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Synthetic plastics are considered as the most important materials in the world. However, recent studies have demonstrated how their diffusion has raised also environmental issues, especially due to their low biodegradability and poor recycling process. In order to overcome these limitations, the scientific community has analysed the use of biopolymers. In particular, the polyhydroxyalkanoates (PHAs) have attracted a lot of interest, since they are produced by microorganisms and they are easily available. Biopolymers used at the industrial scale need to be formulated with additives to be fully responding in terms of physical-mechanical properties, processability, durability and more. However, the selection of additives for bioplastics is made complex by the restrictions to be followed and their impact on the environment is not always negligible. Several kinds of natural molecules have been recently proposed as functional additives for bioplastics, as the hydrolysable and condensed tannins which are waste-biomass derivatives having a functionality as aromatic antioxidants units, potential antibacterial activity and thermal stabilizers. The purpose of this thesis is to develop novel bio-based plastics by including tannins in their formulation, and to assess their overall effect on the bioplastic's properties. Hydrolizable tannins from chestnut wood coming from a research laboratory at the University of Padova, have been used. As bioplastic matrix, we selected polyhydroxyalkanoates (PHAs) for the emerging potential as feasible sustainable substitutes for both standard and technical plastic grades. In order to assess the best strategies for including tannin molecules in PHA matrices, three different approaches have been developed: 1- SOLUTION MIXING 2- MELT MIXING 3- EMULSION MIXING The amount of tannin in the formulation has been varied from 0 to 5% and the samples have been fully characterised in terms of thermal properties and UV absorption.

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48

Amini, Shahsavarani Arjang. "Improvement of the properties of novel bioplastics through reactive compatibilization". Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/14566.

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Bioplastics are emerging as most promising materials to replace oil based thermoplastics particularly in packaging. Bioplastics can mitigate and address concerns about the negative role of plastics in the environment creating pollution and depleting resources hence bioplastics can enable an innovative approach toward addressing these issues. However, manufacturing of bioplastic is still costly and their mechanical and thermal properties require extensive development. Therefore there has been substantial interest to improve processing and properties of bioplastics to diminish the environmental impacts caused by continuous use of synthetic polymers of petroleum origin. In this research, Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) or PHBV and Polybutylene succinate (PBS) composites and blends were developed to improve the properties of PHBV as the matrix polymer and hence produce a novel formulation for product development. Three approaches were studied in this work:  The effect of talcum powder as a nucleating agent and reinforcing filler.  The effect of oligomer chain extenders on miscibility, crystallinity, thermal and thermomechanical, mechanical and morphological properties of PHBV/PBS blends.  The effect of acrylic core-shell impact modifier on crystallinity, thermal and thermomechanical, mechanical and morphological properties of PHBV were also evaluated. All the above scientific approaches have been studied. It was noticed that talc can change the sluggish crystallinity of PHBV. Talc enhances nucleation of PHBV in the composites which leads to a faster crystallization rate. The heat distortion temperature, crystallinity and the modulus of PHBV/talc composite were also increased. In the presence of the chain extender (CE) the miscibility conditions of PHBV/PBS blends were changed. The results were supported by calculation of the activation energies. The elongation at break and tensile strength of PHBV/PBS/Chain extender blends increased indicating miscibility change. The possible reaction mechanism between PHBV, PBS and CE are proposed and the results supported by using FTIR. Immiscibility results of the PHBV/PBS blends are supported by SEM images. Addition of the impact modifier to PHBV reduced the crystallization rate and prolonged crystallization time. It has been found that the shell of impact modifier (PMMA) is partially miscible with PHBV. The absorbed impact energy is improved by the impact modifier but the improvement was not as satisfactory as results noted for PLA. The SEM images showed the average fine dispersion of different sized particles inside the matrix.

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Duangphet, Sitthi. "Extrusion foaming of bioplastics for lightweight structure in food packaging". Thesis, Brunel University, 2012. http://bura.brunel.ac.uk/handle/2438/7350.

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This thesis reports the systematic approaches to overcome the key drawbacks of the pure PHBV, namely low crystallisation rate, tensile strength, ductility, melt viscosity, thermal stability and high materials cost. The physical, mechanical, thermal, and rheological properties of the pure PHBV were studied systematically first to lay a solid foundation for formulation development. The influence of blending with other biopolymers, inclusion of filler, and chain extender additives in terms of mechanical properties, rheology, thermal decomposition and crystallization kinetics were then followed. Creating lightweight structures by foaming is considered to be one of the effective ways to reduce material consumption, hence the reduction of density and morphology of PHBV-based foams using extrusion foaming technique were studied comprehensively in terms of extrusion conditions (temperature profiles, screw speed and material feeding rate) and the blowing agent content. The material cost reduction was achieved by adding low-cost filler (e.g. CaCO3) and reduction of density by foaming. The thermal instability was enhanced by incorporation of chain extender (e.g. Joncryl) and blending with a high thermal stability biopolymer (e.g. PBAT). The polymer blend also improved the ductility. Adding nucleation agent enhanced the crystallization rate to reduce stickiness of extruded sheet. The final formulation (PHBV/PBAT/CaCO3 composite) was successfully extruded into high quality sheet and thermoformed to produce prototype trays in an industrial scale trial. The effect of the extrusion conditions (temperature profiles, screw speed and material feeding rate) and the blowing agent content are correlated to the density reduction of the foams. 61 and 47 % density reduction were achieved for the commercial PHBV and the PHBV/PBAT/CaCO3 composite respectively and there exists further scope for more expansion if multiple variable optimisation of the conditions are carried out.

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DOLGHI, Sandro Martins. "Avaliação de implantes de polimetilmetacrilato (PMMA) para procedimentos de bioplastia". Universidade Federal de Campina Grande, 2014. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/347.

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Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-09T18:16:27Z No. of bitstreams: 1 SANDRO MARTINS DOLGHI - DISSERTAÇÃO PPG-CEMat 2014..pdf: 1349252 bytes, checksum: 7e20e2840dc2a5d2e873cd9b77ed0100 (MD5)
Made available in DSpace on 2018-04-09T18:16:27Z (GMT). No. of bitstreams: 1 SANDRO MARTINS DOLGHI - DISSERTAÇÃO PPG-CEMat 2014..pdf: 1349252 bytes, checksum: 7e20e2840dc2a5d2e873cd9b77ed0100 (MD5) Previous issue date: 2014-12-19
O culto à beleza está em evidência no Brasil e no mundo, levando ao crescente aumento de técnicas e procedimentos para corrigir defeitos estéticos e minimizar os efeitos do envelhecimento. Diversas substâncias preenchedoras com fluidos de alta viscosidade ou partículas de polímeros em suspensão têm sido utilizadas em larga escala em procedimentos cosméticos e correção de lipodistrofia de pacientes HIV positivos, submetidos à terapia antirretroviral de alta atividade. O uso de polimetilmetacrilato (PMMA) como substância de preenchimento dérmico tem crescido vertiginosamente, assim como o número de reações adversas decorrentes de seu uso. O PMMA vem sendo utilizado, amplamente como matéria prima na fabricação de diversos dispositivos e produtos médicos desde a década de 40, especialmente em função de sua biocompatibilidade, entretanto, ainda há carência de informações e estudos sobre migração e resposta inflamatória das substâncias comercializadas no Brasil para fins de preenchimento dérmico. Este trabalho teve como objetivo avaliar as características físico-químicas de implantes de PMMA comercializados no Brasil para procedimentos de bioplastia, em três apresentações comerciais do produto com diferentes concentrações, visando delimitar limites aceitáveis para fins de registro destes produtos na Agência Nacional de Vigilância Sanitária (Anvisa), com foco na segurança sanitária. As amostras foram caracterizadas por Difração de Raios X (DRX), Espectroscopia na região do infravermelho com transformada de Fourier (FTIR), Microscopia Eletrônica de Varredura (MEV), Espectroscopia por Energia Dispersiva de Raios X (EDS), análise de Calorimetria Exploratória Diferencial (DSC), caracterização por Microscopia Óptica (MO). A técnica de DRX mostrou comportamento semicristalino do PMMA. Com a técnica de FTIR constatou-se os grupos funcionais presentes nos implantes. Por meio das técnicas de MO e MEV foi possível perceber a não homogeneidade em relação ao tamanho das microesferas de PMMA. Pôde-se concluir com os resultados de DSC que o pico endotérmico aumentou de acordo com as variações de concentração do PMMA. A partir dos dados obtidos neste trabalho constata-se que o consumidor está sujeito a riscos, visto que a irregularidade das superfícies e variações nos tamanhos das microesferas pode ocasionar reações adversas, em função da fagocitose das microesferas com tamanho inferior a 20 μm. O crescente uso das técnicas de preenchimento com implantes de PMMA, bem como sua indicação para uso em demais especialidades da medicina, o coloca como material a ser ainda amplamente estudado nas mais diversas aplicações do produto na área médica.
The cult of beauty is in evidence in Brazil and in the world, leading to increasing techniques and procedures to correct aesthetic defects and minimize the effects of aging. Several dermal fillers with high viscosity or polymer particles in suspension fluids have been used in large scale in cosmetic procedures and lipodystrophy correction of HIV-positive patients undergoing HAART activity. The use of polymethylmethacrylate (PMMA) as dermal filler substance has grown dramatically, and the number of adverse reactions arising from its use. PMMA has been used widely as a raw material in manufacturing various medical devices and products since the 40s, especially due to its biocompatibility, however, there is still a lack of information and studies on migration and inflammatory response of substances marketed in Brazil dermal filler purposes. This study aimed to evaluate the physical and chemical characteristics of PMMA implants sold in Brazil for bioplasty procedures in three commercial presentations of the product with different concentrations, in order to delimit acceptable limits for registration of these products at ANVISA, with focus on security health. The samples were characterized by X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Spectroscopy Energy Dispersive X-ray (EDS) analysis of Differential Scanning Calorimetry (DSC), characterized by Optical Microscopy (OM). The XRD technique showed semi-crystalline behavior of PMMA. FTIR technique found the functional groups present on the implants. Through OM and SEM techniques we saw the inhomogeneity relative to the size of the PMMA microspheres. One can conclude from the results of the DSC endothermic peak increased in accordance with changes in the concentration of PMMA. From the data obtained in this study it appears that the consumer is subject to risks as uneven surfaces and variations in size of the microspheres can cause adverse reactions, depending on the phagocytosis of microspheres with size less than 20 microns. The increasing use of technical fill with PMMA implants, as well as indications for use in other specialties of medicine, places it as material to be still widely studied in various product applications in the medical field.

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