Dissertations / Theses on the topic 'Plastics Plastics Extrusion process'
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Lam, Ying. "Quantification of dynamic mixing characteristics during polymer extrusion." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B36540869.
Full textLam, Ying, and 林瀅. "Quantification of dynamic mixing characteristics during polymer extrusion." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B36540869.
Full textWang, Xinting. "NEW SYSTEMS FROM THE FORCED ASSEMBLY CO-EXTRUSION PROCESS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1607104088439343.
Full textShishesaz, Mohammad Reza. "Structure-property relationships in extruded plastics foams." Thesis, Brunel University, 1989. http://bura.brunel.ac.uk/handle/2438/5404.
Full textHurysz, Kevin Michael. "Paste mechanics for fine extrusion." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/19424.
Full textSabol, Edward A. "The development of a dual extrusion blending process and composites based on thermotropic liquid crystalline polymers and polypropylene." Thesis, Virginia Tech, 1994. http://hdl.handle.net/10919/40650.
Full textArroyo, Huayta Carlos Alberto, and Raimundis Edward Sebastian Cruces. "Modelo para mejorar la eficiencia en el área de extrusión de una pyme manufacturera del sector plástico basado en SMED, Mantenimiento Autónomo y 5s." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/651811.
Full textIn the current context, Peruvian SMEs that belong to the plastic sector have an indicator of installed capacity utilization of around 71.45%. This measures the degree of use of production potential, which is diminished by efficiency problems. In the company under study this indicator is below the sector average, with a low efficiency of 78%, which is caused by breakdowns, reprocesses and setup times generated in the extruder machines. In this sense, this article proposes a model to improve efficiency in the extrusion area consisting of the integrated application of Lean Manufacturing tools: 5s, SMED and autonomous maintenance. The first one is used as a support tool for the execution of SMED and autonomous maintenance. The SMED tool can reduce the configuration time while the autonomous maintenance had as a reduction the amount of reprocesses and breakdowns in the extrusion process. This model was validated by implementing a pilot of the solution proposal. The results obtained were the increase in availability in 3% and quality in 3%. These results together represent an increase in efficiency from 78% to 83%.
Trabajo de investigación
Macauley, Nicola Jayne. "Extrusion and thermoforming of polypropylenes." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337017.
Full textZhao, Jianhong. "Solid state extrusion of polymers through convergent-divergent dies." Thesis, Loughborough University, 1991. https://dspace.lboro.ac.uk/2134/22079.
Full textRongzhi, Huang. "MULTILAYER CO-EXTRUSION AND TWIN-SCREW COMPOUNDING OF POLYMERIC ELASTOMER SYSTEMS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1404864078.
Full textBerkery, Daniel J. (Daniel John). "Process monitoring for plastics injection molding." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12746.
Full textIncludes bibliographical references (leaves 196-197).
by Daniel John Berkery.
M.S.
Uvieghara, Mathias N. "The Effect of Deborah Number and Aspect Ratio on the Film Casting of LLDPE Melts." Fogler Library, University of Maine, 2004. http://www.library.umaine.edu/theses/pdf/UviegharaMN2004.pdf.
Full textHandlos, Agnita A. "The processing of microcomposites based on polypropylene and two thermotropic liquid crystalline polymers in injection molding, sheet extrusion, and extrusion blow molding." Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06062008-164735/.
Full textChan, David Tai-Wai. "Analysis of molecular orientation and internal stresses in plastic sheet extrusion process /." The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487596307358216.
Full textParpart, Dawn Allison. "PET/nylon 66 polymer blends and carpet recycling." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/9139.
Full text林肖明 and Chiu-ming Lam. "Visualization studies on the dynamic processing characteristics of conventional full-flighted and barrier type single-screws." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31222845.
Full textNelson, Burke I. (Burke Irving). "Control of a polypropylene visbreaking process using an in-line process rheometer." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28499.
Full textThe rheometer was used as a viscosity sensor to provide feedback control for a polypropylene visbreaking process. A first order plus dead time model was used to model the process and the rheometer together, and typically had dead times of less than 60 s and a first order time constant of 15 s. Gain scheduling was incorporated into minimum variance and proportional-integral controllers to achieve closed-loop settling times of 200 s for viscosity setpoint changes and process disturbances.
De, Kock Willem Johan. "Numerical simulation of the plastics injection moulding process." Doctoral thesis, University of Cape Town, 1994. http://hdl.handle.net/11427/18307.
Full textYang, Yi. "Injection molding control : from process to quality /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CENG%202004%20YANG.
Full textIncludes bibliographical references (leaves 218-244). Also available in electronic version. Access restricted to campus users.
Barnes, Christopher Mark. "The cooling and solidification of thermoplastic polymers : an experimental and theoretical study of the cooling and solidification of thermoplastic polymers in various blow moulding and pipe extrusion situations." Thesis, University of Bradford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236460.
Full textHe, Fugui. "Modeling and process control of ultrasonic welding of plastics." Connect to resource, 1992. http://rave.ohiolink.edu/etdc/view.cgi?acc%5Fnum=osu1244134423.
Full textHuang, Keyuan. "Decrosslinking of Crosslinked Polyethylene via Ultrasonically Aided Extrusion." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1428160856.
Full textFinniss, Adam. "A parametric study of microcellular ABS foam production in the injection molding process." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5998.
Full textTitle from document title page. Document formatted into pages; contains xiii, 101 p. : ill. (some col.). Includes two zip files of TIF images. Includes abstract. Includes bibliographical references (p. 93-94).
Sanyal, Yoddhojit 1969. "Synthesis and analysis of a microcellular plastics extrusion system for insulation of fine wires." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50529.
Full textIncludes bibliographical references (leaves 138-140).
This thesis deals with analytical and experimental work performed on the extrusion of microcellular plastics with cell sizes of 20 microns or less and cell densities of about a billion cells per cm3. An analytical model of cell nucleation and cell growth during extrusion was developed. This model predicts the nucleation rate by taking into account Gibbs free energy change due to phase separation, as well as surface energy, in binary systems (such as polymer/gas mixtures). The cell growth kinetics during extrusion is also studied under some limiting cases. The analysis shows that due to the simultaneous occurrence of cell nucleation and cell growth during extrusion, these two phenomena are coupled and compete with each other for the gas dissolved in the polymer. With the aid of this model the important extrusion parameters affecting the microstructure of the foam were identified. An order-of-magnitude prediction of cell size, cell density and foam void fraction were made based on realistic numerical values of these parameters. The next phase of the project consisted of using the analytical model and Axiomatic Design Theory to design a tandem extrusion system for wire coating. Satisfaction of the Independence Axiom showed that the process was controllable. Preliminary analysis of the Information Axiom indicated that the system would be stable. Experiments were performed over a range of conditions to determine their effects on the final wire insulation diameter and capacitance. The experimental results were compared to the analytical predictions to further verify the validity of the model as well as to determine its limitations.
by Yoddhojit Sanyal.
Sc.D.
Cumberland, D. J. "The effects of process variables on the characteristics of compacted plastic powders." Thesis, Queen's University Belfast, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317108.
Full textNugent, Paul James. "A study of heat transfer and process control in the rotational moulding of polymer powders." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317138.
Full textOzden, Sedat. "Influence of process-induced stresses on the mechanical behaviour and dimensional stability of thermoplastic injection mouldings." Thesis, University of Ulster, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386074.
Full textBarkley, David. "Instrumentation of impact testing and evaluation of fibre reinforced injection moulded thermoplastics by process-structure-properties correlation." Thesis, Open University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328827.
Full textAlemaskin, Kirill. "ENTROPIC MEASURES OF MIXING IN APPLICATION TO POLYMER PROCESSING." Case Western Reserve University School of Graduate Studies / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=case1098397260.
Full textBates, Philip J. "Improving long-fibre compounding via a novel thermoplastic pultrusion process." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59584.
Full textExperimental pultrusion studies using polypropylene indicate that alternating concave (collecting) and convex (spreading) contoured pins promote superior resin impregnation compared to conventional cylindrically shaped pins. A mathematical model describes the necessary convex pin contour and was used to fabricate the convex pins employed in the research. Pins thus designed promote uniform filament spreading across the wide convex contour which in turn favours good resin impregnation.
Bates, Philip J. "Melt impregnation of glass roving in a thermoplastic pultrusion compounding process." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41328.
Full textThis research reports on the effect of several key pultrusion compounding parameters (roving pulling speed, number and diameter of pins, melt temperature and initial roving tension) on the impregnation of nylon 6.6 melt into glass roving. The interlaminar shear strength of pultruded strands and compression moulded test bars, as well as optical microscopy, void fraction measurements and injection moulded specimen physical properties are used to quantify impregnation. Simple mathematical models have been developed to simulate the effect of processing parameters on melt impregnation. Good qualitative agreement between the model and experimental data is observed.
Repka, Michael Andrew. "Physical-mechanical and chemical properties of topical films produced by hot-melt extrusion /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
Full textJoubert, Francois. "Rapid Tooling and the LOMOLD Process." Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1078.
Full textDoshi, Shailesh R. "A novel coextrusion process for the manufacture of short fiber-reinforced thermoplastic pipe /." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72817.
Full textDuncan, Stephen R. "The cross directional control of a web forming process." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/8726.
Full textGarland, Chrystal A. "Effect of manufacturing process conditions on the durability of pultruded vinyl ester/glass composites." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1774.
Full textTitle from document title page. Document formatted into pages; contains x, 125 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 83-86).
Sebio, Leonard. "Desenvolvimento de plastico biodegradavel a base de amido de milho e gelatina pelo processo de extrusão : avaliação das propriedades mecanicas, termicas e de barreira." [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255879.
Full textTese (doutorado)- Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-03T16:41:50Z (GMT). No. of bitstreams: 1 Sebio_Leonard_D.pdf: 5261418 bytes, checksum: c5f42d63b358e2b0af36c89bdbdd0259 (MD5) Previous issue date: 2003
Resumo: Devido ao crescente acúmulo de lixo proveniente de plásticos sintéticos, agredindo o ecossistema, diferentes estratégias estão sendo seguidas com o intuito de procurar diminuir essa agressão através da prevenção, redução, reciclagem, valorização química dos materiais sintéticos e especialmente oo uso de polímeros biodegradáveis. O uso de amido como materiais termoplásticos é promissor devido principalmente à disponibilidade natural desse produto, que é extraído de uma fonte inesgotável de matérias-primas (cereais, raízes, tubérculos, etc.). No entanto, as blendas não são totalmente biodegradáveis. Nessa ótica a presente pesquisa envolveu o uso de processo de extrusão termoplástica de dupla rosca e uma matriz retangular apropriada para produzir materiais laminados termoplastificados biodegradáveis a base de amido e gelatina plastificados por glicerol e água susceptíveis de serem moldados na forma de descartáveis, etc. Foi empregada a metodologia de superfície de resposta (MSR) para estabelecer modelos matemáticos preditivos baseados em Modelo Central Composto Rotacional (CCDR), num planejamento fatorial completo 23 de 5 níveis e de 3 variáveis independentes, a saber as concentrações de gelatina (50,0; 100,0, 150,0 g/g base úmida), de glicerina (50,0, 100,0, 150,0 g/g) em 1000g da blenda e umidade (30, 35, 40 %). As respostas obtidas das combinações 2 a 2 dos 3 fatores foram avaliadas considerando as propriedades mecânicas de tração e de barreira dos laminados termoplásticos obtidos após extrusão, tais como: a Resistência Máxima à Tração, Percentagem de Alongamento, Elasticidade (Modulo de Young), Permeabilidade ao vapor de água e Índice de desintegração em meio aquoso. Foi em seguida, desenvolvida uma metodologia matemática de otimização de ensaios que permitiu a partir de uma fórmula de combinação de melhores respostas, escolher 6 ensaios principais entre os 18 do delineamento. Após escolher as amostras de melhores propriedades foram avaliadas as ropriedades fisico-químicas e morfológicas, a saber: Microscopia Eletrônica de varredura (MEV), Estimativa de Condições de Armazenamento, Absorção de Água, Difratometria de Raios-X e Índice de Cristalinidade Relativa. Para observar o comportamento térmico dos laminados, avaliou-se as seguintes propriedades térmicas: Condutividade Térmica, Análise Termogravimétrica (TGA), Análise Térmica Dinâmica Mecânica (TDMA) e Calorimetria Diferencial de Varredura (DSC). As propriedades mecânicas foram principalmente influenciadas pelas concentrações de gelatina e de glicerol na avaliação dos laminados termoplásticos que apresentaram valor médio de resistência máxima à tração de 4,87 MPa; com valor máximo de 12,62 MPa; valor médio de porcentagem de alongamento de 46,46 % com máximo em 81,58% e valor médio de Módulo de Elasticidade de 160,70 MPa com máximo em 568,49 MPa. Quanto à permeabilidade ao vapor de água, apesar de ser influenciada exclusivamente pela concentração de glicerol, apresentou uma pequena variabilidade, pois o menor valor foi próximo do maior valor. Enquanto que o índice de desintegração em água foi dependente das concentrações de gelatina e do plastificante, onde foi observado que quanto menores ambas as concentrações, menor a desintegração. Avaliando o comportamento dos laminados em condições ambientais simuladas, verificou-se que alguns não sofreram alterações nas suas propriedades durante 25 dias de armazenamento a 65 e 75 % de UR. Os resultados de microscopia Eletrônica de Varredura indicaram que as diversas formulações empregadas em diferentes ensaios provocaram alterações na morfologia da matriz polimérica. As concentrações de gelatina e de glicerol influenciaram a cristalinidade dos laminados onde o laminado controle mostrou ser mais cristalino que os laminados dos ensaios formulados. O valor da condutividade térmica dos laminados revelou-se maior que o dos materiais sintéticos. Na degradação térmica, observou-se uma estabilidade até cerca de 230 oC quando iniciou-se a perda de massa observada através da termogravimetria, enquanto que as transições vítreas determinadas através de DMTA e DSC foram dependentes dos componentes das formulações dos ensaios e do tempo de armazenamento
Abstract: Due to the increasing accumulation of synthetic plastic rubbish, damaging the ecosystem, various strategies are being followed aimed at decreasing this aggression by way of prevention, reduction, recycling and chemical valorization of the synthetic materials, and especially by the use of biodegradable polymers. The use of starch to make thermoplastic materials is promising, due principally to the natural availability of the product, which is extracted from an endless stock of raw materials (cereals, roots, tubers etc.). However, the blends are not completely biodegradable. Thus this research involved the use of twin screw thermoplastic extrusion with an appropriate rectangular matrix, to produce biodegradable thermoplastic laminated materials based on starch and gelatin and plastified by glycerol and water, capable of being molded into the form of discardable products etc.. Response Surface Methodology (RSM) was used to establish predictive mathematical models based on the Central Compound rotational Design (CCRD) in a 23 complete factorial plan with 5 levels and 3 independent variables, these being the gelatin (50.0; 100.0; 150.0 g/g, wet basis) and glycerin (50.0; 100.0; 150.0 g/g, wet basis) concentrations in 1000g of mix, and the moisture content (30, 35, 40%). The responses obtained to the 2 x 2 combinations of the three factors were evaluated, considering the barrier and strain mechanical properties of the thermoplastic laminates obtained after extrusion, such as: Maximum resistance to strain, Percentage of stretching, Elasticity (Young's modulus), Water vapor permeability and the disintegration index in an aqueous medium. Mathematical methodology to optimize the trials was then developed which allowed one to choose the 6 main trials from the total of 18 from the design using a combination formula of best responses. After choosing those samples showing the best properties, the physical, chemical e morphological properties were evaluated using the following techniques: scanning electron microscopy (SEM), an estimate of the storage conditions, water absorption, X-ray diffraction and relative crystallinity index. The following thermal properties were evaluated in order to observe the thermal behavior of the laminates: Thermal Conductivity, Thermogravimetric analysis (TGA), Thermal Dynamic Mechanical analysis (TDMA) and Differential Scanning Calorimetry (DSC). The mechanical properties of the thermoplastic laminates were mostly influenced by the gelatin and glycerol concentrations, presenting a mean value for maximum resistance to strain of 4.87 MPa and a maximum value of 12.62 MPa; a mean value for % stretching of 46.46% with a maximum of 81.58% and a mean value for the Young's Modulus of 160.70 Mpa with a maximum of 568.49 MPa. With respect to water vapor permeability, despite being influenced exclusively by the glycerol concentration, this presented only slight variation, with the smallest value being similar to the largest value, whilst the disintegration index in water was dependant on both the gelatin and plastifier concentrations and the smaller the concentrations of these two concentrations, the smaller the disintegration. An evaluation of the behavior of the laminates under simulated environmental conditions, showed that some of them presented no alterations in their properties during 25 days of storage at 65 and 75% RH. The SEM results indicated that several of the various formulations used in the different trials caused alterations in the morphology of the polymeric matrix. The concentrations of gelatin and glycerol influenced the crystallinity of the laminates, the control laminate being more crystalline than those formulated in the trials. The Thermal Conductivity of the laminates was shown to be greater than that of the synthetic materials. For thermal degradation, stability was observed at about 230°C, point at which the materials started to loose mass as observed by the Thermogravimetric analysis, whilst the vitreous transitions determined by TDMA and DSC were dependant on the components of the trial formulations and storage time
Doutorado
Doutor em Tecnologia de Alimentos
Wen, Szu-sheng 1971. "Advances in on-line ultrasonic monitoring of injection molding process." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29784.
Full textA high-performance buffer rod is fabricated and calibrated as a new type of ultrasonic temperature probe to measure temperature during the extrusion process. The temperature obtained using the ultrasonic technique is comparable with calibrated conventional thermocouples. Comparison between ultrasonic sensors and conventional pressure and temperature probes is also discussed in this study.
Fung, Ka Tsai. "A capacitive transducer for process and quality monitoring in injection molding /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?CENG%202006%20FUNGK.
Full textGao, Xiang. "Ultrasound Assisted Extrusion and Properties of Polycarbonate/Carbon Nanotubes Composites and Cast Films." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1493394163570255.
Full textNovák, Jakub. "Návrh a realizace vytlačovací hlavy a návazných členů pro vytlačování kruhových plastových profilů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230993.
Full textArroyo-Huayta, Carlos, Sebastian Cruces-Raimudis, Gino Viacava-Campos, Claudia Leon-Chávarri, and Daniel Aderhold. "Model to improve the efficiency in the extrusion area in a manufacturing sme of the industrial plastic sector based on smed, autonomous maintenance and 5s." Springer, 2021. http://hdl.handle.net/10757/656029.
Full textAt present, companies in the Peruvian plastic sector have an average capacity utilization indicator of 71.45%. However, in Peru many SMEs are with 50% well below this indicator. After a study performed in a representative company of the Peruvian plastic sector, the causes of low efficiency in resource utilization were determined through a problems tree and a Pareto analysis. These causes are failures, reprocesses and Setup times in the extrusion machines, taking around 1008 h a year to solve these problems. This article proposes a model to improve efficiency, integrating Lean Manufacturing tools such as 5s, SMED, and autonomous maintenance. The first one was used as a support tool, while SMED was used to reduce the configuration time and autonomous maintenance to reduce the failures number and the reprocesses number. The model was validated through a case study, obtaining as results the reduction of the setup time by 50%, breakdowns by 50% and reprocesses by 60%.
Varela, Alfredo E. (Alfredo Enrique). "Estimation and control of part weight and relevant process parameters in injection molding of amorphous thermoplastics." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40273.
Full textMeasuring internal polymer temperature profiles in the injection mold cavity during molding is extremely difficult. This work presents a method which combines measurements of cavity surface temperatures, cavity pressure, and on-line calculations for estimating temperature profiles inside the cavity. These profiles are then used to estimate the bulk polymer temperature. Fitting the cycle-to-cycle values of bulk polymer temperature and peak pressure to a Tait equation of state yields a model to predict part weights.
The part weight is controlled through the use of a control strategy for the cavity pressure and the part weight model, together with the on-line estimation of the bulk temperature. A self-tuning algorithm with an observer is employed for controlling the cavity pressure time profile to a set point trajectory. The dynamics and control of the bulk temperature are also studied.
SHAKYA, BIKRAM D. "PYROLYSIS OF WASTE PLASTICS TO GENERATE USEFUL FUEL CONTAINING HYDROGEN USING A SOLAR THERMOCHEMICAL PROCESS." University of Sydney, 2007. http://hdl.handle.net/2123/1709.
Full textGlobal warming and diminishing energy supplies are two major current concerns. Disposal of plastic wastes is also a major concern. The aim of this research is to address these three concerns by developing a solar powered process, using waste plastics as fuel to generate energy. Research into: i) solar concentrators for high temperature thermochemical processes, and ii) pyrolysis/gasification of waste plastics has been separately reported in the literature. In this study the aim was to bring these fields of research together to design a solar receiver-reactor suitable for the production of a synthesis gas, consisting of hydrogen, from waste plastics. To achieve this aim, studies of plastic decomposition behaviour using the thermal analysis method known as thermogravimetric analysis were conducted. Solar concentrators and their potential to be used for thermochemical processes were also studied. Firstly, the thermal decomposition behaviour of common plastics, namely low density polyethylene (LDPE), high density polyethylene (HDPE), polyethylene terephthalate (PET) and polyvinyl chloride (PET), were studied using thermogravimetry at heating rates of 5, 10, 20, 50 and 100 ºC/min. The kinetic parameters for the decomposition were determined from these experiments. Secondly, a simple solar receiver-reactor in which the plastic decomposition could be achieved was designed. The solar receiver-reactor designed was a quartz tube reactor which can be placed in the focus of a dish type parabolic concentrator capable of generating up to 3 kW in the focus of diameter 50 mm. The thermogravimetric analysis of plastic samples showed that LDPE, HDPE and PET have a single-step decomposition, whereas PVC has a two-step decomposition. The first step was related to the release of hydrogen chloride from the PVC and the second step was related to the release of hydrocarbon from the polymer backbone. If PVC is pretreated to release HCl it can be mixed with other plastics for a single step decomposition. It is likely that a single step plastic decomposition can be achieved in a directly irradiated solar receiver-reactor to generate useful gases consisting of hydrogen.
Pandey, Vivek. "Extensional Mixing Elements for Improved Dispersive Mixing in Extrusion Operations." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1591698465031928.
Full textSanchez, Urbina Israel. "Optimizing flow of plastic PBT with 45% glass and mineral fiber reinforcement in an injection over mold process using Taguchi, CPk and mold flow simulation software approaches." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
Full textChongwatpol, Narongsawas. "Implementing continuous process improvement methods in a mid-size plastic company." Menomonie, WI : University of Wisconsin--Stout, 2006. http://www.uwstout.edu/lib/thesis/2006/2006chongwatpoln.pdf.
Full textCengiz, Filiz. "Preparation And Characterization Of Recycled Polypropylene Based Nanocomposites." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609873/index.pdf.
Full text15A, Cloisite®
25A and Cloisite®
30B were used as organoclays, and ethylene-methyl acrylate-glycidyl methacrylate (E-MA-GMA) and maleic anhydride grafted polypropylene (PP-MAH) were used as compatibilizers. The effects of additive concentrations, types of organoclays and compatibilizers, processing conditions, and the compatibilizer to organoclay ratio on the morphology and mechanical, thermal and flow properties were investigated. Organoclay loading over 2 wt% prevented the intercalation mechanism and material properties, even in the presence of compatibilizer, as a consequence of large clay agglomerate formation. E-MA-GMA compatibilizer improved the intercalation ability of the polymer
however a substantial increase in mechanical properties was not obtained. PP-MAH is found to be a better compatibilizer. Processing conditions significantly affected both mechanical properties and morphology. When the processing temperature was decreased and screw speed was increased simultaneously, tensile and impact properties were improved owing to enhanced shear and dispersive forces. TEM analysis revealed that intercalated and delaminated structures were formed with the addition of PP-MAH compatibilizer. In addition to that, as the ratio of PP-MAH to organoclay was increased, more effective dispersion of organoclay was observed and hence resultant improvements in both tensile and impact properties were greater at compatibilizer to organoclay ratio of three. Cloisite®
15A exhibited the highest improvements in mechanical properties, although the degree of organoclay dispersion was better for Cloisite®
25A and particularly for Cloisite®
30B. Melt flow index values were lower compared to pure recycled polypropylene in the presence of organoclay and compatibilizers. DSC analysis indicated no significant change in the melting behavior of the matrix materials.
Yeniova, Canan Esma. "Impact Modified Polystyrene Based Nanocomposites." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610306/index.pdf.
Full text30B, 25A and 15A) were used as fillers. Nanocomposite preparation was performed in a co-rotating twin screw extruder. Initially elastomer and organoclay contents were kept at 5wt% and 1-2wt% respectively. Well dispersed silicate layers were obtained for the nanocomposite containing SEBS-g-MA and Cloisite®
25A owing to the high viscosity of SEBS-g-MA and the solubility of polystyrene end block of SEBS with PS matrix. Owing to higher hydrophobicity of Cloisite®
15A a better dispersion was expected compared to Cloisite®
25A, but, it was concluded that two long aliphatic tails of Cloisite®
15A limited the access of polymer chains to the clay surface. The desired impact strength values could not be achieved by using 5wt% elastomeric materials
therefore, it was decided to increase the SEBS-g-MA content up to 15, 20, 30 and 40wt%. With increasing elastomer content, increasing average elastomer domain size was obtained. Also, it was observed that with the addition of organoclay, the elastomeric domain size increases since the clay particles reside in the elastomer phase and at the interphase between elastomer and PS. The mechanical test results showed that the nanocomposites containing 15 and 20wt% SEBS-g-MA have the optimum average domain size that results in better impact strength values without deteriorating tensile properties.
Harris, Patrick James. "LAYERED POLYMERIC SYSTEMS:NEW PROCESSING METHODS AND NOVEL MECHANICAL DESIGN IN EXTENSIONAL RHEOLOGY." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1410544432.
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