Academic literature on the topic 'Biopolymer Film'

This work focuses on the fabrication of film based on natural biopolymers for wound healing application. Alginate and chitosan were choosen because of their oustanding properties such as biocompatible, hydrophilic and non-toxic. Earlier, the biopolymer film was fabricated by using alginate 1% wt and chitosan 1% wt. solutions at volume ratios of 99:1 and 97:3. Next, the biopolymer film solution was cross-linked with 1M CaCl2.2H2O for two hours and later dried for 24 hours at room temperature. Then, the surface properties of the prepared biopolymer films were characterised via Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscopy (AFM) and contact angle measurement. It was observed that the surface of the biopolymer film became rougher as the volume of the chitosan increases. This condition was confirmed with average surface roughness, RA for biopolymer film with ratio of 97:3 resulted in higher values. Also it was found that the surface of biopolymer films were hydrophilic after the contact angle was less than 90°. This can be concluded that the biopolymer based on alginate/chitosan is a promising candidate for wound healing materials particularly with good surface properties for faster healing process at the wound areas.

Hydrophilic behaviour of carrageenan macroalgae biopolymer, due to hydroxyl groups, has limited its applications, especially for packaging. In this study, macroalgae were reinforced with cellulose nanofibrils (CNFs) isolated from kenaf bast fibres. The macroalgae CNF film was after that treated with silane for hydrophobicity enhancement. The wettability and functional properties of unmodified macroalgae CNF films were compared with silane-modified macroalgae CNF films. Characterisation of the unmodified and modified biopolymers films was investigated. The atomic force microscope (AFM), SEM morphology, tensile properties, water contact angle, and thermal behaviour of the biofilms showed that the incorporation of Kenaf bast CNF remarkably increased the strength, moisture resistance, and thermal stability of the macroalgae biopolymer films. Moreover, the films’ modification using a silane coupling agent further enhanced the strength and thermal stability of the films apart from improved water-resistance of the biopolymer films compared to unmodified films. The morphology and AFM showed good interfacial interaction of the components of the biopolymer films. The modified biopolymer films exhibited significantly improved hydrophobic properties compared to the unmodified films due to the enhanced dispersion resulting from the silane treatment. The improved biopolymer films can potentially be utilised as packaging materials.

In this work, bionanocomposites based on two different types of biopolymers belonging to the MaterBi® family and containing two kinds of modified nanoclays were compounded in a twin-screw extruder and then subjected to a film blowing process, aiming at obtaining sustainable films potentially suitable for packaging applications. The preliminary characterization of the extruded bionanocomposites allowed establishing some correlations between the obtained morphology and the material rheological and mechanical behavior. More specifically, the morphological analysis showed that, regardless of the type of biopolymeric matrix, a homogeneous nanofiller dispersion was achieved; furthermore, the established biopolymer/nanofiller interactions caused a restrain of the dynamics of the biopolymer chains, thus inducing a significant modification of the material rheological response, which involves the appearance of an apparent yield stress and the amplification of the elastic feature of the viscoelastic behavior. Besides, the rheological characterization under non-isothermal elongational flow revealed a marginal effect of the embedded nanofillers on the biopolymers behavior, thus indicating their suitability for film blowing processing. Additionally, the processing behavior of the bionanocomposites was evaluated and compared to that of similar systems based on a low-density polyethylene matrix: this way, it was possible to identify the most suitable materials for film blowing operations. Finally, the assessment of the mechanical properties of the produced blown films documented the potential exploitation of the selected materials for packaging applications, also at an industrial level.

The research about of the biopolymers film from oil palm trunk starch had been done. Biopolymers film made by mixing of oil palm trunk starch (Elaeis guineensis Jacq.) and plasticizer sorbitol with the variation was 2:0,8 ; 2:1,0 ;2:1,2 (g/mL), then the film was molded on acrylic plate and dried in an oven at 40°C for 24 hours. The results of the film characterization show that the best variation of biopolymers on comparison 2:0,8 (g/mL) with the value of tensile strength was 4,26 MPa, percentage of elongation was 1,87 %, and film thickness was 0,16 mm, then it can be used as reference for addition 2 gram chitosan on the establishment of biopolymer film. It was characterized by tensile strength test with value was 14,00 MPa, pencentage of elongation with value was 3,20 %, and film thickness with value was 0,10 mm. The results of Differential Scanning Calorimetry (DSC) showed increasing of the endothermic temperature was 115,75 oC and exothermic temperature was 394,56 oC. The results of Thermal Gravimetry Analysis (TGA) showed that at a temperature of 340,1 0C the film to start decomposed. The value of % Swelling was 63,176%. The Fourier Transform Infra Red (FT-IR) result showed that in biopolymers film occurs physical interaction only. As well as, the antibacterial activity analysis showed that addition of chitosan on biopolymer film made Staphylococcus Aureus and Escherichia Coli bacterial was great inhibited with index antibacterial value of 0,625 respectively. From SEM analysis showed that film had been added by chitosan more homogenous than film without chitosan addition. The presence of chitosan addition tend to increase the physical and mechanical properties of biopolymer film.

Six microalgae strains were screened according to their biomass productivity and polymer synthesis, showing biomass productivity between 0.14 and 0.68 g/(L·d) for a 21-day growth period. Extracellular biopolymers from the spent culture media of Nostoc sp. (No), Synechocystis sp. (Sy), and Porphyridium purpureum (Pp) was obtained, and the yields of the clean biopolymer were 323, 204, and 83 mg/L, respectively. The crude biopolymer was cleaned up using a solid-phase extraction technique. The emulsification index E24 values for the clean biopolymer were 77.5%, 68.8%, and 73.3% at 0.323, 0.083, and 0.204 mg/mL, respectively. The clean biopolymer of the No strain showed the highest fungal growth inhibition against Fusarium verticillioides (70.2%) and Fusarium sp. (61.4%) at 2.24 mg/mL. In general, transparent and flexible biofilms were prepared using biopolymers of No and Pp. The microstructural analysis revealed the presence of pores and cracks in the biofilms, and the average roughness Ra values are 68.6 and 86.4 nm for No and Pp, respectively, and the root mean square roughness Rq values are 86.2 and 107.2 nm for No and Pp, respectively.

Natural biopolymers are an interesting resource for edible films production, as they are environmentally friendly packaging materials. The possibilities of the application of main animal proteins and natural polysaccharides are considered in the review, including the sources, structure, and limitations of usage. The main ways for overcoming the limitations caused by the physico-chemical properties of biopolymers are also discussed, including composites approaches, plasticizers, and the addition of crosslinking agents. Approaches for the production of biopolymer-based films and coatings are classified according to wet and dried processes and considered depending on biopolymer types. The methods for mechanical, physico-chemical, hydration, and uniformity estimation of edible films are reviewed.

The nondegradable nature and toxicity of organic liquid electrolytes reveal the design deficiency of lithium batteries in environmental protection. Biopolymers can be extracted from biomass under mild conditions, thus they are usually low cost and renewable. The unique characteristics of biopolymers such as water solubility, film-forming capability and adhesive property are of importance for lithium battery. The studies on the biopolymer materials for lithium batteries have been reviewed in this work. Although a lot of work on the biopolymer-based battery materials has been reported, it is still a challenge in the design of lithium battery with zero pollution and zero waste.

Chitosan is one of the most available biopolymers in nature, which is non-toxic, biocompatible and biodegradable. The crosslinked chitosan solution was synthesized by homogeneous reaction of medium molecular weight chitosan in aqueous acetic acid with glutaraldehyde as crosslinking agent. Then the solution was deposited on glass cover slip by spin coater to form a thin film. The functional group and chemical binding of crosslinked chitosan thin film has been confirmed by X-ray photoelectron spectroscopy (XPS). The chemical interaction between copper ion and the crosslinked chitosan thin film has also been analyzed by XPS. XPS revealed that copper ion adsorbed to the crosslinked chitosan thin film and the functional groups involved in the adsorption mechanisms of copper ion on the thin film were determined. This biopolymer thin film can be incorporated with surface plasmon resonance technique to produce a high potential optical sensor for detection of Cu (II) ion in solution.

The objective of this work is to study the effect of nanoclay fillers on the biodegradation and barrier properties of corn starch polymer-based biofilm. Starch derived from corn plant source was used to prepare a biofilm by plasticization method. The barrier properties, namely, water absorption, moisture permeation, oxygen permeation and swelling of unfilled and nanoclay-filled corn starch biofilms were examined. The results indicate: ∼22% reduced water absorption, 40% reduced moisture uptake, 30% reduced oxygen permeation and 31% reduced swelling for 2–3 wt.% nanoclay-filled biofilm, when compared with unfilled biopolymer. The biodegradation result of unfilled and nanoclay-filled film series indicates that the nanoclay addition delays the biodegradation and is a function of nanoclay content in the film. The tensile, dynamic mechanical analysis and biodegradable studies were conducted on the biopolymers before and after water absorption, and the result shows that the nanoclay-filled biopolymer increased these properties when compared with unfilled biopolymer even after water absorption and is dependent on the nanocomposite structure and morphology as examined by X-ray diffraction and transmission electron microscopy analysis.

Developing robust and biodegradable biopolymer films based on macroalgae is a challenging task because of its inadequate mechanical strength and poor moisture barrier attribute to its hydrophilic nature. A promising and sustainable approach to overcome this challenge is to reinforce the biopolymer film with polysaccharide microfibre (microcrystalline cellulose) derived from Gigantochloa levis bamboo (GL-MCC). Eucheuma cottonii macroalgae were used for the development of biopolymer films without further extraction and purification, which was considered economical and easy. The mechanical, water contact angle (WCA), water absorption capacity (WSC), and thermal behaviour of macroalgae-based biopolymer films revealed that the inclusions of GL-MCC significantly enhanced the durability, moisture barrier, and thermal stability of the biopolymer films. The enhancement is ascribed to the interaction between macroalgae and GL-MCC due to high compatibility. Moreover, the incorporation of GL-MCC successfully increased the rigidity of the macroalgae-based biopolymer films against microorganism and moisture attack, but remain biodegradable and environmental-friendly. The developed biodegradable macroalgae/GL-MCC biopolymer films can potentially be used as packaging materials.

In this study, a sustainable packaging system was developed to provide food safety and security. Soy protein isolate (SPI) was enzymatically modified by transglutaminase under different conditions to ensure desirable and optimized enzyme crosslinking activity before film preparation. Physicochemical properties including viscosity and molecular weight distribution of the modified proteins and films were measured. Results confirmed the enzymatic treatment is an effective way to modify the SPI based biopolymeric film. Modified films with the enzyme had significant increases in tensile strength (TS), percent elongation (%E), initial contact angle, and a reduction in swelling and protein solubility properties compared to the control films. FTIR and XRD spectra revealed that the enzyme treatment modified the structure of SPI film matrix. The optimal film preparation conditions achieved in this part were protein denaturation temperature 80 °C, and enzyme incubation time 2hr. We attempted to enhance antioxidant activity of enzymatically modified SPI film with the addition of two types of lignin, alkali lignin (AL) and lignosulphonate (LSS), at different concentrations. Results indicated that AL carried higher radical scavenging ability than LSS. Films containing AL showed high absorption in the UV region, and this UV-blocking ability increased with increasing lignin concentration. Deconvoluted FTIR spectra and XRD results suggested that the addition of lignin caused some changes in secondary structure of the protein matrix. The addition of lignin improved TS and thermal stability of films, but reduced %E as a function of lignin concentration. Radical scavenging activity and UV-blocking ability alongside improvement in physicochemical properties of enzymatic modified SPI film with lignin motivated us to apply this bioplastic in two types of oil, soy oil and fish oil. Results revealed that applying enzymatically modified SPI film with AL and LSS in the inner layer of a soy oil packaging system, decreased oxidation rate to around 75%, and pentanal production to about 40% of control. UV-blocking ability of AL caused reduction in oxidation rate for more than 75% compared with the normal packaging system. The effectiveness of this active packaging system in soy oil was greater than fish oil. Thus, the developed biopolymeric materials may have application to food packaging.
Ph. D.

O uso indiscriminado dos plásticos tem gerado graves problemas ambientais de acúmulo de material na natureza, poluição das águas, além de ser proveniente do petróleo, um recurso não renovável. Isso tem causado preocupação e, portanto, os cientistas e indústrias vêm buscando alternativas ao uso desses materiais, como por exemplo o emprego de materiais naturais e/ou biodegradáveis e o aproveitamento de subprodutos desperdiçados. O amido é um polímero natural que tem aspectos que o tornam promissor, como sua biodegradabilidade, baixo custo e disponibilidade. Para prolongar a vida útil dos alimentos, investigou-se o amido como matéria prima para a produção de filmes biodegradáveis e revestimentos comestíveis ativos. Além de atuar como barreira a gases e como proteção mecânica, as embalagens também podem carrear substâncias ativas como antioxidantes, antimicrobianos, entre outros. Foi estudado o efeito da incorporação de (0,3; 0,5 e 1,0) g de α-tocoferol/100 g de dispersão filmogênica nas propriedades morfológicas, mecânicas, ópticas, de superfície, de barreira ao vapor d\'água e à luz UV/Visível e antioxidantes dos filmes de amido de semente de jaca. A adição de α-tocoferol aumentou a resistência à tração e o módulo de elasticidade nos filmes com até 0,5% de α-tocoferol. Também aumentou a barreira ao vapor d\'água, possivelmente devido à natureza hidrofóbica do α-tocoferol e ao efeito de tortuosidade causado por ele na matriz polimérica, embora a solubilidade em água não tenha diferido significativamente entre os filmes. O α-tocoferol proporcionou aumento na barreira contra a luz UV, especialmente nos comprimentos de onda entre (200 e 310) nm. A opacidade e o parâmetro de cor b* aumentaram significativamente, o que significa que a incorporação de α-tocoferol tornou os filmes mais opacos e amarelados. A hidrofobicidade da superfície aumentou significativamente (p < 0,05) com adição de α-tocoferol, principalmente no filme com 0,5% de α-tocoferol. A capacidade antioxidante aumentou significativamente com adição de até 0,5% de α-tocoferol. O filme controle (sem α-tocoferol) não apresentou capacidade antioxidante. Concluiu-se que o material de amido de semente de jaca incorporado de α-tocoferol tem potencial para ser usado como revestimento ativo para alimentos com alto teor de gordura. Entre as formulações produzidas, a de 0,5% de α-tocoferol foi a melhor, porque apresentou atividade antioxidante tão boa quanto o filme 1,0% de α-tocoferol e propriedades mais interessantes, como a microestrutural, mecânica, óptica e de superfície.
Indiscriminate use of plastics has been generating environmental problems, like accumulation of materials, water pollution, as well as depleting a non-renewable resource (crude oil). This has been causing concern, therefore scientists and industries are seeking alternatives for these materials, for example, the employment of natural and/or biodegradable materials and the reuse of wasted byproducts. Starch is a natural polymer with many promising aspects, like its biodegradability, low cost and availability. Aiming at prolonging shelf-life of food products, starch has been investigated as a feedstock for development of edible active films and coatings. Besides acting as a barrier against gases and as mechanical protection, packages also may carry active substances (antioxidants, antimicrobials, etc.). The effects of the incorporation of (0.3; 0.5 and 1.0) g α-tocopherol/100 g filmogenic dispersion on the morphological, mechanical, optical, surface, water vapor permeability, barrier to UV/Visible light and antioxidant properties of jackfruit seed starch films were studied. Addition of α-tocopherol increased the tensile strength and the elastic modulus up to 0.5%. It also increased the water vapor barrier, possibly due to α-tocopherol\'s hydrophobic nature and because it caused a tortuosity effect in the polymer matrix, although the film solubility was not significantly affected. α-tocopherol improved the UV light barrier, especially in the wavelengths between (200 and 310) nm. The opacity and the color parameter b* increased significantly, which means that films with α-tocopherol became more opaque and yellowish. Surface hydrophobicity increased with the incorporation of α-tocopherol, especially for the 0.5% α-tocopherol film. The antioxidant activity increased significantly up to 0.5% α-tocopherol. The film without α-tocopherol presented no antioxidant capacity. Therefore, jackfruit seed starch films incorporated with α-tocopherol have potential to be used as edible active coatings for high fat content foods. Between the formulations produced, the one with 0.5% of α-tocopherol was the best, because it presented an antioxidant activity similar to the film with 1.0% of α-tocopherol and superior characteristics, like microstructural, mechanical, optical and surface properties.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior
Hydrocolloid and lipid-based films although they are considered technological innovations, have been studied since the mid-90s as potential replacements for synthetic polymers. This study aimed to develop composite films monolayer (Ms) and bilayers (Bs), with incorporation of acetic acid ester of monoglyceride (MGA) in different concentrations and rosemary essential oil peppermint, Lippia sidoides, for applicability in foods with high moisture content. In a previous experiment, it was determined the percentage of 40% (w/w) of plasticizer (D (-) sorbitol) for composite film formation (starch + lipid). Based on this film, it was prepared an experimental design, using plasticizer and various concentrations of AMS (0 to 20% w/w). The films were developed through casting with a thickness of 0.8 mm and dried at room temperature (25 ÂC Â 1 ÂC) 12-15 hours. Diffusion tests were performed on agar; physical properties (color, opacity, thickness, moisture and solubility); morphological (medium size, polydispersity â PdI â zeta potential, scanning electron microscopy - SEM, infrared spectroscopy and Fourier transform - IS-FT); barrier (permeability to water vapor - PWV); mechanical tests (tensile strength - TS, rupture elongation - RE - and elastic modulus - EM); termoanalÃtica (differential scanning calorimetry - DSC). Itâs believed that the films have shown a bacteriostatic studied in microorganisms (S. aureus, L. monocytogenes, E. coli, P. aeruginosa and S. Typhimurium). Color analysis showed statistical significance (p<0.05) between mono and bilayer films. The opacity, showed variations from 214.74 to 323.12 A.nm (Ms) and 161.69 to 411.54 A.nm (Bs), except for the treatments with 10% and 15% lipid that doesnât varied statistically (p<0.05) between Ms and Bs. The thicknesses resulted in asignificant difference (p<0.05) between treatments, ranging from 12% (Ms) and 48% (Bs). The films showed low solubility in aqueous media, with no separation of the layers. The Bs films presented stability of filmogenic solutions, combined with electrokinetic interactions of interaction between the layers, low solubility (16%), heat resistance, PdIbetween0.35 to 0.53; PVA around 2.232 g.mm/kPa.h.mÂ, whose mechanical tests demonstrated tha the Bs films are hard and low elasticity with respect to Ms films, development perspective of a non-flexible packaging with excellent application in food with high moisture content, animal and/or plant origin.
Os filmes à base de hidrocÃloides e lipÃdios apesar de serem consideradas inovaÃÃes tecnolÃgicas, vÃm sendo estudados desde meados dos anos 90 como substitutos em potencial dos polÃmeros sintÃticos. Este trabalho objetivou desenvolver filmes compostos em monocamada (Ms) e bicamadas (Bs), com incorporaÃÃo de Ãster de monoglicerÃdeo de Ãcido acÃtico (MGA) em diferentes concentraÃÃes e, Ãleo essencial de alecrim-pimenta, Lippia sidoides, para aplicabilidade em alimentos com alto teor de umidade. Em experimento prÃvio, determinou-se o percentual de 40% (m/m) de plastificante (D (-) sorbitol) para formaÃÃo de filme composto (amido+lipÃdio). Com base neste filme, elaborou-se um delineamento experimental, utilizando-se plastificante e, diferentes concentraÃÃes de MGA (0 a 20%, m/m). Os filmes foram desenvolvidos atravÃs de casting, com espessura de 0,8 mm e secos à temperatura ambiente (25 ÂC  1 ÂC) entre 12-15 horas. Foram realizados teste de difusÃo em Ãgar; propriedade fÃsica (cor, opacidade, espessura, umidade e solubilidade); morfolÃgica (tamanho mÃdio, polidispersividade â PDI, potencial zeta, microscopia eletrÃnica de varredura â MEV, e espectroscopia no infravermelho com transformada de Fourier â FT-IR); barreira (permeabilidade ao vapor de Ãgua â PVA); ensaios mecÃnicos (resistÃncia à traÃÃo â RT, elongaÃÃo de ruptura â ER â e mÃdulo de elÃstico â ME); termoanalÃtica (calorimetria diferencial de varredura â DSC). Acredita-se que os filmes tenham apresentado aÃÃo bacteriostÃtica nos micro-organismos estudados (S. aureus, L. monocytogenes, E. coli, P. aeruginosa e S. Typhimurium). A cor apresentou diferenÃa estatÃstica (p<0,05) entre os filmes mono e bicamadas. A opacidade, apresentou variaÃÃes de 214,74 a323,12 A.nm (Ms) e, 161,69 a411,54 A.nm (Bs), exceto para os tratamentos com 10% e 15% de lipÃdio que nÃo variaram estatisticamente (p<0,05) entre Ms e Bs. A espessura resultou em uma diferenÃa significativa (p<0,05) entre os tratamentos, variando 12% (Ms) e 48% (Bs). Os filmes apresentaram baixa solubilidade em meio aquoso, sem que houvesse a separaÃÃo das camadas. Os filmes Bs apresentaram estabilidade das soluÃÃes filmogÃnicas, associado a interaÃÃes eletrocinÃticas de interaÃÃo entre as camadas, baixa solubilidade (16%), resistÃncia tÃrmica, PDI entre 0,35-0,53; PVA em torno de 2,232 g.mm/kPa.h.mÂ, cujos ensaios mecÃnicos demonstraram que os filmes Bs sÃo rÃgidos e com baixa elasticidade em relaÃÃo aos filmes Ms, evidenciando perspectiva de desenvolvimento de uma embalagem nÃo flexÃvel, com potencial de aplicaÃÃo em alimentos com alto teor de umidade.

Актуальною проблемою є пошук універсального, комфортного засобу на основі природних біополімерів для використання в повсякденному житті та для лікувальних аплікацій в косметологічній практиці. В даній роботі були створені плівки наступного складу: Alg-Gel, Alg-Ch-Gly, Alg-Gel-Ch-Gly.

Hard gelatin capsules have been used for drug delivery for a long time. The current production process takes advantage of the very unusual properties of gelatin: gelation, very low viscosity, film mechanical properties and film solubility. Although the hard gelatin capsules present many advantages compared to other drug delivery systems, their uses are restricted because of the animal origin of the gelatin. A HPMC gelling agent system is currently used for producing animal product free hard capsules. This work examines the possibility of using a different system in a similar production process. The gelling conditions of the mixed system, the potential of various film formers and the mechanical properties of some films are considered. Gelling agent filler mixed systems were prepared, and the limit concentration of filler that allowed gelation was noted. It was shown that none of the gelling agents would always gel and gelation was never prevented by the maltodextrin (up to a concentration of 14%). The gelation inhibition obtained is likely to be due to phase separation. The charge densities of the various products were also measured. It showed that when there is little charge density difference, gelation is inhibited. Polymer compatibility is increased by increasing the charge density differences. However, an asymmetry is observed. This is explained by the necessary shift of the binodal that would predict prevention of incompatibility. Many films were cast from various biopolymers. The films were screened via sensory analysis. The process allowed to define terms that discriminate the films. The results showed that cellulose derivatives, alginate and alginate derivative films had sensory analysis scores similar to gelatin. Although none of the starch derivatives had such good scores, some presented some promising results. Alginate and caseinate films were selected for further analysis. The mechanical properties of gelatin and HPMC films were compared by puncture tests. The results at a relative humidity of 44% are similar. However, the effect of the moisture content on both films' mechanical properties showed differences. The fracture patterns and polarised microscopy observation were also very different. Alginate films' mechanical properties were similar to gelatin. However, alginate films are not soluble in acidic environments. The effects of molecular weight on the mechanical properties of cellulose derivatives and alginates films were different. Increasing the calcium content of the alginate sample gave similar results to those obtained by increasing the molecular weight. It is proposed that ultimate deformation occurs through different processes in various films. Alginate/gelatin films are thought to deform through crazing, and the fracture process generates many surfaces (lines). Molecular weight and crosslinking would stabilise the crazes. On the other hand, cellulose derivative would deform through slippage and the energy is dissipated during deformation. This is consistent with the orientation observed after fracture, the lack of new surfaces and the high hydrophobicity of these polymers. Caseinate films of sodium, potassium, calcium and magnesium were studied. Sodium caseinate presented the best mechanical properties. Glycerol proved to be the best plasticiser. Glyoxal crosslinking or increase in pH did not improve the mechanical properties of these films. Caseinate films are poorer than alginate, HPMC or gelatin films. Caseinate deformation processes might occur through both slippage and crazing owing to the low molecular weight and high hydrogen bonding ability. Overall, different deformation processes can lead to similar mechanical behaviour. None of the films studied is likely to replace gelatin or HPMC. More complex systems are proposed for further study.

The main objective of the work presented in this thesis was to study the behaviour of biopolymer films with respect to their mechanical and physicochemical properties and to test hypotheses as to their molecular origins. The thesis describes four studies. In the first study the granule, paste and film properties of common starches from six different botanical sources; i.e. cassava, corn, pea, potato, rice and wheat; were characterised with the aim of identifying the main factors which affect the properties of the starch films.

Abstract Biodegradable starch-glycerol based films were obtained. The influence of lipid compounds (palmitic, stearic and oleic acid), other polymers (hydroxypropylmethylcellulose and sodium caseinate) and bioactive compounds (¿-tocoferol, D-limonene and orange essential oil) on film properties (oxygen and water vapour barrier, optical, mechanical, nano- and microstructural). Furthermore the effect of storage time on films¿ properties was also considered. Fatty acids addition did not improve the water vapour ability of films except for non-stored saturated fatty acids containing films. X-ray diffraction results showed that cristallinity of films increased with storage time, thus increasing the stiffness and decreasing the gloss of films. Furthermore, crystallinity affected the water sorption capacity of films as function of relative humidity and temperature. Glass transition temperature of starch films varied with saturated fatty acids addition. However, oleic acid did not affect this parameter. The presence of fatty acids promoted the formation of V-type structures, thus indicatin the formation of amylose-lipid complexes that inhibited the developmet of other crystalline structures. The effect of the incorporation of other biopolymers to improve the functionality of starch films was also studied. Hydroxypropylmethylcellulose (HPMC) addition inhibited starch retrogradation. However, obtained films were more permeable, specially in case of oxygen. HPMC addition produced phase separation as it was observed by scanning electron microscopy. On the contrary, sodium caseinate incorporation (NaCas) allowed to obtain homogeneous films and less permeable to oxygen. Obtained films showed less mechanical resistance in comparison with pure starch films but a greater flexibility without increasing the water vapour permeability. Rearrangement of polymers chains during storage reduced the mechanical resistance, the extensibility and the gloss of composite films. Regarding the obtained results, the film including a starch:protein ratio of 50:50 was choosen as the film with the most adequate properties. Composite film (starch:Nacas ratio = 50:50) was studied as a matrix for the incorporation o active compounds (¿-tocopherol, D-limonene and orange essential oil). The effect of ¿-tocopherol addition was compared with the incorporation of oleic acid and their mixture. Lipids addition promoted phase separation between starch and NaCas due to the different interactions between each polymer and the lipids. Furthermore, oleic acid addition increased significantly the oxygen permeability whereas ¿-tocopherol greatly improved the antioxidant capacity of films without affecting the oxygen permeability. D-limonene and orange essential oil incorporation was carried out by forming rapeseed and soy nanoliposomes, which acted as carriers of bioactive components. Nanoliposomes incorporation was performed directly in starch-NaCas dispersions without any homogenization, to avoid nanoliposomes damages. Bioactive compounds addition did not confer antimicrobial capacity to the films (except for soy-orange oil nanoliposomes containing film) probably due to the high stability of nanoliposomes and the low antibacterial activity of D-limonene and orange essential oil.
Se han desarrollado y caracterizado films biodegradables a base de almidón de maíz y glicerol como plastificante, evaluando al mismo tiempo el efecto de la adición de componentes lipídicos (ácido palmítico, esteárico y oleico), otros polímeros (hidroxipropilmetilcelulosa y caseinato de sodio) y compuestos bioactivos (¿-tocoferol, aceite esencial de naranja y D-limoneno) sobre las propiedades de los films (propiedades barrera al vapor de agua y al oxígeno, ópticas, mecánicas, micro y nanoestructurales). Asimismo se evaluó la influencia del tiempo de almacenamiento en las propiedades de los films. La adición de ácidos grasos no mejoró notablemente la permeabilidad al vapor de agua excepto en el caso de los films con ácidos grasos saturados y solo en films no almacenados. Los resultados de difracción de rayos X mostraron que la cristalinidad aumentó con el tiempo de almacenamiento, incrementándose la rigidez, y disminuyendo el brillo de los films. Del mismo modo, la cristalinidad afectó a la capacidad de sorción de agua de los films en función de la humedad relativa y la temperatura. La temperatura de transición vítrea de los films de almidón se vio afectada por la adición de ácidos grasos saturados pero no por la adición de ácido oleico. La presencia de dichos componentes promovió la formación de estructuras cristalinas tipo V, indicando la formación de complejos entre los lípidos y las cadenas de amilosa e inhibiendo la formación de otros tipos de formas cristalinas. Se analizó también el efecto de la incorporación de otros biopolímeros en la posible mejora de la funcionalidad de los films de almidón. En las mezclas con hidroxipropilmetilcelulosa (HPMC), se inhibió la retrogradación del almidón en los films composite, pero se observó un efecto negativo en las propiedades barrera de los mismos, que fueron más permeables, principalmente al oxígeno. La adición de HPMC produjo separación de fases en los films (observada por microscopía electrónica de barrido). Por el contrario, la incorporación de caseinato de sodio (NaCas) permitió formar films homogéneos y menos permeables al oxígeno. Los films presentaron una resistencia mecánica algo menor que los films de almidón puro pero una mayor flexibilidad sin incrementar los valores de permeabilidad al vapor de agua. La reorganización de las cadenas de los polímeros con el tiempo de almacenamiento provocó la disminución de la resistencia mecánica, la deformabilidad y el brillo de los films composite. Atendiendo a los efectos observados, se eligió como formulación más adecuada el film composite formado por almidón y NaCas con un ratio de polímeros del 50:50. El film composite de almidón y NaCas (50:50) se estudió como matriz para la incorporación de compuestos bioactivos como son el ¿-tocoferol y el aceite esencial de naranja o su principal componente, el D-limoneno. El efecto de la adición de ¿-tocoferol se comparó con la influencia de la adición de ácido oleico y también con la adición de ambos compuestos. La adición de lípidos provocó una separación de fases entre el almidón y el NaCas debido a la diferente interacción entre cada polímero y los lípidos. Asimismo la adición de ácido oleico incrementó significativamente la permeabilidad al oxígeno, al contrario que el ¿-tocoferol, que además impartió a los films una elevada capacidad antioxidante. La incorporación de aceite esencial de naranja y D-limoneno se realizó utilizando nanoliposomas de lecitina de soja y lecitina de colza que encapsularon los compuestos activos. La incorporación de nanoliposomas en los films se realizó directamente en las dispersiones acuosas sin posterior homogeneización para evitar su ruptura. La adición de los compuestos bioactivos en forma de nanoliposomas no confirió capacidad antimicrobiana a los films, salvo en el caso de los nanoliposomas de lecitina de soja con aceite esencial, debido probablemente a la dificultad de los compuestos encapsulados para difundir en el film por la gran estabilidad de los liposomas y a la baja actividad antilisteria del D-limoneno y el aceite esencial de naranja.
Jiménez Marco, A. (2013). Propiedades de films de almidón de maíz. Influencia de la incorporación de lípidos, biopolímeros y compuestos bioactivos [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/28214
TESIS
Premiado

This thesis addresses both the theory and simulation of diffusion of moisture in water-based biopolymer films, whose preliminary use is as adhesives on glass bottles in the labelling industry. The first part explores the kinetics of dehydration of thin films of these biopolymer materials. The second part of the thesis deals with moisture intake into both dried thin films and into the wet biopolymer gel network. Mathematical simulations based on Fick's laws of diffusion have been developed as a tool to understand the underpinning mechanisms of diffusion and of evaporation to discover which, if either plays a more dominant role in controlling the dehydration process. By inputting a series of different initial and final moisture contents, a full spectra of scenarios has been examined to aid understanding of the dehydration process. Numerical calculations where diffusion is the controlling mechanism as well as simulations where evaporation controls the process have been considered and discussed. Models in which a combination of both diffusion and evaporation are equally important are also studied. Fixed and moving boundary conditions are applied to the models and compared with dehydration results obtained experimentally. A simple method has been developed to assess the rehydration process of a dried biopolymer film and similar simulations have also been constructed to describe the rehydration of a water droplet into the thin, dried films. A novel method to investigate the migration of water into casein biopolymer gels using acoustic techniques has been developed and validated. The preliminary results are promising, highlighting the potential capability of the method. As the composition of a material changes, the speed of a wave of sound being passed through the material changes, so by monitoring this change as a function of time, concentration profiles of the biopolymer material can be constructed. Simulated concentration profiles were successfully produced based on Fick's second law of diffusion, to obtain a diffusion coefficient dependent on both time and position. By fitting these curves to the experimental data, diffusion coefficients are obtained with values of the same order of magnitude as those calculated from the experiments on a dehydrating thin film of the same composition.

Les plastiques sont aujourd'hui des matériaux ubiquitaires utilisés dans tous les aspects de notre vie quotidienne, en particulier pour l'emballage alimentaire. Cependant, après usage, les plastiques sont une source de pollution de notre environnement naturel. Certains plastiques biodégradables et biosourcés sont déjà disponibles sur le marché, comme l’acide polylactique (PLA), mais ils présentent des performances inférieures. Ce travail de thèse vise à: 1) étudier la stabilité des films de PLA dans diverses conditions de température, d'humidité relative, de pH, d'exposition à des liquides ou à des vapeurs... 2) mieux comprendre l'impact de certains procédés industriels tels que les traitements corona ou pressage à chaud sur le PLA 3) combiner le PLA à des couches de gluten de blé afin de produire des complexes ayant des propriétés barrière plus élevées.Les films de PLA ont été produits par la société Taghleef Industries sur demande et avec des traitements de surface spécifiques, comme le traitement Corona. Des films et des enductions à basede gluten de blé ont été développés à l’échelle laboratoire ainsi que des complexes tricouches PLA- gluten-PLA. Les propriétés physiques et chimiques des films ont été étudiées par différentes techniques issues des sciences des matériaux et des aliments ont été utilisées, telles que l’analyse enthalpique différentielle (DSC), l'analyse thermogravimétrique (TGA), la chromatographie d'exclusion de taille (SEC), la microscopie de force atomique (AFM), la microscopie électronique (SEM), la spectroscopie infrarouge à transformée de Fourier (ATR-FTIR) et la spectroscopie de rayons X (XPS). Les propriétés fonctionnelles telles que la perméabilité à la vapeur d'eau, à l'oxygène (O2), au dioxyde de carbone (CO2) ou à l'hélium (He), la sorption de gaz et de vapeurs, les propriétés mécaniques et de surface ont également été étudiées.Exposés au CO2, les films de PLA présentent une isotherme de sorption linéaire avec l’augmentation de pression. Cependant les modifications physiques et chimiques induites à des pressions élevées n'affectent pas son utilisation dans le domaine d’application alimentaire. Au contraire, lorsque les films de PLA sont exposés à l'humidité à l'état liquide ou vapeur, leur dégradation survient après deux mois à 50 ° C (essai accéléré) suite à son hydrolyse. Cette détérioration chimique, mise en évidence par une diminution significative de la masse molaire, entraine une perte de transparence, mais également par une augmentation de la cristallinité. Par ailleurs, le pH n'affecte pas le taux d'hydrolyse, ce qui est d'un intérêt essentiel pour conditionner des aliments humides.Les films à base gluten de blé ont été choisis pour leurs propriétés de barrière élevées lorsque l’humidité relative reste faible. L'incorporation de lipides n'a pas apporté d'amélioration de leurs performances barrières. Cependant, l'utilisation d’un procédé d’homogénéisation à haute pression a permis une meilleure dispersion du gluten, ce qui a conduit à des films plus homogènes ayant ainsi de meilleures propriétés fonctionnelles. Ces conditions ont donc été retenues pour réaliser des complexes à 3 couches par assemblage d'une couche de gluten de blé entre deux couches de PLA en utilisant un pressage à chaud (10 MPa, 130 ° C, 10 min).La technologie de pressage à chaud montre une forte influence sur les films de PLA, de gluten et sur les tricouches. Elle induit une cristallisation accrue du PLA, ce qui augmente ses propriétés de barrière d'environ 40% et 60%, respectivement pour l'eau et l'oxygène. Cela masque par contre l’effet du traitement corona. D’autre part, le pressage à chaud induit une restructuration du réseau de gluten qui améliore les propriétés de barrière aux gaz des complexes, mais provoque aussi une évaporation de l'eau à l'interface gluten / PLA défavorable à l’adhésion des couches (...)
Poly(lactic acid) (PLA) is a biodegradable and renewable polyester, which is considered as the most promising eco-friendly substitute of conventional plastics. It is mainly used for food packaging applications, but some drawbacks still reduce its applications. On the one hand, its low barrier performance to gases (e.g. O2 and CO2) limits its use for applications requiring low gas transfer, such as modified atmosphere packaging (MAP) or for carbonate beverage packaging. On the other hand, its natural water sensitivity, which contributes to its biodegradation, limits its use for high moisture foods with long shelf life.Other biopolymers such as wheat gluten (WG) can be considered as interesting materials able to increase the PLA performances. WG is much more water sensitive, but it displays better gas barrier properties in dry surroundings. This complementarity in barrier performances drove us to study the development of multilayer complexes PLA-WG-PLA and to open unexplored application scenarios for these biopolymers.This project was thus intended to better understand how food components and use conditions could affect the performances of PLA films, and how these performances could be optimized by additional processing such as surface modifications (e.g. corona treatment and coatings).To that aim, three objectives were targeted:- To study the stability of industrially scale produced PLA films in contact with different molecules (CO2 and water) and in contact with vapour or liquid phases, with different pH, in order to mimic a wide range of food packaging applications.- To better understand the impact of some industrial processes such as corona or hot press treatments on PLA.- To combine PLA with WG layer to produce high barrier and biodegradable complexes.Different approaches coming from food engineering and material engineering were adopted. PLA films were produced at industrial scale by Taghleef Industries with specific surface treatments like corona. Wheat gluten films, coatings and layers were developed and optimized at lab scale as well as the 3-layers PLA-WG-PLA complexes. Different technologies able to mimic industrial processes were considered such as hot press, high pressure homogenization, ultrasounds, wet casting and spin coating. The physical and chemical properties of PLA films were then studied at the bulk and surface levels, from macroscopic to nanometer scale. The functional properties like permeability to gases (e.g. O2 and CO2) and water, gas and vapour sorption, mechanical and surface properties were also investigated.Exposed to CO2, PLA films exhibited a linear sorption behaviour with pressure, but the physical modifications induced by high pressure did not affect its use for food packaging. However, when exposed to moisture in both liquid and vapour state (i.e. environments from 50 to 100 % relative humidity (RH)), PLA was significantly degraded after two months at 50 °C (accelerated test) due to hydrolysis. This chemical deterioration was evidenced by a significant decrease of the molecular weight, which consequently induced a loss of transparency and an increase of the crystallinity. The hydrolysis was accelerated when the chemical potential of water was increased, and it was surprisingly higher for vapour compared to liquid state. In addition, pH did not affect the rate of hydrolysis.Knowing much better the limitation of PLA films, the challenge was to improve its functional properties by combining them with WG, as a high gas barrier bio-sourced and biodegradable polymer. The use of high pressure homogenization produced homogeneous WG coatings, with improved performances. This process was thus selected for making 3 layer complexes by assembly of a wheat gluten layer between two layers of PLA, together with corona treatment and hot press technologies.Corona treatment applied to PLA physically and chemically modified its surface at the nanometer scale (...)
I materiali plastici convenzionali trovano impiego in tutti campi della nostra vita, specialmente nel settore del packaging alimentare, ed in seguito all’utilizzo contaminano e danneggiano il nostro ecosistema. Materiali plastici derivanti da risorse naturali e biodegradabili, come acido polilattico (PLA), sono attualmente disponibili sul mercato anche se caratterizzati da performances inferiori.Questo progetto di dottorato è mirato 1) allo studio della stabilità di film di PLA a varie condizioni di stoccaggio come temperatura, umidità relativa, pH, o esposizione a vapori o gas; 2) a comprendere meglio le influenze di alcuni processi industriali come trattamento corona e hot press nelle proprietà dei film di PLA; 3) a sviluppare complessi multistrato tra film di PLA e di glutine che abbiano proprietà barriera più elevate rispetto ai singoli film.Gli imballaggi a base di PLA sono stati prodotti da Taghleef Industries, produttore leader nel settore e dotato di infrastrutture atte ai trattamenti di modificazione di superfice come il trattamento corona. I film a base di glutine e i coatings sono stati sviluppati e ottimizzati su scala di laboratorio, così come i complessi trilaminari PLA-glutine-PLA.Le proprietà fisiche e chimiche dei film di PLA sono state investigate a livello di superficie, così come a livello di bulk. Diverse tecniche analitiche, provenienti dal campo delle scienze dei materiali e delle scienze degli alimenti, sono state adottate in questo progetto di dottorato come calorimetria differenziale a scansione (DSC), termogravimetria (TGA), cromatografia di esclusione molecolare (SEC), microscopia a forza atomica (AFM), microscopia elettronica a scansione (SEM), spettrofotometria infrarossa a trasformata di Fourier in riflettanza totale attenuata (ATR-FTIR) e spettroscopia fotoelettronica a raggi X (XPS).Le proprietà funzionali come le permeabilità al vapore acqueo (H2O), all’ossigeno (O2), al diossido di carbonio (CO2) o all’elio (He) sono state investigate, cosi come l’assorbimento di gas e/o vapori, le proprietà meccaniche e le proprietà di superfice.Nonostante i film di PLA assorbano linearmente CO2 a pressioni crescenti, l’assorbimento di tale gas è ridotto a basse pressioni in modo da non modificare le sue proprietà fisiche – come contrariamente osservato quando il PLA è esposto a CO2 ad alte pressioni – e da non influenzare negativamente il suo utilizzo come imballaggio alimentare. Ad ogni modo, quando i film di PLA sono esposti ad ambienti umidi, o quando sono immersi in acqua liquida, sono significativamente degradati per idrolisi dopo due mesi di stoccaggio a 50 °C (test accelerato). Questo deterioramento chimico è stato evidenziato da una significativa riduzione del peso molecolare del PLA che, conseguentemente, induce una sua perdita di trasparenza e ne incrementa la sua cristallinità. Inoltre, è stato evidenziato che il pH non influenza la velocità di idrolisi. Quest’informazione ha importanza pratica per possibili utilizzi di PLA come imballaggio di alimenti ad alta umidità.Il glutine è stato scelto per le sue alte proprietà barriera, quando è protetto da ambienti ad alta umidità. Si è visto che l’incorporazione di lipidi non porta con sé grandi miglioramenti nelle performances dei film a base di glutine. Invece, l’utilizzo della tecnologia di omogeneizzazione ad alte pressioni permette una migliore dispersione del glutine, ottenendo film più omogenei e con migliori proprietà funzionali. Questa tecnologia è stata quindi scelta per produrre i complessi multistrato, intercalando i film di glutine tra due film di PLA, usando il trattamento hot press (10 MPa, 130 °C, 10 min). Si è osservato che il trattamento hot press modifica le proprietà dei film di PLA, di glutine e dei film multistrato Hot press induce cristallizzazione in PLA, e conseguentemente aumenta le sue proprietà barriera complessive, approssimativamente al 40 % all’acqua e al 60 % all’ossigeno (...)
Los materiales plásticos tradicionales son utilizados en todos los campos de nuestra vida y en particular modo como embajales de productos alimenticios; los cuales después de ser utilizados contaminan y dañan nuesto medio ambiente. Materiales plásticos derivados de recursos naturales y biodegradables, como el ácido poliláctico (PLA) se encuentran actualmente disponibles en el mercado a pesar de sus menores performances. Este proyecto de doctorado está orientado 1) al estudio de la estabilidad de películas de PLA bajo diferentes condiciones como temperatura, humedad relativa, pH o exposición a vapores o gases, 2) comprender los efectos en las propiedades de las películas de PLA de algunos procesos industriales como el tratamiento corona y hot press, 3) desarrollar complejos multicapas de PLA y gluten que tengan propiedades barrera mejores que las de las películas individuales.Los embalajes a base de PLA han sido producidos por Taghleef Industries, productor líder en el sector y dotado de las infraestructuras industriales adaptadas a los tratamientos superficiales como el tratamiento corona. Las películas de gluten y los coatings han sido desarrollados a escala de laboratorio, así como los complejos tricapa PLA-gluten-PLA.Las propiedades físicas y químicas de las películas de PLA han sido investigadas a nivel de superficie así como a nivel de bulk. Diferentes técnicas de análisis, frecuentemente utilizadas en los campos de las ciencias de los materiales y de las ciencias de los alimentos, han sido empleadas en este proyecto como calorimetría diferencial de barrido (DSC), análisis termogravimétrico (TGA), cromotagrafía de exclusión por tamaño (SEC), microscopía de fuerza atómica (AFM), microscopía electrónica de barrido (SEM), espectroscopía de infrarrojos por transformada de Fourier con reflectancia total atenuada (ATR-FTIR) y espectroscopía fotoelectrónica de rayos X (XPS).Las propiedades funcionales de los embalajes como las permeabilidades al vapor de agua, al oxígeno (O2), al dióxido de carbono (CO2) o al helio (He) han sido investigadas, asi como la absorción de gases/vapores, las propiedades mecánicas y las propiedades superficiales. A pesar de que las películas de PLA absorven linealmente CO2 a presiones mayores, la absorción del gas es reducida a bajas presiones y no modifica las propiedades físicas del PLA, como contrariamente sucede cuando el PLA es expuesto a altas presiones de CO2. Por lo tanto, su influencia en las propiedades funcionales del PLA es mínima en las normales aplicaciones alimentarias. De todos modos cuando los embalajes de PLA son expuestos a ambientes húmedos o cuando son sumergidos en agua, procesos de hidrólisis los degradan significativamente después de dos meses de conservación a 50 °C (test acelerado). Este deterioramiento químico ha sido evidenciado por una significativa reducción del peso molecular del PLA, que en consecuencia induce una pérdida de transparencia y un aumento de su cristalinidad. Además, se ha observado que el pH no influye en la velocidad de hidrólisis. Esta información tiene una importancia práctica para posibles usos del PLA como embalajes de alimentos a alta humedad. El gluten ha sido elegido por sus altas propiedades barrera cuando es protegido de ambientes a alta humedad. La incorporación de lípidos en las películas de gluten no han mejorado sus performances. Pero la tecnología de la homogenización a altas presiones ha permitido mejorar la dispersión del gluten, obteniendo películas más homogéneas y con mejores propiedades funcionales. Esta tecnología ha sido, por lo tanto, elegida para producir los complejos multicapa, intercalando las películas de gluten entre dos de PLA, utilizando el tratamiendo hot press (10 MPa, 130 °C, 10 min) (...)

This research work aimed to evaluate the physicochemical properties of arrowroot starch films plasticized with glycerol and incorporated in film-forming solution directly (D) and by sprinkling (S) with 0%, 20%, 30%, 40% (mass blackberry solids / biopolymer mass) of blackberry pulp (BL) powder and freeze dried microencapsulated blackberry pulp (ML) using mixture of gum arabic and arrowroot starch (1: 1, mass / mass). Thickness, water solubility and water vapour permeability of the films significantly increased with increasing concentration of blackberry powder. Compared to arrowroot starch film (0%), the surface of films with BL and ML powder became irregular and rough. Keywords: Lyophilization; microstructure; water solubility; water vapor permeability; packing.

The objective of this research is to prepare a hybrid biopolymer blend using PLA and PHBV with enhanced mechanical and thermal properties. Bio-based PLA and PHBV blends were prepared using the melt-mixing procedure. Tensile, FTIR, DSC, TGA, optical microscopy (OM), and scanning electron microscopy (SEM) tests were performed to investigate mechanical properties, bonding interaction, glass transition temperature, melting and crystalline enthalpy, thermal decomposition, and morphological analysis. Different percent (1, 2, and 3 wt%) of nanoclay was added to the system to observe the bonding interaction. It was observed that the crystallinity increases with increasing amount of nanoclay. The result showed that the tensile strength of PLA thin film and PHBV film was found to be 31.1 MPa and 14.41 MPa, respectively. Hence, PLA has better mechanical property than PHBV. On the other hand, thermal property of PHBV thin film was found to be better than that of PLA. To optimize both mechanical and thermal properties of PLA and PHBV hybrid biopolymer blend, using various combinations of PLA/PHBV including 25/75, 50/50 and 75/25 wt% a hybrid biopolymer blend was prepared. Among them, PLA-PHBV (75/25 wt%) with 2 wt% nanoclay resulted in the best outcome. The tensile strength of this prepared polymer blend was 29.34 MPa. Thermal analysis demonstrated two melting temperatures: 238.37 °C and 308.31 °C, respectively. Two glass transition temperatures were found from thermal tests which are the indication of the solution immiscibility. It had also been observed that the adding of nanoclay enhances tensile properties as well as thermal stability up to 2 wt%. It is revealed from the optical and SEM micrographs that the 2 wt% NC was dispersed uniformly throughout the resin blend.