O objetivo deste trabalho foi produzir filmes biodegradáveis à base de álcool polivinílico (PVA) e, também avaliar o efeito dos diferentes graus de hidrólise (DH) e graus de polimerização (DP) do PVA nas propriedades desses filmes. Quatro tipos diferentes de PVA com DH variando de 88,0 a 98,4% e DP variando de 150 a 2000 foram utilizados para produzir os filmes por casting, e o glicerol foi usado como plastificante. Os filmes formulados com PVA com menor DH (SelvolTM 540 e 203) apresentaram maior solubilidade, permeabilidade ao vapor de água e capacidade de absorção de água, além de serem menos rígidos e apresentarem menores temperaturas de transição vítrea e de fusão quando comparados aos filmes obtidos com PVA com maior DH (SelvolTM 325 e 107). O DP afetou a solubilidade dos filmes, o filme produzido com PVA com maior DP (SelvolTM 325 - DP = 1000????1500) apresentou menor valor de solubilidade. Os filmes formulados com PVA com maior DP (SelvolTM 540 e 325) apresentaram maiores valores de elongação na ruptura. Tanto o DH quanto o DP afetaram as propriedades dos filmes de PVA, resultando em materiais com diferentes possibilidades de aplicação, no entanto, observou-se que o efeito do DH foi mais importante para as propriedades dos filmes de PVA do que o efeito DP.

Studies using starch to produce biodegradable materials have proved attractive due to its availability and low cost in relation to commercial biodegradable polymers, such as poly (lactic acid) and others. Starch-based materials do not have adequate mechanical properties for production and use on a commercial scale, requiring mixtures (blends) with other biodegradable polymers to improve these properties. However, these blends need compatibilizers due to the immiscibility between the starch and the polymer. The present work aimed to study the effect of different compatibilizers (3-(trimethoxysilyl) propyl methacrylate, citric acid, and maleic anhydride) on the functional properties of biodegradable starch and poly (lactic acid) (PLA) materials produced by extrusion and thermoplastic injection. Citric acid was considered the best compatibilizer for these materials because it improved the processability, and the materials presented properties suitable for applications where good mechanical resistance is required. In addition, the materials containing citric acid and maleic anhydride were more uniform from the morphological point of view.

Fossil-origin plastics have raised great concerns due to their non-biodegradable nature. Biodegradable polymers can be an alternative for these materials’, however they have higher cost. The use of agro-industrial waste in blends with biopolymers can provide cheaper materials’ with improved properties. This study aims to develop low-cost biodegradable materials by extrusion and thermoplastic injection using oat hulls, polybutylene succinate (PBS), and starch. Six formulations with different concentrations of oat hulls (0-56% w/w) were extruded in a single-screw extruder, and then the materials were produced by thermoplastic injection. The extrusion aligned the oat hull fibers, making the material dimensionally stable. The oat hulls enhanced stiffness and reduced material density compared to non-hull counterparts. Besides that, the oat hulls are a low-cost agro-industrial byproduct, and it was possible to produce biodegradable materials with up to 56% hulls and only 20% PBS. These biodegradable materials are environmentally friendly and non-toxic.

The increasing concern regarding the environmental impact of conventional plastics has intensified the search for sustainable alternatives. This study investigated the development and characterization of biocomposites produced from glue flour (GF), a wheat milling by-product, and poly(butylene succinate) (PBS) using injection molding. GF/PBS ratios of 100/0 (PBS0), 80/20 (PBS20), 70/30 (PBS30), and 60/40 (PBS40) (w/w) were evaluated in terms of physical, mechanical, and thermal properties. The results showed that increasing the PBS content significantly enhanced tensile strength from 1.36 MPa (PBS0) to 12.23 MPa (PBS40) and Young’s modulus from 0.12 MPa to 1.54 MPa. Water solubility decreased from 37.03% (PBS0) to 16.08% (PBS40), and linear shrinkage was reduced from 5.5% (PBS0) to around 2.0% (PBS40). Scanning electron microscopy (SEM) analysis revealed improved homogeneity and reduced granule visibility with higher PBS concentration. Fourier transform infrared spectroscopy (FTIR) spectra indicated intensified interactions between starch, proteins, and PBS as its content in the formulation increased. Thermal analysis revealed that biocomposites containing PBS exhibited well-defined melting (Tm ~115 °C) and crystallization (Tc ~80 °C) temperatures, indicating more consistent thermal behavior than the PBS-free sample. These findings suggest that GF/PBS biocomposites have strong potential as sustainable alternatives to conventional plastics, offering viable applications across various industrial sectors.