Ácido itacônico como compatibilizante em filmes de amido e poliéster produzidos por extrusão reativa

Abstract

The accumulation of plastic packaging is worrying society worldwide, so aiming at environmental preservation, biodegradable polymers represent one of the ways to minimize the environmental impacts In the production of biodegradable polymer blends, factors such as miscibility and compatibility must be considered. In this study, itaconic acid in different concentrations (0, 0.25, 0.5, 0.75 and 1.0 g 100g-1 (total mixture)) was used as compatibilizer in cassava starch films and Poly (adipate co-butylene terephthalate) (PBAT) plasticized with glycerol, and produced by extrusion-blowing in two steps: production of pellets and production of the film. The films were characterized for thickness, transverse stretching, apparent opacity, mechanical properties, humidity, water solubility and water vapor permeability. The thickness of the films vary from 194.39 to 230,72μm. Only the formulation containing 0.5% (m / m) of itaconic acid produced films with significantly higher transverse stretching the film control. In general, the presence of itaconic acid produced films with a lower opacity when compared to the film without compatibilizer. The presence of itaconic acid at concentrations of 0.25 and 0.5% (w / w) significantly decreased the tensile strength of the films in relation to the film strength control values, highlighting possible hydrolytic effect of the acid on the polymer chains. However, at these concentrations, the films retained their stiffness and flexibility characteristics when compared to the film without addition of a compatibilizer. All formulations containing itaconic acid showed values of solubility in water higher than the control film, and only the formulation with 1.0% (w / w) was significantly more soluble in water. The permeability to water vapor, the formulation 0.25 AI was significantly higher than that observed for the control film, where as formulations with higher concentrations of compatibilizer, 0.75 and 1.0% (w / w) produced films Low permeability to water vapor. So, the presence of itaconic acid in different concentrations did not affect the production of PBAT and starch films plasticized with glycerol and produced by extrusion blow homogeidade and showing good handleability. In that enables the concentration of 0.75% AI (w/w) is most appropriate for producing films with improved mechanical performance, since more rigid film form without significant loss in elongation at break.