Biodegradation of LDPE/banana starch films compatibilized with ethylene vinyl acetate copolymer

Abstract

This research investigated the effects of starch and compatibilizer contents on tensile properties and biodegradability of new polymer blend films from low-density polyethylene (LDPE) and starch. The compatibilizer used in the blends was ethylene vinyl acetate copolymer (EVA). Banana starch was used in this study. Dried banana starch of 0-20% w/w of LDPE and EVA of 0, 5. 10, 20% w/w of banana starch were added to the LDPE. After film formation, physical and tensile properties of the films were examined. The biodegradation of LDPE/banana starch films was performed by activated sludge and enzymatic degradation methods. Biodegradation process was followed by measuring the changes in weight loss, physical appearance, and tensile properties. The results showed significant effects of banana starch and EVA contents on the biodegradability, thermal properties, and tensile properties of the blend films. The biodegradation rate increased with increasing amount of starch, while tensile properties of the films decreased. In particular, the degradation rate of the films exposed to enzymatic degradation was higher than those subjected to activated sludge. The addition of EVA in the polymer blends led to an increase in tensile properties and thermal stability whereas the biodegradability of the films was slightly decreased compared to the films without EVA.