Evaluation of the biodegradability of poly (butylene adipate-co-terephthalate) and cassava starch films in municipal compost under controlled conditions by analysis of evolved carbon dioxide

Abstract

Plastic waste pollution is a major environmental issue all over the world, with Vietnam ranking among the ten most polluted countries. As a result, it is critical that research aims to reduce pollution levels from this plastic waste resource through the fabrication and application of biodegradable polymers to replace traditional plastics. In this study, plastics blend film based on cassava starch/poly(butylene adipate-co-terephthalate) (TPS/PBAT) (ratio of 40/60) was fabricated in a reactive twin screw extruder. Testing methods following the ASTM 6400 standard were used to evaluate the biodegradability of the film based on the TPS/PBAT blend shown that under controlled aerobic composting conditions (temperature of 58°C and humidity of 55%), the biodegradation rate of the film, calculated according to the amount of CO₂ produced, reached of 91% after 155 days, and the disintegration degree of 96% after 53 days. The rate of bean and cucumber germination on the resulting compost demonstrates satisfactory terrestrial safety. The results of this study confirmed that TPS/PBAT film is a highly compostable material that can be used to improve the biodegradability of products like munch films, supermarket bags, seedling bags, and garbage bags.