Biodegradation of aliphatic polyesters by soil burial tests and enzymatic degradation in solution

The biodegradability of high molar mass poly(butylene succinate-co-butylene sebacate), P(BSu-co-BSe), and poly(butylene succinate-co-butylene adipate), P(BSu-co-BAd), samples, with different composition, was investigated under controlled soil burial conditions. Film samples were also assayed to enzymatic attack by Lipase from Mucor miehei or from Rhizopus arrhizus. The relative normalised weight loss rates were compared. The influence of crystallinity, molar mass, chemical structure and melting temperature upon biodegradation was studied. The weight loss of poly(3-hydroxy butyrate), P(HB), of poly(3-hydroxy butyrate-co-3-hydroxy valerate) 76/24, P(HB-co-HV) 76/24, and of two Bionolle commercial samples, was also investigated under soil burial conditions. The results allow a direct comparison of the soil burial degradability of polyesters having different structures.