Biodegradation and Mechanical Properties of Poly(lactic acid)/Poly(butylene succinate) Blends

Abstract

Polymer blends were fabricated with poly(lactic acid) (PLA) with better mechanical properties and poly(butylene succinate) (PBSU) with better biodegradable properties to clarify the effect of the blending ratio on the biodegradable and mechanical properties of the blends. The specimens were heat treated to improve the reduction in stiffness due to blending. Hydrolysis and soil burial tests up to 16 weeks were conducted to investigate the biodegradation properties. Young's modulus increased with increasing contents of PLA, whereas tensile strength is lowest in the PLA/PBSU (50/50) polymer blend before biodegradation because of the immiscibility of PLA and PBSU. Young's modulus kept constant up 16 weeks both in the hydrolysis and the soil burial tests. On the other hand, tensile strength decreased remarkably in the hydrolysis tests. The observation results of the specimen surface and the fracture surface indicate that the surface and bulk degradation occur in hydrolysis and soil burial tests, respectively