Physical and Mechanical Properties of Poly(Butylene Succinate) and Poly(Lactic Acid) under Landfill Conditions

Abstract

In this study, the disintegration of poly(butylene succinate)(PBS) and poly(lactic acid) (PLA) under landfill conditions was investigated. Both polymers were melted, injected into a dumbbell-shape, and buried under the soil for 20 weeks. The morphology of the polymer from the scanning electron microscope (SEM) revealed that, after 6 weeks of the burial, the PBS polymer produced many micro-voids in the bulk of polymer. The amount of the voids increased with time. While the morphology of PLA showed a few voids and some cracks during the degradation process. Moreover, the mechanical properties of the PLA were decreased after 2 weeks following with PBS after 4 weeks of the burial times. The weight loss and the water uptake of PBS and PLA were slightly increased. From the result, it was found that the degradation of PBS and PLA proceeds via random chain scission of the ester bond through bulk erosion mechanism. The degradation of PLA degraded faster than the PBS due to the low crystallinity in the polymer chain. This result can be applied to the design waste management of biodegradable polymer products.