Degradation of Poly(lactic acid) and Poly(butylene adipate-co-terephthalate) Blends in Compost

Geotextiles are used extensively to protect soil from erosion. In this study, we evaluated the mechanical properties and degradation behaviors of poly(lactic acid)/poly(butylene adipate-co-terephthalate) (PLA/PBAT) blends. The incorporation of PBAT to PLA decreased the tensile strength and modulus but increased the elongation at break of the blends. Tensile strength and elongation of the PLA/PBAT blend resins were dramatically improved by incorporating a chain extender. When PLA/PBAT blends were composted under $35^{\circ}C$, 90% RH conditions, they showed two-stage degradation and completely lost their mechanical properties after 40 weeks. The PBAT-dominant blend (PLA/PBAT 40/60) showed slightly slower degradation than the PLA-dominant blend (PLA/PBAT 60/40).