Polybutylene adipate terephthalate/polylactic acid interface enhanced compatibilization and its bead-foaming characteristics

Bead foaming technique is regarded as a highly promising method for preparing foams with complex geometries and high expansion ratios. The biodegradability of poly(butylene adipate-co-terephthalate) (PBAT) has garnered significant attention in the field of foam materials. However, due to inherent disadvantages such as low melt strength and low modulus, PBAT faces challenges during bead foaming. In this study, a small amount of polylactic acid (PLA) was incorporated into PBAT. Utilizing the differential melting points of PLA and PBAT, PLA served as physical cross-linking points. The epoxy-based chain extender ADR4370S was used as a chain extender and compatibilizer. By varying its content, the compatibility and foaming performance of the PBAT/PLA blend were regulated. Finally, the foaming process employed supercritical carbon dioxide (scCO