Comparative Study on Properties of PBAT/PBSA Film Modified by a Multi-Functional Epoxide Chain Extender or Benzoyl Peroxide

Poly(butylene adipate-co-terephthalate) (PBAT) and poly(butylene succinate-co-adipate) (PBSA) blend films were prepared with different contents of a multifunctional epoxide chain extender Joncryl ADR-4468 (ADR) or benzoyl peroxide (BPO). The long-chain-branching (LCB) introduced by ADR and branched/crosslinked entanglement induced by BPO increased melt elasticity, viscosity and compatibility, as indicated by thermal properties, rheological and morphological analyses. It was found that the elongation at break and the tensile strength were significantly improved, due to the enhancement of compatibility and the interfacial adhesion by the incorporation of ADR or BPO. The best mechanical properties were obtained in PBAT/PBSA/ADR (60/40/0.3) (A4T6A0.3) and PBAT/PBSA/BPO (60/40/0.9) (A4T6B0.9) films, respectively. With the rapid initiation of chain growth by BPO, it has significantly improved the transparency of the film. ADR and BPO can be used interchangeably in improving the comprehensive properties of PBAT/PBSA films, and it would provide more strategies for developing biodegradable materials for various applications.