Effect of
ADR
Series Chain Extender and
PEG
on the Properties of
PLA
‐Based Shape Memory Composit
Chengxue Li, Chunhui Zhang, Jianhong Liu, Mengge Huang, Hongwu Zhou, Yixuan Zhang, Yubing Dong ABSTRACT
To improve the elongation at break of poly (lactic acid) (PLA) and retain its shape memory properties, in this study, polyethylene glycol (PEG) was employed as a plasticizer and incorporated chain extenders ADR‐4370 and ADR‐4400. The effects of PEG and chain extender on the microstructure, mechanical properties, shape memory properties, thermal properties, stability, and optical properties of the ADR/PEG/PLA films were investigated. The results showed that the chain extenders improved the interfacial compatibility and further increased the elongation at break. The shape memory recovery ratio ( R r ) of the films was highest at a recovery temperature of 80°C. The composite films with higher PEG molecular weight exhibited better shape memory performance. With increasing ADR‐4370 content, R r first increased and then decreased, whereas with increasing ADR‐4400 content, R r increased continuously, and orientation‐induced crystallization was generated. PEG promoted PLA crystallization; chain extender‐induced chain extension/branching and interfacial coupling inhibited crystal growth. ADR‐4370 enhanced the thermal stability of the films at the high‐temperature stage, and ADR‐4400 improved the thermal stability at the initial stage. UV–Vis spectroscopy showed that the ADR‐4370‐modified films exhibited significantly enhanced UV shielding and markedly reduced visible‐light transparency, whereas ADR‐4400 caused relatively small changes.