A novel polymer based on ethylene-methyl acrylate copolymer/chloroprene rubber thermoplastic vulcanizates with rapid thermo-responsive shape memory property

A simple and effective strategy for preparing thermo-responsive shape memory polymers (TSMPs) can be designed where the novel TSMPs based on ethylene-methyl acrylate copolymer (EMA) and chlorinated polyethylene rubber (CR) thermoplastic vulcanizates (TPVs) were prepared using dynamic vulcanization. The morphology of the EMA/CR TPVs exhibited a sea-island structure obviously; moreover, the EMA served as the continuous phase and mainly provided the shape fixation (SF) capability of the blend, while the highly elastic CR was acted as the dispersed phase and provided the primary driving force during the shape recovery (SR) process. The SF and SR behaviors of the EMA/CR TPVs can be effectively controlled by varying the weight ratio of EMA/CR blends. Increasing the weight ratio of EMA/CR, the SF% of the EMA/CR TPVs was enhanced while the SR% was decreased remarkably. The shape memory behaviors of EMA/CR TPVs were significantly influenced by temperature. Notably, when the fixation and recovery temperatures were all set at 95°C, both the SF% and SR% of the EMA/CR TPVs with a weight ratio of 80/20 exceeded 95%, and the SR time was 15∼20s, demonstrating the excellent shape memory property.