The shape memory properties of olefin block copolymer (OBC)/polycaprolactone (PCL) crosslinked blends at different blend compositions were investigated. This is the first OBC-based two-way shape memory blends processes without external load under thermal and vapor stimuli. The deformation temperature of 80 °C was selected far away between the respective melting temperatures of PCL (56.5 °C) and OBC (110.3 °C) for the thermo-triggered two-way multiple shape memory behavior. The internal stress developed between the unmelted OBC crystalline region and crystallized PCL during cooling under pre-strain conditions played an important role in further melting-induced contraction and cooling-induced elongation without external load, even though the deformation temperature caused the complete melting of the crystalline region of PCL and the crystallinity of unmelted OBC was very small. As for the solvent vapor-triggered cases, the THF and n-hexane solvents were used. The bent sample shrank in response to the vapor stimulation, followed by expanding in the air. The blends remarkably showed rare solvent vapor-triggered reversible shape memory behavior without any external stress and pre-soaking treatment. This interesting finding was not reported earlier until now, to the best of our knowledge. This current finding unveils numerous possibilities to prepare multi-triggered blending systems with reversible shape memory behavior.

研究了烯烃嵌段共聚物 (OBC)/聚己内酯 (PCL) 交联共混物在不同共混物组成下的形状记忆性能。这是第一个基于 OBC 的双向形状记忆混合过程，在热和蒸汽刺激下没有外部负载。对于热触发的双向多形状记忆行为，80°C 的变形温度被选为远离 PCL (56.5°C) 和 OBC (110.3°C) 的各自熔化温度。在预应变条件下冷却期间未熔化的 OBC 结晶区域和结晶的 PCL 之间产生的内应力在没有外部载荷的情况下进一步熔化诱导收缩和冷却诱导伸长中起着重要作用，即使变形温度导致 PCL 的结晶区完全熔化，未熔化的 OBC 的结晶度很小。对于溶剂蒸汽触发的情况，THF 和Ñ使用己烷溶剂。弯曲的样品在蒸汽刺激下收缩，然后在空气中膨胀。该共混物在没有任何外部应力和预浸处理的情况下显着显示出稀有溶剂蒸汽触发的可逆形状记忆行为。据我们所知，这个有趣的发现直到现在才被更早地报道。目前的这一发现揭示了制备具有可逆形状记忆行为的多触发混合系统的多种可能性。