In this work, a triple-shape memory polymer (SMP) was prepared by chemically crosslinking melting blending from ethylene-vinyl acetate copolymer (EVA) and poly(propylene carbonate) (PPC). The EVA/PPC blends combine the glass transition of PPC (~25.6 °C) and melting transition of EVA (~72.2 °C) to function as the shape memory mechanisms. The triple-shape memory effect (triple-SME) and its dependence on composite ratios and micro-phase morphologies were systematically investigated. The results show that EVA/PPC blends with different composite ratios and morphologies all exhibit excellent triple-SMEs, with shape fixing ratio over 90% and shape recovery ratio close to 90%. The key to realize such triple SME is the certain matching of the modulus of the two components. Specifically, the modulus of glassy PPC is much higher than the modulus of semi-crystalline EVA, whereas the modulus of viscoelastic PPC is lower than the modulus of semi-crystalline and elastic EVA. This work provides a comparatively simple and efficient method to design and prepare high-performance triple-SMP.

在这项工作中，通过将乙烯-醋酸乙烯酯共聚物 (EVA) 和聚碳酸丙烯酯 (PPC) 化学交联熔融共混制备了三重形状记忆聚合物 (SMP)。EVA/PPC 混合物结合了 PPC 的玻璃化转变 (~25.6 °C) 和 EVA 的熔融转变 (~72.2 °C)，起到形状记忆机制的作用。系统地研究了三重形状记忆效应（triple-SME）及其对复合比和微相形态的依赖性。结果表明，不同复合比和形貌的EVA/PPC共混物均表现出优异的三重SMEs，定型率超过90%，形状恢复率接近90%。实现这种三重 SME 的关键是两个分量的模数的一定匹配。具体来说，玻璃态 PPC 的模量远高于半结晶 EVA 的模量，而粘弹性 PPC 的模量低于半结晶和弹性 EVA 的模量。这项工作为设计和制备高性能三重 SMP 提供了一种相对简单有效的方法。