PAM/OSA/PVA hydrogel was prepared by simple copolymerization using acrylamide (PAM), oxidized sodium alginate (OSA), and poly (vinyl alcohol) as monomers. The hydrogel exhibited a quadruple-shape memory effect based on imine, coordination, and borate bonds. Self-healing properties of the quadruple-shape memory hydrogel were observed to evolve due to the imine and borate bonds. The hydrogel demonstrated tunable mechanical properties because of supramolecular interactions including OSA –Ca 2+ , PVA –borax, and OSA –PAM in different conditions. The new hydrogel is envisaged to increase the variety as well as broaden the design and manufacturing of shape memory hydrogels. Graphical abstract Dual multi-shape memory images of PAM/OSA/PVA hydrogel and its shape memory mechanism.

中文翻译：

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基于亚胺、配位和硼酸盐键的自修复四重形状记忆水凝胶，具有可调机械性能

以丙烯酰胺 (PAM)、氧化海藻酸钠 (OSA) 和聚乙烯醇为单体，通过简单共聚制备 PAM/OSA/PVA 水凝胶。水凝胶表现出基于亚胺键、配位键和硼酸盐键的四重形状记忆效应。观察到由于亚胺和硼酸盐键，四重形状记忆水凝胶的自愈性能发生了变化。由于包括 OSA –Ca 2+ 、PVA –硼砂和 OSA –PAM 在不同条件下的超分子相互作用，水凝胶表现出可调的机械性能。预计这种新的水凝胶将增加形状记忆水凝胶的种类并拓宽其设计和制造范围。PAM/OSA/PVA 水凝胶的图形抽象双重多形状记忆图像及其形状记忆机制。