State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.
College of Engineering, Qufu Normal University, RiZhao 276826, China.
Carbohydr Polym. 2017 Dec 15;178:159-165. doi: 10.1016/j.carbpol.2017.09.030. Epub 2017 Sep 11.
A novel multivalent cations-triggered shape memory hydrogels were synthesized in a one-pot method, and interpenetrating double network was formed by chemically cross-linked polyacrylamide (PAM) network and physically cross-linked sodium carboxymethyl cellulose network. The temporary shape was fixed by complexation between a native biopolymer, sodium carboxymethyl cellulose (CMC), and transition metal ions, specifically Fe, Ag, Al, Cu, Ni, and Mg. In particular, CMC-Fe hydrogel exhibits excellent shape fixity ratio (95%). Therefore, we chose PAM/CMC-Fe hydrogel as the model material and further investigated its shape recovery process. It was found that a wide range of molecules and anions could be applied to break off the temporary cross-links between CMC and Fe. The PAM/CMC composite hydrogels also exhibited excellent tunable mechanical properties. The mechanical properties of the composite hydrogel can be adjusted by changing the cross-linking densities. The presented strategy could enrich the construction as well as application of biopolymers based shape memory hydrogels.
一种新型的多价阳离子触发形状记忆水凝胶通过一锅法合成，通过化学交联的聚丙烯酰胺（PAM）网络和物理交联的羧甲基纤维素钠网络形成互穿双网络。临时形状通过天然生物聚合物羧甲基纤维素钠（CMC）与过渡金属离子（特别是 Fe、Ag、Al、Cu、Ni 和 Mg）之间的络合固定。特别是，CMC-Fe 水凝胶表现出优异的形状固定率（95%）。因此，我们选择 PAM/CMC-Fe 水凝胶作为模型材料，并进一步研究了其形状恢复过程。结果发现，广泛的分子和阴离子可用于破坏 CMC 和 Fe 之间的临时交联。PAM/CMC 复合水凝胶还表现出优异的可调机械性能。通过改变交联密度可以调节复合水凝胶的机械性能。所提出的策略可以丰富基于生物聚合物的形状记忆水凝胶的构建和应用。
