College of Chemistry and Molecular Sciences, Wuhan University , Wuhan 430072, China.
Yangtze Valley Water Environment Monitoring Center, Wuhan 430072, China.
ACS Appl Mater Interfaces. 2017 Jul 19;9(28):24230-24237. doi: 10.1021/acsami.7b06219. Epub 2017 Jul 5.
The weak mechanical properties of hydrogels usually limited their application in biomedical and industrial fields. Herein, we reported a nanocomposite network of poly(acrylic acid-co-acrylamide) (PAAAM) sequentially cross-linked by quaternized tunicate cellulose nanocrystals (Q-TCNCs) and Fe. Q-TCNCs acted as both interfacial compatible reinforcements and cross-linkers in the nanocomposite hydrogels to form loose cross-linking, whereas compact cross-linking was built by ionic coordination between Fe and -COO of PAAAM. The toughness of dual cross-linked hydrogel (D-Gel) was 340 times that of mono-cross-linked hydrogel (m-Gel), which was 10 times that of PAAAM hydrogel. Moreover, the nanocomposite hydrogels exhibited excellent self-recoverability after treating the stretched samples in FeCl aqueous solution. This work provided a universal strategy for construction of tough nanocomposite hydrogel reinforced with cellulose nanocrystals.
水凝胶的力学性能较弱，通常限制了它们在生物医学和工业领域的应用。在此，我们报道了一种聚（丙烯酸-co-丙烯酰胺）（PAAAM）的纳米复合网络，该网络通过季铵化海鞘纤维素纳米晶（Q-TCNC）和 Fe 依次交联。Q-TCNC 既作为界面相容增强剂，又作为纳米复合水凝胶中的交联剂，形成疏松交联，而通过 Fe 与 PAAAM 的-COO 之间的离子配位则形成紧密交联。双交联水凝胶（D-Gel）的韧性比单交联水凝胶（m-Gel）高 340 倍，比 PAAAM 水凝胶高 10 倍。此外，在 FeCl 水溶液中处理拉伸后的样品后，纳米复合水凝胶表现出优异的自恢复性。这项工作为构建具有纤维素纳米晶增强的坚韧纳米复合水凝胶提供了一种通用策略。
