通过两步自由基聚合法成功制备了纳米蒙脱土复合双网络水凝胶。蒙脱土与阳离子单体进行离子交换后以离子键作用于凝胶网络体系成为化学交联点,同时吸附大分子链作为水凝胶的物理交联点。双网络结构进一步提高凝胶的机械性能。力学性能结果表明,随着蒙脱土含量增加,水凝胶的杨氏模量、拉伸强度、压缩模量以及压缩强度提高,同时增加第一网络单体浓度,双网络水凝胶的机械性能进一步提高。扫描电镜微观形貌分析表明,蒙脱土的加入促进水凝胶的网络结构更加紧密,并形成大量的纤维状微网络结构,由此,水凝胶的力学性能明显提高。抑菌实验表明,因含有季铵盐阳离子,水凝胶对大肠杆菌以及金黄色葡萄球菌都具有良好的抑菌效果。
(3-Acrylamidopropyl)trimethylammonium chloride (ATC), acrylamide and montmorillonite (MMT) without organic modification were synthesized through free radical polymerization to strengthen the mechanical properties of hydrogels. MMT platelets were considered as chemical "plane" cross-linkers different from "point" cross-linkers because of the cation-exchange reaction between MMT and ATC (cationic monomer) during the synthesis of hydrogels, while a double network was used to improve the mechanical properties of the hydrogels. Investigations of compressive and tensile properties indicated that compressive modulus and stress, fracture stress, ultimate strain and Young's modulus were significantly improved in the presence of MMT. The mechanical properties of double-network hydrogels improved with increasing monomer concentration of the first network. Scanning electron microscopy (SEM) revealed that large quantities of micro-network structures were located in the pores and the formation of embedded micro-network structures led to an increase in the compressive strength and toughness. Moreover, the gels with ATC exhibited good antibacterial effects against E. coil and S. aureus. These developments provide a new route to prepare hydrogels with high mechanical properties.