Synthesis of Highly Stretchable, Mechanically Tough, Zwitterionic Sulfobetaine Nanocomposite Gels with Controlled Thermosensitivities
Synthesis of Highly Stretchable, Mechanically Tough, Zwitterionic Sulfobetaine Nanocomposite Gels with Controlled Thermosensitivities
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DOI：
10.1021/ma4009059
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发表时间：
2013-07-09
期刊：
影响因子：
5.5
通讯作者：
Haraguchi, Kazutoshi
中科院分区：
文献类型：
--
作者：
Ning, Jinyan;Li, Guang;Haraguchi, Kazutoshi
在水介质中，以片状粘土为模板，通过磺基甜菜碱单体的原位自由基聚合制备了具有两性离子特性的新型纳米复合凝胶。两个特定的磺基甜菜碱单体，N，N-二甲基（丙烯酰胺丙基）铵丙磺酸盐和丁磺酸盐，选择的基础上的单体和粘土之间的相互作用，这导致在不使用有机交联剂的低粘度和凝胶形成的均匀的水溶液。与传统的物理交联凝胶不同，所得到的具有聚合物-粘土网络结构的NC凝胶不溶于NaCl溶液或热水。此外，NC凝胶具有高的机械性能和良好的控制热敏性，有效地制备通过共聚与少量的N，N-二甲基丙烯酰胺。共聚物NC凝胶是均匀的，同时表现出高的拉伸性，坚韧机械性能，以及定义明确的上临界溶解温度（UCST）的相变。此外，通过改变粘土浓度和共聚比，可在较宽范围内控制拉伸力学性能和UCST。
Novel nanocomposite (NC) gels with zwitterionic characteristics were prepared by in situ free-radical polymerization of sulfobetaine monomers in the presence of exfoliated clay platelets in aqueous media. Two specific sulfobetaine monomers, N,N-dimethyl(acrylamidopropyl)ammonium propanesulfonate and butanesulfonate, were selected on the basis of the interactions between the monomers and clay, which result in uniform aqueous solutions of low viscosity and gel formation without using an organic cross-linker. The resulting NC gels with polymer-clay network structures were insoluble in NaCl solution or hot water, unlike conventional physically cross-linked gels. Also, NC gels with high mechanical properties and well-controlled thermosensitivities were effectively prepared by copolymerization with a small amount of N,N-dimethylacrylamide. The copolymer NC gels were uniform and simultaneously showed high stretchability, tough mechanical properties, and well-defined upper critical solution temperature (UCST) phase-transitions. Furthermore, the tensile mechanical properties and UCST were controlled over a wide range by altering the clay concentration and copolymerization ratio.