快速响应的聚(N-异丙基丙烯酰胺)水凝胶的合成及性能

以羧甲基纤维素的水溶液为反应介质制备了快速响应的温度敏感性聚(N-异丙基丙烯酰胺)水凝胶。利用DSC对其相转变温度进行了表征,并测定了不同温度下达到平衡时水凝胶的溶胀比,研究了水凝胶的去溶胀动力学。结果表明,在聚合/交联过程中羧甲基纤维素的存在对PN IPA水凝胶的相转变温度几乎没有影响;与传统水凝胶相比,该水凝胶的溶胀性能有所提高,并且具有较快的响应速率。

Synthesis and Properties Study of Poly(N-isopropylacrylamide) Hydrogel with Fast Response Rate

Thermo-sensitive poly(N-isopropylacrylamide)(PNIPA) hydrogel was prepared by polymerization in aqueous carboxymethyl cellulose solution.The volume phase transition temperature of PNIPA hydrogels was characterized utilizing differential scanning calorimetre.The swelling ratios of the hydrogels at different temperatures were measured.Furthermore,the deswelling kinetics of the hydrogels was also studied through measuring their water retention.The result indicates that the presence of carboxymethyl cellulose during the polymerization/cross-linking process has little effect on the lower critical solution temperature of the PNIPA.In addition,in comparision with a conventional PNIPA hydrogel prepared in water,the hydrogel had higher swelling ratios at temperatures below the lower critical solution temperature and exhibited much faster response rate to temperature changes.KH 1mmD]