冷冻聚合法制备多孔P(NIPAm-Co-AAm)水凝胶及其性能研究  

The property study of porous P(NIPAm-co-AAm) hydrogels prepared by freezing polymerization

作　　者：杨桔[1] 霍丹群[1] 侯长军[1,2] 杨眉[1] 张国平[1] 张玉婵[1] 董家乐[1] 

机构地区：[1]重庆大学生物工程学院,生物流变科学与技术教育部重点实验室,重庆400044 [2]重庆大学新型微纳设备与系统技术国防学科重点实验室/光电技术与系统教育部重点实验室微系统中心,重庆400044

出　　处：《功能材料》2011年第2期343-346,350,共5页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(30770568);重庆市科委重点攻关资助项目(2008AB2024);重庆市科委攻关资助项目(2008AC7037);教育部留学回国基金资助项目((2006)331);中国高校基本科研业务资助项目(CDJXS10231119);“211工程”研究生开放实验室资助项目(S-09104)

摘　　要：采用冷冻聚合法制备了多孔结构的P(NI-PAm-co-AAm)智能水凝胶,利用扫描电子显微镜和比表面积分析仪对水凝胶的多孔结构和表面形貌进行了测试,并测定了水凝胶的平衡溶胀比、溶胀和退溶胀动力学,研究了不同预冷冻聚合时间对水凝胶温度响应速率的影响,并且与传统方法制备的P(NIPAm-co-AAm)水凝胶进行了响应速率对比试验。实验结果表明,冷冻聚合法制备的多孔P(NIPAm-co-AAm)水凝胶其温度响应速率得到显著的提高,与传统方法合成的水凝胶相比,冷冻聚合法合成的水凝胶具有更为贯通的开孔结构,这些相互贯通的开孔结构为水分子进出水凝胶提供了通道,从而可提高凝胶的温度响应速率;预冷冻聚合时间对多孔P(NIPAm-co-AAm)水凝胶的温度敏感性能影响很大,P(NIPAm-co-AAm)水凝胶的平衡溶胀率(SR)随着时间的延长而减小,其最低临界相转变温度(LCST)受预冷冻聚合时间的影响不大,几乎都在35℃左右;温度响应速率随着预冷冻聚合时间的增大而减慢。Porous poly（N-isopropylamide-co-acrylamide） [P（NIPAAm-co-AAm）] hydrogels with a very fast thermo-responsive rate were prepared by freezing polymerization method.The internal pore structure and surface morphology of hydrogels were observed by surface area analyzer and scanning electron microscope.The equilibrium swelling ratio and the swelling/deswelling kinetics of the hydrogels were investigated.The influence of reaction time of the pre-freezing polymerization on the thermo-responsive rate of the hydrogels was also studied.The results showed that the interconnecting porous network structure had been successfully prepared by the freezing polymerization method.These open pore structures are very useful to accelerate the responsive rate of the hydrogel.The results of swelling properties show that the time of pre-freezing polymerization play a dominant role in the final properties of P（NIPAAm-co-AAm） hydrogel.The equilibrium swelling ratio（SR） of hydrogels reduced with reaction time of pre-freezing polymerization increasing.The lowest critical phase transition temperature（LCST） of P（NIPAm-co-AAm） hydrogels were all around 35 ℃,and different reaction time of pre-freezing polymerization have little effect on it.The swelling/deswelling rate decreased with the reaction time of the pre-polymerization polymerization increasing.

关 键 词：冷冻聚合法 多孔 温敏水凝胶 N-异丙基丙烯酰胺 

分 类 号：TB317.3[一般工业技术—材料科学与工程]