刺激响应性聚甲基丙烯酸二甲氨基乙酯水凝胶

Stimuli-Responsive Poly (N,N-Dimethylaminoethyl Methacrylate) Hydrogels

以二甲基丙烯酸乙二醇酯为交联剂,甲基丙烯酸-N,N-二甲氨基乙酯为单体,分别采用普通自由基聚合和原子转移自由基聚合合成交联聚甲基丙烯酸-N,N-二甲氨基乙酯(PDMAEMA)。由于PDMAEMA同时呈现温度、pH和离子强度敏感性,文中研究了离子强度、pH值对交联PDMAEMA在水溶液中的溶胀比、体积相转变温度(TVPT)的影响。实验结果表明,PDMAEMA水凝胶的溶胀度随着离子强度和pH值的增大而减小;溶液离子强度的改变导致体系中的水状态发生改变,TVPT也随之改变;在酸性条件下TVPT随着pH值的增加而降低。

The crosslinked PDMAEMA was prepared via conventional radical polymerization and atom transfer radical polymerization（ATRP） by using ethylene glycol dimethacrylate（EGDMA） and 2-（N,N-dimethylamino） ethyl methacrylate （DMAEMA）（the EGDMA was used as cross-linking agent）.The swallen PDMAEMA hydrogels exhibited lower critical solution temperature（LCST） behavior and pH,temperature,ionic strength-sensitive.The DSmax of the PDMAEMA hydrogels and the volume transition temperature（TVPT） of the PDMAEMA hydrogels in the aqueous solution were studied in terms of electrolyte concentration and pH value.The results show that the DSmax of PDMAEMA decreases with the increase of the ionic strength and pH,the TVPT changes with the ionic strength and decreases with the increase of the pH under acid condition.