温度和pH双重敏感性P(DEA-co-DMAEMA)/Na2WO4水凝胶的合成与表征

Synthesis and Characterization of Temperature and pH Sensitivity P(DEA-co-DMAEMA)/Na2WO4 Hydrogels

摘要:

以N,N-二乙基丙烯酰胺（DEA）和甲基丙烯酸二甲氨基乙酯（DMAEMA）为单体，N,N-亚甲基双丙烯酰胺（BIS）为交联剂，采用一锅法制备了温度和pH双重响应性P(DEA-co-DMAEMA)/Na2WO4水凝胶。研究了Na2WO4的引入对水凝胶的结构、温度和pH响应性能的影响。结果表明：复合水凝胶中除了化学交联以外，还存在Na2WO4与聚合物间由于氢键和配位作用产生的物理交联；复合水凝胶的LCST随着Na2WO4含量增加呈线形降低，当Na2WO4含量从0增加至3%时，LCST由41.6?C降低至34.4?C；复合水凝胶表现出双重pH响应性能，即在酸性条件下高度溶胀，中性条件下溶胀率减小，碱性条件下溶胀率又升高的现象。

Abstract:

A temperature and pH dual sensitive P(DEA-co-DMAEMA)/Na2WO4 hydrogel was synthesized by one pot method with N,N-diethylacrylamide (DEA) and dimethylaminoethyl methacrylate (DMAEMA) as monomers, N,N-methylene bisacrylamide (BIS) as a crosslinking agent, respectively. The effect of Na2WO4 on the structure, temperature and pH response of hydrogels was investigated. The results showed that there existed a physical cross-linking (hydrogen bonding and coordination) between Na2WO4 and polymers in addition to chemical cross-linking in composite hydrogel. Futhermore, the LCST of the composite hydrogel decreased linearly with the increasingof Na2WO4 content. When the Na2WO4 content increased from 0 to 3%, LCST decreased from 41.6?C to 34.4?C. Besides, the composite hydrogels exhibit double pH response properties: it highly swelled under acidic conditions, then the swelling ratio decreased under neutral conditions and increased again under alkaline condition.