快速响应大孔聚(N-异丙基丙烯酰胺-co-丙烯酸)水凝胶的合成及表征

以聚乙二醇6000为成孔剂,由自由基引发N-异丙基丙烯酰胺(NIPA)和丙烯酸(AAc)共聚交联得到大孔凝胶,研究了凝胶对环境温度的响应性能.在凝胶制备过程中,PEG6000分子充当成孔剂,得到的凝胶具有大孔结构.这种大孔结构有利于水分子的进出,大孔凝胶对温度变化有较快的响应速率.增加亲水单体AAc的含量,凝胶的LCST有所升高,凝胶的亲水性增强,在较低温度下凝胶的溶胀率也随之升高.振荡实验表明,所得的大孔凝胶具有反复使用的能力.

Preparation and Characterization of Fast-responsive Porous Poly(N-isopropylacrylamide-co-acrylic Acid) Hydrogels

Temperature-sensitive porous poly(N-isopropylacrylamide-co-acrylic acid)P(NIPA-co-AAc)] hydrogels with fast responsive properties were prepared by radical copolymerization in aqueous solution via using PEG6000 as the pore-forming agent. In comparison to the conventional gels, the porous P(NIPA-co-AAc) gels exhibited faster response rate to temperature changes and higher swelling ratios at the temperature below lower critical solution temperature(LCST), which can be attributed to the porous structure formed in the process of the polymerization/crosslinking. With increasing the contents of AAc in the gel matrixs, the LCST increased, which was caused by the high hydrophilicity of AAC component. The results suggest the potential of these novel porous hydrogels for the controlled release of drugs, especially for macromolecular drugs.