温度和pH敏感性互穿聚合物网络水凝胶的合成与性能研究

Synthesis and Characterization of Interpenetrating Polymer Network(IPN) Hydrogels with Temperature and pH Sensibility

以N,N-亚甲基双丙烯酰胺(MBA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,在无氧及60℃恒温条件下,由丙烯酸(AA)、甲基丙烯酸β-羟基乙酯(HEMA)和N-乙烯基吡咯烷酮(NVP)合成了具有温度及pH双重敏感性的P(NVP-co-HEMA)/PAA和P(NVP-co-AA)/PHEMA互穿聚合物网络(IPN)水凝胶。制备的这2种水凝胶经4 h的溶胀均能达到平衡状态,且在pH值为1.40和9.l8的缓冲溶液中分别呈现出“热缩型”和“热胀型”的温敏行为。此外,由于AA的离解,使水凝胶在弱碱环境中的溶胀率(SR>20)远大于在酸性环境中的溶胀率(SR<7)。

P(NVP - co - HEMA)/PAA and P(NVP - co - AA)/PHEMA intetpenetrating polymer network(IPN) hydrogels with temperature and pH sensibility were synthesized from acrylic acid (AA), 2 - hydroxyethyl methacrylate(HEMA), and N - vinylpyrrolidone(NVP) using N , N - methylenebisacrylamide as crosslinker and AIBN as initiator under the condition of oxygen - absence and 60℃. The experimental results revealed that the hydrogels could reach their equilibrium state after swelled for 4 h. The swelling ratio (SR) of the two hydrogels would decrease in acidic solution(pH = 1.40) and increase in weak alkaline solution(pH = 9.18) while the temperature raised. As the result of ionization of AA, the SR of hydrogels in weak alkaline solution( SR > 20) was much more than that in acidic solution( SR < 7) .