聚N-异丙基丙烯酰胺水凝胶的微波合成与性能

以水为溶剂,N-异丙基丙烯酰胺(NIPAM)为单体,N,N-亚甲基双丙烯酰胺(Bis)为交联剂,分别通过微波合成法和水浴加热法制备了聚N-异丙基丙烯酰胺(PNIPAM)水凝胶,研究了交联剂浓度、反应时间、反应温度等对反应的影响,及PNIPAM水凝胶在不同温度和pH值下的溶胀性变化。研究结果表明,与水浴加热法相比,微波合成法缩短了反应时间,从10h缩减至1h左右;适当延长反应时间和提升反应温度有利于提高单体转化率。微波法合成PNIPAM的最佳条件为:H2O为溶剂,100℃~110℃反应40 min~60 min,交联剂m(Bis)/m(NIPAM)=5/100,单体转化率97%~98%。而且,微波合成法制备的水凝胶具有更显著的温度和pH敏感性能。

Microwave Irradiation Synthesis of PNIPAM Hydrogels and Their Properties

Poly(N-isopropylacrylamide)(PNIPAM) hydrogels were separately synthesized by microwave irradiation and water-bath heating with water as media,using N,N-methylene-bisacylamide(Bis) as cross-linking agent.Influence of cross-linking agent,reaction temperature and reaction time on the yield was investigated.The temperature and pH sensitivity were tested respectively.The results show that microwave irradiation can greatly shorten reaction time from 10 hours to 1 hour in comparison with water-bath heating,and obviously improve the yield.Extending of reaction time and enhancing of reaction temperature are benefit to improve the yield.The optimum reaction conditions of microwave irradiation are as follows: water as solvent,reaction temperature 100 ℃～110 ℃,reaction time 40 min～60 min,m(Bis)/m(NIPAM)=5/100,97%～98% of the yields can be obtained. Microwave irradiation also improves the temperature-and pH-responsibility of the hydrogels.