PNIPAM/蒙脱土复合水凝胶辐射合成与表征

Radiation synthesis of PNIPAM/montmorillonite composite hydrogels

采用辐射聚合方法合成了PNIPAM/蒙脱土(MMT)复合水凝胶;研究了蒙脱土对PNIPAM/MMT复合水凝胶溶胀性能和压缩性能的影响。结果表明,虽然MMT能提高复合水凝胶的初始溶胀速率和平衡溶胀率,但它不改变凝胶原有的环境响应性能和溶胀机理。PNIPAM水凝胶和PNIPAM/MMT复合水凝胶均具有温度敏感性,低临界溶解温度(LCST)均在32℃左右,溶胀机理均遵循Fickian扩散模式,即水分子的扩散成为水凝胶溶胀的决定过程。使用MMT能改善PNIPAM/MMT复合水凝胶的压缩性能;且复合水凝胶的压缩性能随MMT含量的增加而提高。

PNIPAM/montmorillonite（MMT） composite hydrogels were synthesized by radiation polymerization. Effects of the MMT on swelling and compressive properties of the hydrogels were investigated. The results showed that MMT could increase early swelling rate and balanced swelling rate of the composite hydrogel, but it did not change intrinsic environmental response performance and swelling mechanism of the hydrogel. The PNIPAM and PNIPAM/MMT hydrogels are of the same temperature sensitivity. The lower critical solution temperature （LCST） is about 32℃ and the swelling mechanism also follows Fickian diffusion model, i.e diffusion of water molecule determines the swelling of hydrogels. Compression performance of the PNIPAM/MMT composite hydrogels was improved with the use of MMT and compression performance of composite hydrogels took on the upward trend with the increase of MMT content.