(NIPAAm)类三元共聚及IPN水凝胶的合成与温敏性能的研究

Synthesis and thermo-sensitive of N-isoprooylacrylamid terpolymer & IPN hydrogels

采用自由基聚合法合成了P(AAm-co-NIPAAm-co-DMAA)三元共聚水凝胶和P(NIPAAm-co-AAm)/PDMAA互穿聚合物网络(IPN)水凝胶。研究了两种水凝胶的温敏及溶胀性能,并考察了DMAA含量对两种凝胶性能的影响。结果表明,P(AAm-co-NIPAAm-co-DMAA)三元共聚水凝胶和P(NIPAAm-co-AAm)/PDMAA互穿聚合物网络(IPN)水凝胶都具有热缩温敏性,DMAA的摩尔分数增加(7%～22%),两种水凝胶的LCST从40℃升高到45℃;三元共聚水凝胶平衡溶胀比(SR)由8.33提高至14.50,IPN水凝胶平衡溶胀比(SR)由5.61提高至11.66;两种水凝胶都能在30 min内达到消溶胀平衡,并且失水率在80%左右。IPN水凝胶的凝胶形态稳定性较三元共聚水凝胶明显提高。

P（AAm-co-NIPAAm-co-DMAA） terpolymer hydrogels and P（NIPAAm-co-AAm）/PDMAA IPN hydrogels have been prepared by free-radical polymerization. The thermo-sensitive and swelling behaviors have been studied by comparing the terpolymer with IPN hydrogels. And the influence of the amounts of DMAA on the properties of these hydrogels was investigated as well. The results indicated that P（AAm-co-NIPAAm-co- DMAA） terpolymer hydrogel and P（NIPAAm-co-AAm）/PDMAA IPN hydrogel showed negative-temperature sensitivity. With the amounts of DMAA＇s molar ratio increasing from 7 % to 22 %, the two kinds of hydrogels＇ LCST increased from 40 ℃ to 45 ＊（2, the terpolymer hydrogel＇ s SR increased from 8.33 to 14.50, and the IPN hydrogel＇ s SR increased from 5.61 to 11.66. These hydrogels reached shrinking balance within 30 min and their water loss rates are about 80%. The result showed the P（NIPAAm-co-AAm）/PDMAA IPN hydrogel＇ s gel form of stability was better than P（AAm-co-NIPAAm-co-DMAA） terpolymer hydrogel＇s.