【摘要】 研究了甲基丙烯酸十二烷或丁酯、甲基丙烯酰胺及丙烯酸与 4 ,4′ 二 (甲基丙烯酰胺基 )偶氮苯交联共聚凝胶的消溶胀动力学 .这类凝胶在pH7 4或pH8 0的缓冲溶液中达到溶胀平衡后 ,将其分别转入pH2 2和pH4 0的缓冲溶液中 .凝胶的消溶胀过程表现出两种情况 :一种是凝胶直接发生消溶胀 ,另一种是凝胶首先经历一个短时的溶胀然后再发生消溶胀 ,呈明显不同的两种消溶胀机制 .前者在单位时间内释水量 [(Ht-H0 ) t]的倒数与消溶胀时间有一个良好的线性相关性 ;而后者在单位时间内含水量 [Ht t]平方根的倒数与消溶胀时间有一个良好的线性相关性 .更多还原

【Abstract】 Hydrogels based on n alkyl methacrylate esters( n AMA),acrylic acid and acrylamide cross linked with 4,4′ di(methacryloylmino)azobenzene were preparared,and their deswelling kinetics was studied.The hydrogels swellon at pH values of 7 4 and 8 0 were transferred into buffered solutions at pH2 2 and pH4 0 respectively.The processes of deswelling appear in both cases:The first is that hydrogels deswelled immediately after the immersion of the swollen hydrogels into the lower pH of buffered solutions;the other is that hydrogels proceeded a short time swelling before deswelling.For the former the reciprocal of the average rate of deswelling [ t/(H t -H 0) ] has an excellent linear correlation with the time of deswelling.For latter the reciprocal of square root of water uptake in unit time [ (t/H t ) 1/2 ] has an excellent linear correlation with the time of deswelling.更多还原