定量研究环糊精聚合物包合作用的新方法

摘要

通过聚合物接枝改性的方法制备了β-环糊精改性聚丙烯酸（PAAβCDen）和丹磺酰基团改性聚丙烯酸（PAADSen）,并用二维氢核磁、流变学、紫外-可见分光光度法等方法对接枝于聚合物上的环糊精主客体相互作用进行了定量研究。结果表明：接枝于聚丙烯酸链上的β-环糊精和丹磺酰基团之间能够形成主客体包合结构,从而使PAAβCDen和PAADSen之间产生交联,并且首次采用紫外-可见分光光度法测得接枝于不同聚合物链上环糊精基团和丹磺酰基团之间的结合常数为（27.5±3）L/mol,远小于自由状态下β-环糊精与丹酰胺之间的结合常数（（103±5）L/mol）。%Both β-cyclodextrin（PAAβCDen） and dansyl modified poly（acrylic acid）s（PAADSen） were synthesized respectively by polymer grafting reaction.The inclusive association between PAAβCDen and PAADSen was studied quantitatively by 2D 1H-NMR,rheology and UV-Vis spectroscopy.The results showed that the crosslinking between PAAβCDen and PAADSen was formed by host-guest interaction between β-cyclodextrin and dansyl substituents.The association constant between β-cyclodextrin and dansyl substituents in PAA was determined as（27.5±3） L/mol for the first time,which was much smaller than that of free β-cyclodextrin with dansyl amide（（103±5） L/mol）.