部分中和聚丙烯酸钠凝胶交联反应的动态流变分析

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中图分类号：R318.08 文献标志码：A

Abstract：Sixdiferent pharmaceutical excipients，partiallyneutralisedsodium polyacrylates，wereused to prepare hydrogels with aluminium glycolate，and the cros-linking reaction was investigated by rheological means.The dynamic rheological parameters of hydrogel cross-linking were studied over a period of 60d and the effects of molecular weight， degree of neutrality and pH values of partially neutralised sodium polyacrylate on the cross-linking process of the gels were discussed indetail.Theresultsshowed thatthecros-linkingreactionof the hydrogelsystemcouldbe divided intothree distinct phases：a fast reaction phase，a slow reaction phase anda termination phase.Non-linear least squares fiting of the kinetic curves of the partially neutralised sodium polyacrylate /Al3+ cross-linking reaction showed that the slow reaction phase was beterfitted bytheExp Asoc model， while the fastreaction phase was better fited bythe linear model. Whencomparing theeffectsofthesix partiallyneutralisedsodiumpolyacrylatesonthehydrogel properties，thehigherthe molecular weightof thesodium polyacrylate，the higherthemodulusofelasticityof thehydrogels.Conversely，alowerdegreeofneutrality resulted inshortergel formation times.Inadition，thereactionrateofhydrogels preparedfrompartiallyneutralisedsodium polyacrylates increased with higher pH values at the same degree of neutrality.

Key words： partialy neutralised sodium polyacrylate；hydrogel；crosslinking reaction；rheology；dynamics；model fitting

部分中和聚丙烯酸钠作为一类亲水性高分子材料[12]，其分子链中含有不同共聚比例的丙烯酸与丙烯酸钠，可通过大量羧基（—COOH）与交联剂中的金属离子发生配位交联[3.4]，形成具有三维网状结构的弹性水凝胶基质[5-8]。（剩余13291字）