AN IONICALLY CROSS-LINKABLE POLYPHOSPHAZENE - POLY[BIS(CARBOXYLATOPHENOXY)PHOSPHAZENE] AND ITS HYDROGELS AND MEMBRANES .8.
AN IONICALLY CROSS-LINKABLE POLYPHOSPHAZENE - POLY[BIS(CARBOXYLATOPHENOXY)PHOSPHAZENE] AND ITS HYDROGELS AND MEMBRANES .8.
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DOI：
10.1021/ma00191a015
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发表时间：
1989-01-01
期刊：
影响因子：
5.5
通讯作者：
KWON, S
中科院分区：
文献类型：
--
作者：
ALLCOCK, HR;KWON, S
六氯环三磷腈和聚二氯磷腈与对羟基苯甲酸乙酯的叔丁酯反应，得到了小分子环状的、高聚合度的、带有芳氧基酯侧基的磷腈。通过~（31）P NMR、NMR、红外光谱和热分析等手段对这两类化合物的结构和物理性质进行了研究。这些化合物与叔丁醇钾的反应引起酯基的完全水解，产生水介质可溶的、带有羧酸的环状和高度聚合的磷腈。当在水介质中用二价或三价阳离子的盐如氯化钙、溴化铜、硫酸铜或乙酸铝处理时，含羧酸的高聚物形成离子交联，从而产生水凝胶和膜。铝离子被证明是比二价阳离子更有效的交联剂。交联凝胶在中性或强酸性水介质中稳定，但在过量一价阳离子的碱性水溶液中交联过程被逆转。
Hexachlorocyclotriphosphazeneand poly (dichlorophosphazene) react with thesodium salt of ethyl p-hydroxybenzoate to give small molecule cyclic and high polymeric phosphazenes with aryloxy ester side groups. The structures and physical properties of both classes of compounds were investigated by 31P NMR, NMR, and infrared spectroscopies and by thermal analysis. Reaction of these compounds with potassium tert-butoxide brought about complete hydrolysis of the ester groups to yield aqueous media-soluble, carboxylic acid bearing cyclic and high polymeric phosphazenes. The carboxylic acid bearing highpolymer formed ionic cross-links when treated in aqueous media with salts of di-or trivalent cations, such as calcium chloride, copper bromide, copper sulfate, or aluminum acetate, toyield hydrogels and membranes. Aluminum ions proved to be more efficient cross-linking reagents than the divalent cations. The cross-linked gels were stable in neutral or strongly acidic aqueous media, but the cross-linking process was reversed in basic aqueous solutions of excess monovalent cations.