Abstract: Poly(NIPAAm/X) copolymer hydrogels were synthesized by radiation polymerization at room temperature where X=acrylic acid (AAc), acrylamide (AAm), N-vinyl-4-pyrrolidone(N-vp) and 4-vinyl pyridine(4-vp). The optimum conditions of preparation were given. All the copolymer hydrogels possess temperature sensitivity and nice physical properties. Poly(NIPAAm/AAc) was the only copolymer hydrogel that not only had the temperature sensitivity but also had the pH sensitivity at pH=11, which had the swelling ratio as high as 350. Concentration effect of uranyl ions in dilute aqueous solution by the copolymer hydrogels synthesized here was investigated. It was found that only poly(NIPAAm/AAc) exhibited large concentration capacity for uranyl ions in weak acid solution. The concentration mechanism was discussed.

Key words: NIPAAm, copolymer hydrogels, radiation polymerization, concentration, environment sensitivity

摘要： 用γ辐射共聚方法制备了以NIPAAm为主要单体成分，分别含酸性单体AAc、中性单体N-vp、AAm和碱性单体4-vp 的共聚水凝胶，并给出了其最佳合成条件。产物性质测定表明它们均具温度敏感性和适宜的物理性能，其中poly(NIPAAm/AAc) 还具pH敏感性，在pH=11时最大溶胀比约为350倍。用上述共聚水凝胶对稀水溶液中UO₂²⁺离子进行浓集、分离的初探，结果表明只有poly(NIPAAm/AAc) 能有效浓集稀水溶液中的UO₂²⁺离子，并讨论了浓集条件和浓集机理。

关键词: 氮-异丙基丙烯酰胺, 丙烯酸酯, 乙烯基单体, 辐射聚合, 环境敏感性