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采用预辐射接枝法，将Ｎ－异丙基丙烯酰胺（ＮＩＰＡＡｍ）接枝到乙烯－醋酸乙烯酯共聚物（ＥＶＡ）试片上。研究了各种因素对接枝反应的影响。结果表明，接枝体系具有一般预辐照液－固两相接枝体系的共性，如在接枝反应前期，反应速度不变，以后逐渐下降，接枝率与反应温度成正比，少量的Ｃｕ（ＮＯ３）２，就能使接枝率急剧下降。经ＮＩＰＡＡｍ接枝的ＥＶＡ表面，呈现与ＮＩＰＡＡｍ凝胶相似的热敏性，即在低于“较低临界溶解温度”（ＬＣＳＴ）的温度时溶胀于水，而在高于ＬＣＳＴ时，迅速退溶胀，其ＬＣＳＴ约为３２℃，水含量随温度的变化是可逆的。相比之下，接枝ＮＩＰＡＡｍ的ＥＶＡ表面比ＮＩＰＡＡｍ凝胶具有更灵敏的热敏性。试片的ＬＣＳＴ会随着接枝层的组成变化而漂移。
N-isopropylacrylamide (NIPAAm) was grafted to the ethylene-vinyl acetate copolymer (EVA) test specimen by a pre-irradiation grafting method. The effects of various factors on the grafting reaction were studied. The results showed that the grafting system has the common pre-irradiation liquid-solid two-phase grafting system common, such as in the early grafting reaction, the reaction rate unchanged, and then gradually decreased, grafting rate and the reaction temperature is proportional to a small amount of Cu (NO3) 2, can make the grafting rate dropped sharply. The NIPAAm-grafted EVA surface exhibits a similar thermal sensitivity to the NIPAAm gel that swelled in water below the lower critical solution temperature (LCST) and swelled rapidly above LCST, which The LCST is about 32 ° C and the change in water content with temperature is reversible. In contrast, the EVA surface grafted with NIPAAm possessed more sensitive heat sensitivity than the NIPAAm gel. The LCST of the test strip will drift as the composition of the grafted layer changes.