【摘要】 在不使用交联剂的情况下,采用无皂乳液聚合法合成自交联聚(N-异丙基丙烯酰胺)(PNIPAM)水凝胶微球。固体13C NMR分析结果表明,PNIPAM水凝胶微球中存在因链转移反应形成的自交联点。自交联PNIPAM水凝胶微球的相转变温度范围很窄,接近非连续体积相转变行为。合成过程中反应温度、反应时间、引发剂用量对微球粒径和溶胀比有比较明显的影响,这些因素对微球的相转变温度及其范围的影响均很小。更多还原

【Abstract】 The poly(N-isopropylacrylamide) (PNIPAM) hydrogel microspheres were synthesized by SFEP without crosslinker. The comparative analysis of solid 13C NMR spectra of linear PNIPAM and the self-crosslinked PNIPAM microspheres indicated that there are self-crosslinking points formed by chain transfer reaction in the microspheres. The phase transition temperature range of the self-crosslinked PNIPAM hydrogel microspheres was very narrow, and they had nearly noncontinuous phase transition behavior. The particle size and swelling ratio of the PNIPAM microspheres were more influenced by the reaction temperature, reaction time, and the amount of initiator used, while their phase transition temperature range was less effected by these factors.更多还原