Free-standing thermosensitive composite gel particles incorporating ionic liquids

在本研究中，为了开发具有离子液体（IL）热敏特性而不分散在IL中的独立凝胶颗粒，在PPhEMA/IL凝胶颗粒存在下，通过MMA的种子聚合制备了2-苯乙基甲基丙烯酸酯聚合物（PPhEMA）和聚甲基丙烯酸甲酯（PMMA）组成的复合凝胶颗粒。其中，PPhEMA在IL中表现出较低的临界溶液温度（LCST）型相变行为。PPhEMA相表现出LCST型体积相变行为，IL的分离发生在LCST以上。PMMA相肿胀，IL从PPhEMA相分离。有趣的是，复合凝胶颗粒在空气和真空中都表现出相似的体积-相转变行为，而凝胶颗粒中的IL没有泄漏，这应该是独立的热敏凝胶颗粒。

In this study, to develop free-standing gel particles that exhibit the thermosensitive properties of the incorporated ionic liquid (IL) without being dispersed in the IL, composite gel particles consisting of 2-phenylethyl methacrylate polymer (PPhEMA) and poly(methyl methacrylate) (PMMA) were prepared by seeded polymerization of MMA in the presence of PPhEMA/IL gel particles, in which PPhEMA exhibited lower critical solution temperature (LCST)-type phase transition behavior in IL. The PPhEMA phase exhibited LCST-type volume-phase transition behavior and separation of IL occurred above the LCST. In contrast, the PMMA phase was swollen with IL separated from the PPhEMA phase. Interestingly, the composite gel particles exhibited similar volume-phase transition behavior in both air and vacuum without leaking of IL from gel particles, which should be free-standing thermosensitive gel particles.