快速响应的温敏性聚(N-异丙基丙烯酰胺)水凝胶的制备及表征

Synthesis and Characterization of Thermo-sensitive Poly(N-isopropylacrylamide) Hydrogels with Fast Response Rate

以不同浓度的β-环糊精水溶液为反应介质制备了一系列快速响应的温度敏感性聚(N-异丙基丙烯酰胺)水凝胶。利用SEM观察其表面形态,并测定了不同温度下达到平衡时水凝胶的溶胀比,研究了水凝胶的去溶胀动力学。结果表明,与传统水凝胶相比,该水凝胶的溶胀性能略有提高,并且对温度的变化具有非常快的响应速率。以0·25(wt)%的β-环糊精水溶液中制备的水凝胶为例,该水凝胶仅1min内就失去约94%的水,而传统水凝胶在15min内仅失去66%左右的水。

Tbermo-sensitive poly （N-isopropylacrylamide） （PNIPA） hydrogel was prepared in β-eyclodextrin aqueous solutions with different concentrations. The surface morphology of PNIPA hydrogel was observed using a scanning electron microscope. The swelling ratios of the hydrogel at different temperatures were measured. Further-more, the deswelling kinetics of the hydrogel was also studied through measuring their water retention. In comparison with a conventional PNIPA hydrogel prepared in water, the hydrogel obtained in β-eyelo-dextrin aqueous solutions had higher swelling ratios at temperatures below the lower critical solution temperature and exhibited much faster response rate to temperature change.