以羟丙基甲基纤维素的水溶液为反应介质制备了快速响应的温敏性聚(N-异丙基丙烯酰胺)(PNIPA)水凝胶。利用DSC对其相转变温度进行了表征,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...以羟丙基甲基纤维素的水溶液为反应介质制备了快速响应的温敏性聚(N-异丙基丙烯酰胺)(PNIPA)水凝胶。利用DSC对其相转变温度进行了表征,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。实验证明,与传统水凝胶相比,该水凝胶的溶胀性能有所提高,并且具有更快的响应速率。例如:该水凝胶在1 m in内失去89%的水,在4 m in内失去大约93%的水,而传统水凝胶在15 m in内仅失去66%左右的水。展开更多
The temperature dependence of the specific refractive index increment d n /d c of aqueous poly( N isopropylacrylamide) solution in the range of 20 ℃ to 35 ℃ were determined by a differential refractometer. The measu...The temperature dependence of the specific refractive index increment d n /d c of aqueous poly( N isopropylacrylamide) solution in the range of 20 ℃ to 35 ℃ were determined by a differential refractometer. The measured d n /d c of the solution decreases regularly and smoothly with increasing temperature until to the specific coil globule transition temperature of PNIPAM (around 32 ℃) and afterwards it increases with increasing temperature on the contrary. This extraordinary phenomenon is successfully explained and treated by a quantitative theory in terms of accompanying solvation desolvation process in the course of coil globule transition of the polymer chain in solution.展开更多
文摘以羟丙基甲基纤维素的水溶液为反应介质制备了快速响应的温敏性聚(N-异丙基丙烯酰胺)(PNIPA)水凝胶。利用DSC对其相转变温度进行了表征,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。实验证明,与传统水凝胶相比,该水凝胶的溶胀性能有所提高,并且具有更快的响应速率。例如:该水凝胶在1 m in内失去89%的水,在4 m in内失去大约93%的水,而传统水凝胶在15 m in内仅失去66%左右的水。
文摘The temperature dependence of the specific refractive index increment d n /d c of aqueous poly( N isopropylacrylamide) solution in the range of 20 ℃ to 35 ℃ were determined by a differential refractometer. The measured d n /d c of the solution decreases regularly and smoothly with increasing temperature until to the specific coil globule transition temperature of PNIPAM (around 32 ℃) and afterwards it increases with increasing temperature on the contrary. This extraordinary phenomenon is successfully explained and treated by a quantitative theory in terms of accompanying solvation desolvation process in the course of coil globule transition of the polymer chain in solution.
基金National Natural Science Foundation of China(51303158)Natural Science Foundation of Zhejiang Province(LQ12E03004)The Opening Foundation of Zhejiang Provincial Top Key Discipline(G9713101002)
