本文采用粘度法测定了聚偏氟乙烯(PVDF)/N,N-二甲基乙酰胺(DMAc)/一缩二乙二醇(DEG)体系的凝胶分相温度,考察了粘度计转子的转速、高分子浓度、溶液的邻近比及熟化时间对溶液凝胶分相温度的影响.结果显示高分子溶液凝胶分相温度与粘度计转子的转速无关,但随着高分子浓度、溶液的邻近比及熟化时间的增加而升高.粘度法来确定PVDF溶液的凝胶分相温度是一种简单、准确地确定铸膜液状态的方法.

The gelation temperature of PVDF/DMAc/DEG ternary solution was determined by viscosity measurement. The effect of the shear rate, PVDF concentration, approaching value and aging time were investigated. Results indicated that the gelation temperature is not related to the shear rate, however increases with PVDF concentration, approaching value and aging time. The new method in determination of gelation temperature is simple, accurate for investigating polymer solution thermodynamic

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