采用熔融纺丝制得改性聚氨酯系中空纤维膜,通过测试水通量随压力的变化研究了拉伸、热处理温度和热处理时间对改性聚氨酯系中空纤维膜压力响应行为的影响.结果表明,所得膜可发生明显的压力响应行为,且拉伸倍数越大,膜的强度越大,压力响应行为越精确；随热处理温度升高,膜的支撑性变差,压力响应行为变弱；随热处理时间延长,膜形变回复率变低,压力响应行为减弱.%Modified polyurethane (PU) based hollow fiber membranes were prepared by the melt-spinning method. Influences of drawing, heat-treatment temperature and heat-treatment time on the pressure-responsive behavior were studied by the relationships between water flux and test pressure. The results showed that the hollow fiber membranes exhibited obvious pressure-responsive behavior. With increasing theoretical draw ratio, the strength of the membrane was greater and the pressure-responsive behavior was stronger. While, membrane pore size on inner surface and mean pore size became larger, the pure water flux (PWF) increased, the porosity first increased then slightly decreased. With increasing heat-treatment temperature, membrane support became worse and the pressure-responsive behavior became weaker. While, membrane pore size became smaller, the PWF and porosity of membrane increased and then decreased. With extending heat-treatment times, the deformation-recovery ratio of membrane diminished and the pressure-responsive behavior became weaker. The PWF and porosity of membrane first increased, then decreased, finally achieved stability.
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