Effect of Extractant and Cold-drawing on the Structure and Performance of FIDPE Hollow Fiber Membranes Fabricated via Thermally Induced Phase Separation Method

Microporous polyolefin hollow fiber membranes were prepared from high density polyethylene （HDPE）-paraffin solution via thermally induced phase separation （TIPS） method. Effects of extraction and cold-drawing condition on membrane structure and performance were investigated.Five volatile solvents were used as extractant. Dimension of hollow fiber and gas permeation rate of membrane were measured. Mierostructure of membrane was examined by Scanning Electronic Microscope （SEM）. The results show that the membrane treated by pentane possesses a higher porosity, nitrogen permeability and lower shrinkage than those of membranes extracted by other three extractants. It is also found that the membrane stretched 133% shows the highest porosity and gas permeability in this study.     

Effect of Extractant and Cold-drawing on the Structure and Performance of HDPE Hollow Fiber Membranes Fabricated via Thermally Induced Phase Separation Method

IntroductionMicroporous membrane is widely used in filter ,oxygenator , contactor and battery separator . Traditionally ,polymer membranes shaped as porous hollow fibres , areprepared using the diffusion induced phase separationtechnique or DIPS[1].Inthis process ,a polymer solution ofa polymer and a solvent is contacted with a non-solvent forthe polymer . Because of initial interdiffusion of solventand nonsolvent ,the concentration in the polymer solutionchanges and, finally , phase separat…     

后处理对聚丙烯中空纤维膜性能的影响

采用熔融挤出拉伸法制备了聚丙烯中空纤维膜，详细探讨了中空纤维的机械性能，尤其是各种条件对其弹性恢复性能的影响，研究发现后处理(热处理条件和牵伸比)对膜材料的孔隙率，平均孔径和气体的穿透性能有很大的影响，采用片晶和微纤模型可以很好地解释中空纤维膜的实验现象和成孔机理。     

均粒白球的制备研究进展

均粒白球是一类应用很广泛的功能高分子材料,具有物理化学稳定性好、机械强度高、苯环反应活性高等优点,其功能化产品在诸多领域具有巨大的应用价值。本文综述了均粒白球的制备方法,包括喷射悬浮聚合法、多孔错流膜技术、孔板分散聚合技术,对在制备过程中影响液滴尺寸和白球粒径的因素进行了阐述和分析,并且总结了各方法的优缺点,最后对均粒白球的发展前景进行了展望。     

热致相分离法制备聚合物微孔材料

热致相分离是一种制备聚合物微孔材料的有效方法。本文介绍了聚合物初始浓度、聚合物分子量、稀释剂、冷却速率、萃取剂、聚合物密度等因素对热致相分离法制备聚合物微孔材料的影响,并对热致相分离法制备新型微孔材料的最新研究进展进行了综述。