以聚丙烯腈(RAN)为前驱体采用浸渍涂膜法在煤基炭管支撑体上制备出聚丙烯腈炭-炭复合膜,考察了涂膜液浓度,浸涂和干燥条件以及涂膜次数对聚丙烯腈炭-炭复合膜性能的影响.结果表明,涂膜液浓度、干燥条件以及涂膜次数对炭-炭复合膜性能的影响显著.随着涂膜液浓度的增大,炭-炭复合膜的平均孔径和气体通量均呈现先减后增的趋势.升高干燥温度和延长干燥时间,使炭-炭复合膜平均孔径减小,但当达到一定程度时变化不明显.增加涂膜次数使炭-炭复合膜平均孔径减小,但过多的涂膜次数会使膜层在炭化后产生裂纹和剥落现象.通过调整实验参数制备出了复合效果较好,表面光滑无缺陷的聚丙烯腈炭-炭复合膜.
PAN- based C - C composite membrane was prepared using dip - coating method and pyrolysis of polyacrylonitrile (PAN) on tublar carbon support derived from coal. The effects of PAN concentration of in coating solution, dip- coating parameters(soaking time and Elevating rate), drying parameters(drying time and temperature) and coating numbers on the properties of PAN - based C- C composite membrane were investigate. The results indicate that the performance of PAN - based C- C composite membrane mainly depends on PAN concentration solution, drying parameters and coating numbers, although all experimental parameters may have a certain influence. With the increase in PAN concentration in coating solution, the average pore diameter and gas flux decrease first, and then increase. The increase in drying time and temperature give rise to the decrease of average pore diameter, however, the variations are not obvious when they reach a critical values. The increase in coating numbers can decrease the average pore diameter, however, too much coating number can result in crack. Thus a large, crack - free PAN - based C - C composite membrane can be prepared by optimizing the exoerimental parameters.