摘要
炭膜是由有机聚合物经高温热解炭化制备而成的一种新型炭基膜材料.从炭膜前驱体的化学结构设计出发,选择开发和自主合成了2种新型的刚性、高自由体积的聚合物-含有Cardo侧基的酚酞型聚芳醚酮(PEK-C)和含芴基共聚聚酰亚胺(BAF:BAHF(1:1)-6FDA),经过高温热解炭化制得炭膜.两种炭膜对小分子气体都具有较高的气体渗透性能,其中CO_2的渗透系数分别最高可达8 111 Barrer和24 770 Barrer(1 Barrer=1×10~(-10)cm~3(STP)cm/cm~2 s cmHg),对CO_2/CH_4、CO_2/N_2和O_2/N_2混合气体的分离性能远超过聚合物膜的Robeson上限,在天然气的提纯、空气的分离和冶金工业用气体的处理等方面具有很大工业化应用的潜力.
Carbon membrane is the novel porous carbon-based membrane material,which prepared by the pyrolysis of the polymeric precursors.In this paper,two novel polymers of high rigidity and high free volume were developed and synthesized for the preparation of carbon membranes,including phenolphthalein-based poly(arylene ether ketone)(PEK-C) with cardo groups and copolyimide(BAF:BAHF(1:1)-6FDA) with fluorenyl groups.Carbon membranes prepared by two types of polymeric precursors show high gas permeability for small-molecule gases,especially for CO_2 which was up to 8 111 Barrer and 24 770 Barrer(1 Barrer =1×10~(-10) cm~3(STP) cm/cm~2 s cmHg),respectively.Moreover,the gas separation properties of these carbon membranes for mixed gases of CO_2/CH_4,CO_2/N_2 and O_2/N_2surpassed Robeson upper bound of polymer membranes,which possess great potential for industrial application such as purification of natural gases,air separation,processing of metallurgical industrial gases.
引文
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