论文部分内容阅读
采用溶胶凝胶法,在以TiO2为过渡层的硅藻土-莫来石陶瓷膜管基底上,制备了组分不同的聚酰亚胺/SiO2杂化膜。聚酰亚胺是利用4,4′-六氟亚异丙基邻苯二甲酸酐、2,4,6-三甲基-1,3-苯二胺和3,5-二氨基苯甲酸在溶液中进行亚胺化完成的。采用FT-IR、TG/DTA、DSC、SEM、BET和气体渗透测定对膜进行了表征和测试。结果表明,聚酰亚胺通过支链上的羧酸基和SiO2相键连织构成了具有规则孔道的空间网状结构,并且随着SiO2含量的增加孔径逐渐减小;杂化膜具有较高的热稳定性和有机无机兼容性;相对于聚酰亚胺膜,杂化膜对H2、CO2和H2O与N2相比较具有较高的分离性,SiO2含量为25(wt)%的杂化膜对H2/N2、CO2/N2和H2O/N2的分离因子分别达到55.9、31.1和42.8。
Sol-gel method was used to fabricate polyimide / SiO2 hybrid films with different composition on a diatomite-mullite ceramic tube substrate with TiO2 as the transition layer. Polyimide is prepared using 4,4’-hexafluoroisopropylidene phthalic anhydride, 2,4,6-trimethyl-1,3-phenylenediamine and 3,5-diaminobenzoic acid The solution is imidized. The membranes were characterized and tested using FT-IR, TG / DTA, DSC, SEM, BET and gas permeation assays. The results showed that the polyimides formed a spatial network structure with regular pores through the carboxylic acid groups and the SiO2 phase bonds on the branches, and the pore diameters decreased gradually with the increase of SiO2 content. The hybrid membranes had higher Thermal stability and organic-inorganic compatibility. Compared with polyimide films, the hybrid films have higher separability for H2, CO2 and H2O compared with N2 and hybrid films with SiO2 content of 25% by weight The separation factors for H2 / N2, CO2 / N2 and H2O / N2 were 55.9, 31.1 and 42.8, respectively.