【摘要】 通过溶胶-凝胶法制备出系列聚酰亚胺PI(HQDPA-DMMDA)/TiO2纳米复合气体分离膜。采用TEM、WAXD和DSC等手段测试了复合膜的某些物理特性;研究了复合膜对H2、N2、O2、CO2和CH4等五种气体的透气性能及其与温度的关系,并对复合膜的结构与透气性能的关系作了推测。结果表明,TiO2的引入并未明显改变PI的分子链间距。随着PI中TiO2含量的增加,复合膜的透气系数开始逐渐增加,当TiO2含量为22.3%时,则显著增加,且仍保持很高的分离系数。提出用无机纳米网络促进传输作用来解释复合膜的透气机理。更多还原

【Abstract】 Nano-composite membranes based on a polyimide（HQDPA-DMMDA） and TiO₂ sol were fabricated by the sol-gel process. The physical properties were characterized by TEM, WAXD, and DSC. Permeability data for gases such as H₂, N₂, O₂, CO₂ and CH₄ were collected as a function of TiO₂ content and temperature. The results show that the solvent resistance property and the glass transition temperature of the composite is enhanced markedly with TiO₂ content increasing. The permeability of H₂, N₂, O₂, CO₂ and CH₄ of composite membrane with TiO₂ content of （22.3%） are （3.7）, （3.3）, （4.3）, （4.4） and （5.5） times as much as those of pure polyimide at 298 K. With PH₂=（14.1） Barrer, α_H2/N2 =（187.5） and α_H2/CH4=（143.2）, the nano-composite membrane is a desirable gas separation membrane material for H₂ recovery. A mechanism of nano-framework facilitated transport was proposed to explain the results.更多还原