刚性基团桥接聚硅氧烷/乙基纤维素混合膜的制备及其CO_(2)的分离

Preparation of rigid-group-bridged polysiloxanes/ethylcellulose mixed membranes for CO_(2) separation

以3种含刚性基团(六氟酰亚胺、萘基酰亚胺和芴)桥接聚硅氧烷(6FBPMS、NTBPMS和BAFBPMS)为改性剂,乙基纤维素(EC)为基质,通过溶液共混、涂敷法制备了3类不同负载量桥接聚硅氧烷的改性EC混合膜(6FBPMS/EC、NTBPMS/EC和BAFBPMS/EC)。3类复合膜具有良好的成膜性,且显示出高的力学性能和热稳定性。测试了混合膜对体积比都为1∶1的混合气体对CO_(2)/N_(2)和CO_(2)/CH4的透过选择性。结果表明,相较于纯EC膜,3类膜在保持选择性的同时,显示出更高的CO_(2)透过性;特别是NTBPMS/EC混合膜,其对CO_(2)透过性达到213 barrer以上,是纯EC的4.9倍。

Three types of rigid-group-bridged polysiloxanes-modified ethylcellulose(EC)mixed membranes were prepared by using three bridged-polysiloxanes with different rigid groups of hexafluoroimide,naphthalimide,and fluorene as modifiers and EC as a substrate,through solution co-blending and coating.The three mixed membranes exhibited a good film formation ability,high mechanical properties,and good thermal stability.Compared to pure EC membrane,the three mixed membranes gained an improvement in the permeability of CO_(2) without sacrificing selectivity(CO_(2)/N_(2) and CO_(2)/CH_(4)).Especially,the naphthalimide bridged-polysiloxanes obtained a CO_(2) permeation coefficient of over 213 barrers,which is 4.9 times higher than pure EC membrane.