화학공학소재연구정보센터
Journal of Colloid and Interface Science, Vol.490, 29-36, 2017
Mixed-matrix membranes incorporated with porous shape-persistent organic cages for gas separation
There has been much recent interest in the use of porous materials derived from self-assembling, shape persistent organic cages due to their solubility and easy post-synthetic modification. Herein we report the preparation of novel mixed-matrix membranes (MMMs) employing the porous organic cage Noria and its derivatives Noria-Boc and Noria-(COBu)-Bu-t as the fillers, and a fluorine containing polyimide, 6FDA-DAM, as the polymeric matrix. The physical structures and properties of Noria and its derivatives were measured and investigated. Noria with substituents of Boc (cleaved by thermal treatment during the process of membrane fabrication) and (COBu)-Bu-t groups tend to show much better compatibility with polyimide than Noria itself, resulting in homogeneous dispersion of nanoaggregates and fine adhesion between the two phases in the derived Noria/6FDA-DAM and Noria-CO(t)Bui/FDA-DAM MMMs. Gas permeation tests revealed that Noria and Noria-Cniu nanoparticles have different effect on gas separation performance of MMMs. The introduction of Noria into 6FDA-DAM tends to enhance CO2/CH4 selectivity and thus improve its gas separation properties, though a decrease in the observed permeability could be observed. In contrast, the introduction of Noria-(COBu)-Bu-t with higher surface area and larger pores tends to increase the free volume and gas permeability of MMMs. These results show that both the morphology and the gas separation properties of MMMs could be tuned by tailoring the structures of porous organic cages. (C) 2016 Elsevier Inc. All rights reserved.