Facilitated transport by hybrid POSS®–Matrimid®–Zn2+ nanocomposite membranes for the separation of natural gas

Hybrid POSS® Octa Amic Acid–Matrimid® nanocomposite membranes have been successfully fabricated. The study shows that the nano-sized POSS® could be distributed uniformly over the Matrimid® matrix with an intimate polymer–particle interface. This is presumably ascribed to the existence of intermolecular hydrogen bonding between the carboxylic groups of POSS® and Matrimid®. The excellent dispersion of POSS® with eight carboxylic functional groups each moiety provides a high-density ionic binding platform for the introduction of Zn2+, which is the engine of the facilitated transport to some specific gases. The best gas separation performance is observed for the hybrid POSS®–Matrimid®–Zn2+ nanocomposite membrane (20 wt% POSS®–Matrimid®–0.3 M ZnCl2), in which, the selectivity of CO2/CH4 and O2/N2 increases by 70% and 30%, respectively, when compared with untreated nanocomposite membrane (20 wt% POSS®–Matrimid®).