Hybrid brominated sulfonated poly(2,6-diphenyl-1,4-phenylene oxide) and SiO2 nanocomposite membranes for CO2/N2 separation

Brominated sulfonated poly(2,6-diphenyl-1,4-phenylene oxide) (BSPPOdp) was synthesized as a new membrane material for CO2/N-2 separation. The 90% brominated-10% sulfonated PPOdp (BSPPO(dp)9010) was selected as representative material for membrane preparation. It formed flexible membranes with higher CO2 permeability (P-CO2 = 58 Barrer) and selectivity (alpha(CO2/N2) = 36) than poly(2,6-dimethyl-1,4-phenylene oxide) (PPOdm) membranes. BSPPO(dp)9010 membranes containing silica nanoparticles enhanced CO2 permeability while maintaining the CO2/N-2 selectivity as compared with the pure BSPPO(dp)9010 membranes. The CO2 permeability increased as a function of the silica content in the membrane. The separation mechanism for CO2/N-2 in the membranes was attributed to the gas solubility effect rather than the gas diffusivity. (c) 2012 Chinese Materials Research Society. Production and hosting by Elsevier Ltd. All rights reserved.