Enhanced CO2 separation performance of P(PEGMA-co-DEAEMA-co-MMA) copolymer membrane through the synergistic effect of EO groups and amino groups

Abstract

We report a high performance and CO₂-philic, comb copolymer consisting of poly(ethylene glycol) methyl ether methacrylate (PEGMA), polymethyl methacrylate (PMMA) and poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) for use in composite membranes for CO₂/N₂ separation. Since the copolymers contain ethylene oxide (EO) groups and amino groups, the separation performance was expected to be enhanced by the synergistic effect of (1) the increased solubility of CO₂ by dipole–dipole interactions between CO₂ and EO units and (2) the enhanced CO₂ transport by reversible reactions between CO₂ and amino groups. The best separation performance was obtained from the PEDM5 composite membrane with 25 mol% of PEGMA, at which the CO₂ permeability was 308 barrer and CO₂/N₂ selectivity was 38, which displays a potentially promising alternative for CO₂ separation from N₂.