Facile fabrication of 6FDA-DAM/PGMA blend membranes for advanced gas separation

Polymer blend membranes are an efficient and cost-effective route to improve the gas separation performance. The poor solubility and compatibility of the polymer are the main challenge to overcome in blend membranes procedures. Here, the incorporation of electron beam (EB) irradiation-induced polymer to membranes were reported to successfully avoid the poor solubility and compatibility between polymer. Specifically, small molecule glycidyl methacrylate (GMA) is dispersed into 6FDA-DAM membrane, 6FDA-DAM/PGMA blend membranes are obtained via EB-irradiation-polymerized GMA to form PGMA and deposit in DAM membrane in-situ. The loads of PGMA in 6FDA-DAM membrane (7.3 %-30.5 %) were controlled by EB-irradiation dosagess (from 60 kGy to 120 kGy). The resulted 6FDA-DAM/PGMA-x blend membranes showed a strong molecular sieve, such as the CO₂/CH₄ and H₂/CH₄ selectivity of 6FDA-DAM/PGMA-21.7 % membranes are improved by 352 % and 662 % compared with 6FDA-DAM, which exceed 2008 and 2015 upper bound. The enhanced performance results from incorporation of PGMA to form sub-nanometre-sized channel in 6FDA-DAM membrane. This work provides a facile and universal strategy to induce small molecule polymerization and in-situ incorporate to the membrane via EB-irradiation technology for gas separation.