Crosslinkable polyaryletherketone ultrafiltration membranes with solvent-resistant improvement

We demonstrate the successful synthesis of a novel crosslinkable polyaryletherketone, SCBI-PAEK-6F, which has pendant benzimidazole groups as a tunable content. With the strategic incorporation of benzimidazole groups, the SCBI-PAEK-6F membranes prepared by non-solvent induced phase separation (NIPS) method became cross-linkable. Then the solvent-resistance of ultrafiltration membranes was improved through cross-linking. The structures and performances of the membranes, along with the effects of the post cross-linking, had been systematically investigated. The solvent-resistance test confirmed that the membrane stability in representative polar aprotic solvents had been pronouncedly enhanced after cross-linking. Cross-linked membranes had high gel contents of about 80% after soaking in the solvents for 7 days. Pore size and porosity analysis had shown that the mean pore size and porosity of SCBI-PAEK-6F membranes became larger after the cross-linking process. Meanwhile, the cross-linked membranes showed the improved ultrafiltration performance, the cross-linked membranes had pure water flux which is 50% bigger than the pristine membranes. In addition, all membranes showed superior bovine serum albumin rejection (over 98%), but the antifouling property of membranes became a little worse after the cross-linking process.