Poly(ionic liquid) blended polyphenylene sulfone ultrafiltration membranes with enhanced surface hydrophilicity and antifouling performance

•Newly poly(ionic liquid) with hydrophilicity but insoluble in water was synthesized.•The construction of hydrogen bonds between poly(ionic liquid) and membrane matrix.•Improved hydrophilicity, reduced irreversible fouling and high flux recovery ratios of the blended membranes.•The modified membrane shows excellent anti-fouling properties towards BSA.•The modified membrane exhibits outstanding removal for dyes (EB and CR).