Improved performance of the ultrafiltration membranes by simple modification with air plasma treatment and polymeric deposition

This study seeks to increase the antifouling properties of fluorinated polyvinylidene (PVDF) membranes through the synergistic application of plasma treatment and polymer deposition, employing polymerizations of polyvinylpyrrolidone (PVP) and polyethyleneimine (PEI). The results show remarkable success in modifications, presenting exceptional performance. Two distinct surface modification methods, plasma treatment and polymer deposition, were used to improve the antifouling properties and filtration performance of PVDF membranes. The plasma used was a discharge dielectric barrier using ambient air as gas, and hydrophilic polymers, PVP, and PEI. The results outlined changes in membrane roughness with a significant roughness reduction of up to 43% evident based on topographic and morphological analyses. Hydraulic permeability analysis revealed a substantial 35-fold increase, indicating a notable improvement in performance. All treated membranes exhibited higher water affinity and superior performance during 12-h ultrafiltration compared to their untreated counterparts. After chemical cleaning, water flux recovery exceeded 85% for all treated membranes, indicating the inherent antifouling properties of the surface. Air plasma treatment and polymer deposition change the roughness of PVDF membranes, leading to higher ultrafiltration performance. image