Preparation and characterization of a PVDF/EG-POSS hybrid ultrafiltration membrane for anti-fouling improvement

Abstract

Octa vinyl silsesquioxane (OvPOSS) was used to synthesis POSS grafted ethylene glycol (EG) (EG-POSS). EG-POSS was synthesized by a two-step route. OvPOSS was first oxidized to prepare Epoxy-POSS. EG was used to graft Epoxy-POSS to obtain EG-POSS by ring opening reaction of epoxy groups. A polyvinylidene fluoride (PVDF)/EG-POSS hybrid membrane was prepared by a phase separation process. POSS was characterized by FTIR, NMR and TEM. The hybrid membranes were characterized by pure water flux, retention ratio to BSA, contact angle, BSA adsorption capacity, mechanical properties, XRD, SEM and AFM. The hydrophilicity and anitifouling properties of the pure PVDF membrane were improved by incorporating EG-POSS. The pure water flux of the hybrid membrane reached a maximum when 0.5% EG-POSS was added in the casting solution. The addition of EG-POSS had a positive effect on the mechanical properties of the PVDF membrane.