A novel stimuli-responsive and fouling resistant PVDF ultrafiltration membrane prepared by using amphiphilic copolymer of poly(vinylidene fluoride) and Poly(2-N-morpholino)ethyl methacrylate

Abstract

A novel stimuli-responsive and anti fouling poly(vinylidene fluoride) (PVDF) membrane is proposed by incorporating amphiphilic copolymer, poly(vinylidene fluoride)-graft-Poly(2-N-morpholino)ethyl methacrylate (PVDF-g-PMEMA) as modifier due to presence of tertiary amine and heterocyclic oxygen (oxa-group). The prepared membrane exhibits dual responsive properties, i.e. pH responsive and temperature responsive behaviour as well as antifouling characteristics. The mechanism of the pH-responsive performance is originated from the pH-responsive swelling and shrinking of PMEMA chains embedded in the membrane and Temperature-responsive performance is attributed to the Temperature-responsive extended and collapsed state of PMEMA chains at around LCST. The antifouling property is induced owing to presence of hydrophilic PMEMA chains in the membrane. As a result, the permeability of the novel PVDF membrane was increased from 0.29 L/m2hkPa (plain membrane) to 0.77 L/m2hkPa (modified membrane) with addition of amphiphilic copolymer from 0 wt % to 3 wt %. The maximum o/w emulsion rejection percentage of about 97% was obtained through blended membrane. Thus the proposed membrane in this research work offers an approach for the treatment of oily wastewater.