Journal of Membrane Science, Vol.481, 137-147, 2015
Stimuli responsive and low fouling ultrafiltration membranes from blends of polyvinylidene fluoride and designed library of amphiphilic poly(methyl methacrylate) containing copolymers
Amphiphilic copolymers have the ability to improve membrane flux and antifouling property. Copolymers are also able to induce responsive properties in membranes. It is highly desirable to provide a protocol to obtain a library of copolymer modified membranes. Herein, we report a general and convenient approach for the preparation of pH or temperature or simultaneous pH and temperature responsive high flux and low fouling polyvinylidene fluoride (PVDF)/copolymer blend ultrafiltration membranes by conventional phase inversion process. The approach was based on blending PVDF with library of amphiphilic random copolymers containing a common hydrophobic polymer component which is compatible with PVDF Poly(methyl methacrylate) (PMMA)-co-X copolymers [where X=poly (dimethylaminoethyl methacrylate) (PDMA), poly(acrylic acid) (PAA), poly(N-isopropyl acrylamicle) (PNIPAM), poly(N,N-dimethyl acrylamide) (PDMAA), poly(N-vinyl pyrroliclone) (PVDF), PDMA-co-PNIPAM, PAA-co-PNIPAM and PDMA-co-PDMAA] are such versatile blending agents for PVDF, easily synthesized by conventional free radical polymerization. The structural effects of X on the membrane pore radius, porosity, permeate flux, responsive behaviour and fouling resistance ability was systematically studied. The beneficial effect of PMMA as a common polymer component in the amphiphilic copolymers for the preparation of blend membranes is attributed to the compatibility of PMMA with PVDF which lowers the phase separation in casting solutions for further phase inversion and enhances the stability of the copolymers in the membrane matrix owing to the enhancement of interfacial adhesion between copolymer and PVDF. This approach is promising for the preparation of library of PVDF/copolymers blend membranes and screening of membranes thereof for further applications. (C) 2015 Elsevier B.V. All rights reserved.
Keywords:PVDF/copolymers blend ultrafiltration membranes;PMMA-based copolymers;Stimuli responsive membranes;Low fouling membranes;Screening of membranes