Proton exchange membrane from the blend of poly(vinylidene fluoride) and functional copolymer: Preparation, proton conductivity, methanol permeability, and stability

A polymer electrolyte membrane is considered as the heart of fuel cells. Here we report the preparation of proton exchange membranes (PEMs) of poly (vinylidene fluoride) (PVDF) blend poly (methyl methacrylate)-co-poly (sodium-4-styrene sulfonate) (PMMA-co-PSSNa) by solvent evaporation method. Three different types of PEMs have been prepared by using different ratios of PVDF and PMMA-co-PSSNa copolymer. We have investigated the effect of concentration of PVDF on water uptake, ion exchange capacity, mechanical, thermal, and oxidative stability, proton conductivity (Km), and methanol permeability (PM) of the blend membranes. These blend PEMs showed good physicochemical and electrochemical prop-erties along with thermal and oxidative stability. The membrane prepared from PVDF (45% w/w) to PMMA-co-PSSNa (55% w/w) exhibited optimum PM at room temperature (8.38 x 10-7 cm2s-1). This low fuel crossover and high relative selectivity can make our prepared blend membranes a potential candidate in polymer electrolyte membrane fuel cells (PEMFCs) or direct methanol fuel cells (DMFCs).(c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study reports the preparation of proton exchange membranes using a solvent evaporation method. The membranes are composed of a blend of poly (vinylidene fluoride) and poly (methyl methacrylate)-co-poly (sodium-4-styrene sulfonate) copolymer. The blend membranes exhibited good physicochemical and electrochemical properties, as well as thermal and oxidative stability. The membrane with a PVDF concentration of 45% showed the optimum methanol permeability, making it a potential candidate for fuel cells.