Proton exchange membranes based on semi-interpenetrating polymer networks of Nation® and poly(vinylidene fluoride) via radiation crosslinking

摘要

A new method to prepare proton exchange membranes based on semi-interpenetrating polymer networks (semi-IPN) of Nafion~® and polyfvinylidene fluoride) (PVDF) via radiation crosslinking was proposed. The tensile strength, degree of crosslinking, water uptake, and swelling ratio of the composite membranes were studied. Compared to the recast Nafion~®212 membrane, the composite membranes show much better mechanical properties and improved dimensional stability. The tensile strength of the composite membranes ranges from 34.3 MPa to 53.4 MPa, which is higher than that of the recast Nafion~®212 membrane (23.9 MPa). The dimensional stability of the composite membranes also increases with increasing PVDF content in the membranes. The composite membranes show considerable proton conductivity even at 100-120 ℃. The membrane containing 40% PVDF shows the highest proton conductivity of 3.37 × 10~(-2/) S/cm at 115 ℃. These properties make them a great potential in polymer electrolyte membrane fuel cells (PEMFC).