Phosphonate poly(vinylbenzyl chloride)-Modified Sulfonated poly(aryl ether nitrile) for Blend Proton Exchange Membranes: Enhanced Mechanical and Electrochemical Properties

Blend proton exchange membranes (BPEMs) were prepared by blending sulfonated poly(aryl ether nitrile) (SPAEN) with phosphorylated poly(vinylbenzyl chloride) (PPVBC) and named as SPM-x%, where x refers to the proportion of PPVBC weight SPAEN. The chemical complexation interaction between phosphoric acid sulfonic groups in PPVBC–SPAEN system resulted BPEMs reduced water uptake enhanced mechanical properties compared SPAEN membranes. Furthermore, flame retardancy improved thermal stability BPEMs. Despite a decrease ion capacity, conductivity through-plane direction was significantly due introduction groups, especially low relative humidity (RH) environments. measured SPM-8% 147, 98, 28 mS cm−1 under 95%, 70%, 50% RH, respectively, which is higher than that unmodified membrane other SPM-x% Additionally, morphology anisotropy conductivities analyzed discussed. Overall, results indicated doping can effectively enhance electrochemical