Hybrid membranes based on silica and 2-hydroxyethylmethacrylate–4-vinylpyridine copolymers

Abstract

4-Vinylpyridine–2-hydroxyethylmethacrylate copolymers have been synthesized by radical copolymerization. The composition and properties of the copolymers have been studied; the reactivity constants of the comonomers have been calculated. Sol–gel synthesis involving the resulting copolymers and tetraethoxysilane has yielded hybrid membranes comprising a polymer matrix with uniformly distributed hydrated silica particles and exhibiting a proton conductivity of up to 1.85 × 10⁻² S/cm, an ion-exchange capacity of 2.1 meq/g, a heat resistance of 412°С, a tensile strength of 55.5 MPa, an elongation at break of 15%, and a proton-conductivity activation energy of 12 ± 2 kJ/mol.