Investigation of nanocomposite membranes based on crosslinked poly(vinyl alcohol)–sulfosuccinic acid ester and hexagonal boron nitride

Abstract

Hexagonal boron nitride (hBN) has received a great deal of attention from the scientific community owing to its distinctive mechanical properties, chemical stability, electrical features, and thermal stability. This work reports the preparation and characterization of novel anhydrous proton-conducting nanocomposite membranes based on poly(vinyl alcohol) (PVA), sulfosuccinic acid (SSA), and hBN. The proton conductivities of composite membranes were examined as a function of hBN composition and temperature. SSA was used as a sulfonating agent to obtain a crosslinked structure. hBN was incorporated into the PVA–SSA matrix as a proton transfer agent and nanofiller additive. The obtained membranes were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), water uptake, methanol permeability, and impedance spectroscopy. The semicrystalline nature of the composites was confirmed by X-ray investigation. The PVA–SSA–15hBN showed a maximum proton conductivity of 0.028 S cm−1 at 150 °C under anhydrous conditions.