Preparation and characterization of heterogeneous anion exchange membranes based on poly (methyl methacrylate), poly (vinyl chloride) and functionalized carbon nanotubes

Nanocomposite anion exchange membranes were prepared using polymeric blend of poly(vinyl chloride) and poly(methylmetacrylate) by solution casting method. Also functionalized carbon nanotubes were used as additive. The carbon nanotube nanoparticles were modified using acid mixtures and ethylenediamine solution and then the structure and morphology of prepared functionalized carbon nanotubes were studied using infrared spectroscopy (FT-IR) and field-emission scanning electron microscopy (FE-SEM). The study of the physicochemical and electrochemical properties of prepared membranes showed that the water content, ion exchange capacity, membrane potential, transport number, surface charge density and permselectivity of them were improved by adding up to2% by weight of carbon nanotubes. Also, the permeability, flux, electrical resistance and chemical stability of prepared membranes with carbon nanotube increased compared to the nanotube-free membranes.In fact, the high active level and the effect of the functionalized carbon nanotube on increasing the hydrophilicity and the transfer properties of the membranes have created suitable ion channels and facilitated ion transport. By adding nanoparticles up to 4% by weight, the electrochemical properties of the prepared membranes were reduced slightly. This can be attributed to the blockade of functional groups by nanoparticles and the accumulation of carbon nanotubes.