Comparative Studies Regarding the Synthesis and Characterization of Cellulose Based-Polymer Assemblies for Fuel Cell Applications

The aim of these comparative studies consists of synthesis and characterization of membrane assemblies from cellulose acetate (CelAc) and acrylic acid (AA), using as dopant in-situ generated pyrrole–aniline (Py–AN) copolymer intended for use in fuel cells fabrication. The synthesis was conducted through free radical polymerization in a semi-homogeneous system and the casting method was used to form the solid polymer membranes. In selecting the optimal compositional parameters, the influence of the molecular size of the majority matrix component was also observed. These membrane assemblies were studied using FT-IR spectroscopy, UV-Vis spectroscopy, and X-Ray diffraction analysis which highlighted the structure–composition dependence. With the electrochemical impedance spectroscopy the ionic conductivity of the membrane was determined, in order to evaluate the PEM fuel cell performance. In case of thicker membranes, there is an increase in ionic conductivity values over those of lower thickness, which is due to short-order structural order. Also, a superunitary Py:AN is more favorable to conductivity increase than a less than one ratio.