Polyamide/Polystyrene Blend Compatibilisation by Montmorillonite Nanoclay and its Effect on Macroporosity of Gas Diffusion Layers for Proton Exchange Membrane Fuel Cells

Abstract

This work deals with a new route to modify polymer blend morphology in order to improve the porosity of gas diffusion layers (GDLs) for proton exchange membrane fuel cells (PEMFCs). First, electrically conductive polymer‐based blends were carefully formulated using a twin‐screw extrusion process. Blend electrical conductivity was ensured by the addition of high specific surface area carbon black and synthetic graphite flakes. Final GDL porosity, in particular its macroporosity, was generated by melt blending polyamide 11 (PA11) matrix with polystyrene (PS) followed by PS extraction with tetrahydrofuran (THF) solvent at room temperature. In order to improve GDL porosity by the optimisation of PS dispersion in the PA11 matrix, PA11/PS blends were compatibilised by the addition of 2 wt.‐% of clay. It was observed that both macroporosity and pore size distribution were beneficially modified after blend compatibilisation. Final GDL conductivity of about 1.25 S cm–1, a porosity of 53% and a specific pore surface area of 75 m2 g–1 were achieved.

Conductive Materials for Proton Exchange Membrane Fuel Cell Bipolar Plates Made from PVDF, PET and Co‐continuous PVDF/PET Filled with Carbon Additives

“…Only Rabinovitch correction was performed on the measured data. The experimental technique ( Figure 2) used to measure the electrical resistance, R X, of the extruded films is described in a previous work [21]. The volume resistivity, q X cm, is then obtained using the following relation:…”

Polymer-Layered Silicate Nanocomposite Membranes for Fuel Cell Application

“…PWA being highly conducting in nature compared to the clay, addition of MMT to PVOH-PWA composite resulted in a decrease in the conductivity of the PVOH-PWA-MMT composite compared to the PVOH-PWA composite [110]. In a similar study, addition of MMT (Cloisite 30B) to the highly conductive PAM-PS blend decreased the proton conductivity of the nanocomposite membrane compared to the PAM-PS blend [119]. Hence, despite the high hydrophilicity of nanoclays, degrees of dispersion of nanoclays in the polymer matrix play a vital role in improving the proton conductivity of the nanocomposites.…”

Surface modification of multiwall carbon nanotubes and its effect on mechanical and through‐plane electrical resistivity of PEMFC bipolar plate nanocomposites

“…The discs were pressed between 2 highly conductive cylindrical gold‐plated electrodes under a force of 450 N and an imposed current I = 5A. The experimental techniques used are already presented in a previous work . The volume resistivity ρ (Ω cm) is calculated using the following equation: where D (cm) is the electrode diameter, h (cm) is the sample thickness, and R (Ω) is the sample electrical resistance (after subtracting carbon cloth resistance).…”