Fuel Cell Application of High Temperature Polymer Electrolyte Membranes Obtained by Graft Copolymerization of Acrylic Acid and 2-Hydroxyethylmethacrylate on ETFE Backbone Material

Abstract

Proton exchange membranes for high temperature fuel cell applications were obtained via graft copolymerizations on commercial poly(ethylene-alt-tetrafluoroethylene) (ETFE) films. ETFE was activated by electron beam treatment, and the hydrophilic monomers acrylic acid and hydroxyethyl methacrylate were grafted to ETFE. The maximum grafting level was 620%. The grafted membranes were doped with the proton carrier phosphoric acid leading to a maximum doping level of 450%. Stress-strain measurements indicate good mechanical stability of the composite membranes. The polymer-acid membranes were tested in a H 2 /O 2 fuel cell. At a current density of 200 mA Á cm À2 a stable power density of 113 mW Á cm À2 was determined at 120 8C. The results show that high phosphoric acid contents associated with high proton conductivity may be obtained with a copolymer containing acrylic acid.

Microstructure and sulfonation of dual monomer‐grafted polypropylene nonwoven fabrics

“…Totura insisted that the ion exchange resin of diphosphonic acid reacted completely with metal ions in solution, while not being consumed by alkaline earth metal elements, but the inclusion of sulfonic group in the resin would improve ion access to the diphosphonic sites and speed exchange rate . Proton exchange membranes for high temperature fuel cell was developed by grafting copolymerization of AA and hydroxylethyl methacrylate onto poly(ethylene‐alt‐tetrafluoroethylene) film in order to overcome a low binding capacity of AA with phosphoric acid . During electrodeionization process, carboxylic‐type exchange resins have weak ion adsorption, strong desorption, and poor conductivity, vice versa for sulfonic‐type exchange resins .…”

Fabrication and investigation of phosphoric acid doped imidazolium siloxane crosslinked poly(2,6‐dimethyl‐1,4‐phenylene oxide) for high temperature polymer electrolyte membranes

“…Thus the development of alternative superior membrane electrolytes for HT‐PEMs is strongly desired. Several functionalized polymeric materials with excellent thermal stability and high PA doping capability have been proposed to fabricate HT‐PEMs, such as quaternary ammonium/imidazolium group side‐chain grafting of poly(aromatic ether)s and pyridine/pyrrolidone/acrylic acid group main‐chain containing polymers.…”

Preparation of Polymer Electrolyte Membranes via Radiation-Induced Graft Copolymerization on Poly(ethylene-alt-tetrafluoroethylene) (ETFE) Using the Crosslinker N,N′-Methylenebis(acrylamide)

“…One example are strategies employing a commercial poly(ethylene-alt-tetrafluoroethylene) (ETFE) base material. Previously, we reported on high temperature polymer electrolyte membranes (HTPEM) based on induced graft copolymerization of (meth)acrylate monomers on ETFE backbone material after electron beam (EB) treatment and subsequent doping with phosphoric acid [31,32]. In contrast, generally PEMs with an operating temperature below 100 °C (low temperature polymer electrolyte membranes, LTPEM) contain sulfonic acid groups, which are nowadays most commonly used in fuel cell vehicles.…”