(128b) Sulfonated Perfluorocyclobutyl Polymers and Fluorocarbon Functionalized Carbon for Pem Membranes

Novel ways of using perfluorocyclobutyl (PFCB) based polymer systems as proton-exchange membranes will be discussed. PEMs based on direct sulfonation of bisphenyl-PFCB polymer derived from biphenyl trifluorovinylether (BPVE) monomer have been investigated. Direct sulfonation of the PFCB polymer provide an efficient way to control the degree of sulfonation. The sulfonated polymer also formed stable free standing films that were solution cast from DMAc. In addition, we have also investigated a new class of sulfonated poly(arylene ether sulfone) (PAES) containing the perfluorocyclobutyl (PFCB) unit, prepared by the polycondensation of a unique bis-phenol (Bisphenol?T) with two dichlorodiphenylsulfones (DCDPS) under nucleophilic substitution conditions. The incorporation of the sulfonated repeat unit into the copolymers was determined by NMR and FTIR. The resulting polymers show good solubility in polar organic solvents such as DMSO, DMAc and form tough, flexible films by solution casting. The polymers exhibit glass transition temperature near to 130 °C and catastrophic weight loss in nitrogen at 350-450 °C. We have also developed a number of porous carbons from polymeric precursors. Both traditional resorcinol-formaldehyde resin and BODA nanomolding chemistries were utilized to yield porous carbons of different pore sizes, for potential use as a self-supporting solid electrode with reliable electrical conductivity. Decoration of the carbon electrode surface with compatibilizing fluoropolymer and fluorinated acid sites, through aromatic diazonium salts will be investigated in this work.