Novel Aromatic Polymers with Pendant Lithium Perfluoroalkylsulfonate or Sulfonimide Groups

Styrenes with pendant lithium perfluoroalkyl ether sulfonate or sulfonimide groups readily homopolymerized and copolymerized with olefinic monomers to provide moderate to high molecular weight ionomers. Comonomers included styrene, methyl methacrylate, acrylonitrile, and acrylates. In addition, soluble polymers containing both mobile lithium ions and immobilized tetraalkylammonium cations were prepared. Cross-linked polymers were obtained by copolymerization of the functionalized styrenes with difunctional comonomers or by cocuring with an unsaturated elastomer. Polyesters with pendant lithium perfluoroalkylsulfonate groups were obtained by condensation polymerization of functionalized isophthalate monomers with bis(hydroxyethyl)terephthalate. Surprisingly, most of the ethylene glycol units in the polymers were converted into poly(ethylene glycol) segments during polymerization. Lithium ion conductivities of 10-4−10-3 S/cm were shown by selected polymers in solution or as solvent swollen films.