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A series of novel fully aromatic poly(arylene ether sulfone)s that contain 1,3,5-s-triazine groups were synthesized by the reaction of triazine-containing bisphenols with bis(4-fluorophenylsulfone) to study the effects of branching groups on solubility as well as thermal and mechanical properties. Polymers had inherent viscosities from 0.43 to 1.10 dL/g, thermal stabilities >500 °C in air, glass transition temperatures from 136 to 289 °C, and good film forming abilities. The polymer with pendant diphenylamine groups on the triazine ring were further investigated for use in proton exchange membranes based on solubility, thermo-oxidative stability, and ease of monomer synthesis. A series of copolymers made from 4,6-bis(4-hydroxyphenyl)-N,N-diphenyl-1,3,5-triazin-2-amine and 4,4′-biphenol were sulfonated with chlorosulfonic acid to achieve ion exchange capacities up to 2.62 mmol/g. The homopolymer was sulfonated exclusively on the diphenylamine branch and had the highest proton conductivity (0.11 S/cm at 95 °C and 100% relative humidity), even though it had the lowest water uptake and ion exchange capacity. Unsulfonated polymers and sulfonated copolymers showed little uptake of phosphoric acid. However, the sulfonated homopolymer with pendant diphenylamine groups had a 200−250 wt % uptake when soaked in 85% H3PO4at 90 °C, but the proton conductivity of this polymer was lower than the hydrated polymer without H3PO4added. [ABSTRACT FROM AUTHOR]

Solvent-free polymer electrolytes were made consisting of Liand pyrrolidinium salts of trifluoromethanesulfonimide added to a series of hyperbranched poly(ethylene oxide)s (PEO). The polymers were connected by triazine linkages and cross-linked by a sol−gel process to provide mechanical strength. These electrolytes are more conductive than those made with high molecular weight PEO imbibed with ionic liquids at ambient temperatures, due to the amorphous nature of the polymer. The connecting PEO groups were varied to help understand the effects of polymer structure on electrolyte conductivity in the presence of ionic liquids. Polymers were also made that contain poly(dimethylsiloxane) groups, which provide increased flexibility without interacting with lithium ions. When large amounts of ionic liquid are added, there is little dependence of conductivity on the polymer structure. However, when smaller amounts of ionic liquid are added, the inherent conductivity of the polymer becomes a factor. [ABSTRACT FROM AUTHOR]

A series of poly(pyridinium triflate)s with alkyl and aromatic spacer groups were prepared by ring transformation polymerizations between various pyrylium triflates and diamines. The polymers are soluble in polar aprotic solvents and form tough, clear, flexible films. These novel polymers were characterized by IR, NMR, UV, DSC, TMA, and TGA. The polymers were thermally stable to 340 °C under nitrogen, and had softening points that ranged from 151 to 255 °C. Thin films were shown to display electrostrictive behavior in the presence of an applied electric field, with the amount of transverse strain being proportional to the concentration of charge in the polymer. [ABSTRACT FROM AUTHOR]