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Soluble phenol formaldehyde resin containing hydroxymethyl groups has been used to modify sulfonated poly(ether ether ketone) (SPEEK). Modification has been carried out with films containing both the polymers and using dimethyl formamide (DMF) as casting solvent at various temperatures under reduced pressure. Associated solvent and the hydrogen-bonded by-product dimethyl amine (DMA) were removed through mild alkali-acid-water treatment. Cured and treated films show good and consistent mechanical properties, water uptake (22-25%), ion-exchange capacity (1.1-1.5 meq/g) and proton conductivity (125-150 mS/cm) at 308C and hold promise for application in fuel cells, as indicated by a polarization study in a fuel cell test station.424 P. C. Deb et al.Ã The values in parentheses were determined from as-molded blends. The standard deviations of 5 measurments in E-modulus and tensile Strength were less than 3% and the ones of elongation at break were less than 5%.

Transition metal complexes of linear and crosslinked styrene‐maleic acid copolymer were prepared in ethyl alcohol. The complexes appear as micro clusters fairly uniformly distributed in the copolymer matrix. Vapor adsorption–desorption studies of the complex beads with methyl isobutyl ketone (MIBK), toluene and ethyl alcohol show initial fast release followed by a steady and slow release. Hydrogen adsorption at room temperature was studied for a few complexes up to about 650 torr, which showed initial slow adsorption followed by a rapid increase at about 550 torr. Copyright © 2005 John Wiley & Sons, Ltd.