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A series of sulfonated poly(arylene ether sulfone) (BPSH-BPS) multiblock copolymer (MBC) ionomers were studied with respect to structure and physical properties. Ion exchange capacity (IEC w ) on a weight basis was constant for all MBC ionomers with controlled ionic and nonionic block lengths of 5k:5k, 10k:10k and 15k:15k. Viscoelastic properties were investigated as a function of block length,...
Lightly sulfonated syndiotactic polystyrene (sPS) nanocomposites were prepared using a solution intercalation technique, and the effect of montmorillonite clay on the crystallization kinetics of sulfonated sPS ionomer nanocomposites was systematically studied. Wide angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM) were used to evaluate the dispersion of clay platelets within...
The effects of block length and solution-casting conditions on the final microstructures and properties of disulfonated poly(arylene ether sulfone) multiblock copolymer (BPSH100–BPS0) films for proton exchange membranes were investigated based on the basic principles of microstructure formation of block copolymers. Morphological studies using transmission electron microscopy and small angle X-ray...
Perfluorosulfonate ionomers (PFSIs) neutralized by tetraalkylammonium ions have been investigated using variable temperature 1 H and 13 C solid-state NMR (ssNMR) spectroscopy to probe the thermally induced properties of tetraalkylammonium ions at temperatures near the α-relaxations. Tetramethylammonium (TMA + ), tetraethylammonium (TEA + ), tetrapropylammonium (TPA...
H + -form Nafion 212 films were chemically degraded via Fenton's reagent and characteristic polymer chain motions were analyzed using broadband dielectric spectroscopy. The β-relaxation peak maximum frequency (f max ) shifts to higher temperatures upon degradation, reflecting slower chain motions. Perhaps this is due to an upward shift in average molecular weight caused by low molecular...
Blends of poly(vinylidene fluoride) (PVDF) with a perfluorosulfonate ionomer, Nafion ® , have been prepared and examined in terms of the crystallization kinetics of the PVDF component. In blends of PVDF with Na + -form Nafion ® , the rates of bulk crystallization, as observed by DSC, and the spherulitic growth rates of the PVDF component, as observed using optical microscopy,...
Sulfonated ethylene vinyl alcohol copolymers have been synthesized and artificial muscles have been produced from this new class of ionomeric membrane materials. FTIR spectroscopy confirmed the modification through introduction of peaks characteristic of ester linkages between sulfosuccinic acid and vinyl alcohol. Solid-state 23 Na NMR showed the ionic functionalities aggregate during membrane...
Poly(ethylene terephthalate) ionomer (PETI)/organically-modified montmorillonite clay (OMC) nanocomposites were prepared via melt extrusion. Sulfonated PET containing various incorporations of ionic comonomer and clay modifications were investigated. The random incorporation of ionic functionalities along the PET backbone enhances interactions between the matrix polymer and montmorillonite clay resulting...
The influence of ionic comonomer units and ionic aggregation on the crystallization behavior and crystallite surface energies of poly(butylene terephthalate-co-5-sodiosulfoisophthalate) (PBTi) ionomers containing 3 and 5mol% dimethyl-5-sodiosulfoisophthalate monomer units is compared to that of pure poly(butylene terephthalate). The rate of crystallization of the ionomers, as determined from an Avrami...
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