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Rutile TiO 2 was formulated into polyurethane/polysiloxane hybrid coatings in order to investigate the influence of pigmentation on the inorganic phase of the hybrid coatings. Two urethanes were prepared from the isocyanurate of hexane diisocyanate (HDI), alkoxysilane modified HDI, and tetraethyl orthosilicate (TEOS) oligomers, with oligoesters derived from either cyclohexane diacids (CHDA) and 2-butyl-2-ethyl-1,3-propanediol (BEPD) or adipic acid (AA), isophthalic acid (IPA), 1,6-hexanediol (HD), and trimethylol propane (TMP). The oligoesters were spectroscopically characterized using GPC, FT-IR, and NMR. Chemical interaction between the TiO 2 and the sol-gel precursor was investigated using solid-state 29 Si NMR and XPS. The morphology, mechanical, viscoelastic, thermal properties of the pigmented coatings are evaluated as a function of pigmentation volume concentration (PVC). Using AFM and SEM, the pigment was observed to be well dispersed in the polymer binder. The thermal stability, the tensile modulus, and strength of the coatings were enhanced with increasing PVC, whereas the pull-off adhesion and flexibility (elongation-at-break) were reduced with increasing PVC. Finally, the pigmented coatings were evaluated by electrochemical impedance spectroscopy (EIS) and the results showed that 10 wt % of the pigment improved the corrosion resistance of the entire coating system.

The feasibility of poly(vinyl alcohol)(PVA)/sulfosuccinic acid(SSA)/heteropolyacid (HPA) composite membranes was investigated to apply for direct methanol fuel cells (DMFC). The composite membranes were prepared by the solution casting method and their properties were examined. The FTIR spectra showed that the Keggin unit of HPA was preserved in the composite membranes and that specific interactions were involved between PVA and HPA. The composite membranes showed uniform distribution of PWA particles in the PVA/SSA/PWA composite membranes by FE‐SEM. The HPA bleeding out was observed to decrease with increasing HPA concentration. The proton conductivity of PVA/SSA/HPA composite membranes improved at low HPA concentration (5‐10 wt.%), while those properties decreased as HPA concentration increased over 10 wt.%.

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