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The fluorene diol (I) has been chemically incorporated into a sol-gel formulation that was coated to produce a thin overcoat on an organic photoreceptor and cured into a silsesquioxane matrix that efficiently transports holes. The residual potential of the photoreceptor decreased as the amount of hole transport material (I) incorporated into the silsesquioxane matrix was increased. The charge transport was independent of humidity. At 30 wt.% the residual potential is identical to that of a photoreceptor without an overcoat. This methodology produces an organic photoreceptor with a protective overcoat without compromising the electrophotographic characteristics.

Fatigue-resistant elastomers have been prepared using various metal oxides as fillers in poly(dimethylsiloxane) (PDMS)-based elastomers. The judicious choice of inorganic fillers produced elastomers that were stable under cyclic testing at elevated temperatures. These experiments were carried out using the Mechanical Energy Resolver, an instrument modified to reduce testing time from approximately 6 weeks to 60 h. Four elastomers showed stable storage moduli, were creep resistant, and showed less than 1% weight loss after 60 h. By comparison, a formulation prepared with alumina as the filler showed high rates of creep and greater than 10% weight loss. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 1633–1641, 1998

The miscibility between polyitaconates [CH 2 C(COOR)(CH 2 COOR)] x [CH 2 C(COOH)(CH 2 COOR)] y (R= (CH 2 CH 2 O) m CH 3 m= 2,3; x=0.7 y= 0.3; x=1 y= 0) and polyacrylates [CH 2 C(Me)(CO[OCH 2 CH 2 ] 2 OCH 3 )] n and polymers bearing an acidic functionality, such as poly(vinylphenol) (PVPh) and its copolymers with styrene, and poly(styrene-co-styrene-4-sulfonic acid), is investigated. Heats of mixing measurements are performed on model compounds of these polymers, revealing that the interactions are dominated by the etheric side chains, even though the polyitaconates also contain carbonyl groups that are good hydrogen bond acceptors

The synthesis and characterization of poly(itaconate ester)s with short poly(ethylene oxide) side chains have been studied. It was found that the monomer syntheses via esterification of itaconic acid resulted in incomplete esterification leaving up to 35 mol % monomers with carboxylic acid functionality. These acid groups were then incorporated into the polymers. This acid incorporation has not previously been reported, nor have the properties of the copolymers been studied. Techniques were developed to effectively remove the acid impurities to generate pure homopolymers. Titration and gas chromatographic techniques were developed to study the amount of acid impurity in the monomers, and titration was also used to characterize the polymers. Size exclusion chromatography and differential scanning calorimetry were used to study both the homopolymers and copolymers. It was found that the location and breadth of the glass transition is a function of acid content. Finally, isomerization of the itaconate monomers to the inactive mesaconate was also found to be a problem during the synthesis. Pure mesaconate and citraconate monomers were synthesized and characterized by 1H-NMR. © 1993 John Wiley & Sons, Inc.

The presence of acidic or proton-donating functional groups on the organic polymer is shown to increase the miscibility of the organic polymer with polyphosphazenes containing ethyleneoxide side chains. Thus, poly(vinylphenol) (PVPh) is miscible over the entire composition range with poly[bis(methoxyethoryethoxy)phosphazene] (MEEP) and with poly[bis(methoxyethoxyethoxyethoxy)phosphazene] (MEEEP) but is not miscible with poly[bis(triluoroethoxy)phosphazene] or with poly[bis(phenoxy)phosphazene]

A variety of inorganic fillers are investigated to determine their impact on the response of filled polysiloxane elastomers to cyclic stress in hot air and in hot poly(dimethylsiloxane) PDMS fluid environments. Three fillers stabilize the polysiloxane networks to cyclic stress: zinc oxide, tin oxide, and copper oxide. Four fillers enhance network degradation: aluminum oxide, calcium oxide, titanium oxide, and tungsten oxide. The roles of testing environment, of diphenylsiloxane content of the polysiloxane network, of filler loading, of the stoichiometric balance of network precursors, and of molecular weight between cross-links are investigated. Although each influences the response of the elastomer to cyclic stress at elevated temperature, filler type exerts the primary influence. Silane-treated fillers are used to demonstrate that differences based on filler type do not arise because of changes in the strength of polymer-filler interactions. No correlation between stability of the filled elastomer to cyclic stress in hot air and filler particle size distribution, filler surface acid/base character, or the presence of specific inorganic contaminants in the filler is observed. It is proposed that the intrinsic ability of certain inorganic oxides to catalyze and/or inhibit polysiloxane degradation reactions determines the response of the filled elastomers to cyclic stress at elevated temperature.

Dimethylarsine, (CH3)2AsH, and dimethylhalo(or pseudohalo)arsines, (CH3)2AsX, X = Cl, Br, I or CN, reversibly form tetramethyldiarsine and HX in benzene. As followed by pmr spectroscopy, several pmr-rapid processes are observed which involve the exchange of parts among equilibrium components. Where available, equilibrium and thermodynamic parameters have been obtained. The activational parameters for the exchange processes suggest that exchange occurs through an associative intermediate. When X = Br or I, significant quantities of H2 are also found.

The adsorption of poly[N-(m- and p-vinylbenzyl)-N,N,N-trimethylammonium tetrachloropal-ladate] complex on inorganic oxide surfaces followed by reduction of the palladium salt to form a catalytically active zerovalent metal polymer composite dispersed on the oxide surface and further deposition of transition metals, e.g., nickel, cobalt, and copper, by “additive” or “subtractive” deposition from electroless plating solutions is described. γ-Ferric oxide was used as a template for such intermetallic replacement reactions, providing materials with controlled amounts of metal. Multimetallic catalysts based on aluminum oxide, zinc oxide, lanthanum oxide, magnesium oxide, and silica were prepared. Iron oxide modified by subtractive deposition of rhodium and iridium on nickel-clad iron oxide were evaluated in Fischer–Tropsch carbonylation reactions leading from synthesis gas to alkanols.