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Organic–inorganic hybrid coatings were formulated using multifunctional vinyltrimethoxysilane (VTMS) oligomers and acrylated polyester (AP). A radical photoinitiator was added to the VTMS/AP formulation and the films were crosslinked via UV‐radiation. The viscoelastic, thermomechanical, and surface properties of the VTMS/AP films were evaluated as a function of VTMS content, using dynamic mechanical thermal analysis (DMTA), thermal gravimetric analysis (TGA), contact angle, fracture toughness, and tensile properties. In addition, coating properties such as adhesion, scratch resistance, pencil hardness, and impact resistance were also investigated. The tensile and scratch data show that VTMS oligomer dramatically increased hardness and scratch resistance. The VTMS oligomer also increased the contact angle, led to a decrease in surface tension, and improved surface appearance. The VTMS oligomer also increases storage modulus, glass transition temperature, and crosslink density. The morphology of films and the particle size were observed using atomic force microscopy (AFM). The data indicated that the average silica particle size was ∼90 nm and the particles were well‐dispersed in the organic phase. It was postulated that the VTMS oligomer functioned effectively as a hyperbranched crosslinker, surface modifier, and reactive diluent. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 105:2376–2386, 2007 [ABSTRACT FROM AUTHOR]

The chain‐end‐group composition was determined by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) analyses of low‐molecular‐weight polystyrene (PS) and poly(methyl methacrylate) (PMMA) produced by free‐radical polymerization with a monoacylphosphine oxide, (2,4,6‐trimethylbenzoyl) diphenylphosphine oxide (TPO), as a photoinitiator. Gel permeation chromatography (GPC) fractionation of the PS and PMMA samples with initial polydispersities of 1.81 and 2.81, respectively, yielded improved MALDI‐TOF MS spectra. Spectral analyses of the PS fractions showed distributions attributable to PS having two diphenylphosphinyl ends and PS having one diphenylphosphinyl end and/or one 2,4,6‐trimethylbenzoyl end, indicating that a combination of PS radicals with the highly reactive diphenylphosphine oxide group at one end of the chains was the predominant mode of termination. MALDI‐TOF MS results for PMMA fractions provided evidence for termination primarily by disproportionation, but structure determination was confounded by the presence of isobaric peaks. Discernible peaks were obtained by MALDI‐TOF MS analyses of GPC fractions of TPO‐initiated poly(methyl‐d3 methacrylate‐d5), in which the major product was PMMA with a diphenylphosphinyl end group and an abstracted deuterium end group, whereas the minor combination product had two diphenylphosphinyl chain ends. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2161–2171, 2007 [ABSTRACT FROM AUTHOR]

Hexagonal PdII- or CdII-tetrakispyridinyl-based macrocycles are quantitatively self-assembled from 4′-(3-pyridinyl)-4,4′′-di(tert-butyl)-2,2′ : 6′,2′′-terpyridine and structurally confirmed by NMR and TWIM-MS. [ABSTRACT FROM AUTHOR]