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In this study, we synthesized MPPG including the methylene-oxy group from polypropylene glycol (PPG) with the molecular weight (g/mol) of 200. Also UV curable resins were prepared from the mixture of polyurethane acrylate (PUA) oligomer which was synthesized with synthesized MPPG, TMPTA, HDDA, and HP-8 to investigate the possibility of its application for optical film materials. The Tgwas higher for UAMP oligomer with MPPG as well as MPPG than that of PPG and UAP oligomer. The refractive index and the pencil hardness of UCM were higher than those of UC while the optical transmittances of UCM and UC were much the same. [ABSTRACT FROM AUTHOR]

A new class of thiophene-based cholesteryl and ferrocenyl derivatives was synthesized and characterized by common analytical techniques. Liquid-crystalline properties were investigated by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). Thiophene-based cholesteryl derivatives show homeotropic liquid-crystalline phase sequence crystal → smectic A → cholesteric → isotropic, whereas the ferrocenyl derivative is nonmesomorphic. The effects of thiophene ring, terminal group, and length of the polymethylene spacers on the mesomorphic behavior are discussed. [ABSTRACT FROM AUTHOR]

Polymethylsilsesquioxane(PMSQ)s with photo-curable groups were prepared by copolymerization of alkoxysilanes. Poly(acryloyl-co-methylsilsesquioxane)(PAMSQ)s of various mole ratio acryloyl group (6 mol%, 12 mol%, 24 mol%, 48 mol%, 100 mol%) were obtained from copolymerization of methyltrimethoxylsilane and 3-(trimethoxysilyl)propyl acrylate. Optical and photonic curable properties were studied by near infrared region spectra, prism coupler, UV-visible spectra, and photo-DSC. The optical losses were below 0.002 dB/cm at 830, 1330, and 1550 nm, respectively. Optical loss was found to be independent of a molar ratio of functional group. [ABSTRACT FROM AUTHOR]

The process of radical thermo-initiated polymerization of DMF (dimethylformamide) MMA (methylmethacrylate) solutions is investigated kinetically. It is shown that the reaction occurs in the presence of symmetric cation polymethine dyes containing terminal groups of strong, moderate, and weak electron-donating abilities. It is established that, with growing the terminal group electron-donation, an increase of the monomer conversion occurs at the same reaction times. Using DFPH (diphenylpicrylhydrazyl), it is shown that the process is to be considered as a radical one. [ABSTRACT FROM AUTHOR]

We have shown that a charged trion consisting of two on-chain polarons of the same sign and a trapped polaron of the opposite sign can be metastable with respect to both dissociation and recombination. A trion can be created upon fusion of a free polaron with a neutral pair, which eliminates a high Coulomb potential barrier for fusion of two charge carriers into a bipolaron. We argue that trions can be created by photoexcitation of a conjugated polymer, in which illumination creates a high density of geminate pairs. Since the metastable trion is anchored by a deep-trapped charge, it is immobile and can be considered as a coulombically trapped bipolaron, although the last may not exist as a free particle. We employ the concept of localized trions in order to explain the reversible photoinduced fatigue of thermally stimulated luminescence in films of poly[methyl(phenyl)silylene]. [ABSTRACT FROM AUTHOR]