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Yasumasa Toba;Midori Saito
- Journal of Photoscience
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- v.5 no.3
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- pp.111-120
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- 1998
Sensitized photolysis of two onium borates (diphenyliodoium and dimethylphenacylsulfonium tetrakis(pentafluorophenyl)borate, 1a and 2a , respectively) and cationic photopolymerization of an epoxy monomer by the photolysis were investigate. The onium borates were sensitized by the excited singlet of the athracenes(non-substituted, 9-methyl-and 9, 10-dimethylanthracene) and generated acid by decomposing teemselves. The quantum yields of photobleaching of the anthracenes($\Phi$-AH) and acid generatiion (øacid) by the onium borates were the same order as those of the corresponding onium salts in aerated solutions (methanol and acetoitrile) and in argon(Ar) saturated acetonitrile. However, in the photolysis of the iodonium borates 1a in Ar saturated MeOH , øacid was much higher than the corresponding ø-AH. The acid generated by the photolysis of the onium borates initiated cationic polymerization of an epoxy monomer. The values of both rate of polymerization (Rp) and degree of conversion on the photopolymerization for the iodonium borated 1a were higher than those of the sulfoium borate 2a. In the photopolymerization for the iodonium borate 1a, both the Rp value and the degree of conversinio increased upon the addition of glycerol as a hydrogen donor. It is suggested that the increase of both values may be caused with the increase of øacid by addition of glycerol.
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Lee, Mun-Hag;Kim, Sung-Bin;Lee, Tae-Hoon;Park, Seong-Soo;Son, Se-Mo
- Journal of the Korean Graphic Arts Communication Society
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- v.21 no.2
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- pp.55-65
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- 2003
A novel evaluation method is investigated for UV curing process in printing system. The method is based on the measurement of conducivity change by the photopolymerization of UV curable inks and paints. It is found that the decrease of conductivity is caused by photopolymerization of epoxy monomer during UV curing process of ink film and the by the rate of UV curing. It is possible to make the dynamical evaluation the curing rate of UV curable ink in curing process by this method.
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Sung, A-Young
- Journal of Korean Ophthalmic Optics Society
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- v.6 no.2
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- pp.145-148
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- 2001
The bulk photopolymerization of 2-hydrxyethylmethacrylate(HDMA) with phenylsilane was perforemed to produce poly(HEMA)s containing phenylsilyl moiety presumably as an end group. This result, are the same as that of thermal polymerization. It was found that while the polymerization yields and intrinsic viscosities decreased, the TGA residue yields and the relative intensities of SiH IR stretching bands increased with increasing molar ratio of phenylsilane over HEMA. The phenylsilane seemed to significantly influence on the photopolymerization as both chain initiation and chain transfer agents.
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Yokoyama, Shiyoshi;Nakahama, Tatsuo;Miki, Hideki
- Proceedings of the Polymer Society of Korea Conference
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- 2006.10a
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- pp.231-231
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- 2006
We fabricated a polymer sub-microstructure for optical device application by two-photon-induced laser lithography technique. Polymer pattern could be minimized as small as ${\sim}100\;nm$. The photopolymerization resin contains laser-dye, thus promising a high level of the optical gain. We utilized the lithography technique to the photonic crystal application, where the template of the two-dimensional photonic crystal was modified by polymer gain medium as defect-shape and line-shape orientations. Photonic band gap effect from polymer-doped photonic crystals is expected to exploit the application such as organic solid-state laser device.
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