• Journal of Integrative Natural Science
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• v.2 no.1
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• pp.1-12
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• 2009

This miniaccount presents the selective examples of our recent discoveries in the photopolymerization of vinyl monomers using the organic initiators such as hydrosilanes, poly(hydroarylsilane)s, benzoin silyl ethers, and thianthrene cation radical. In the photopolymerization of vinyl monomers with silanes polysilanes, while the polymerization yields and polymer molecular weights of the poly(MMA)s containing the silyl moieties decreased, the TGA residue yields and intensities of SiH stretching IR bands increased as the mole ratio of the silanes over MMA increased. The hydroarylsilane and poly(hydroarylsilane) seemed to influence strongly on the photopolymerizaiton of olefinic monomers as both chain initiation and chain transfer agents. For the photohomopolymerization and photocopolymerization of MA and AA, the similar trends were observed. Benzoin silyl ethers and thianthrene cation radical also exhibit the photoinitiating ability in the photopolymerization of MMA.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.87-90
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• 2000

Poly(HEMA)s have been used as the optometric material for the preparation of soft contact lens. The bulk thermal polymerization of 2-hydroxyethyl methacrylate (HEMA) with various hydrosilanes such as $phSiH_3$, $phMeSiH_2$, and $ph2SiH_2$ were performed to produce poly(HEMA)s containing phenylsilyl end moeity. It was found for thermal polymerization that while the polymerization yield and polymer molcular weights decreased as the relative phenylsilane concentration increases, the TGA residue yields and the relative intensities of SiH IR stretching bands increased as the relative hydrosilane concentration increases over HEMA. The polymerization yield, molecular weight, and TGA residue for the thermal polymerization were higher than those for the photo polymerization. Thus, the hydrosilanes significantly influence on the polymerization as both chain-initiation and chain-transfer agents.

• Journal of Integrative Natural Science
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• v.2 no.1
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• pp.18-23
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• 2009

This minireview provides the chosen examples of our recent discoveries in the polymerization of hydrosilanes, dihydrosilole, lactones, and vinyl derivatives using various catalysts. Hydrosilanes and lactones copolymerize to give poly(lactone-co-silane)s with $Cp_2MCl_2$/Red-Al (M = Ti, Zr, Hf) catalyst. Hydrosilanes (including dihydrosilole) reduce noble metal complexes (e.g., $AgNO_3$, $Ag_2SO_4$, $HAuCl_4$, $H_2PtCl_6$) to give nanoparticles along with silicon polymers such as polysilanes, polysilole, polysiloxanes (and silicas) depending on the reaction conditions. Interestingly, phenylsilane dehydrocoupled to polyphenylsilane in the inert nitrogen atmosphere while phenylsilane dehydrocoupled to silica in the ambient air atmosphere. $Cp_2M/CX_4$ (M = Fe, Co, Ni; X = Cl, Br, I) combination initiate the polymerization of vinyl monomers. In the photopolymerization of vinyl monomers using $Cp_2M/CCl_4$ (M = Fe, Co, Ni), the photopolymerization of MMA initiated by $Cp_2M/CCl_4$ (M = Fe, Co, Ni) shows while the polymerization yield decreases in the order $Cp_2Fe$ > $Cp_2Ni$ > $Cp_2Co$, the molecular weight decreases in the order $Cp_2Co$ > $Cp_2Ni$ > $Cp_2Fe$. For the photohomopolymerization and photocopolymerization of MA and AA, the similar trends were observed. The photopolymerizations are not living. Many exciting possibilities remain to be examined and some of them are demonstrated in the body of the minireview.