• Applied Chemistry for Engineering
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• v.1 no.1
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• pp.1-10
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• 1990

Polysilane derivatives are attracting considerable attention as a new class of material since 1980. The preparation methods of low molecular weight, cyclic, and high molecular weight polysilane derivatives are described, and also photochemistry characteristics for silicon-silicon single bond and for the nature of the substituent on silicon backbone are discussed. Polysilanes may be used as a precursors to silicon carbide fiber, as photoresist in microelectronics, as photoconductor, and as photoinitatior for free radical polymerization.

• Analytical Science and Technology
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• v.25 no.6
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• pp.345-349
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• 2012

Polysilane black powders were synthesized by sonochemical methods from silicon tetrachloride with sodium metal with 37.0% yield. Those black powder materials were found to have fibrous or irregular shapes with round surface. It was found that thermal behaviors of those polysilane black powders were similar to that of hydropolysilanes which was reported earlier. After thermal treatment, black polysilicon was obtained with 57.1% residue yield, and those fibrous or irregular shapes with round surface were intact but lots of small cavities were formed indicating porous structure, and found to be an amorphous state from XRD analysis.

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2443-2445
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• 2009

• Journal of the Korean Chemical Society
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• v.41 no.9
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• pp.502-517
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• 1997

This review deals with (1) the catalytic systems and mechanisms for the dehydropolymerization of silanes to polysilanes, (2) the dehydropolymerization of versatile silanes, (3) the preparation of polysilane derivatives, and (4) the applications of catalytic dehydropolymerizing systems to ceramics. The efforts to maximize the catalytic efficiency of group 4 metallocenes were introduced. Finally, the future of this dehydropolymerizing techniques of silanes was foreseen.

• Journal of the Korean Chemical Society
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• v.39 no.10
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• pp.783-788
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• 1995

Silyltriflates are obtained by reaction of the corresponding phenyl derivatives with CF3SO3H. The reaction of silyltriflate with allylmagnesium bromide produced the allylated silane derivatives R2SiHCH2CH=CH2 (R=Me, Ph). They are formed under mild condition with Pt catalysis to polycarbosilane. The cleavage of silicon-phenyl bonds of polysilane by CF3SO3H leads to triflate derivatives of polycarbosilane.

• Journal of Integrative Natural Science
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• v.3 no.2
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• pp.61-71
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• 2010

Hydrosilanes possessing reactive Si-H bond are used in synthesizing various types of polysilanes by dehydrocoupling under the influence of various organometallic promoters. Catalytic Si-Si/Si-O coupling of hydrosilanes with hydrosilanes, alcohols, and lactones to silicon-based polymers are described in this article as selective examples of our recent research developments. These silicon-containing polymers can be used as a precursor to prepare useful functional materials for fabricating electronic devices.

• Bulletin of the Korean Chemical Society
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• v.16 no.1
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• pp.30-33
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• 1995

UV photolysis of the titled polysilane (Me3Si)3SiMe (I) in the presence of a trapping agent of 2-propenol has been performed to investigate the interaction of short-lived silicon species formed from the photolysis of I with 2-propenol. Product studies show that the Me(Me3Si)Si: (II) and (Me3Si)3Si${\cdot}$(III) are primarily formed as the major reactive species which saturate their valencies via O-H insertion and H-abstraction, respectively. Some products are unstable toward further secondary reaction such as photodissociation and intermolecular reaction. The PM3 semiempirical calculations are performed to deduce the energetics of the photoinduced chemical reactions of I with the substrate.

• Bulletin of the Korean Chemical Society
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• v.16 no.1
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• pp.58-62
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• 1995

Substituted 3-phenyl-1-silabutanes such as 3-phenyl-1-silabutane (1), 3-(2,5-dimethylphenyl)-1-silabutane (2), 3-(p-chlorotolyl)-1-silabutane (3), and 3-naphthyl-1-silabutane (4) were prepared in 62-96% yield by reduction of the corresponding substituted 3-phenyl-1,1-dichloro-1-silabutanes with LiAlH4. The dehydrogenative polymerization of the monomer silanes was carried out with Cp2MCl2/Red-Al (M=Ti, Hf) catalyst system. The molecular weight of the polymers produced ranged from 700 to 1300 (vs polystyrene) with degree of polymerization (DP) of 5 through 16 and with polydispersity index (PDI)=1.1-2.1. The dehydrogenative polymerization of the monomer silanes with Cp2TiCl2/Red-Al catalyst system occurred at a faster rate and produced somewhat higher molecular weights of polysilane than that with Cp2HfCl2/Red-Al catalyst system.

• Bulletin of the Korean Chemical Society
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• v.17 no.5
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• pp.443-447
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• 1996

Several polysilanes with sterically bulky substituents such as poly(2-phenylpropyl)(n-hexyl)silane were prepared by Wurtz-type coupling. The polysilane products were mixtures of low-molecular-weight polymers (&bar{M};w~103) as major and high-molecular-weight polymers (&bar{M};w~106) as minor. Overall yields for polysilanes were in the range of 81-99%. λmax of liquid low MW polymers appeared at around 280 nm. Formations of solid high MW polymers were decreased by a longer reaction time and increased steric bulkiness of substituents. High MW polymers with λmax at 327 nm except crosslinked polymers were soluble in common organic solvents and found to be light sensitive. Crosslinked high MW polymer gave 21% TGA ceramic yield, compared with linear high polymer giving zero ceramic yield.

• Analytical Science and Technology
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• v.19 no.6
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• pp.504-511
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• 2006

Polysilanes with organic substituents such as methyl and phenyl were synthesized by Wurtz dechlorination-condensation reactions using ultrasonic from organochlorosilanes. The yields were compared with the results of thermal dechlorination-condensation reactions. Properties such as thermogravimetric analysis and photoreactivity were investigated for the possibility of applications.