- Method for preparing methyltris(trimethylsiloxy)silane
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The invention provides a method for preparing methyltris(trimethylsiloxy)silane. The method comprises the steps that hexamethyldisiloxane and alcohol are mixed, then oxygen-containing linear phosphazene chloride is dripped in the mixture, and stirring is
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Paragraph 0039-0048
(2019/10/01)
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- SUPER ACIDS AND BASES AS DEHYDROCONDENSATION CATALYSTS
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There is provided herein a composition which contains hydride-functionalized siloxane or silane, a hydroxyl-containing compound that does not contain silicon, and a catalytically-effective amount of super acid or super base catalyst selected from the group consisting of a triaza-containing compound which contains only carbon, nitrogen and hydrogen atoms, an atrane compound, a linear or branched compound containing a sulfonyl group and a fluoro group, and combinations thereof. There is also provided a process of making such a composition.
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Paragraph 0076; 0077; 0081
(2016/12/26)
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- Method for producing polyimidesiloxane
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PROBLEM TO BE SOLVED: To provide a method for synthesizing siloxanes at will in good yield while maintaining high structural controllability, which can be applied to substrates having various substituents.SOLUTION: The method comprises reacting benzyloxysilanes and silicon halides in the absence of hydrogen using a catalyst comprising a transition metal or a compound thereof, preferably a metal of group 9 or group 10 of the periodic table or a compound thereof. Thereby, corresponding siloxanes can be produced safely and simply in high yield under a mild reaction condition accompanied by elimination of a benzyl halide. Especially, by using an active carbon-supported catalyst as a heterogeneous catalyst, the target siloxanes can be separated easily.
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Paragraph 0041
(2018/10/16)
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- Pd/C-catalyzed cross-coupling reaction of benzyloxysilanes with halosilanes for selective synthesis of unsymmetrical siloxanes
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A new protocol for the nonhydrolytic synthesis of unsymmetrical siloxanes has been developed. The cross-coupling reaction of benzyloxysilanes with halosilanes catalyzed by Pd/C afforded various unsymmetrical siloxanes with co-production of benzyl halides. the Partner Organisations 2014.
- Igarashi, Masayasu,Kubo, Keiko,Matsumoto, Tomohiro,Sato, Kazuhiko,Ando, Wataru,Shimada, Shigeru
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p. 19099 - 19102
(2014/05/20)
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- Preparation of branched siloxane
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By reacting a branched siloxane compound of formula (2) containing compounds of formula (1) as an impurity with a disiloxane compound of formula (3) in the presence of an acid compound, there is prepared a branched siloxane of formula (2) containing a reduced level of compounds of formula (1).R1?nSi(OSiR2?3)3-n(OR3)R1?nSi(OSiR2?3)4-nR2?3SiOSiR2?3 R1 is a monovalent hydrocarbon group, R2 and R3 are H or monovalent hydrocarbon groups, and n is 0 or 1.
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Page/Page column 10-11
(2010/02/10)
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- Cosmetic composition comprising a volatile fatty phase
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The invention relates to a composition comprising, in a physiologically acceptable medium, a volatile silicone fatty phase comprising at least one non-cyclic volatile silicone oil, wherein the volatile silicone fatty phase has an evaporation profile such that the mass of the at least one volatile silicone oil evaporated after 30 minutes is from 2 mg/cm2 to 9 mg/cm2. The invention also relates to making up and caring for human keratin materials using the inventive compositions.
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- Preparation of branched tetrasiloxane
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A branched tetrasiloxane is prepared by preforming a liquid mixture of a disiloxane compound, an alcohol and an acid catalyst, adding a trialkoxysilane compound to the mixture for reaction, and adding water to the reaction mixture for co-hydrolysis, there
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Page column 7-9
(2010/02/09)
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- PREPARATION OF LOW MOLECULAR WEIGHT BRANCHED SILOXANES
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A low molecular weight branched siloxane, typically methyltris(trimethylsiloxy)silane is effectively prepared in high yields by reacting a trichlorosilane, typically methyltrichlorosilane with a disiloxane, typically hexamethyldisiloxane in the presence o
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- COSMETICS
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The present invention is a cosmetic, characterized in that it contains an organopolysiloxane having the following general formula:{(CH3)3SiO}3SiCH3 The cosmetic demonstrates excellent volatility and feel when us
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- Generation and capture of methyl(vinyl)silanone
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Methyl(vinyl)dichlorosilane reacts with DMSO in the presence of hexamethyldisiloxane to give the corresponding linear oligosiloxanes of the general formula Me3Si(OSiMeVin)nOSiMe3 (n = 1-6) as well as MeSi(OSiMe3)3 and Me3Si(MeOSiVin)mOSi(OSiMe3)(Me)OSiMe 3 (m = 1-2). The same reaction in the presence of chlorotrimethylsilane results in oligomers of the general formula Me3Si(OSiMeVin)nCl (n = 1-3). A possible scheme of their formation is discussed.
- Basenko,Gebel,Voronkov,Klyba,Mirskov
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p. 1571 - 1573
(2007/10/03)
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- Siloxane basicity toward strong acid in nonpolar solution
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The relative basicities of ten siloxanes and an ether were studied in benzene by determining from visible spectroscopic measurements the thermodynamic constants for the competition between the substrate and a reference base (4-chloro-2-nitroaniline) for acid (trifluoromethanesulfonic acid): RB-HA + S ? RB + S·HA. The Keq values were considered as a measure of basicity with the following order established and explained by inductive effects in the protonated species: permethyl linear siloxanes (Me3Si(OSiMe2)nOSiMe3, n = 0-3) > dibutyl ether > HMe2SiOSiMe2H > branched siloxanes ((Me3SiO)3SiMe, (Me3SiO)4Si) > cyclic siloxanes ((Me2SiO)n, n = 3-5). The ΔH and ΔS values were positive and increased with higher basicity; this behavior was attributed to differential solvation of ion pairs.
- Shepherd, Brian D.
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p. 5581 - 5583
(2007/10/02)
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- MUTUAL EFFECT OF SOLUTIONS OF SALTS AND HCl ON COHYDROLYSIS OF METHYLCHLOROSILANES
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In hydrolytic polycondensation of Me2SiCl2, the combined effect of salts and HCl causes a decrease in the yield of 4, and this effect increases with an increase in the binding strength of the water with the salt in hydrate complexes and the concentration of HCl.The combined effect of salts and HCl on the composition of the products of the reaction in hydrolytic copolycondensation of Me2SiCl2 with Me3SiCl and MeSiCl3 with Me3SiCl increases with an increase in the degree of binding of water in hydrate complexes, caused by competition in the formation of hydrate complexes between the salt and HCl.
- Kopylov, V. M.,Agashkov, S. P.,Sunkovich, G. V.,Prikhod'ko, P. L.
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p. 692 - 697
(2007/10/02)
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- Treatment of alkyltriethoxysilanes with Amberlyst 15 cation-exchange resin in the presence of hexamethyldisiloxane
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Methyltriethoxysilane and ethyltriethoxysilane were treated with Amberlyst 15 cation-exchange resin in the presence of hexamethyldisiloxane at 40 deg C.The reaction involves partial or full replacement of the ethoxyl group by trimethylsiloxyl to give RSi(OEt)n(OSiMe3)3-n (n=0, 1, 2).The degree of substitution depends mainly on the ratio in which hexamethyldisiloxane and alkyltriethoxysilane are mixed.The nature of alkyl group in an alkyltriethoxysilane had little effect on the degree of substitution at a given mixing ratio.
- Hasegawa, Isao,Sakka, Sumio
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