Silicon monomers

Synthesis of Silicone Monomers and Intermediates. Another important reaction for the formation of Si—C bonds, in addition to the direct process and the Grignard reaction, is hydrosdylation (eq. 3), which is used for the formation of monomers for producing a wide range of organomodified sihcones and for cross-linking sihcone polymers (8,52—58). Formation of ether and ester bonds at sihcon is important for the manufacture of curable sihcone materials. Alcoholysis of the Si—Cl bond (eq. 4) is a method for forming silyl ethers. HCl removal is typically accomphshed by the addition of tertiary amines or by using NaOR in place of R OH to form NaCl. 

Si NMR spectroscopy reveals that the silicon monomers and dimers start to bind into higher silicon oligomers at the very beginning of the Ti-Beta synthesis procedure. After... 

Silicone membranes, flow through, 15 722— 723. See also Membrane processes Silicone monomers, synthesis of,... 

This is where all polyorganosiloxanes (silicones) start. The methods of the preparation of silicone monomers and their precursors have not changed significantly since the beginning of silicone technology. Functional silanes are synthesized by one of the following methods 3... 

A. D. Petrov, B. F. Mironov. V. A. Ponomarenko and E. A. Charrystov, Synthesis of Organo-silicon Monomers p. 186. English translation. Hey wood, London (1964). 

In 1863 Friedel and Crafts were the first to use metalorganic compounds to synthesise silicone monomers. Industiy focused on organomagnesium synthesis (the Grignard technique), in which alkyl- or arylhalogenide interacts with metallic magnesium to form organomagnesium compounds ... 

Foreign references contain no information about the use of high-temperature condensation for industrial production of silicone monomers thus, our country has a priority (Corresponding Member of the USSR Academy of Sciences A.D.Petrov, Corresponding Member of the RF Academy of Sciences E.A.Chemyshev) in the development of scientific foundations and industrial implementation of high-temperature condensation to obtain silicone monomers with aromatic radicals, unsaturated groups or mixed radicals attached to the silicon atom. 

The synthesis of silicone monomers based on the interaction of hy-dridechlorosilanes with alkyl-, alkenyl- or arylchlorides, is a convenient technique, which has recently found a wide application. 

Similarly to vinyltrichlorosilane, vinylmethyldichlorosilane and methylthyenildichlorosilane, HTC is used to produce allyltrichlorosilane, thyenil-trichlorosilane, vinylethyldichlorosilane, allylmethyldichlorosilane, vinyl-phenyldichlorosilane and other chlorine-containing silicone monomers with organic radicals attached to the silicon atom. Table 7 lists the physicochemical properties of some chlorine derivatives of unsaturated silicone compounds. 

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