Patent GB-624363-A (GB)
Title: Improvements in or relating to organo-silicon compounds
IPC: C08G77/20
Filed: 1946-03-08
Abstract: An allyl silicon resin is obtained by hydrolysing an organo-silicon compound of the general formula (H2C=CH-CH2)x(CH3)zSiY[4 - (x+2)], wherein x and z are numbers from 1 to 2, the sum of x and z not exceeding 3 and Y represents chlorine or an ethoxy group, to form the corresponding silicol which is then dehydrated and condensed to form the corresponding silicone.  Polymerization through the unsaturated allyl group may also take place.  The dehydration is preferably carried out in the presence of a dehydrating agent, e.g. boric acid esters such as methyl borate, metal halides, the oxides and halides of phosphorus, sulphuric and hydrochloric acids.  The allyl silicones may be added to alkyl or aryl silicones.  Interpolymers are obtained by carrying out the hydrolysis, condensation and dehydration in the presence of an organo silicon compound of the general formula RxSiY4-x, wherein R is a hydrocarbon group which will not undergo a vinyl type polymerization, x has a value from 1 to 3 and Y is a halide or an ethoxy group, or by dehydrating and condensing a mixture of the corresponding silicols, or by mixing the corresponding silicones or solutions thereof when they are liquids due to a low degree of polymerization and heating.  The condensation may be continued only until a hydrocarbon soluble silicone is obtained, and the silicone may then be dissolved in a hydrocarbon such as toluene, or may be dispersed or emulsified in a volatile liquid carrier such as water, e.g. with the aid of ammonia, or a dispersing agent such as a sodium alkyl sulphonate ester, or a hydrolysed polyvinyl ester and a simple alcohol such as ethyl alcohol.  Finely-divided inorganic materials may be added to the silicone polymers or interpolymers, e.g. silica flour, bentonite, glass powders, calcium fluoride, ceramic powders, graphite, anthracite, coal or petroleum coke.  In examples, allyl-methyl-silicon diethoxide is refluxed with sulphuric acid to yield an oily silicone, and a mixture of dimethyl silicon diethoxide and allyl dimethyl silicon ethoxide is treated with sulphuric acid in the presence of toluene to yield an oily liquid which may be further polymerized by heating in the presence of tertiary-butyl perbenzoate and a chromium chelate compound.  The Specification mentions that allylmethyl silicon ethoxides or mixtures thereof can be polymerized directly to form resinous bodies by the application of heat in the presence of a catalyst such as organic and inorganic peroxides, inorganic acids or inorganic halides, e.g. allylmethyl silicon diethoxide may be heated with benzoyl peroxide. Specifications 624,361 and 624,364 are referred to.ALSO:Organo-silicon compounds of the general formula (H2C-CH=CH2)x(CH3)z SiY[4-(x+z)], wherein x and z are numbers from 1 to 2, the sum of x and z not exceeding 3 and Y represents chlorine or an ethoxyl radical, are prepared by treating ethyl orthosilicate or silicon tetrachloride with a Grignard reagent to substitute the desired allyl and methyl groups for the chlorine or ethoxy radicals. The products may be hydrolysed to the corresponding silicols and may then be dehydrated and condensed to yield a silicone.  Silicone interpolymers may be obtained by hydrolysing a mixture of the above silicon compounds with silicon compounds of the general formula RnSiY4-n, wherein R represents a saturated hydrocarbon group, Y is a halide or ethoxy radical and n is a number from 1 to 3, and dehydrating and condensing the resulting mixture of silicols.  By saturated hydrocarbon group is meant a hydrocarbon group which will not undergo a vinyl type of polymerisation, e.g. alkyl or phenyl radicals.  In example: (1) allyl silicon triethoxide and diallyl silicon diethoxide are prepared by a Grignard reaction and by subsequent treatment with methyl magnesium chloride, allylmethyl silicon diethoxide and diallylmethyl silicon ethoxide are prepared; (2) methyl silicon triethoxide is prepared by a Grignard reaction and is then reacted with allyl magnesium chloride to yield allylmethyl silicon diethoxide; (3) allyldimethyl silicon ethoxide is prepared by reacting allylsilicon triethoxide and methyl magnesium bromide. Specifications 624,361 and 624,364 are referred to.  Allyltrimethyl silicon is prepared by reacting methyl magnesium bromide and allyl silicon triethoxide.  The Specification as open to inspection under Sect. 91 refers to the preparation of organo silicon compounds of the formula <FORM:0624363/IV (b)/1> wherein x is a number from 1 to 2, z is a number from 1 to 3, the sum of x and z being 4.  This subject-matter does not appear in the Specification as accepted.ALSO:Plastic compositions comprise mica flakes or inorganic fibrous materials such as asbestos or cloth or glass fibres bound together with an allyl silicone as obtained by hydrolysing and condensing a compound of the general formula (H2C=CH-CH2)x(CH3) SiY[4-(x+z)], wherein x and z are numbers from 1 to 2, the sum of x and z not exceeding 3 and y represents chlorine or an ethoxy group, or with an allyl silicone interpolymer as obtained by carrying out the above hydrolysis and condensation in the presence of a silicon compound of the general formula Rx Si Y4-x, wherein R is a hydrocarbon group which will not undergo a vinyl type polymerisation, x has a value from 1 to 3 and Y is a halide or an ethoxy group. Specifications 624,361 and 624,364 are referred to.