Patent GB-691628-A (GB)
Title: Improvements in or relating to plasticisers comprising organosilicon compounds
IPC: C07F7/18
Filed: 1951-01-18
Abstract: A synthetic resin composition comprises a hydrocarbon polymer containing aliphatically-combined chlorine as the principal constituent and from 0.5 to 15 per cent, based on the weight of the polymer, of one or more compounds of the general formula <FORM:0691628/IV (a)/1> where R represents a tert.-alkyl radical having 4 or 5 carbon atoms and n is from 1 to 5 inclusive.  Polymers mentioned are polyvinylidene chloride, polyvinyl chloride and chloroprene. Phenylmethylsilane is mentioned as a plasticizer. Siloxanes of the above general formula are prepared by dissolving phenylmethyldichlorosilane in pyridine in an amount excess of that required to combine with all the hydrogen chloride produced from the silane, and then adding tert.-butyl or amyl alcohol in a proportion of at least two mols. per mol. of silane, or by partially hydrolysing phenylmethyldichlorosilane and condensing to form siloxanes having from 1 to 5 silicon atoms per molecule and then dissolving the phenylmethylsilicon oxychlorides thus produced in pyridine and reacting with the required alcohol as above, or by reacting phenylmethylsiloxane diols with the required tert.-alkyl chloride, or by an alcohol interchange by reacting phenylmethylethoxysiloxanes and the required tert.-alcohol.  In example (1) a mixture of siloxanes of the above general formula is prepared by reacting phenylmethyldichlorosilane in pyridine with t.-butyl alcohol.  In example (2), phenylmethyldichlorosilane is hydrolysed with sufficient water to react with three-quarters of the chlorine present, and the linear siloxanes having an average of approximately 4 silicon atoms are then reacted with t.-amyl alcohol in the presence of pyridine to form a mixture of siloxanes of the above general formula having an average of approximately 4 silicon atoms per molecule.ALSO:The invention comprises organo-silicon compounds of the general formula <FORM:0691628/IV (b)/1> wherein R represents a tertiary alkyl radical having from 4 to 5 carbon atoms and n has a value from 1 to 5, and mixtures thereof. The compounds may be prepared by dissolving phenylmethyldichlorosilane in pyridine in an amount excess of that required to combine with all the hydrogen chloride produced from the chlorine in the silane, and then adding tert.-butyl- or tert.-amyl alcohol in a proportion of at least two mols. per mol. of silane, or by partially hydrolysing phenylmethyldichlorosilane and condensing to form siloxanes having from one to five silicon atoms per molecule and then dissolving the phenylmethylsilicon oxychlorides thus produced in pyridine and reacting with the required alcohol as above, or by reacting phenylmethylsiloxane diols with the required tert.-alkyl chloride, or by an alcohol interchange from the reaction of phenylmethylethoxysiloxanes and the required tert.-alcohol.  In example (1), a mixture of siloxanes of the above general formula is prepared by the reaction of phenylmethyldichlorosilane, pyridine and t.-butyl alcohol, and phenylmethyl-di-t.-butoxysilane is isolated by distillation.  In example (2), phenylmethyldichlorosilane is hydrolysed with water to hydrolyse three-quarters of the chlorine present; and the linear siloxanes having an average of approximately four silicon atoms per molecule are then reacted with t.-amyl alcohol and pyridine to form a mixture of siloxanes of the above general formula having an average of approximately four silicon atoms per molecule.ALSO:Hydrochlorinated rubber is stabilized with one or more silanes of the general formula:- <FORM:0691628/V/1> wherein R represents a tert.-alkyl radical having 4 or 5 carbon atoms and n is from 1 to 5 inclusive.