GB1025663A - Improvements in and relating to organosiloxane compositions - Google Patents

Abstract

A composition which can be heat cured to a water repellant form comprises a solution in an organic solvent of an organosiloxane polymer of unit formula <FORM:1025663/C3/1> and an aluminium compound of the formula Al(O-CH.R1-CH2R1)3, or an organic solvent-soluble partial hydrolysate thereof, in which formulae each R and R1 is a monovalent hydrocarbon radical, R11 is H or a monovalent hydrocarbon radical, each n is 0 to 3 averaging 0.8 to 2.8, each m is 0 to 3 averaging 0 to 1.2, each p is 0 to 1 and the average of m+n+p is from 1 to 2.8. Specified solvents are hydrocarbons fluid at 18 DEG C. and boiling below 150 DEG C., e.g. petroleum ethers, benzine, benzene, toluene or xylene, and halohydrocarbons, e.g. carbon tetrachloride, trichloroethylene, perchloroethylene or methylene chloride. The halo-hydrocarbons should not be used with siloxanes containing the -SiH grouping except for diluting concentrates immediately prior to use. The composition may also contain a compound which forms chelates with the aluminium compound, numerous compounds with conjugate keto groups being listed for this purpose; alkylmono-carboxylic acids, e.g. acetic, or hydroxycarboxylic acids, e.g. lactic. The solutions may be used, optionally in conjunction with other resins such as urea or melamine-formaldehyde condensates and vinyl acetate or acrylonitrile polymers, to render various articles water-repellant, especially paper, textiles and leather. In the examples the polysiloxanes are trimethylsiloxy or hydroxy end-blocked dimethylpolysiloxanes or methyl hydrogen polysiloxanes and mixtures thereof.ALSO:Compositions for water-proofing various articles, especially paper, textiles and leather, comprise a solution in an organic solvent of an organopolysiloxane of unit formula <FORM:1025663/D1-D2/1> and an aluminium compound Al(O-CH.R1.CH2R1)3 or an organic solvent-soluble partial condensate thereof. Each R and R1 is a monovalent hydrocarbon radical, R11 is H or a monovalent hydrocarbon radical, each n is 0 to 3 averaging 0.8 to 2.8, each m is 0 to 3 averaging 0 to 1.2, each p is 0 or 1 and the average of m + n + p is 1 to 2.8. Specified solvents are hydrocarbons fluid at 18 DEG C. and boiling below 150 DEG C. e.g. petroleum ethers, benzine, benzene, toluene or xylene; and halohydrocarbons, e.g. carbon tetrachloride, methylene dichloride, or tri- or per-chloroethylene, which should not be used with -SiH-containing siloxanes except for diluting concentrates immediately prior to use. The composition may also contain a compound forming chelates with the aluminium compound, various compounds with conjugate keto groups being exemplified; alkylmonocarboxylic acids, e.g. acetic; hydroxycarboxylic acids, e.g. lactic; and other resins, e.g. urea- or melamine-formaldehyde condensates or vinyl acetate or acrylonitrile polymers. Natural and synthetic textile materials which may be treated are exemplified. The materials may be treated with the solution by spraying, rolling, padding or dipping and the composition cures to the water-repeller form in a few days at room temperature or 1 to 30 minutes at 100 to 180 DEG C.