Patent GB-713233-A (GB)
Title: Improvements in or relating to polymeric organosilicon compounds and compositions containing them
Filed: 1952-06-30
Abstract: Non-resinous organosilicon polymers are stabilised and rendered rust-inhibiting by the addition of at least 0.01 per cent. by weight of the polymer of one or more tin compounds of the formula RxSnZy, where R is a monovalent hydrocarbon radical, Z is an acyloxy radical, x and y have values from 0 to 4, and the sum of x + y is 2 or 4. Suitable organosilicon polymers contain an average of 1.9 to 3.0 organic groups per silicon atom and include organopolysiloxanes, methylene linked organosilicon polymers, as described in Specification 624,550, phenylene linked organosilicon polymers, as described in Specification 669,178, [Group IV (b)], and polymers containing siloxane and methylene linkages, as described in Specifications 621,009, [Group IV (b)], 632,563 and 671,140.  Tin compounds specified are dibutyl tin-diacetate, -dilaurate and -dimaleate, stannous-acetate and -2-ethyl hexoate, tetrabutyl-, tetraphenyl-, tetralauryl-, dibutyldiphenyl-, methyltributyl-, diethyl-and ditolyl-tin.  The stabilised polymers are used as dielectrics, lubricants, hydraulic liquids, protective coatings, and in grease and polishing compositions.  The polishing compositions of emulsion, solvent-solution, solventsus-pension or paste type, comprise (1) 0.5 to 15 per cent. (by weight) of hydrocarbon-soluble non-resinous organosilicon polymer(s), (2) .00005 to 0.15 per cent. of the tin compound, (3). 0 to 10 per cent. of a water-insoluble organic polishing wax, (4) 10 to 90 per cent. of a hydrocarbon solvent boiling between 100 DEG  and 300 DEG C., (5) 0 to 20 per cent. of finely divided silica having a particle size less than 10 microns, (6) 0 to 6 per cent. of an emuslifying agent, (7) 0 to 3 per cent. of aluminium mono- or di-stearate, and (8) 0 to 87.5 per cent. of water.  Specified ingredients of the polishes are solvents: petroleum and coal tar hydrocarbons; waxes: carnauba, candelilla, paraffin, microcrystalline ceresin, montan and synthetic waxes; silicas: diatomacesous earth and Tripoli silica; emulsifying agents: morpholine oleate and stearate, n-dodecyl-, n-octadecyl-, and n-octadecadienyl-amine acetates, hexamethylene glycol mono-oleate and aryl polyether alcohols.  In examples (1 to 7), various tin compounds are dissolved liquid trimethyl-siloxy end-blocked dimethyl polysiloxane and other organosilicon polymers; (8) carbon black is mixed with a methyl phenyl siloxane copolymer and dibutyl tin dilaurate to form a grease; (9, 10) polishes are composed of trimethylsiloxy end-blocked dimethyl polysiloxane, dibutyl tin dilaurate and carnauba wax, naphthol mineral spirits and diatomaceous earth, or stoddard solvent, kerosene, oleic acid, morpholine, water and silica.ALSO:A lubricating liquid or grease comprises one or more non-resinous organosilicon polymers which have been stabilised and rendered rust-inhibiting by the addition of at least 0.01 per cent. by weight of the polymer(s) of one or more tin compounds of the formula Rx SnZy, where R is a monovalent hydrocarbon radical, Z is an acryloxy radical x and y have values from 0 to 4, and the sum of x+y is 2 or 4 (see Group IV (a)).  In example 8 a grease is made by mixing carbon black with dibutyl tin dilaurate and a non-resinous methyl phenyl siloxane copolymer.