Patent GB-804992-A (GB)
Title: Improvements in or relating to oxygen-silicon containing compositions, preparation and use thereof
IPC: C09C1/30
Filed: 1955-05-09
Abstract: <PICT:0804992/III/1> Solid silicon monoxide, containing a substantial amount of fibres having a ratio of width to length 1 : 10 to 1 : 50, an average particle length of 50 to 600 mm , and a surface area 60 to 200 sq. m./grm. and containing 1 to 8 per cent nitrogen, and exhibiting lines of silicon and a halo of amorphous silica on X-ray diffraction, is prepared by contacting silicon monoxide gas with an inert gas containing 0.5-9 vol. per cent gaseous amine or ammonia under substantially non-turbulent conditions, and condensing the silicon monoxide gas in the inert amine- or ammonia-containing gas to a particulate solid.  The silicon monoxide gas is prepared by reducing silica, sand, quartz or mineral silicate with silicon, silicon carbide, or carbon, e.g. anthracite, carbon black, coal or petroleum coke free of volatiles.  A charge of equal mols. silica and carbon is fed by screw or other conveyers to furnace 5 and subjected to arc 2 between electrodes 3, which may be cooled and fed to the furnace as they are consumed.  The mixture of silicon and carbon monoxides produced passes through port 7 into condensing tube 8, where it is mixed with inert gas containing amine or ammonia, flowing through registering ports 11, 12 from chamber 9, with a minimum of turbulence.  The inert gas entering chamber 9 through inlets 10 may be carbon monoxide, nitrogen, argon, helium, or neon, or mixtures thereof, and is mixed with the gas mixture, from the furnace in the ratio 3 : 1 to 15 : 1 ft.3/min., preferably 8 : 1 ft.3/min.  The amine may be alkyl amine, e.g. monoethyl amine, or aryl amine.  The inert gas may alternatively be introduced into the gas mixture from the furnace by an open ring or pipes directly about port 7 to provide a column of gas and lamellar flow.  The mixture of gases passes from tube 8 into collecting chamber 15, where the fibrous silicon monoxide is deposited on screen 17.  Residual gases are withdrawn at 18 and may be recycled to chamber 9 for re-use, after adding sufficient gaseous ammonia or amine to maintain 0.5-9 vol. per cent.  The collector may alternatively be a gaspervious bag or a cyclone, and other hightemperature furnaces, e.g. a resistance furnace, may be used.  The silicon monoxide is used in amount 20-45 per cent as a reinforcing filler for rubbers.  The silicon monoxide may be milled into the composition or mixed with latex, which is coagulated and dried, and the composition may include minor amounts of vulcanizing, accelerator, anti-oxidant, and pigment ingredients, e.g. sulphur, zinc oxide, zinc stearate, titanium dioxide, di-dodecylamine, pine tar, phenyl-p-naphthylamine, 2-mercapto-methylene ammonium penta-methylene dithiocarbamate, and stearic acid.  The composition is vulcanized at 250-300 DEG  F. The rubber may be natural rubber, e.g. caoutchouc, balata, or gutta percha, polychloroprene, polymers of conjugated dienes, e.g. butadiene-1,3, isoprene 2,3- or 1, 4-dimethyl butadiene-1,3, copolymers of such dienes, or containing at least 50 per cent conjugated diene, with isobutylene, methyl- or ethyl-, acrylates or methacrylate, 2-vinyl pyridine, styrene, acrylo- or methacrylo-nitriles, or mixtures of these, or polyacrylic rubber obtained by polymerization of esters of acrylic acid, e.g. methyl-, ethyl-, propyl-, butyl-, or octyl-acrylates, methyl-, ethyl-, or butyl-methacrylates, or methyl ethacrylate, or mixtures thereof, or by copolymerization of acrylic esters with 5-10 per cent chloroethyl vinyl ether, acrylonitrile, vinyl chloride, dichlorodifluoroethylene, or styrene.  The acrylic rubbers may be mixed with 80-20 parts polychloroprene, butadiene-1,3-styrene copolymer, or natural rubber. Example VI describes a uniform mixture of silicon monoxide, natural rubber, zinc oxide, pine tar, phenyl naphthylamine, stearic acid, didodecylamine, and sulphur.  Specifications 804,991 and 804,993, [Group IV (a)], are referred to.ALSO:Solid silicon monoxide, containing a substantial amount of fibres having a ratio of width to length 1 : 10 to 1 : 50, an average particle length of 50 to 600 mm , and a surface area 60 to 200 sq. m./grm. and containing 1 to 8 per cent nitrogen, and exhibiting lines of silicon and a halo of amorphous silica on X-ray diffraction, is prepared by contacting silicon monoxide gas with an inert gas containing 0.5-9 per cent vol. gaseous amine or ammonia under substantially non-turbulent conditions, and condensing the silicon monoxide gas in the inert amine-or ammonia-containing gas to a particulate solid (see Group III) and the particulate solid silicon monoxide is used in amount 20-45 per cent as a reinforcing filler for rubbers.  The silicon monoxide may be milled into the composition or mixed with latex, which is coagulated and dried, and the composition may include minor amounts of vulcanizing, accelerator, anti-oxidant, and pigment ingredients, e.g. sulphur, zinc oxide, zinc stearate, titanium dioxide, di-dodecylamine, pine tar, phenyl-p-naphthylamine, 2-mercapto-benzothiazole, diortho-tolyl guanidine, N-pentamethylene ammonium penta-methylene dithiocarbamate, and stearic acid.  The composition is vulcanized at 250-300 DEG  F.  The rubber may be natural rubber, e.g. caoutchouc, balata, or gutta percha, polychloroprene, polymers of conjugated dienes, e.g. butadiene-1,3, isoprene 2, 3 or 1, 4-dimethyl butadiene-1,3, copolymers of such dienes, or containing at least 50 per cent conjugated diene, with isobutylene, methyl- or ethyl-, acrylates or methacrylates, 2-vinyl pyridine, styrene, acrylo- or methacrylo-nitriles, or mixtures of these, or polyacrylic rubber obtained by polymerization of esters of acrylic acid, e.g. methyl-, ethyl-, propyl-, butyl- or octyl-acrylates, methyl-, ethyl -, or butyl - methacrylates, or methyl ethacrylate, or mixtures thereof, or by copolymerization of acrylic esters with 5-10 per cent chloroethyl vinyl ether, acrylonitrile, vinyl chloride, dichlorodifluoroethylene, or styrene. The acrylic rubbers may be mixed with 80-20 parts polychloroprene, butadiene-1,3-styrene copolymer, or natural rubber.  Example VI describes a uniform mixture of silicon monoxide, natural rubber, zinc oxide, pine tar, phenyl naphthylamine, stearic acid, didodecylamine, and sulphur.  Specifications 804,991, [Group III], and 804,993 are referred to.