Modification of liquid hydrocarbons
AssigneeImperial Chemical Industries PLC
InventorsJohn S. Roberts, Frederick A. Waite
Life of this patent
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Abstract
Improved rate of dissolution in liquid hydrocarbon fuels, of specified tert-butylstyrene copolymers capable of imparting anti-misting characteristics to the fuel, is obtained when the copolymer, following its production by aqueous emulsion polymerization of the monomers, is isolated from the resulting latex by a process of flocculation, separation, washing and drying at moderate temperatures. The copolymer thus isolated is advantageously incorporated in the liquid fuel in the form of a slurry with a hydroxylic liquid and an amine.
Claims28
A method for the isolation in solid form, from a latex in which it has been prepared by aqueous emulsion polymerisation of the constituent monomers, of a copolymer of (i) from 75% to 98% by weight of tert-butylstyrene, (ii) from 1% to 24% by weight of a second monomer selected from the acrylic and methacrylic esters of monohydric alcohols containing from 1 to 4 carbon atoms, 2-ethoxyethyl methacrylate, acrylonitrile, vinyl acetate, styrene and vinyl toluene, and (iii) from 1% to 10% by weight of methacrylic acid, where the aggregate weight of monomers (i), (ii) and (iii) is 100%, the method consisting in the flocculation of the particles of copolymer in the latex by the addition to the latex of a flocculating agent capable of destabilising the particles therein selected from the group consisting of an aqueous solution of a quaternary ammonium salt containing in the molecule at least one organic residue attached to the nitrogen atom which contains at least 6 carbon atoms and a water-miscible organic liquid which is a non-solvent for the copolymer, and separating the flocculated copolymer from the other constituents of the latex.
A copolymer prepared by aqueous emulsion polymerisation of a mixture of (i) from 75% to 98% by weight of tert-butylstyrene, (ii) from 1% to 24% by weight of a second monomer selected from the acrylic and methacrylic acid esters of monohydric alcohols containing from 1 to 4 carbon atoms, 2-ethoxyethyl methacrylate, acrylonitrile, vinyl acetate, styrene and vinyl toluene, and (iii) from 1% to 10% by weight of methacrylic acid, the aggregate weight of monomers (i), (ii) and (iii) being 100%, the said copolymer having been isolated from the resulting latex by flocculation of the particles of copolymer therein by the addition to the latex of a flocculating agent capable of destabilizing the particles therein selected from the group consisting of an aqueous solution of a quaternary ammonium salt containing in the molecule at least one organic residue attached to the nitrogen atom which contains at least 6 carbon atoms and a water-miscible organic liquid which is a non-solvent for the copolymer, and subsequent separation of the flocculated copolymer from the other constituents of the latex.
A copolymer prepared by aqueous emulsion polymerisation of a mixture of (i) from 75% to 98% by weight of tert-butylstyrene, (ii) from 1% to 24% by weight of a second monomer selected from the acrylic and methacrylic acid esters of monohydric alcohols containing from 1 to 4 carbon atoms, 2-ethoxyethyl methacrylate, acrylonitrile, vinyl acetate, styrene and vinyltoluene, and (iii) from 1% to 10% by weight of methacrylic acid, the aggregate weight of monomers being 100%, the said copolymer having been isolated from the resulting latex by flocculation of the particles of copolymer therein by the addition to the latex of an aqueous solution of cetyltrimethylammonium bromide, followed by separation of the flocculated copolymer from the other constituents of the latex, washing of the separated copolymer with water and drying of a washed copolymer for 24 hours at 40.degree. C.
A copolymer prepared by aqueous emulsion polymerisation of a mixture of (i) from 75% to 98% by weight of tert-butylstyrene, (ii) from 1% to 24% by weight of a second monomer selected from the acrylic and methacrylic acid esters of monohydric alcohols containing from 1 to 4 carbon atoms, 2-ethoxyethyl methacrylate, acrylonitrile, vinyl acetate, styrene and vinyl toluene, and (iii) from 1% to 10% by weight of methacrylic acid, the aggregate weight of monomers being 100%, the said copolymer having been isolated from the resulting latex by flocculation of the particles of copolymer therein by the addition to the latex of methanol, followed by separation of the flocculated copolymer from the other constituents of the latex, washing of the separated copolymer with water and drying of the washed copolymer for 24 hours at 40.degree. C.
Dependencies are inferred from the claim text.