Patent GB-941305-A (GB)
Title: Polymer dispersions
Inventor: OSMOND DESMOND WILFRID JOHN
IPC: C08F2/06
Filed: 1958-11-05
Abstract: 941,305. Polymer dispersions. IMPERIAL CHEMICAL INDUSTRIES Ltd. Oct. 26, 1959 [Nov. 5, 1958; May 1, 1959], Nos. 35503/58 and 15051/59. Heading C3P. Dispersions of synthetic polymers in organic liquids are made in which the dispersed particles are stabilized by a block or graft copolymer of which one constituent of molecular weight of at least 1000 is solvated by the organic liquid and another constituent forms an integral part of the polymer particles. The dispersions may be made by the following processes: (A) by precipitating the polymer in the organic liquid in the presence of a preformed block or graft polymer of which one constituent is solvated by the organic liquid and another co-precipitates with the polymer; (B) by polymerizing monomer in an organic liquid in which the resulting polymer is insoluble in the presence of a preformed block or graft copolymer of the type specified in (A); (C) by polymerizing monomer in an organic liquid in which the resulting polymer is insoluble in the presence of a polymer on which the monomer grafts to form a graft polymer of the above type; and (D) by polymerizing in organic solution a monomer and preformed polymer containing an ethylenic group which can copolymerize with the monomer to form a solution of polymeric material which is then dispersed in an organic liquid which is a non-solvent for the polymeric product of the monomer, but which solvates the preformed polymer. The examples describe the preparation of polymer dispersions by the following methods: (1-3) polymerizing methyl methacrylate in a white spirit solution of degraded crepe rubber in the presence of benzoyl peroxide; (4) as above but using a monomer mixture of ethoxyethyl methacrylate, ethyl acrylate and maleic acid; (5) as in (4), but replacing the ethoxyethyl methacrylate by acrylonitrile; (6) as above, but using a mixture of high and medium boiling paraffins in place of the white spirit; (7) as in (3) but using polybutadiene in place of the rubber; (8) as in (1) but using gutta percha in place of the rubber; (9) as in (1), but using linseed stand oil in place of the rubber; (10) as in (1), but using in place of the rubber a benzene solution of a graft copolymer of a mixture of methyl and butyl methacrylates and a degraded rubber; as in (10), but using azodiisobutyronitrile as the initiator; (12) as in (1), but using in place of the rubber a benzene solution of a graft copolymer of methyl methacrylate and degraded rubber; (13) as in (12) with the addition of lauryl mercaptan during the reaction; (14) as in (1), but using a mixture of petroleum ether and white spirit as the organic liquid; (15) polymerizing styrene in ethyl alcohol in the presence of methyl ethyl ketone peroxide and a block copolymer obtained by masticating methracrylic acid and polystyrene; (16) as in (15) but using ethyl alcohol containing a small proportion of water: (17) as in (15), but using a graft copolymer of methacrylic acid and polybutadiene in place of the block copolymer; (18) polymerizing vinyl toluene in acetone in the presence of methyl ethyl ketone and a block copolymer of vinyl toluene and methyl methacrylate prepared by anionic catalysis; (19) polymerizing lauryl methacrylate in ethyl alcohol in the presence of methyl ethyl ketone peroxide and a block copolymer obtained by masticating lauryl methacrylate with methacrylic acid; (20) adding white spirit to a mixture of a methyl isobutyl solution of a vinyl chloride/vinyl acetate copolymer and a benzene solution of a graft copolymer of methyl and butyl methacrylates and polybutadiene; (21) adding butyl acetate to a benzene solution of polyethylene and a methyl methacrylate/polyethylene graft copolymer prepared by an irradiation process; (22) polymerizing methyl methacrylate in white spirit in containing a mixed behenic acid/methacrylic acid ester of a styrene-allyl alcohol copolymer; (23) as in (22) but using xylene in place of white spirit, and adding mineral spirits to the polymerized mixture; (24) polymerizing methyl methacrylate in the presence of a benzene solution of the methacrylic ester of a butyl methacrylate - allyl alcohol copolymer; and (25) a mixture of white spirit and petroleum ether is added to a solution in benzene of a methyl methacrylate-methacrylic acid copolymer esterified with the product obtained by esterifying a styrene-allyl alcohol copolymer with stearic acid. A coating composition is described comprising the dispersion of (14) to which is added methylcyclohexanyl phthalate, titanium dioxide, a long oil alkyd resin dispersing aid and aliphatic hydrocarbon thinner.