Patent GB-934038-A (GB)
Title: Polymer dispersions in organic liquid media and methods of preparation
IPC: C08F265/04
Filed: 1959-08-31
Abstract: The surfaces of wood, metals, ceramics, concrete, bricks, stones, plaster, glass, vinyl tiles and asbestos cement products are coated by applying thereto a composition comprising a substantially anhydrous dispersion in a liquid hydrocarbon of a linear polymer of at least one of acrylic or methacrylic acids, amides, nitriles or C1-C18 esters, and a hydrophobic dispersing agent which is a graft copolymer, one component of which is preferentially soluble in the linear polymer and the other is preferentially soluble in the hydrocarbon medium.  In the examples: (1) a glass plate is coated with mineral spirits dispersion of a methyl methacrylate-ethyl acrylate-maleic anhydride copolymer stabilized by a graft copolymer of the aforesaid monomers and rubber, and the resulting coating is baked at 150 DEG C.; (5) a metal plate primed with an epoxy resin is coated with a mineral spirits dispersion of polymethyl methacrylate stabilized by a methyl methacrylate-butyl rubber graft copolymer; (6) as in (5) but using octane as the dispersing medium and a methyl methacrylatecyclized rubber dispersant; and (9) vinyl and linoleum wall tiles are coated with an octane dispersion of a methyl methacrylate-ethyl acrylate copolymer stabilized by a graft copolymer of the aforesaid monomers and poly(isobornyl methacrylate).ALSO:Compositions comprising a substantially anhydrous dispersion in a liquid hydrocarbon medium of a linear polymer are made by polymerizing in the hydrocarbon medium a monomer charge which gives rise to a polymer which is insoluble in the medium and which comprises one or more ethylenic monomers including at least one of acrylic and methacrylic acids, their amides, nitriles and esters with a C1-C18 alcohol or phenol, the hydrocarbon medium containing a hydrophobic dispersing agent which is a graft copolymer having a first component preferentially soluble in the liquid medium and grafted thereon a second component preferentially soluble in the dispersed polymer, whereby the latter is formed as discrete particles dispersed in the medium and at least 90% by weight of which have a particle size not exceeding 10 microns.  The graft copolymer dispersant may be formed in the following ways: (A) by dissolving a precursor polymer, e.g. a rubber, in the hydrocarbon medium together with a free-radical catalyst, e.g. a peroxide, activating the precursor by heating, adding the monomer charge which is to form the dispersed polymer and then polymerizing it; (B) as in (A) but without the preliminary activation of the precursor; (C) as in (A) but using only a part of the monomer charge in a preliminary polymerization, followed by the polymerization of the remainder of the monomer; (D) using cationic polymerization catalysts instead of free-radical catalysts in the above processes; and (E) as in (D) but using anionic catalysts.  Precursor polymers specified are natural rubber and modified natural rubbers, polyisobutylene, butyl rubber, chlorinated butyl rubber, homo- and copolymers of butadiene, polyisoprene, polychloroprene, homo- and copolymers of acrylic and methacrylic esters, oxidized vegetable oils and polymers of terpenes.  The acrylic monomers for making the dispersed polymer may be used alone or in admixture with comonomers such as styrene, methyl styrenes, fumaric and crotonic acids, allyl acetate, hydroxyethyl vinyl ether and sulphide, vinyl pyrrolidone, ethylene, propylene, vinyl and vinylidene fluorides, hexafluoropropylene, chlortrifluoroethylene and tetrafluoroethylene.  The resulting dispersions are used for various coating and impregnating purposes and may be modified by the addition of drying oils, pigments, fatty acid modified shellac, epoxidized fatty oils, epoxy resins and the alkylated methylolated condensation products of formaldehyde with urea, thiourea, melamine, benzoguanamine and ethyleneurea, and plastisols made from vinyl chloride polymers.  The examples describe the following procedures: (1) activating a solution of crepe rubber in mineral spirits with lauroyl peroxide and polymerizing a mixture of methyl methacrylate, ethyl methacrylate and maleic anhydride therein; (2) polymerizing a mixture of acrylonitrile, butyl acrylate and maleic anhydride in an octane-dimethyl formamide solution of a vinyl toluene-butadiene copolymer with the aid of a mixture of benzoyl and lauroyl peroxides and dimethyl-p-toluidine; (3) as in (2) but using acrylonitrile-butyl acrylate and acrylonitrile-2-ethylhexyl acrylate monomer mixtures; (4) polymerizing methyl acrylate in an octane solution of a vinyl toluene-butadiene copolymer with the aid of lauroyl peroxide; (5) polymerizing methyl methacrylate in a mineral spirits solution of butyl rubber with the aid of benzoyl peroxide; (6) polymerizing methyl methacrylate in an octane solution of cyclized rubber with the aid of benzoyl peroxide; (7) activating a solution of a vinyl pyrollidone-butylacrylate-lauryl methacrylate-stearyl methacrylate copolymer in toluene with benzoyl peroxide and polymerizing a mixture of methyl methacrylate and ethyl acrylate therein; (8) activating a solution of a butadiene-styrene copolymer in toluene with benzoyl peroxide and polymerizing a mixture of ethyl acrylate and methacrylic acid therein; (9) activating a solution of poly(isobornyl methacrylate) in octane with benzoyl peroxide and polymerizing a mixture of methyl methacrylate and ethyl acrylate therein; (10) polymerizing a mixture of methyl methacrylate and ethyl acrylate in an octane solution of oxidized linseed oil; (11) polymerizing methyl methacrylate in a heptane solution of poly(lauryl methacrylate); (12) activating a solution of natural rubber in an octane-toluene mixture with benzoyl peroxide and polymerizing a mixture of methyl methacrylate and ethyl methacrylate therein; (13) polymerizing methyl methacrylate in a hexane solution of butyl rubber with the aid of azobisisobutyronitrile and UV-light; (14) polymerizing methacrylic acid in a mineral spirits solution of a vinyl toluene-butadiene copolymer with the aid of lauroyl peroxide; (15) activating a solution of a styrene-butadiene copolymer in toluene with benzoyl peroxide and polymerizing a mixture of ethyl acrylate and methacrylic acid therein; (16) polymerizing methyl methacrylate in a solution of chlorobutyl rubber in hexane (pre-dried) with aid of butyl lithium as a catalyst; and (17) dissolving a graft copolymer of crepe rubber and poly(methyl methacrylate) in n-hexane and polymerizing a mixture of methyl acrylate and methacrylate therein with the aid of butyl lithium as a catalyst.ALSO:Textile materials are treated with a composi-tion comprising a substantially anhydrous dispersion in a liquid hydrocarbon medium of a linear polymer of at least one of acrylic or methacrylic acids, amides, nitriles or C1-C18 esters, and a hydrophobic dispersing agent which is a graft copolymer, one component of which is preferentially soluble in the linear polymer and the other is preferentially soluble in the hydrocarbon medium. In the examples: (8) cellulosic yarns are warp sized by passage through a toluene dispersion of an ethyl acrylate-methacrylic acid copolymer stabilized by a graft copolymer of the aforesaid monomers and a butadiene-styrene copolymer, the resulting size is removable by aqueous sodium carbonate; and (14) nylon yarns are sized by applying thereto a mineral spirits dispersion of poly-methacrylic acid stabilized by a graft copolymer of methacrylic acid and a vinyl toluene graft copolymer.