Patent GB-1101984-A (GB)
Title: Polymer dispersions
IPC: C08F2/04
Filed: 1966-01-27
Abstract: A process for preparing a dispersion of a synthetic organic addition polymer in an organic liquid comprises polymerizing a monomer in the organic liquid in the presence of a graft copolymer having a component soluble in the liquid and a component which is insoluble in the liquid, incompatible with the synthetic addition polymer but is soluble in or at least swollen by the monomer of the said addition polymer. Suitable addition polymers, organic liquids and graft copolymers are listed, as are coalescing agents and phthalate plasticizers which may be added, together with pigments, to the dispersions to yield coating compositions.  In examples (1) poly-2-ethylhexyl acrylate is graft polymerized with vinyl acetate using t-bu perpivalate (a) as catalyst and methyl methacrylate is polymerized in a liquid hydrocarbon medium containing the graft copolymer and azobisbutyronitrile (b) as catalyst; (2) an a -methyl styrene/1,3-butadiene copolymer is graft polymerized with methyl methacrylate in a liquid hydrocarbon medium using benzoyl peroxide (c) as catalyst and acrylonitrile is polymerized in the resulting dispersion in the presence of dodecyl mercaptan and additional catalyst; (3) poly (2-ethylhexyl acrylate) is graft polymerized with methyl methacrylate using catalyst (a) and styrene is polymerized in a hydrocarbon medium containing the graft copolymer and catalyst (b); (4) an a -methyl styrene/1,3-butadiene copolymer is graft polymerized with methyl vinyl ketone and methyl methacrylate is polymerized in a medium containing the graft copolymer, by the procedure of Example 2; (6) polymethyl methacrylate is graft polymerized with lauryl methacrylate and a polymethyl methacrylate dispersion is produced as in Example 4; (7) an ethylene glycol condensate is graft polymerized with methyl methacrylate using catalyst (a) and methyl methacrylate is polymerized in a methanol medium containing said graft polymer, and catalyst (b).  The dispersions produced may be mixed with TiO2, butyl benzyl phthalate, mineral spirits and 2-ethoxyethyl acetate and the resulting composition is used to coat automobiles (see Division B2).ALSO:A coating composition comprises a dispersion of a synthetic organic addition polymer in an organic liquid, prepared by polymerising a monomer in the liquid in the presence of a graft polymer (see Division C3).  The composition may be applied to metal, wood, plastic, paper, glass and fabric substrates.  In examples, TiO2, butyl benzyl phthalate, mineral spirits and 2-ethoxyethyl acetate are added to dispersions of (1) polymethyl methacrylate and a graft polymer of vinyl acetate on poly (2-alkylhexyl acrylate), (2) polyacrylonitrile and a graft polymer of methyl methacrylate on an a -methyl styrene/1,3-butadiene copolymer, (3) polystyrene and a graft polymer of methyl methacrylate on poly (2-ethylhexyl acrylate), (4) polymethyl methacrylate and a graft polymer of methyl vinyl ketone on an a -methyl styrene/1,3-butadiene copolymer, (6) polymethyl methacrylate and a graft polymer of lauryl methacrylate on polymethyl methacrylate and (7) polymethyl methacrylate and a graft polymer of methyl methacrylate on an ethylene glycol condensate.  The resulting compositions are sprayed on to a primed automobile.