GB1221889A - Paint binders - Google Patents

Abstract

1,221,889. Radiation curable polymeric compositions. FORD MOTOR CO. Ltd. 22 Aug., 1969 [4 Nov., 1968 (2)], No. 41919/69. Heading C3P. [Also in Division B2] A radiation-curable paint binder comprises a solution in one or more liquid vinyl monomers of a binder resin derived from vinyl monomers and having alpha, beta-olefinically unsaturated side chains attached thereto through two ether linkages. Substrates such as metal, wood or polymeric solids have applied to them a film 0À1-4 mils. thick of a paint consisting essentially of the paint binder and the surface is cured in a nitrogen atmosphere with 1-25 Mrads of irradiation from a beam of electrons having an energy of from 100,000 to 500,000 electron volts. The paint binder contains between 15 and 75% by weight of liquid vinyl monomer. The binder resin, which may have from 0À5 to 5 alpha, beta-olefinic unsaturated units per 1000 of molecular weight, is prepared by either of the following methods: (A) copolymerizing an allylic alcohol with one or more different vinyl monomers and then reacting the resulting copolymer with an allylic glycidyl ether; or (B) copolymerizing an allylic glycidyl ether with one or more different vinyl monomers and then reacting the resultant copolymer with an allylic alcohol. Examples illustrating method A disclose the copolymerization in xylene of allyl alcohol, ethyl acrylate and methyl methacrylate in the presence of benzoyl peroxide, and the reacting of the resulting copolymer with allyl glycidyl ether in the presence of potassium hydroxide to give the binder resin. The film-forming paint binder is prepared by addition of styrene (containing hydroquinone) to the binder resin. In further examples the styrene is replaced by the following: methyl methacrylate; ethyl acrylate, 2-ethyl hexyl acrylate and styrene ; methyl methacrylate and vinyl toluene; butyl methacrylate and styrene; ethyl acrylate, butyl acrylate and alpha-methyl styrene. In further examples the comonomers in the first stage are 1-penten-5-ol or 9-decen-1-ol or 3-phenyl-2- propen-1-ol, butyl acrylate and styrene; allyl, 1-butene or cinnamyl glycidyl ether may be employed in the second stage, and the resulting binder resin is dispersed in methyl methacrylate, or a mixture of methyl methacrylate and styrene. Examples illustrating method B disclose inter alia the copolymerization in xylene of allyl glycidyl ether, ethyl acrylate and methyl methacrylate in the presence of benzoyl peroxide, and the reacting of the resulting copolymer with allyl alcohol in the presence of potassium hydroxide. The binder resin is dispersed in styrene (containing hydroquinone). In further examples, the allyl glycidyl ether is replaced by 1 -butene or cinnamyl glycidyl ether. Minor amounts of such monomers as acrylonitrile, acrylamide, N-methylol acrylonitrile, vinyl chloride or vinyl acetate may be associated with the acrylate monomers and/or vinyl hydrocarbon monomers. The binder resin and liquid vinyl monomer should constitute at least 85 % by weight of the paint binder. Minor amounts of allylic compounds may be used to make up the balance, if any.