| 摘要 |
The invention comprises a heat-hardenable, non-gelled interpolymer soluble in organic solvents and which comprises a resinous hydroxy-terminated unsaturated polyurethane copolymerized with at least one ethylenically unsaturated component, at least some of the units of the interpolymer derived from the ethylenically unsaturated component containing functional groups reactive with the OH groups of the copolymerized polyurethane. The unsaturated polyurethane may be the reaction product of organic diisocyanate and hydroxy components comprising at least one ethylenically unsaturated compound containing at least one hydroxyl group, at least one alkylene glycol or polyalkylene ether glycol, and at least one saturated aliphatic polyhydroxy compound containing at least three hydroxyl groups. The interpolymer may be prepared by first reacting the ethylenically unsaturated hydroxy compound and the alkylene glycol a polyalkylene ether glycol with a stoichiometric excess of organic polyisocyanate to form an -NCO terminated intermediate, reacting the intermediate with the aliphatic polyhydric alcohol containing at least 3 -OH groups to form a resinous hydroxy terminated unsaturated polyurethane; and copolymerizing the polyurethane with the ethylenically - unsaturated component. The ethylenically-unsaturated component may contain amido groups which may be alkylolated to furnish alkylol groups reactive with the -OH groups of the polyurethane, thus providing a heat hardening cure. The ethylenically unsaturated component may be acrylamide, styrene, methyl methacrylate, ethyl acrylate and/or 2-ethylhexyl acrylate. The ethylenically unsaturated compound containing at least one -OH group used to prepare the polyurethane may be trimethylol propane diallyl ether, glycerol monoallyl ether, 2-hydroxy methyl 5-norbornene allyl alcohol, crotyl alcohol and glycerol monoacrylate. The interpolymer may be produced in a solvent, a mixture of n-butyl alcohol and 2-butoxy ethanol, and using as catalysts, azobisbutyronitrile, di-tert.-butyl peroxide, triethyl amine, benzoyl peroxide, tert.-dodecyl mercaptan, and/or cumene hydroperoxide. The amide containing interpolymer may be treated with paraformaldehyde and then etherified with n-butyl alcohol.ALSO:An enamel comprising (1) a pigment, e.g. TiO2 and (2) a heat hardenable interpolymer comprising a hydroxy terminated unsaturated polyurethane copolymerized with at least one ethylenically unsaturated component, at least some of the units of the interpolymer derived from the ethylenically unsaturated component containing functional groups reactive with the -OH groups of the copolymerized polyurethane, and (3) a solvent is applied to an phosphate treated aluminium coil and baked. The coatings may also contain aminoplasts, alkyld resins, epoxy resins and vinyl resins. |
