Hydrolyzed ethylene vinyl acetate encapsulating coating

Claim 1

A process for forming a highly impermeable, substantially non-porous, adherent encapsulated, coated metallic substrate which comprises applying to the entire surface of the substrate to be coated a solution comprising hydrolyzed ethylene vinyl acetate polymer having a degree of hydrolysis of about 10 to 75%, a vinyl acetate content of about 3 to 45 mole %, a molecular weight of about 30,000 to 200,000 and a melt index of about 2 to 80, a solvent, and a polyisocyanate cross-linking agent; removing the solvent and cross-linking said polymer wherein said hydrolyzed ethylene vinyl acetate polymer is prepared by reacting ethylene-vinyl acetate polymer in a hydrocarbon solvent medium with a low-boiling alcohol in an alcoholysis reaction in the presence of an acid or alkaline catalyst while regulating the water present during the course of the reaction such that it does not vary by more than 50 wt.% from the initial water content, and terminating the reaction upon hydrolyzing the polymer to the degree desired, wherein the low-boiling alcohol is reacted in an amount of about 4 to 9 times the amount stoichiometrically required for the degree of hydrolysis desired.