Method of water-solubilizing high performance polyether epoxide resins, the solubilized resins and thermoset, hydrophobic coatings derived therefrom

A process for making water-thinnable, base-neutralized, acidic resins which are convertible to hydrophobic, high performance, thermoset resins, said process comprising:

• (I) reacting orthophosphoric acid with a polyether epoxide resin E.sup.1 consisting essentially of molecules of the formula ##STR47## wherein Q, independently, in each occurrence, is ##STR48## n is an integer of from 0 to 40, r is zero, 1 or 2 and, independently in each occurrence;
• R.sup.1 is H, methyl or ethyl,
• R.sup.2 is --Br, --Cl or a C.sub.1 to C.sub.4 alkyl or alkenyl group,
• R.sup.3 is a C.sub.1 -C.sub.4 alkylene or alkenylene group,
• >C(CF.sub.3).sub.2, --CO--, --SO.sub.2 --, --S--, --O-- or a valence bond,
• R.sup.4 is --Br, --Cl or a C.sub.1 to C.sub.4 alkyl or alkenyl group;
• and
• R.sup.5 is H or alkyl of 1 to 12 carbons,
• said reaction being carried out by contacting E.sup.1 with an orthophosphoric acid source material and from 0 to about 25 molecular proportions of water per molecular proportion of H.sub.3 PO.sub.4 provided by said source material, until the fraction of the oxirane groups in E.sup.1 converted is such that when the resulting product is at least partially salified with a base, an aqueous dispersion which contains essentially no co-solvents or dispersing agents can be formed from it,
• the amount of orthophosphoric acid included as such in said source material, or obtainable therefrom by hydrolysis, being such as to provide from about 0.3 to about 2.8 P-OH hydroxyl groups per oxirane group, and
• (II) salifying the resultant reaction product with at least sufficient of a base to render it water-thinnable.