Epoxy resin advanced with diphenol/diglycidyl ether adducts

A curable composition comprising a curing quantity of a suitable curing agent and a composition comprising a mixture of

• (A) an advanced epoxy resin resulting from reacting a composition comprising
• (1) the aromatic hydroxyl-containing product resulting from reacting a composition comprising
• (a) at least one diglycidyl ether of (i) an oxyalkylated aromatic diol, or (ii) at least one compound having two hydroxyl groups per molecule in which the hydroxyl groups are attached to an aliphatic or cycloaliphatic carbon atom and which compound is free of aromatic rings;
• or (iii) a combination of (i) and (ii);
• and (iv) optionally, a diglycidyl ether compound different from (i) and (ii) which is present in an amount such that the amount of epoxy groups contributed by component (iv) based upon the total amount of epoxy groups contributed by components (i), (ii) and (iv) is from about zero to about 75 percent;
• and
• (b) at least one compound containing two aromatic hydroxyl groups per molecule;
• wherein components (a) and (b) are employed in amounts such that there are more aromatic hydroxyl groups present than glycidyl ether groups;
• (2) at least one diglycidyl ether of a compound containing two aromatic hydroxyl groups per molecule;
• (3) optionally, one or more compounds containing two aromatic hydroxyl groups per molecule;
• and
• (4) optionally, a monofunctional capping agent;
• and
• (B) at least one diglycidyl ether of a compound having two aromatic hydroxyl groups per molecule;
• wherein components (A1) and (A2) are employed in amounts such that the resultant product has an epoxide equivalent weight greater than that of component (A2);
• component (A3), when present, is employed in an amount which provides a total amount of aromatic hydroxyl groups from components (A1) and (A3) per epoxide group contained in component (A2) of from about 0.5:1 to about 0.95:1;
• and component (A4) is present in an amount which provides a ratio of epoxy-reactive groups contained in component (A4) per glycidyl group not consumed by reaction of components (A1) and (A3) with component (A2) of from about zero:
• 1 to about 0.7:1;
• and components (A) and (B) are present in an amount such that from about 25 to about 95 percent of the total amount of glycidyl ether groups are contributed by component (A) and from about 75 to about 5 percent of the total amount of glycidyl ether groups are contributed by component (B).