LOW VISCOSITY EPOXY RESINS AND LOW VOC CURABLE FORMULATIONS THEREFROM
The present invention provides methods of making a low viscosity C 15 alkenyl group containing diglycidyl ether composition comprising at least partially distilling a mixture of one or more C 15 alkenyl group containing monoglycidyl ether and one or more C 15 alkenyl group containing diglycidyl ether in the presence of a free radical inhibitor to remove at least some of the C 15 alkenyl group containing monoglycidyl ether. The methods enable high solids, low viscosity epoxy resins from a renewable source. The present invention also provides compositions of C 15 alkenyl group containing diglycidyl ether adducts of a polyamine.
1 . A method of forming a low viscosity epoxy resin composition comprising distilling an epoxy resin mixture of one or more C 15 alkenyl group containing monoglycidyl ether and one or more C 15 alkenyl group containing diglycidyl ether in the presence of a free radical inhibitor to at least partially fractionate the diglycidyl ether from the monoglycidyl ether.
2 . The method as claimed in claim 1 , wherein the free radical inhibitor is chosen from a phenol having one bulky group ortho to the OH group, a phenol having two bulky groups ortho to the OH group, and an aryl benzofuranone.
3 . The method as claimed in claim 1 , wherein the mixture of one or more C 15 alkenyl group containing monoglycidyl ether and one or more C 15 alkenyl group containing diglycidyl ether has up to 30 wt. %, based on the total solids of the epoxy resin mixture, of a C 15 alkenyl group containing monoglycidyl ether.
4 . The method as claimed in claim 1 , further comprising forming the mixture of one or more C 15 alkenyl group containing monoglycidyl ether and one or more C 15 alkenyl group containing diglycidyl ether by epoxidizing a mixture of one or more cardol and one or more cardanol with an epihalohydrin prior to the distilling.
5 . The method as claimed in claim 1 , wherein the resulting epoxy resin composition comprises 15 wt. % or less of oligomers resulting from side chain coupling reactions of alkenyl groups, based on the total solids of the given epoxy resin composition.
6 . The method as claimed in claim 1 , wherein the resulting epoxy resin composition comprises 10 wt. % or less of oligomers resulting from side chain coupling reactions of alkenyl groups, based on the total solids of the given epoxy resin composition.
7 . The method as claimed in claim 1 , further comprising reacting the one or more C 15 alkenyl group containing diglycidyl ether with a polyamine to form a polyamine adduct of the C 15 alkenyl group containing diglycidyl ether.
8 . The method as claimed in claim 7 , wherein the polyamine is diethylenetriamine.
9 . A low viscosity and low VOC epoxy resin composition comprising an adduct of a polyamine and one or more C 15 alkenyl group containing diglycidyl ether.
10 . A rapid cure liquid coating composition comprising an adduct of a polyamine and one or more C 15 alkenyl group containing diglycidyl ether and having a solids content of 85 wt. % solids or higher, based on the total weight of the composition.