PROCESS FOR CONTROLLING GELATION AND CURE OF UNSATURATED RESINS

摘要

A process for controlling the gelation and cure rate of unsaturated resins useful for thermosettable compositions and laminates. A small amount of an enolizable beta-diketone such as 2,4-pentadione added to a vinyl ester of a polyglycidyl ether of a polyhydric compound, an unsaturated polyester or a mixture thereof contributes toward the control of the rates. Admixed with the enolizable beta-diketone and unsaturated resin is a peroxide selected from ketone peroxides, tertiary hydroperoxides or peroxyesters, and a redox reactive metal salt soluble in the curable resin such as cobalt naphthenate. The unsaturated resins have a pH greater than 5.7 measured as a 10 percent methanol solution. The mixture is maintained at a temperature less than 54oC to extend the nongelled state and then raised above 54oC to achieve acceleration of the cure rate.