Mixtures of epoxy resins with cationic initiators are curable under high energy ionizing radiation such as electron beam radiation, X-ray radiation, and gamma radiation. The composition of this process consists of an epoxy resin, a cationic initiator such as a diaryliodonium or triarylsulfonium salt of specific anions, and a toughening agent such as a thermoplastic, hydroxy-containing thermoplastic oligomer, epoxy-containing thermoplastic oligomer, reactive flexibilizer, rubber, elastomer, or mixture thereof. Cured compositions have high glass transition temperatures, good mechanical properties, and good toughness. These properties are comparable to those of similar thermally cured epoxies.
This invention was made with Government support under contract DE-AC05-4OR21400 awarded by the U.S. Department of Energy to Lockheed Martin Energy Systems, Inc. and the Government has certain rights in this Invention.