TOUGH HIGH MODULUS EPOXY CASTING MATERIALS

THE OVERALL OBJECTIVE OF THIS PROJECT IS TO DEMONSTRATE THE FEASIBILITY OF PREPARING LOW VISCOSITY, ROOM TEMPERATURE CURABLE, TOUGH, HIGH MODULUS EPOXY CASTING MATERIALS USING POLY(ARYL ETHER KETONES) AND POLY(ARYL ETHER SULFONE KETONE) COPOLYMERS AS IMPACT MODIFIERS. TOUGH, HIGH MODULUS CASTING MATERIALS ARE NOT AVAILABLE. AS THE MODULUS INCREASES, THE BRITTLENESS OF THE CONVENTIONAL PLASTICS ALSO INCREASES. BLENDING CERTAIN THERMOPLASTICS WITH EPOXY RESINS PRIOR TO NETWORK FORMATION IMPROVES THE FRACTURE TOUGHNESS WITH A RETENTION OF THE HIGH MODULUS. THE IMPROVEMENT IN TOUGHNESS RESULTS FROM DUCTILE YIELDING OF THE THERMOPLASTIC MODIFIER PARTICLES WHICH SEPARATE OUT DURING CURING. DURING PHASE I, THE EFFECT OF MOLECULAR WEIGHT AND CONCENTRATION OF THERMOPLASTIC MODIFIER ON THE VISCOSITY OF THE CASTING AND ON THE MECHANICAL PROPERTIES OF THE CURED EPOXY NETWORKS WILL BE DETERMINED. PHASE II WILL EMPHASIZE MORE DETAILED CHARACTERIZATION OF THE CASTING MATERIAL IN THE UNCURED STATE AND MORE COMPREHENSIVE TESTS OF THE CURED EPOXY NETWORKS. ACCELERATED AGING TESTS INCLUDING THERMAL AND HUMIDITY CYCLING WILL BE DEFERRED UNTIL PHASE II.