Interpenetrating polymer network approach to tough and microcracking resistant high temperature polymers. Part III. LaRC‐RP71

A high performance semi‐interpenetrating polymer network (semi‐IPN) has been synthesized from Thermid‐600 and LARC‐TPI. Notable improvements in resin fracture toughness and graphite fiber reinforced composite microcracking resistance over the unmodified Thermid‐600 neat resin and composite have been realized. The chemistry, processing, physical and mechanical properties, and phase morphology of the neat resin and composite reinforced with graphite fibers are presented.