Radiation shielding materials are necessary for protecting astronaut crews from the hazards of space radiation during future NASA missions. Although polyethylene based materials and composites are attractive for radiation shielding due to high hydrogen content, the poor thermal performance has limited its use as a "parasitic", nonstructural material. Further impeding use of this material is its inherent flammability. Accordingly, thermally stable structural materials having low flammability combined with radiation shielding are necessary for the development of next generation aerospace structures and vehicles. It would be further desirable that the non-parasitic material has excellent damage tolerance to mitigate impact events in operation. Applied Poleramic, Inc. proposes to develop a new generation of structural high hydrogen content matrix materials which will be combined with an interlayer modification approach to result in fiber reinforced composite materials having enhanced radiation shielding combined with excellent damage tolerance and improved flammability resistance. This will be achieved through development of high hydrogen content bismaleimide resins followed by fabricating carbon fiber composites having nuclear grade boron carbide or boron nitride micro-particles in the interlayer region.