High Strength-to-Weight Ratio Structural Hybrid Polymers for GMD Missile Systems

"BMDO needs advanced materials to withstand harsh loading, acoustic, and thermal environments, while minimizing weight for ground-based antiballistic missile interceptors. Physitron is developing an organic/inorganic hybrid material that will increase theeffectiveness of Ground-based Midcourse Defense (GMD). The innovation is embodied in nanoparticles called graphitic carbon nanofibers (GCNFs). GCNFs, which differ fron carbon nanotubes, have a specifically altered surface chemistry that covalently binds tothe backbone of a polymer matrix. When the GCNFs are integrated into the polymer a hybrid material is created that possesses enhanced material properties. There is little increase with respect to the material's specific gravity due to the highstrength-to-weight ratio of GCNFs and their covalent binding in the matrix. This hybrid material system can be applied to a wide variety of polymers. Also, the particle geometry, size, and surface chemistry can be varied to suit the applicationrequirements. Strength enhancements in polymer components are 120% or greater with respect to ultimate strength. Phase I will be a feasibility study that consists of polymer matrix selection, GCNF synthesis, GCNF integration into the polymer matrix, andmaterials tests. Phase II will refine synthesis and integration technologies, investigate other polymers, and scale up hybrid materials production. The development of hybrid materials technologies under this