Transparent Glass Fiber Reinforced Armor

Transparent armor face shields for soldiers are problematic because desirable mechanical properties must be coupled with good transparency and low areal densities. Despite excellent properties offered by polycar-bonates their properties have not kept up with advances in non-transparent armor. New materials are needed. Mayaterials believes that transparent glass fiber reinforced composites, FRCs could be made if the matrix refractive index matches that of the fibers. Work in Japan has demonstrated the feasibility of this approach. The key is to match the RI of the fiber (1.45-1.56 for E, D, S glass) with that of the matrix, while providing good mechanical properties. Mayaterials is commercializing cubic silsesquioxane Q8 and T8 products that offer considerable potential as matrix materials with high strengths, good transparency, and good abrasion resistance. Because they are spherical nanoparticles they can be assembled with excellent control of periodicity in 1, 2 or 3-D allow excellent tailoring of mechanical and photonic properties. Ma-yaterials, in collaboration with the University of Michigan will develop silsesquioxane systems using 3 approaches including self-curing silsesquioxanes, sol-gel processed materials and possibly epoxy resins to develop matrix materials with optimal RI and mechanical properties. Phase I efforts test sets of matrix and fiber systems and downselect several for further refinement in Phase II.