SBIR-STTR Award

A new nanoscale polymer composite additive having shear thickening properties is proposed for improving the ballistic properties of polycarbonate-based transparent armor. The proposed research explores the feasibility of modifying conventional polycarbonate thermoplastics with nano-dispersed inorganic ceramics and novel copolymer additives to enhance the ballistic resistance of these transparent armor materials. The nano-scale ceramic phases dispersed within copolymer micromatrices will improve the ballistic impact resistance of the plastic armor through a non-Newtonian flow behavior. The proposed additives will be designed to preserve the hardness and transparency of the polycarbonate while improving the overall ballistic survivability. The ultimate objective is to develop an easily processed nanoscale ceramic reinforced polycarbonate hybrid with high toughness, the transparency of virgin polycarbonate and enhanced ballistic resistance. In the proposed study, the methodology for preparing these novel shear-thickening hybrids will be developed and structure-property profiles determined. The ballistic properties of selected hybrid materials and polycarbonate controls will be determined. The resulting material property relationships will be used in the design and fabrication of new toughened transparent armors with high survivability.

Benefits:
The benefits of an easy-to-process, impact resistant thermoplastic hybrid material include excellent environmental durability, improved ballistic resistance, and low material costs. Potential commercial applications lie in the manufacture of aerospace structures, automotive applications, building windows, protective eyewear, sporting goods, and personal armor components for both military and civilian markets.

Keywords:
transparent armor, polycarbonate, ceramic, hyrid, shear thickening

Transparent armor is a system of materials designed to be optically transparent, yet protect from ballistic impacts. A new nano-scale polymer composite additive having loading rate-dependent properties was developed for improving the ballistic properties of polycarbonate-based transparent armor. The Phase I study demonstrated the feasibility of modifying conventional polycarbonate thermoplastic with nano-scale reinforced copolymer additives that enhance the ballistic impact properties and provide adhesion to ceramics. The additives are designed to preserve the ductility and transparency of the polycarbonate while improving the overall ballistic survivability. The proposed Phase II program would extend the benefits of these versatile additives to advanced lightweight thermoplastic and laminate armors. In the proposed Phase II study, the methodology for preparing both stand-alone lightweight components and ceramic-thermoplastic laminate armor will be developed. These novel loading rate-sensitive thermoplastic nanocomposites will be optimized in terms of ballistic properties and optical transparency. The resulting material property relationships will be used to fabricate new toughened transparent armors with high survivability. Damage tolerance, mechanical properties and environmental durability of the resulting transparent armor specimens will be tested for ultimate system qualification. Cost and manufacturability studies and the fabrication of an aircraft windscreen test article will be performed.

Keywords:
Transparent Armor, Polycarbonate, Ceramic, Hybrid,