Functionalized Single Walled Carbon Nanotubes for High Performance Composites

New material systems are required as a result of advanced performance criteria for the next generation destroyer program and other Navy ships. As a part of these requirements there is high demand for high strength structural composites. The objective of the STTR Phase II project is to develop high strength and light weight structural composites utilizing functionalized single-walled carbon nanotubes (SWNTs) as a nanoscale reinforcement. We propose to significantly increase the out-of-plane mechanical properties of the carbon fiber/epoxy composites by the introduction of SWNTs; SWNTs are considered to be the ideal reinforcing agent for advanced polymer composites because of their tremendous mechanical strength, exceptional electronic and thermal properties, nanometer scale diameter, high aspect ratio and light weight. Our approach is to apply chemistry to modify the SWNTs and engineer the interfacial interaction with the resins, because the formation of a strong interface is a critical step in the efficient translation of the excellent mechanical properties of SWNTs into the composite materials. In Phase I of this STTR project we demonstrated the feasibility of utilizing chemically modified SWNTs for the VARTM fabrication of carbon fiber/epoxy composites and showed that the incorporation of SWNTs improved shear strength and preserved in-plane mechanical properties.