Conductive Polymer/Carbon Nanotube Structural Materials and Methods for Making Same

Carbon nanotubes (CNTs) show promise for multifunctional materials for a range of applications due to their outstanding combination of mechanical, electrical and thermal properties. However, these promising mechanical properties have not translated well to CNT nanocomposites fabricated by conventional methods due to the weak load transfer between tubes or tube bundles. In this invention, the carbon nanotube forms such as sheets and yarns were modified by in-situ polymerization with polyaniline, a -conjugated conductive polymer. The resulting CNT nanocomposites were subsequently post-processed to improve mechanical properties by hot pressing and carbonization. A significant improvement of mechanical properties of the polyaniline/carbon nanotube nanocomposites was achieved through a combination of stretching, polymerization, hot pressing, and carbonization. Scientists at NASA Langley Research Center have developed a composite material that demonstrates improved mechanical properties, approaching those of conventional carbon fiber composites, and possesses relatively high electrical conductivity. Starting with carbon nanotube paper, tape or yarn, the CNT material was impregnated with monomeric aniline with was then polymerized in-situ to create a nanocomposite, followed by stretching, hot pressing and carbonization to densify and improve the interface integrity.