Scientists employ carbon nanofibers to increase the conductivity of polymeric materials.

AFRL scientists have developed a method for uniformly dispersing carbon nanofibers throughout polymeric materials to increase their conductivity. Engineers will be able to employ the resulting polymeric nanocomposites in conductive paints, coatings, caulks, sealants, adhesives, fibers, thin films, thick sheets, tubes, and large structural components needed for both aerospace and industry applications.

In performing nanoscience research, materials scientists seek to observe and ultimately manipulate materials and their properties on the nanoscale. Nanoscience and technology affords unique opportunities to create revolutionary material combinations. Such combinations enable new properties and exploit the synergism existing between constituent materials only when the materials’ morphology and fundamental physics coincide at the nanoscale. Adding carbon nanofibers into a polymeric material enhances the material’s dimensional stability, abrasion resistance, electrical and thermal conductivity, and tribological properties (e.g., reduced surface friction).

Scientists from AFRL and the University of Dayton Research Institute (UDRI) initiated an in-house research program with the goal of developing conductive nanocomposites using low-cost, multiwalled nanotubes. This concept held significant promise for a variety of commercial and military applications but was largely unexplored prior to this program. The collaborative effort ultimately yielded a proven process for uniform dispersement of vapor-grown carbon nanofibers throughout a wide variety of polymer matrices (see figure on previous page). The method combines nanofibers with a solvent to form a solution and then introduces a polymer to the original solution to form another, nearly homogeneous mixture. Evaporation or coagulation subsequently removes the solvent from the mixture.