Addition of carbon nanotubes: an efficient way to make conventional polymers conductive
Due to their exceptional properties, carbon nanotubes become subject of quite a number of research projects in materials science. Only very small amounts of these tubes of inner diameters of 3 to 5 nm and lengths of 1 to 10 micrometers are necessary to form a percolation network in a polymer matrix and, consequently, to obtain electrostatic or conductive properties of the intrinsically isolating polymer materials. In addition, they may serve to improve material properties like mechanical strength and fire resistance.
Cryofracture of composites of polycarbonate and 1.5 weight% of multiwalled carbon nanotubes (MWNT). (The MWNT have been synthesized at the Leibniz-Institute of Solid State and Materials Research Dresden, group Dr. Leonhardt.)
Researchers at the Institute of Polymer Research Dresden have tackled the task to adapt conventional plastics processing technologies in extruders to the manufacture of composites of polymers and carbon nanotubes. By now, such composites have been produced only in very small amounts in laboratory - their manufacture by conventional machinery can make them highly interesting for industrial applications. The researchers have successfully optimized the mixing conditions and the use of additives. As a result, the addition of only 1 weight% of multiwalled carbon nanotubes leads to antistatic properties, addition of 2 weight% yields conductivity. The effects have been demonstrated for polycarbonate. To bring about the same effects by filling with carbon black, about 10 to 20 weight% of filler would be necessary, and other material properties would considerably deteriorate.
Contact for more detailed information:
Institut für Polymerforschung Dresden e.V.
Hohe Straße 6, 01069 Dresden, Germany
Dr. Petra Pötschke
Phone +49 351 4658 395