Method of manufacturing an electrically conductive thermoplastic material

Abstract

Abstract A method of manufacturing a highly electrically conductive plastic material from thermoplastic resin and carbon fill through a two-screw mixer having a screw length of more than twenty times the screw diameter involves continuously inserting a thermoplastic resin into a first zone of the two-screw mixer and compacting and preheating the thermoplastic resin. The resin is then passed into a second zone where it is kneaded and plastified. A particulate carbon fill is continuously inserted into a third zone with the fill constituting 30 to 50% by weight of the mixture and being dispersed in said resin within the third zone. The speed of rotation of the two screw mixer lies in the range between 150 to 250 RPM and the temperatures of the zones lie within the range of 165 DEG C. to 300 DEG C. After passage through the various zones, the mixture is removed via an outlet of an extrusion head. A copolymer propylene and ethylene forms the thermoplastic resin in the carbon black and the carbon black constitutes the particular carbon fill. A fill of not more than 10% by weight carbon fibers may be inserted at one of the zones. Further, a fourth zone may follow the third zone with the method further including the step of degasing the mixture at a pressure lying in the range of atmospheric pressure to a few millibars at the fourth zone.

Inventors

• 👤 Rene Delphin
• 👤 Bernard Regnaut

Bibliographic Details