With Turcon MC1 and Turcon MC2, Trelleborg meets its customers' requirements for conductive plastic sealing materials that can be used effectively and reliably as seals and bearings in dynamic applications. These materials allow designers to use improved PTFE-based sealing geometries and take advantage of their benefits in applications that require electrical conductivity, such as hydraulic systems or electric motors.

The electrically conductive materials Turcon MC1 and Turcon MC2 based on PTFE. © Trelleborg

Pure PTFE is an excellent insulating material and offers a resistance of approx. 2 x 10+17 Ohm-cm. PTFE material mixtures can conduct electricity if conductive fillers are added. These must also bond within the PTFE matrix. Until now, only PTFE-based material mixtures with a carbon filling were conductive above a certain "threshold value". Electrical conductivity was only achieved by chance with these carbon-filled PTFE-based materials. Electrical resistance was not a primary technical requirement. This is where Turcon MC1 and Turcon MC2 differ: Trelleborg developed them specifically for electrical conductivity in dynamic sealing applications and improved their sealing performance for these applications.

Electrically conductive sealing materials are used in important applications:

• A worst-case scenario for aircraft is a lightning strike. However, the static charge generated by the air during flight is less critical. Electrically conductive seals in landing gear, for example, ensure that electricity or static charge is safely dissipated.
• The transfer of an electrical charge across the gap between two components can lead to sparking or stray current in machines and systems, for example in electric motors. This can lead to pitting of appliance parts and carbonization of lubricant or grease. If electrically conductive seals or bearings are used, the system is earthed by creating a direct path between two components, thereby preventing corrosion.
• Signals are sometimes sent directly to or from a sensor in the system. This signal transmission is made possible by the use of electrically conductive seals or bearings, as they create a direct path for the signal. This allows system manufacturers to develop more complex systems using artificial intelligence without the need for additional electrical circuits.