High thermally and electrically conductive plastics

By nature, plastics are not thermally or electrically conductive. However, in certain complex applications such as fuel cells or redow-flow batteries, very high electrical and thermal conductive properties of the materials are required in order to separate reaction gases and cooling media from one another and distribute them in the reaction areas. At the same time, the materials must also be resistant to chemical, thermal and mechanical loads. Only the fulfillment of these requirements guarantees the long-term safe functioning of these applications. With the help of special additives, plastics can be optimised in such a way that they are ideal for such highly specialised and complex applications.

The TECACOMP HTE materials from Ensinger are compounds which have been specifically developed and optimised for these special applications. Their suitability is based on a significantly higher than normal ratio of fillers. This high filling ratio enables a degree of electrical and thermal conductivity which was previously unachiev­able with plastics. At the same time, chemical resistance is also maintained.

The polymers propylene (PP) or polyphenylene sulphide (PPS) are used as the basis for TECACOMP HTE. It is able to cover application temperatures ranging from 60 ° to 200 °C. The materials also work without any problems at ambient temperatures down to -30 °C.

PPS has already proven its superiority over thermosetting plastic binders in HT PEM (high temperature polymer electrolyte membrane) fuel cells. PP compounds are suitable for use in NT-PEM (low-temperature polymer electrolyte membrane) fuel cells as well as in direct methanol fuel cells (DMFC) or redox flow batteries.

To achieve the high electrical and thermal ­val­ues required by these applications, carbon-based fillers such as graphite, carbon black or carbon fibres are mixed with the base polymers for TECACOMP HTE in a ratio of up to 90 % by weight.

Depending on the plastic used, the filler content and the desired component size, the formulations are suitable for processing on hot presses or in injection molding. Therefore, the compounds are available in different versions as powder or granules.