PREPERM® product family contains dielectric plastics with extremely low loss and tailored dielectric properties. Dielectric thermoplastic PREPERM® materials offer substantial benefits in design flexibility and manufacturing. They can be easily mass-processed with standard thermoplastic manufacturing equipment in extrusion or injection molding process. Compared to commonly used thermoset processing methods, these processes lead to lower manufacturing costs due to faster cycle times and lower material scrap rate.
All thermoplastic materials perform very well in mass manufacturing. But unfortunately they are not optimized for high frequency applications and the dielectric properties are typically poorly characterized. The dielectric properties for standard plastics are usually given only at 50 Hz and this does not give any proof of performance at 1 GHz or higher frequencies.
For PREPERM® the dielectric measurement data is available even up to 250GHz. The data proves that the dielectric constant of PREPERM® is stable and not dependent on frequency level. RF-designers are able to choose right dielectric constant without large safety margins or need of trial-and-error and estimation.
Chemical structure of the material has impact on the dielectric properties. Polar materials such as polyamides and polyesters show significantly higher dielectric losses than their non-polar counterparts (polyethylene, polypropylene). Also additives and moisture sensitivity in different materials can change the dielectric properties significantly.