What other low dielectric constant materials are suitable for insulation layers?

Based on the previous discussion about the selection of low dielectric constant materials for the hot runner conductor insulation and reducing the distributed capacitance to alleviate the low pass filtering effect, in addition to the previously mentioned PTFE, FEP, PFA and PI, the following low dielectric constant insulation materials are suitable for high temperature hot runner applications:

The dielectric constant of porous polytetrafluoroethylene (ePTFE) is roughly 1.3~1.6, and it has a microporous structure. Its dielectric constant is much lower than that of standard PTFE. It can tolerate temperatures up to 260℃ and may greatly minimize dispersed capacitance.

Polyetheretherketone (PEEK): Dielectric constant around 3.0~3.2, superb mechanical strength, longtime working temperature up to 250℃, wear-resistant and aging-resistant, good for high vibration hot runner use.

Modified silicone rubber: Dielectric constant about 2.5~3.0, wide temperature range (-60℃~250℃), good elasticity, appropriate for intricate wiring scenarios within hot runners.

Polyaryletherketone (PAEK) has a dielectric constant of about 2.9~3.1, long-term temperature resistance above 250℃, and excellent insulation stability, with nearly no dielectric constant drift under long-term high temperature.

These materials are applicable to high-temperature working conditions with hot runners, which can effectively reduce the parasitic distributed capacitance in conductors, diminish the low-pass filtering effect, and avoid thermal shock cracking due to temperature control lag.