Evaluation on Applicability to Electrical Insulating Material of Hydrocarbon‐Based Thermosetting Resin

SUMMARY This paper deals with dielectric properties of hydrocarbon‐based thermosetting resin to evaluate the applicability to electrical insulating materials. Moreover, higher withstand voltage, lower dielectric constant, and lower moisture absorption are required for the electrical insulating materials. One of the candidate polymer materials satisfying such demands is hydrocarbon‐based thermosetting resin, that is, polydicyclopentadiene (P‐DCP) and polytricyclopentadiene (P‐TCP). We measured the dielectric properties such as dielectric constant, dielectric loss, volume resistivity, and breakdown strength (BDS), and other properties such as moisture absorption, viscosity, mechanical strength, glass transition temperature, and coefficient of linear expansion of those specimens. It was found from the results in particular that P‐DCP and P‐TCP have the lower dielectric constant and the lower moisture absorption as compared with epoxy resin, while the volume resistivity and the BDS of P‐DCP and P‐TCP are not different to those of epoxy resin. As a result, it is elucidated that two kinds of hydrocarbon‐based thermosetting resin have a potential for application to an electrical insulating material.