Dielectric loss of high‐density polyethylene below 4.2°K

Abstract Drawing of oxidized high‐density polyethylene (HDPE) and subsequent annealing greatly reduce the low‐temperature dielectric loss when the electric field is applied perpendicular to the draw direction. This supports our model ( J. Polym. Sci. Polym. Phys. Ed. , 15 , 43 (1977)) of the proton moving parallel to the c axis of the PE crystal. A particular antioxidant (Ionox 330) in unoxidized HDPE induces a dielectric loss with a frequency and temperature dependence which differs from that for the loss in oxidized HDPE. The antioxidant loss seems to be an overlapping of tunneling and a thermal activation process. The possibility that the hydroperoxide group in the PE crystal is the origin of the loss in oxidized HDPE was theoretically examined in a manner similar to that used for the hydroxyl group in the previous paper. Results suggest that the hydroperoxide group is less probable than hydroxyl as the origin of the low‐frequency loss in HDPE.