Some Aspects on Treeing Phenomena in Filled Epoxy Resin under Artificial Tropical Condition

抄録

The experiments of moisture absorption and diffusion as well as treeing were performed under artificial tropical condition which epoxy resin specimen mixed with fillers. The results highlighted that even if the moisture absorption of specimen dipped into distilled water would be faster than that of exposed to humid environment, finally each of these conditions brought the similar effect to the treeing phenomena. Although tree inception voltage decreased with introducing silica fillers, the fillers prevented the growth of the tree. Moisture accelerated the tree propagation. It suggested that moisture would weaken the electric strength of the resin, leading to the acceleration of tree propagation. In addition, it was found in the filled specimen that the interface easily splits when moisture was introduced. However, even when the specimen contained moisture, it is seen that the filler still suppresses the tree propagation.