A Study on the Tracking Characteristics of Silicone Rubber Degraded by Accelerated UV Exposure

자외선 가속열화에 의한 실리콘 고무의 트래킹 특성 변화에 관한 연구

  • Published : 2000.05.01

Abstract

The tracking characteristics of silicone rubber degraded by accelerated outdoor exposure employing a weather-o-meter were investigated. The tracking test was performed according to ICE Publ.587 method but the concentration of conductive solution was two times higher than IEC standard in order to accelerate the tracking failure. The number of large effective scintillation and the current of high voltage circuit were measured simultaneously. It was shown that the number of effective scintillation had valuable information of the tracking degradation state of silicone rubber, while the average current between electrodes could not provide information enough for diagnosis. Based upon the experimental results, it could be said that the key factor accelerating tracking failure was not Joule heating by current but pyrolysis by burning of silicone rubber, and that reduction of contact angle was due to chain scission which resulted in the free radicals of low molecules.

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References

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