Experimental investigation of technological conditions and temperature distribution in rubber material during microwave vulcanization process

Abstract

The optical fiber temperature online monitor and the optical fiber temperature sensor were employed to measure internal temperature of sheet rubber during the microwave vulcanization process, and the infrared thermal imager was utilized to measure the temperature at the surfaces of sheet rubber. First of all, in the contrast experiment, the setting principle of microwave power was explored, the experimental results demonstrated that the rate of temperature rising within sheet rubber was higher by using high microwave power during microwave heating process, and the proper vulcanization temperature was obtained by using high and low microwave power alternately. Experimental results indicated that the output of heat during vulcanization reaction promoted the rate of temperature rising of the temperature measuring point, during the microwave vulcanization process of all experimental sheet rubber, the rate of temperature rising in the central zone of sheet rubber was higher than the rate of temperature rising in the marginal zone, the temperature distribution at the surfaces of sheet rubber presented non-uniformity, the maximum of temperature converged on the central zone of sheet rubber, and results manifested that the distribution of electric field was uneven in heating chamber. Due to the existence of heat transfer phenomenon, the area of the higher temperature zone of sheet rubber expanded gradually from the central zone to the marginal zone.