1, because the high temperature silicone tube in the production did not control the mold temperature and vulcanization time.

2, the use of silicone rubber hydroxyl content is too much, high temperature aging.

3, the amount of catalyst used, or the quality of the catalyst used is not qualified, resulting in the yellow phenomenon of high-temperature silicone tube.

4, add too much internal release agent and zinc stearate, the iron content inside is too high, resulting in high temperature resistant silicone tube surface yellow.