To produce high-hardness silicone foam material with a Shore A hardness of 70 to 80, merely adding fillers is not enough; the vinyl content must be increased. Generally, as the amount of vinyl silicone oil increases, the hardness of the rubber compound also rises accordingly. The crosslinking points of unbonded silicone rubber are dispersed and evenly distributed. Due to the zipper effect, its tear resistance is relatively poor. Once a vulcanized product is torn, it will crack all the way through. After the addition of Curing agent an unbalanced concentrated cross-linking occurs, which disperses the stress and significantly enhances the tear strength of silicone products.
Hydrogen-containing silicone oil can be used as a crosslinking agent for addition-cured high-temperature vulcanized silicone rubber. In addition, hydrogen-containing silicone oil molecules contain active oxygen that can act as a reducing agent, which can effectively prevent impurities in the rubber compound from oxidizing and turning yellow. Therefore, it is called an anti-yellowing agent.