For high-temperature vulcanized silicone rubber, two-stage vulcanization is usually required to remove the decomposition residues of the peroxide, while further crosslinking the silicone rubber to obtain the best physical properties. However, in the actual application of silicone rubber, there is a phenomenon of yellowing. The secondary vulcanization will reduce the transparency, directly affect the appearance of the product, and limit its application in the food, medical and solar photovoltaic industries. Researchers have also done a lot of research in this area and have used many anti-yellowing additives.

Regarding the causes of yellowing of silicone rubber, some researchers believe that the trace metal elements contained in the raw materials and added additives for the production of raw rubber for silicone rubber have caused serious yellowing after secondary vulcanization. There are also studies that believe that the decomposition of dialkyl peroxides produces acetone, which results in the condensation and dehydration of α-hydroxybutyraldehyde to form conjugated compounds, which causes yellowing. Some people believe that the pH value of silica is important for controlling silicone rubber. Yellowing has an effect. In addition, during the production of raw rubber, if the catalyst is not removed, it will cause yellowing of the colloid. It is necessary to ensure that the entire process is free of impurities. Therefore, the measures to solve the yellowing of silicone rubber are mainly from raw rubber, additives, white carbon, etc. In addition, the actual production process will also have a certain impact on the yellowing.