Why is white silicone adhesive sealant prone to yellowing?

Ketoxime crosslinking agents, aminosilane type tackifiers, and catalysts contained in ketone free aliphatic silica gel may undergo surface yellowing due to the oxidation of amino acids or some chemical reactions of the catalyst under long-term ultraviolet light irradiation or high temperatures above 8OC. To improve the yellowing phenomenon, special formulations are required, such as solar silica gel, which has good resistance to yellowing. Without complete solidification of dealcoholized silica gel, the titanate catalyst that is not involved in the reaction will display its yellow color under heating conditions, causing the colloid to turn yellow.