What are the reasons for silicone household items turning yellow?

As for why silicone rubber products turn yellow, in fact, silicone yellowing is not its essence. Silicone rubber raw materials are composed of hundreds of thousands of molecular crystals, and adding different components can change their composition freely. Therefore, even if there are hundreds of thousands of molecular chains that have not undergone chemical reactions, they will still turn yellow due to external obstacles such as vulcanizing agents, raw materials, anti yellowing agents, etc.

As for silicone vulcanization, most silicone rubber product manufacturers use ordinary vulcanizing agents, which can be used in many products. When used as high transparency or semi transparent products, white often appears yellow when it is transparent. Therefore, many manufacturers will use anti yellowing vulcanizing agents and add anti yellowing agents for high transparency and semi transparency products, which will not cause discoloration. It can be guaranteed that there will be no color change during the secondary odor vulcanization process in high-temperature vulcanization production, and the product will not undergo color change after long-term use.

In addition, there are certain factors in terms of raw materials. Generally, transparent silicone rubber raw materials are mainly reinforced with white carbon black, and the amount of white carbon black used is lower in material cost and has different performance adjustments. Therefore, while improving other properties, the anti yellowing effect will also be affected. Therefore, as the material itself changes, it is more affected by the quality of the material itself.

Another reason is that transparent silicone rubber products are not preheated during use, resulting in yellowing of ordinary precipitation method silicone rubber. Therefore, transparent silicone rubber products may have some yellowing effects, and it is recommended not to expose them to prolonged sunlight or acidic or alkaline liquids.