Hello! Welcome to visit Dongguan Guangmei Silicon Rubber Products Co., Ltd. Official website!
※ Chinese ※ English ※ Contact us
Product Categories

Business Consulting


What are the reasons for the yellowing of silicone products?

Normally, plastic products will not be yellowed for a few years. However, in production, some of the freshly baked transparent silicone products look yellowish and appear to have changed color. Why do silicone products yellow?
First, vulcanizing agents:
1. Curing agent performance is divided into ordinary type and yellow resistance. Its application scope has the following two aspects:
2. Common non-yellowing vulcanizing agents are used in non-exposed, non-exposed silicone products that can be used for darker or less demanding colors.
3. Anti-yellowing vulcanizing agent is used in products that need to be exposed, lighter in color and brighter, and require higher color.
Second, the process:
When silicone products are molded, the yellow color of the silicone products after molding is mainly problematic:
1. Mold temperature is too high;
2. Vulcanization time is too long;
3. After the second vulcanization
Third, the quality of raw materials itself is too bad:
Sometimes we add anti-yellowing vulcanizing agent in the rubber compound, but the silicone product still looks yellowish after it is molded. It may be the raw material's anti-yellowing ability is too bad. The raw material's anti-yellowing raw material's suggestion is direct. Refueling.
There are several reasons for the yellowing of silicone rubber:
First, the trace metal elements and NO contained in raw materials and additives for the production of silicone rubber are caused;
The second is the decomposition of dialkyl peroxide to produce acetone, resulting in the condensation of α-hydroxybutyraldehyde, dehydration, resulting in the formation of conjugated compounds;
Third, the pH value of silica affects the yellowing of the silicone rubber. When the pH value of the silica is acidic, the silicone rubber can be significantly yellowed. The degree of yellowing is inversely proportional to the pH value. When the pH is less than 5%, this is the case. This kind of inverse proportional relationship is even more pronounced.
How to improve the yellowing of silicone rubber:
1. Adding an anti-yellowing paste double 2,5 vulcanizing agent with a high amount of hydrogen silicone oil to improve the anti-yellowing effect of silicone rubber;
2. The use of silica with relatively high purity is selected;
3. The addition of a silica-magnesium nano-permanent enhancer can improve the advantages of transparent silica gel, such as easy water absorption, whitening and yellowing, and can increase the transparency of ordinary precipitation adhesives to more than 90%.

Dongguan Guangmei Silicon Rubber Products Co., Ltd.Variety | Stock foot | Customized drawingsFocus on the processing and sales of silicone rubber products

重庆快乐十分 广东快乐十分 重庆快乐十分 广东快乐十分 重庆快乐十分 广东快乐十分 广东快乐十分 重庆快乐十分 广东快乐十分 重庆快乐十分