[Antioxidant supply and sales] Application and dosage of antioxidants in various plastics

Antioxidants are a class of chemicals that, when present in only a small amount in a polymer system, can delay or inhibit the oxidation process of the polymer, thus Prevents the aging of polymers and extends their service life, also known as “anti-aging agents”. Antioxidants can be divided into main antioxidants, auxiliary antioxidants and metal antioxidants. Auxiliary antioxidants can be divided into phosphorus antioxidants, thioether antioxidants, and metal purifiers.

The following will help you understand the application and dosage of antioxidants in various plastics:

1. Application in polypropylene: p>

Under normal circumstances, the processing temperature of polypropylene is 220-280°C. If antioxidants are not added, thermal degradation will occur at the processing temperature, causing the melt index to increase. The antioxidant systems commonly used in industry are mainly phenols with higher relative molecular weight, such as 330, 1010, 1076, etc. The dosage is 0.05~0.25%, often used together with calcium stearate.

2. Application in polyethylene:

High molecular weight hindered phenols, such as antioxidants CA, 330, 1010, 1076, etc. Antioxidant 1076 is generally used in high-density polyethylene. If the processing temperature is very high, it is recommended to choose 1010 and phosphoric acid antioxidants. For chemically cross-linked polyethylene, thiobisphenols and polymerized quinoline dioxide derivatives can be used. Dosage 0.1~0.25.

3. Application in styrenic plastics:

Polystyrene is sensitive to photo-oxidation. After oxidation, the product will appear yellowing and brittle. The use of 3-(3,5-di-tert-butyl-4-hydroxybenzopropionic acid) octadecyl not only has antioxidant effects, but also has anti-photooxidation properties. effect. If an appropriate amount of UV absorber is added, the synergistic effect will be better. Dosage 0.1~0.2%.

4. Application in ABS resin;

Phosphite and phenolic antioxidants can be used together, 1076, 1010, 2246, 246. Or DLTP (thiodithiodiphosphate) can be added. Dilauryl propionate), TNP (trinonylphenyl phosphite), etc.