- Used to prevent thermal degradation and provide long term stability
- Inhibit ‘oxidation’ (i.e. degradation)
- Are ‘cheap’ insurance for multiple pass materials
Antioxidants are generally divided into primary and secondary categories. Each category has a specific function in polymer stabilization.
Primary Antioxidants are used to protect the finished product. This type of stabilization ensures performance over the life of the finished good. The typical chemistry for a primary antioxidant is phenolic-based.
Secondary Antioxidants are used as a process stabilizer. They are an effective way to protect the polymer during processing, especially when the polymer undergoes multiple heat histories. Typical chemistries employed include phosphites or thioesters.
Primary/Secondary Blends – Primary and secondary antioxidants are often used in a combination. When used this way, the polymer is protected both during the processing step and throughout its service life.
To avoid pinking, proper selection of the AO and co-additives is required.
For more information on Ampacet’s Antioxidant Masterbatches, please contact your local Ampacet representative or complete our product inquiry form.