Polymeric products can be degrading due to oxidation by various origins, so that their service life is reduced. Oxidative degradation can lead to discoloration, loss of tensile strength and impact strength, as well as weakening of other physical and mechanical properties of polymers. Oxidative degradation mainly occurs by the formation of free radicals in the polymer structure. These free radicals come from a variety of reasons: the breakdown of polymer chains during processing or mixing, exposure to light and ozone, the remaining of catalysts in the polymer structure, and finally the presence of impurities in the polymer.
Therefore, in order to prevent oxidative degradation, antioxidant additives should be added to the polymeric formulations.
In this regard, Ciba Polymer Kabir has introduced a variety of antioxidant masterbatches based on the first and second type of antioxidants. The low percentage (about 2 to 3% by weight) of these masterbatches reduces the oxidative degradation of the final product and increases their service life. However, the simultaneous use of antioxidant and UV-stabilizer masterbatches has synergistic effect.