Phosphites are secondary antioxidants that function by the decomposition of hydroperoxide intermediates in the oxidation process. They most effective at high temperatures and provide excellent protection against degradation during melt processing operations. As processing stabilizers, phosphites serve to minimize changes in melt viscosity and reduce discoloration. Some products (such as PEP-36A) also contribute to the long-term thermal stability and light stability of plastics.
Combinations of phosphites with hindered phenols often show a strongly synergistic performance. These systems represent the state-of-the-art for the melt process stabilization of many types of plastics.
Amfine offers a diverse range of solid and liquid phosphite process stabilizers for plastics.