Polymer degradation is a complex process often initiated by the formation of unstable hydroperoxides. NINGBO INNO PHARMCHEM CO.,LTD.'s Phosphite Antioxidant 4500 is specifically engineered to tackle this issue, providing a robust defense against oxidative damage. Understanding its mechanism is key to appreciating its value in enhancing polymer stability.

The auto-oxidation of polymers typically involves a free radical chain mechanism. During the propagation stage, polymer radicals react with oxygen to form peroxy radicals, which then abstract hydrogen atoms from the polymer chain, generating hydroperoxides (ROOH) and new polymer radicals. Hydroperoxides are thermally unstable and can decompose into highly reactive alkoxy (RO•) and hydroxyl (•OH) radicals. These radicals can initiate further oxidation chains, leading to chain scission, cross-linking, and ultimately, material failure.

Phosphite antioxidants, like our Phosphite Antioxidant 4500, function as crucial chain-breaking secondary antioxidants. Their primary role is the efficient decomposition of hydroperoxides. The phosphorus atom in the phosphite ester is in a lower oxidation state and readily reacts with hydroperoxides. This reaction converts the unstable hydroperoxide into more stable, non-radical products, such as alcohols, and oxidizes the phosphite to a phosphate.

The chemical reaction can be broadly represented as:

ROOH + P(OR')₃ → ROH + OP(OR')₃

Where P(OR')₃ represents the phosphite antioxidant and OP(OR')₃ represents the oxidized phosphate form. By removing hydroperoxides from the system, Phosphite Antioxidant 4500 effectively interrupts the degradation cycle, preventing the generation of damaging free radicals. This mechanism is fundamental to its ability to provide excellent heat resistance for thermoplastics and hydrolysis resistance.

The high phosphorus content and polymeric nature of Phosphite Antioxidant 4500 contribute to its longevity and effectiveness in high-temperature processing environments. Its ability to synergize with primary antioxidants further amplifies its protective capabilities, leading to improved color retention in plastics and overall enhanced product performance. This scientific basis for its action makes it an indispensable additive for manufacturers seeking to maximize the lifespan and quality of their polymer products.

NINGBO INNO PHARMCHEM CO.,LTD. is proud to offer advanced chemical solutions grounded in scientific understanding. Phosphite Antioxidant 4500 exemplifies our commitment to providing effective and reliable polymer stabilization technologies.