SI Group Weston™ Phosphite Antioxidants
Innovative Secondary Antioxidants
Secondary antioxidants act as peroxide decomposers by reducing the hydroperoxide to alcohol and eliminating the source causing the chain branching. Phosphite secondary antioxidants offer effective performance during the melt phase, improve color retention, and work during the melt stabilization stage.
The SI Group WESTON™ portfolio comprises high-purity solid and liquid phosphite antioxidant and liquid phosphite ester additives. These SI Group additives are designed to function as secondary antioxidants while synergizing with primary antioxidants, such as hindered phenols. WESTON™ phosphite antioxidants are suitable for various plastic and elastomer resins that require color, processing, and thermal stability.
Explore the SI Group portfolio of WESTON™ phosphite antioxidant grades below, and if you are unsure which grade works best for your formulation, talk to an expert today.
| Name | Type | Key Properties | Documentation |
|---|---|---|---|
| WESTON™ 398 | Liquid Phosphite | Versatile phosphite stabilizer improves color, processing stability, and end use of various plastics, such as HDPE, LLDPE, SBR, ABS, PVC, and more. | |
| WESTON™ 399 | Liquid Phosphite | Versatile phosphite stabilizer improves color, processing stability, and end use of various plastics and elastomers; similar to WESTON™ 398 but with food contact approval. | |
| WESTON™ 430 | Liquid Phosphite Ester | Specialty alkyl phosphite antioxidant effectively stabilizes heat, color, and viscosity in various polymer resins. | |
| WESTON™ 439 | Liquid Phosphite Ester | Phosphite ester antioxidant designed to improve color, clarity, and light stability of PVC and vinyl chloride copolymers. | |
| WESTON™ 618F | Solid Phosphite | Highly effective, phosphite-based color and molecular weight stabilizer for polymers, elastomers, and adhesives. | |
| WESTON™ 619F | Solid Phosphite | Highly effective, phosphite-based color and molecular weight stabilizer for polymers, elastomers, and adhesives; similar to WESTON™ 618F but with improved hydrolytic stability. | |
| WESTON™ 705 | Liquid Phosphite | Nonylphenol-free liquid phosphite antioxidant with broad FDA approval designed as a drop-in replacement for TNPP with a 20% lower loading rate. | |
| WESTON™ 705T | Liquid Phosphite | Nonylphenol-free phosphite antioxidant additive designed as a drop-in replacement for TNPP with a 20% lower loading rate; like WESTON™ 705 but with improved hydrostability. | |
| WESTON™ DPDP | Liquid Phosphite Ester | Alkyl aryl phosphite ester antioxidant provides color and processing stability in polymers that do not require food contact approvals. | |
| WESTON™ DPP | Liquid Phosphite Ester | Diaryl phosphite ester antioxidant with a high phosphorus content and relatively low molecular weight; improve color and light stability in polymers that do not require food contact approval. | |
| WESTON™ PDDP | Liquid Phosphite Ester | Alkyl aryl phosphite ester antioxidant provides color and processing stability in polymers that do not require food contact approval; similar to WESTON™ DPDP but with higher molecular weight and lower phosphorus content. | |
| WESTON™ TDP | Liquid Phosphite Ester | Trialkyl phosphite ester antioxidant functions as a secondary stabilizer in various polymers that do not require food contact. | |
| WESTON™ TLP | Liquid Phosphite Ester | Trialkyl phosphite ester antioxidant functions as a sulfur deactivator and improves antifriction and antiwear characteristics in lubricants. | |
| WESTON™ TNPP | Liquid Phosphite | Versatile phosphite stabilizer improves color, processing stability, and end use of various polymers; similar to WESTON™ 399 but with a higher flash point. | |
| WESTON™ TPP | Liquid Phosphite Ester | Versatile aryl phosphite ester antioxidant that regulates viscosity, improves color, and prevents scorch in a variety of polymers. |
