Description

Tris(Biphenyl-4-Yl) Phosphite is a specialized organophosphorus compound widely utilized as a high-performance stabilizer and antioxidant in polymer chemistry. Its primary value lies in its ability to effectively inhibit thermal and oxidative degradation, thereby extending the service life and maintaining the physical properties of sensitive materials. This product is essential for manufacturers in the plastics, synthetic rubber, and specialty chemical industries seeking to enhance the durability of their formulations.

Application

• Primary antioxidant and processing stabilizer for engineering plastics such as polycarbonate (PC), polyamides (PA), and polyesters (PET, PBT).
• Heat stabilizer in synthetic rubber production to prevent cross-linking and maintain elasticity during processing and use.
• Additive in adhesive and sealant formulations to improve resistance to thermal aging and environmental stress.
• Stabilizing component in specialty lubricants and hydraulic fluids to prevent oxidation and viscosity breakdown.
• Intermediate in the synthesis of more complex phosphite-based antioxidants and ligands for catalytic systems.
• Protective agent for polyolefins (e.g., PP, PE) in combination with other stabilizers for synergistic effects.

Basic Information

Product Name	Tris(Biphenyl-4-Yl) Phosphite
CAS No.	25963-45-5
Molecular Formula	C36H27O3P
Molecular Weight	538.57 g/mol
Synonyms	Tris(4-phenylphenyl) phosphite; Phosphorous acid, tris(4-biphenylyl) ester; Tris(p-phenylphenyl) phosphite; 4,4',4''-Phosphorous acid tris(biphenyl) ester; Tris(4-biphenylyl) phosphite; Antioxidant P-EPQ (related commercial grade); Biphenyl-4-yl phosphite (tris-); P,P,P-Tris(1,1'-biphenyl-4-yl) phosphite
EINECS	Contact for details

Quality Control

Our Tris(Biphenyl-4-Yl) Phosphite is manufactured under a strict quality management system. Each batch undergoes comprehensive analytical testing, including assay by HPLC, identification by FT-IR, and control of key impurities, to ensure consistent performance and high purity suitable for industrial applications. Certificates of Analysis (COA) documenting all relevant specifications are available upon request.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area at room temperature (15-25°C) under an inert atmosphere (e.g., nitrogen) to minimize oxidation. Keep away from strong oxidizing agents and heat sources.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0 %
Melting Point	95 - 105 °C
Loss on Drying	≤ 0.5 %
Heavy Metals (as Pb)	≤ 10 ppm

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.