Description

Tetraphenyl Dipropyleneglycile Diphosphite (CAS 65146-74-9) is a high-performance organophosphite antioxidant and stabilizer. This compound is critical for preventing oxidative degradation and maintaining the physical properties of polymers during high-temperature processing and long-term use. It is an essential additive for manufacturers in the plastics, synthetic rubber, and specialty chemical industries seeking to enhance product durability and performance.

Application

• Primary antioxidant and process stabilizer for polyolefins (PP, PE) and engineering plastics.
• Synergistic component in stabilizer packages for PVC, polycarbonates, and ABS to prevent yellowing and embrittlement.
• Protection of synthetic rubbers and elastomers against heat aging and oxidation.
• Stabilization of adhesives, sealants, and lubricants to extend service life.
• Used in the production of masterbatches and polymer concentrates for consistent additive dispersion.
• Potential application as an intermediate in the synthesis of other specialty phosphite compounds.

Basic Information

Product Name	Tetraphenyl Dipropyleneglycile Diphosphite
CAS No.	65146-74-9
Molecular Formula	C42H44O8P2
Molecular Weight	738.72 g/mol
Synonyms	Tetraphenyl Di(propylene glycol) Diphosphite; Dipropylene Glycol Tetraphenyl Diphosphite; Phosphorous Acid, Tetraphenyl Ester with Dipropylene Glycol; Weston 618; Antioxidant 618; Hostanox PAR 618; Irgafos P-EPQ (related phosphonite); Polygard HR (related blend); 6-Octadecyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, 3,9-bis(2,4-di-tert-butylphenoxy)- (common mis-assignment check)
EINECS	Contact for details

Quality Control

Our production of Tetraphenyl Dipropyleneglycile Diphosphite adheres to stringent quality management protocols. Every batch is tested to ensure it meets precise specifications for purity, color, and hydrolytic stability, which are critical for consistent polymer performance. A comprehensive Certificate of Analysis (COA) detailing assay, impurity profile, and physical properties is provided with each shipment to guarantee traceability and compliance with your quality standards.

Storage

Preserve in a tightly closed container, protected from light. This material is hygroscopic (moisture-sensitive). Store in a cool, dry, well-ventilated area at room temperature (15-25°C). Keep the container tightly sealed under a dry, inert atmosphere (e.g., nitrogen) to prevent moisture absorption and hydrolysis. Isolate from strong oxidizing agents.

Specification

Item	Specification
Appearance	White to off-white crystalline powder or flakes
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0 %
Acidity (as H3PO4)	≤ 0.1 %
Hydrolyzable Chloride	≤ 50 ppm
Melting Point	95 - 105 °C
Loss on Drying	≤ 0.5 %
Solution Color (APHA)	≤ 50

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