Description

Dioctadecyl Phenyl Phosphite is a high-performance organophosphite antioxidant and secondary stabilizer. This compound is valued for its excellent ability to prevent thermal and oxidative degradation in polymers, thereby extending material lifespan and maintaining performance. It is a critical additive for manufacturers in the plastics, synthetic fiber, and rubber industries seeking to enhance the durability and color stability of their products under processing and end-use conditions.

Application

Dioctadecyl Phenyl Phosphite serves as a highly effective processing and long-term stabilizer across multiple industrial sectors. Its primary applications include:

• Polymer Stabilization: As a secondary antioxidant and metal deactivator in polyolefins (PP, PE), polyesters, and engineering plastics to prevent thermal degradation during extrusion and molding.
• Color Protection: Inhibiting color formation and maintaining clarity in transparent and pigmented polymer formulations.
• Synergistic Blends: Used in combination with primary phenolic antioxidants (e.g., Irganox, BHT) to provide comprehensive stabilization packages with enhanced efficacy.
• Rubber Industry: Protecting synthetic rubbers from heat aging and preserving elastomeric properties.
• Adhesives & Coatings: Improving the thermal-oxidative stability of hot-melt adhesives and various polymer-based coating systems.
• Fiber Production: Stabilizing synthetic fibers like polypropylene during high-temperature spinning processes.

Basic Information

Product Name	Dioctadecyl Phenyl Phosphite
CAS No.	68123-02-4
Molecular Formula	C54H115O3P
Molecular Weight	843.5 g/mol
Synonyms	Bis(octadecyl) phenyl phosphite; Distearyl phenyl phosphite; Phenyl dioctadecyl phosphite; Phosphorous acid, phenyl bis(octadecyl) ester; Antioxidant 619; Weston 618; Hostanox PAR 24; Doverphos S-680; ADK STAB 329; Irgafos 168 (Note: Irgafos 168 is tris(2,4-di-tert-butylphenyl) phosphite, a related but distinct compound often listed in searches).
EINECS	268-526-5

Quality Control

Our Dioctadecyl Phenyl Phosphite is manufactured under a strict quality management system. Each batch undergoes rigorous analytical testing to ensure it meets precise specifications for purity, color, and performance. Certificates of Analysis (COA) documenting key parameters are available for every shipment upon request, providing full traceability and compliance assurance for your quality protocols.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area at room temperature (15-25°C). This product is hygroscopic (moisture-sensitive); containers must be kept tightly sealed to prevent absorption of atmospheric moisture, which can affect product performance.

Specification

Item	Specification
Appearance	White to off-white flakes or powder
Identification (IR)	Conforms to standard
Assay (HPLC)	≥ 98.0 %
Acidity (as H3PO4)	≤ 0.1 %
Color (APHA)	≤ 50
Melting Point	45 - 55 °C
Phosphorus Content	3.6 - 3.8 %

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