Description

O,O'-Dioctadecylpentaerythritol Bis(Phosphite) is a high-performance organophosphite antioxidant widely used as a stabilizer in polymer processing. Its primary value lies in its ability to effectively prevent thermal degradation and color formation in polymers during high-temperature manufacturing. This compound is essential for producers of polyolefins, engineering plastics, and synthetic rubbers who require long-term material stability and consistent product quality.

Application

• Polymer Stabilization: Acts as a highly effective secondary antioxidant (process stabilizer) in polypropylene (PP) and polyethylene (PE) to prevent thermal degradation during extrusion and molding.
• Color Protection: Inhibits yellowing and discoloration in a wide range of polymers, including ABS, polystyrene, and polycarbonate, ensuring superior aesthetic quality.
• Synergistic Formulations: Used in combination with primary phenolic antioxidants to provide comprehensive stabilization, significantly extending the service life of finished plastic products.
• Adhesives & Sealants: Enhances the thermal-oxidative stability of hot-melt adhesives and synthetic rubber-based sealants.
• Engineering Plastics: Provides critical stabilization for high-temperature processing of engineering resins such as polyamides (nylon) and polyesters (PBT, PET).
• Masterbatch Production: A key additive in color and additive masterbatches, ensuring the stability of the carrier resin and active components.

Basic Information

Product Name	O,O'-Dioctadecylpentaerythritol Bis(Phosphite)
CAS No.	3806-34-6
Molecular Formula	C85H164O6P2
Molecular Weight	1364.10 g/mol
Synonyms	Pentaerythritol Bis(stearyl phosphite); Bis(octadecyl) pentaerythritol diphosphite; Pentaerythrityl bis(stearyl phosphite); Distearyl pentaerythritol diphosphite; DOPP; Weston 618; Antioxidant 618; Hostanox PAR 24; Irgafos 168 (Note: Irgafos 168 is typically tris(2,4-di-tert-butylphenyl) phosphite, but DOPP is sometimes grouped under similar trade categories).
EINECS	223-276-6

Quality Control

Our production of O,O'-Dioctadecylpentaerythritol Bis(Phosphite) adheres to stringent quality management protocols to ensure batch-to-batch consistency and high purity. Each lot is tested against comprehensive specifications, including assay, phosphite content, melting point, and color. A Certificate of Analysis (COA) detailing all test results is provided with every shipment to support your quality assurance and regulatory compliance needs.

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 material is hygroscopic (moisture-sensitive) and easily oxidized; for long-term storage, keeping the container under an inert atmosphere (nitrogen) is recommended to maintain optimal efficacy.

Specification

Item	Specification
Appearance	White to off-white powder or flakes
Identification (IR)	Conforms to structure
Assay (Phosphite Content)	≥ 97.0 %
Melting Point	40 - 50 °C
Acidity (as H3PO4)	≤ 0.1 %
Volatile Matter	≤ 0.5 %
Color (APHA)	≤ 50

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