Description

Irgafos 38 is a high-performance, hydrolytically stable organophosphite antioxidant widely used to protect polymers from thermal degradation during processing and in long-term service. Its primary value lies in its exceptional ability to prevent molecular weight loss and maintain the physical properties of sensitive polymers, thereby extending product lifespan and enhancing performance reliability. This additive is essential for manufacturers in the plastics, synthetic fiber, and specialty polymer industries who require robust stabilization for demanding applications. The compound is identified by CAS NO 145650-60-8.

Application

• Primary antioxidant and process stabilizer for polyesters (PET, PBT) and polyamides (Nylon 6, Nylon 66).
• Critical component in stabilization packages for engineering plastics used in automotive, electrical, and electronic components.
• Protection of synthetic fibers during high-temperature melt spinning and extrusion processes.
• Stabilization of polycarbonate (PC) and PC blends against thermal yellowing and degradation.
• Use in hot-melt adhesives and other specialty polymer formulations requiring high-temperature stability.
• Co-stabilizer in systems with phenolic antioxidants to provide synergistic protection for a wide range of polyolefins.

Basic Information

Product Name	Irgafos 38
CAS No.	145650-60-8
Molecular Formula	C42H63O3P
Molecular Weight	646.9 g/mol
Synonyms	Bis(2,4-dicumylphenyl) pentaerythritol diphosphite; Pentaerythritol bis(2,4-dicumylphenyl) phosphite; Irgafos® 38; Doverphos® S-9228; Ultranox® 626; Phosphite stabilizer 38; Antioxidant 38; CAS 145650-60-8
EINECS	Contact for details

Quality Control

Our Irgafos 38 is manufactured under a strict quality management system to ensure batch-to-batch consistency and high purity. Each lot is tested against rigorous internal specifications, which typically include assay, color, melting point, and key impurity profiles. A Certificate of Analysis (COA) detailing all test results is provided with every shipment. Our quality commitment supports compliance with relevant global standards for polymer additives.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). This product is hygroscopic (moisture-sensitive); the original container must be kept tightly sealed after opening to minimize exposure to atmospheric moisture.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to reference spectrum
Assay (HPLC)	≥ 98.0 %
Melting Point	75 - 95 °C
Acidity (Titration)	≤ 0.1 mg KOH/g
Volatile Matter	≤ 0.5 %

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