Description

Ultranox 626 is a high-performance, sterically hindered phenolic antioxidant widely recognized for its exceptional stability and effectiveness. This compound is critical for protecting polymers and other organic materials from thermal and oxidative degradation during processing and long-term service. It is an essential additive for manufacturers in the plastics, synthetic fiber, and rubber industries seeking to enhance product durability and lifespan.

Application

• Polymer Stabilization: Primary antioxidant for polyolefins (PP, HDPE, LDPE), polystyrene, and engineering plastics to prevent thermal oxidation during extrusion and molding.
• Synthetic Fibers: Protects polypropylene and polyester fibers from strength loss and color degradation caused by heat and light exposure.
• Rubber & Elastomers: Used in SBR, polybutadiene, and other synthetic rubbers to maintain elasticity and prevent cracking.
• Adhesives & Sealants: Extends the shelf life and performance stability of hot-melt and reactive adhesive formulations.
• Lubricants & Fuels: Acts as an antioxidant additive in industrial lubricants and fuels to inhibit sludge formation and viscosity increase.
• Food Contact Materials: Employed in compliant polymer formulations for packaging where approved, to prevent polymer breakdown.

Basic Information

Product Name	Ultranox 626
CAS No.	26741-53-7
Molecular Formula	C41H60O6P2
Molecular Weight	710.86 g/mol
Synonyms	Bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite; Pentaerythritol bis(2,4-di-tert-butylphenyl) phosphite; Phosphite antioxidant 626; Antioxidant 626; ADK STAB PEP-36; Irgafos 126; Doverphos S-9228; Ethanox 398; Hostanox PAR 24; Ultranox 626A
EINECS	247-952-5

Quality Control

Our production of Ultranox 626 adheres to stringent quality management protocols to ensure batch-to-batch consistency and high purity. Each lot is analyzed against comprehensive specifications, including assay, melting point, and key impurity profiles. A Certificate of Analysis (COA) detailing the 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, and well-ventilated area at room temperature (15-25°C). This product is hygroscopic (moisture-sensitive); keep the original container tightly sealed when not in use to minimize exposure to atmospheric humidity.

Specification

Item	Specification
Appearance	White crystalline powder
Identification (IR)	Conforms
Assay (HPLC)	≥ 98.0 %
Melting Point	160 - 175 °C
Acidity (as H3PO4)	≤ 0.1 %
Volatile Matter	≤ 0.5 %
Solution Color (APHA)	≤ 50

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