Description

Cyasorb UV-3638 is a high-performance ultraviolet (UV) light absorber and stabilizer, identified by CAS No. 18600-59-4. This compound is critical for protecting polymers and coatings from photodegradation, thereby extending product lifespan and maintaining aesthetic and mechanical properties. It is an essential additive for manufacturers in the plastics, automotive, packaging, and construction industries seeking to enhance the durability of their materials against long-term UV exposure.

Application

• Plastics Stabilization: Primary use in polyolefins (PP, PE), PVC, and engineering plastics to prevent yellowing, embrittlement, and loss of gloss caused by sunlight.
• Automotive Components: Protection for interior and exterior plastic parts, dashboards, bumpers, and trim from UV-induced fading and cracking.
• Coatings and Paints: Incorporated into industrial and automotive coatings to preserve color and film integrity.
• Packaging Films: Used in food and consumer goods packaging to maintain clarity and strength under retail lighting.
• Construction Materials: Stabilizer for synthetic fibers, geomembranes, and outdoor building profiles.
• Adhesives and Sealants: Enhances the weatherability of products used in outdoor applications.

Basic Information

Item	Detail
Product Name	Cyasorb UV-3638
CAS No.	18600-59-4
Molecular Formula	C₂₈H₄₄N₂O₂
Molecular Weight	440.66 g/mol
Synonyms	2,2'-(1,4-Phenylenedimethylene)bis[4,6-bis(1,1-dimethylethyl)phenol]; UV-3638; Bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite (Note: This is a common but incorrect synonym often associated; the correct identity is the phenolic compound); Phenolic antioxidant/light stabilizer; 1,4-Benzenedimethanol, α,α,α',α'-tetramethyl-; Light stabilizer 3638
EINECS	Contact for details

Quality Control

Our Cyasorb UV-3638 is manufactured under a strict quality management system. Every batch undergoes comprehensive analytical testing to ensure it meets precise specifications for identity, purity, and performance. Certificates of Analysis (COA) documenting these results are available upon request 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). Keep away from heat sources and incompatible materials. This product is light-sensitive (store away from light).

Specification

Item	Specification
Appearance	White to off-white powder or crystalline solid
Identification (IR)	Conforms to reference spectrum
Assay (HPLC)	≥ 98.0%
Melting Point	Contact for details
Loss on Drying	≤ 0.5%
Ash Content	≤ 0.1%

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