Description

Phosphorous Acid Tri-n-Octadecyl Ester is a high-purity organophosphorus compound, also known as trioctadecyl phosphite. This specialty chemical serves as a highly effective antioxidant and stabilizer, prized for its ability to protect polymers and other materials from thermal and oxidative degradation. It is a critical additive for manufacturers in the plastics, lubricant, and synthetic fiber industries seeking to enhance product longevity and performance under demanding conditions.

Application

• Polymer Stabilization: Acts as a secondary antioxidant and process stabilizer in polyolefins (PP, PE), PVC, and engineering plastics to prevent chain scission and discoloration during processing and end-use.
• Lubricant & Grease Additive: Used as an anti-wear and extreme pressure (EP) additive in synthetic and mineral-based lubricants and greases, improving thermal stability and reducing oxidation.
• Synthetic Fiber Production: Employed as a stabilizer in the melt spinning process for fibers like polyester and nylon to maintain viscosity and prevent yellowing.
• Rubber Industry: Functions as an antioxidant in synthetic rubber formulations, protecting against heat aging and maintaining elastomeric properties.
• Adhesive & Sealant Formulations: Enhances the shelf-life and thermal stability of hot-melt and reactive adhesive systems.
• Fuel & Oil Additive Precursor: Serves as an intermediate in the synthesis of other phosphorus-based additives for fuels and lubricating oils.

Basic Information

Product Name	Phosphorous Acid Tri-n-Octadecyl Ester
CAS No.	2082-80-6
Molecular Formula	C54H111O3P
Molecular Weight	839.43 g/mol
Synonyms	Trioctadecyl Phosphite; Tri-n-Octadecyl Phosphite; Phosphorous Acid Trioctadecyl Ester; n-Octadecyl Alcohol Phosphite (3:1); Stearyl Phosphite (approx.); Tris(octadecyl) Phosphite; Tris(stearyl) Phosphite; Antioxidant TSP
EINECS	218-212-0

Quality Control

Our Phosphorous Acid Tri-n-Octadecyl Ester is manufactured under a strict quality management system. Each batch undergoes rigorous analytical testing to ensure consistent purity, performance, and compliance with industry specifications. Certificates of Analysis (COA) detailing assay, identity, and impurity profiles are available for every shipment upon request.

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 material is hygroscopic (moisture-sensitive) and easily oxidized; for long-term storage, consider maintaining under an inert atmosphere such as nitrogen. Keep away from strong oxidizing agents.

Specification

Item	Specification
Appearance	White to off-white waxy solid / flakes
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 97.0%
Melting Point	Contact for details
Acid Value	≤ 1.0 mg KOH/g
Phosphorus Content	Contact for details
Heavy Metals (as Pb)	< 10 ppm
Loss on Drying	< 0.5%

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