Description

Docosamethylcycloundecasiloxane is a high-purity, cyclic siloxane oligomer, specifically a D22 cyclic compound, with the CAS registry number 18766-38-6. This specialty organosilicon chemical serves as a critical intermediate and performance additive, valued for its unique combination of thermal stability, low volatility, and hydrophobic character. It is essential for manufacturers and R&D facilities in the personal care, electronics, and advanced materials sectors seeking to enhance product performance and process reliability.

Application

• Personal Care & Cosmetics: Acts as a premium emollient and conditioning agent in antiperspirants, deodorants, and skin care formulations, providing a smooth, non-greasy feel and improved spreadability.
• Silicone Fluids & Elastomers: Serves as a key intermediate or modifier in the synthesis of specialty silicone oils, gels, and high-consistency rubber (HCR), influencing viscosity and crosslink density.
• Release Coatings & Molding: Used in formulations for industrial release agents and mold-making applications, facilitating clean part separation and surface finish.
• Electronics & Electrical: Employed as a dielectric fluid or heat transfer medium in specialized electronic encapsulants and thermal management systems.
• Surface Treatment & Textiles: Imparts durable water repellency (DWR) and stain resistance to fabrics, leather, and various substrates.
• Lubricants & Greases: Functions as a base fluid or additive in high-performance synthetic lubricants requiring extreme temperature stability and low pour points.
• Pharmaceutical & Medical Devices: Utilized as an inert excipient or processing aid in controlled-release drug delivery systems and biocompatible device coatings.
• Research & Development: A valuable building block for synthesizing novel siloxane-based polymers, dendrimers, and hybrid organic-inorganic materials.

Basic Information

Product Name	Docosamethylcycloundecasiloxane
CAS No.	18766-38-6
Molecular Formula	C22H66O11Si11
Molecular Weight	814.60 g/mol
Synonyms	Cycloundecasiloxane, docosamethyl-; D22 Cyclic; Cyclic Volatile Methyl Siloxane (cVMS) D22; Decamethylcyclopentasiloxane, dimer-related; Undecamer, cyclic; 1,1,3,3,5,5,7,7,9,9,11,11,13,13,15,15,17,17,19,19,21,21-Docosamethyl-1,3,5,7,9,11,13,15,17,19,21-undecaoxacyclodotriacontasileicosane
EINECS	Contact for details

Quality Control

Our Docosamethylcycloundecasiloxane is manufactured under a strict quality management system. Each batch undergoes rigorous analytical testing, including Gas Chromatography (GC) and Nuclear Magnetic Resonance (NMR), to ensure identity, purity, and consistency. Certificates of Analysis (COA) detailing all specifications are provided with every shipment. We adhere to cGMP principles where applicable, and our quality systems are designed to support compliance with global regulatory frameworks such as REACH.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area at a controlled room temperature (15-25°C). Keep away from strong acids, strong bases, and oxidizing agents. For long-term storage under inert atmosphere, please contact us for specific recommendations.

Specification

Item	Specification
Appearance	Colorless to pale yellow clear liquid
Identification (IR)	Conforms to reference spectrum
Assay (GC)	≥ 98.0%
Refractive Index (n20D)	1.395 - 1.405
Density (20°C)	0.95 - 0.99 g/cm³
Water Content (KF)	≤ 0.1%

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