Description

Heptamethyl Cyclotetrasiloxane is a high-purity organosilicon compound, specifically a cyclic siloxane, serving as a crucial intermediate and functional fluid in advanced manufacturing. Its primary value lies in its versatility as a reactive monomer and process aid for synthesizing silicone polymers, oils, and elastomers with tailored properties. This product is essential for industries requiring precise silicone chemistry, including personal care, pharmaceuticals, electronics, and high-performance coatings.

Application

• Silicone Polymer Synthesis: A key reactive intermediate (monomer) for the production of polydimethylsiloxanes (PDMS) and other silicone copolymers.
• Personal Care & Cosmetics: Used as a volatile carrier and emollient in antiperspirants, deodorants, and skin care products, providing a smooth, non-greasy feel.
• Electronics & Semiconductor Manufacturing: Functions as a process fluid or precursor for silicone-based dielectric coatings and protective layers.
• Industrial Lubricants & Release Agents: Employed as a base or additive in specialty lubricants and mold release agents due to its thermal stability and low surface tension.
• Pharmaceutical Intermediates: Serves as a building block in the synthesis of siloxane-based active pharmaceutical ingredients (APIs) and excipients.
• Water Repellents & Surface Treatments: Used to impart hydrophobic properties to textiles, paper, and various materials.

Basic Information

Product Name	Heptamethyl Cyclotetrasiloxane
CAS No.	15721-05-8
Molecular Formula	C7H21O4Si4
Molecular Weight	281.51 g/mol
Synonyms	Octamethylcyclotetrasiloxane, D4; Cyclotetrasiloxane, octamethyl-; 2,2,4,4,6,6,8,8-Octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane; Dodecamethylcyclohexasiloxane (common misnomer, verify context); Octamethyl-cyclotetrasiloxane; OMCTS; Tetramer; D4 Siloxane
EINECS	239-793-3

Quality Control

Our Heptamethyl Cyclotetrasiloxane is manufactured under a strict quality management system. Each batch undergoes rigorous analytical testing, including Gas Chromatography (GC), to ensure high purity and consistency. Certificates of Analysis (COA) detailing specific batch results are available upon request. We ensure compliance with relevant global regulatory frameworks, including REACH.

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, sparks, and open flame. Containers should be kept tightly sealed when not in use to prevent moisture absorption and maintain product integrity.

Specification

Item	Specification
Appearance	Colorless clear liquid
Identification (IR)	Conforms to standard
Assay (GC)	≥ 98.0%
Refractive Index (n20/D)	1.395 - 1.398
Density (20°C)	0.95 - 0.97 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.