Description and features

Silqon HMDS (Hexamethyldisilazane) is a strong and versatile liquid silylation agent which has C6H19NSI2 as chemical formula. Unlike chlorosilanes no base is needed as a hydrochloric acceptor.

SilQon HMDS (Hexamethyldisilazane) is also known as Bis(trimethylsilyl)amine, 1,1,1-Trimethyl-N-(trimethylsilyl)silanamine or HDMZ.


Europe: SilQon HMDS is ➔ on stock in our local warehouse. Our lead time is about one week if delivered in 150 Kg drums.

United States, Canada, South America, South Africa and other markets can also be served, please contact our sales department for more details.

This product (CAS: 999-97-3) has been registered under REACH (EC) 1907/2006.

Product Identification

CAS number 999-97-3
EC number 213-668-5
HS code 2931 90 00
EC name 1,1,1,3,3,3-hexamethyldisilazane
IUPAC name bis(trimethylsilyl)amine


AppearanceClear liquid with ammonia odour
Assay≥99.0 %
Hexamethyldisiloxane≤1.0 %


Hydrophobation of substrates for better dispersion and viscosity reduction and for better adhesion as filler in polymers. Also used in production silicone rubber and pharmaceuticals.


Available packaging: 150 KG drums.
Special packaging is available on request.


Store Hexamethyldisilazane cool in a dry and well-ventilated area and in line with legal requirements.
Keep SilQon HMDS away from heat sources and oxidizing agents.


A Material Safety Data Sheets (MSDS) is available for SilQon HMDS and all other products supplied by Vesta Chemicals BV.

An MSDS describes the hazards of a product and explains how a product can be safely handled, used and stored. Besides it provides important regulatory and emergency response information for the purchased product.

Molecular and structural information

Molecular formula C6H19NSI2
Molecular weight 161.39 g/mol
Smiles notation C[Si](C)(C)N[Si](C)(C)C
Structural formula 999-97-3

Physicochemical information

Boiling point 125 ºC @ 1013 hPa
Density 0.77 g/cm3 @ 20°C
Flash point 11.4 °C @ 1013 hPa
Melting point -76.2 °C at 1013 hPa
Log Kow1.19 at 20°C
Solubility in water Not relevant
Vapor pressure (MGM) 2400 Pa at 25°C