DISILOXANE- ▸ Silicone intermediate: chain stopper capping chain length in polydimethylsiloxane (PDMS) manufacture
- ▸ Volatile carrier: fast-evaporating spreading agent for antiperspirants, lotions and hair care
- ▸ Process solvent: low-residue cleaning solvent for electronics and coatings
- ▸ Mold release: carrier and release fluid for industrial molding
Don’t see your viscosity? We can custom-formulate silicone fluid to your target cSt — tell us your spec.
Not sure which grade? Silicone oil viscosity guide (5 to 500,000 cSt) · All silicone oils
A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.
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Transport classification per the UN Model Regulations / 49 CFR 172.101 Hazardous Materials Table. Confirm against the grade-specific SDS (Section 14) before shipping.
Hexamethyldisiloxane (MM / HMDSO, CAS 107-46-0) is the shortest linear siloxane and the most volatile silicone fluid, at roughly 0.65 cSt. Sold in the trade as MM fluid, it serves as a chain stopper that caps chain length in polydimethylsiloxane (PDMS) manufacture, as a fast-evaporating carrier and spreading agent in personal care, and as a low-residue solvent in industrial and laboratory use. It is the volatile bottom of the silicone viscosity ladder; the next grades up are MDM (1 cSt) and MD2M (1.5 cSt). RawSource supplies MM fluid in bulk, sourced to spec, with CoA and SDS on every order.
Regulatory & registration requirements
- TSCA (US):
- REACH (EU):
- EC number: 203-492-7
Source: EPA TSCA Inventory (July 2025 release) · ECHA CHEM — retrieved 2026-07-12
Frequently Asked Questions
What is hexamethyldisiloxane used for?
Hexamethyldisiloxane (HMDSO/MM, CAS 107-46-0) is a low-viscosity, volatile silicone fluid used as a carrier solvent and viscosity reducer in silicone and personal-care formulations and as a building-block intermediate in the synthesis of silicone polymers. RawSource supplies it in bulk to silicone and formulation manufacturers.
Is hexamethyldisiloxane a silicone?
Yes. Hexamethyldisiloxane is the simplest siloxane, with a silicon-oxygen-silicon backbone and six methyl groups (C6H18OSi2). It is the basic structural unit underlying larger silicone fluids and polymers.
Is hexamethyldisiloxane water soluble?
No, hexamethyldisiloxane is a hydrophobic siloxane and is essentially insoluble in water; it is miscible with organic solvents and functions as a volatile carrier in non-aqueous systems. See the SDS and technical data sheet for solvency and volatility data.
How is hexamethyldisiloxane shipped, given its UN number?
Hexamethyldisiloxane is a flammable liquid assigned UN 1993, so it ships under DOT/IATA/IMDG hazardous-materials rules with appropriate packaging and labeling. RawSource supplies the SDS with each order; confirm packaging and mode requirements with your carrier.
How is bulk hexamethyldisiloxane packaged and quoted?
RawSource ships HMDSO as a bulk liquid in DOT-compliant drums and totes for silicone and personal-care accounts. Pricing depends on volume, packaging, and hazmat freight; submit an RFQ with your quantity and ship-to for a current quote with CoA and SDS.
What is the REACH and TSCA regulatory status of Hexamethyldisiloxane (MM, HMDSO)?
Hexamethyldisiloxane (MM, HMDSO) (CAS 107-46-0) is subject to U.S. TSCA Inventory requirements; supplying it into the EU requires valid REACH registration ((EC) No 1907/2006). RawSource cannot verify a third-party supplier's registrations — buyers should require documented TSCA and REACH compliance for their jurisdiction and volume (EC 203-492-7).