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.
Request SDS →Silicone Oil 5000 cSt is a viscous linear PDMS (dimethicone) fluid and one of the classic mechanical damping grades. Sitting between the 1000 cSt and 10000 cSt fluids, it is thick and slow-flowing yet still a pourable liquid, giving the controlled, temperature-stable resistance that dashpots, dampers and instrument mechanisms rely on. It retains the PDMS family’s wide service-temperature range, low viscosity-to-temperature coefficient, dielectric strength and chemical inertness.
Typical Properties
The values below describe the nominal 5000 cSt grade. They are typical values, not a specification; the Certificate of Analysis (CoA) for the lot you purchase governs.
| Property | Typical Value |
|---|---|
| INCI Name | Dimethicone |
| CAS Number | 9006-65-9 |
| Appearance | Clear, colorless liquid |
| Viscosity (25 °C) | ~5000 cSt |
| Specific gravity (25 °C) | ~0.973 |
| Refractive index (25 °C) | ~1.404 |
| Solubility | Insoluble in water; soluble in many organic solvents |
| Flammability / handling | Refer to the current SDS |
Applications
In mechanical and vibration damping — its signature use — 5000 cSt is a standard fluid for dashpots, rotary and linear dampers, soft-close hinges, dials and knobs, meter and instrument needle damping, and anywhere smooth, repeatable, temperature-stable resistance is needed; the low viscosity-temperature coefficient keeps the damping consistent across a wide range. In heavy lubrication and slip, the thick film carries high loads and gives long-lasting slip and difficult mold release in rubber and plastics processing, as an internal or external lubricant. In polishes and protectants, it builds the most durable gloss and water-beading film of the common pourable grades. It also serves as a dielectric and insulating fluid, an antifoam / defoamer concentrate base, and — at low percentages — a very substantive conditioning and gloss additive in personal-care formulation (a formulation-feel role, not a skin-health claim).
Where 5000 cSt sits on the ladder
Below 5000 cSt are 1000, 500 and 350 cSt, which pour and spread more readily and are oriented to lubrication and feel; above it are 10000 cSt and the very high grades (12500, 60000, 100000, 500000 cSt), which are heavier still and shade into gums. 5000 cSt is the entry point to true damping duty — thick enough to damp, still fluid enough to dispense. The silicone oil viscosity guide walks the full ladder grade by grade.
Grades & bulk sourcing
RawSource supplies Silicone Oil 5000 cSt in drums, totes and IBCs, with bulk quantities held in domestic US stock for short lead times. Every lot ships with a CoA, and the SDS is available on request. Confirm the grade for your application before you commit a production run — match viscosity to the spreading, persistence and film weight your formulation needs.
Related products
Compare neighboring grades and identifiers: Silicone Oil 1000 cSt, Silicone Oil 10000 cSt, Silicone Oil 500 cSt, Silicone Oil 350 cSt, and the parent Dimethicone (PDMS fluid). See the full range on the bulk silicone oil supplier hub.
Frequently Asked Questions
What does cSt mean in silicone oil?
cSt is centistokes, the unit of kinematic viscosity. For silicone oil (PDMS, CAS 9006-65-9) it indicates how thin or thick the fluid is; 5000 cSt is a viscous, slow-flowing grade.
What is silicone oil 5000 cSt used for?
It is best known as a mechanical damping fluid (dashpots, dampers, soft-close hinges, instrument damping), and is also used for heavy lubrication and difficult mold release, durable polish gloss, dielectric and insulating duty, and as an antifoam concentrate base. Match the grade to your application.
How does silicone oil 5000 cSt differ from the 1000 and 10000 cSt grades?
All three share CAS 9006-65-9 and differ only in chain length and viscosity. 5000 cSt lays down a more substantive, more persistent film than 1000 cSt and spreads more readily than 10000 cSt. Step down to 1000 cSt for faster spread and a lighter film; step up to 10000 cSt for a heavier, longer-lasting film.
What is the CAS number for silicone oil 5000 cSt?
Silicone oil (dimethicone, PDMS) carries CAS 9006-65-9 with the repeating-unit formula (C2H6OSi)n. The 5000 cSt label is the viscosity grade, not a separate CAS; all dimethicone viscosity grades share this number.
Can silicone oil 5000 cSt be supplied in bulk?
Yes. RawSource supplies 5000 cSt silicone oil in drum, tote, and IBC quantities from domestic US stock. Request a bulk quote with your target volume and packaging; CoA and SDS are available on request.
Disclaimer. Information on this page — including chemical properties, identifiers, hazard, transport (DOT/UN) and tariff (HS) classifications, and applications — is provided for general reference and is compiled from authoritative public sources. Values are typical and are not a guaranteed specification; the Certificate of Analysis (CoA) for the lot you purchase governs. Products are sold for industrial and professional use only. Nothing here is a medical, health, or efficacy claim, or advice. Always consult the current Safety Data Sheet (SDS) before handling, storage, transport or disposal, and confirm regulatory status, classification and suitability for your application and jurisdiction. Hazard, transport and tariff classifications must be verified for your specific shipment. RawSource makes no warranty, express or implied, and assumes no liability for use of this information.