CYCLOPENTASILOXANE
GHS08
- H227 Combustible liquid
- H373 May causes damage to organs through prolonged or repeated exposure
- H413 May cause long lasting harmful effects to aquatic life
- P210 Keep away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking.
- P260 Do not breathe dust, fume, gas, mist, vapours or spray.
- P273 Avoid release to the environment.
- P280 Wear protective gloves, protective clothing, eye protection and face protection.
- P319 Get medical help if you feel unwell.
- P370+P378 In case of fire — Use appropriate media to extinguish.
- P403 Store in a well-ventilated place.
Cyclopentasiloxane (D5) is a volatile cyclic silicone carrier prized for fast, non-greasy spreading and clean evaporation. It is selected by grade purpose: a low-residual cosmetic grade for antiperspirants, foundations and hair care; a technical grade for cleaning and coatings; and a D5-carried dimethiconol gum blend for serum feel. RawSource supplies the grade matched to your application and target-market compliance, sourced to spec.
Grade selection — Grade purpose
Cyclopentasiloxane (D5) is a volatile cyclic silicone carrier with a viscosity near 4 cSt, specific gravity ~0.956 and a boiling point near 210 C (PubChem / standard D5 properties). Because it is essentially one molecule, the selection axis is grade purpose and residual/blend, not viscosity — a low-residual cosmetic grade, a technical carrier grade, or a D5-carried gum blend for serum feel.
| Grade purpose | Viscosity | Grade / compliance | Typical applications | Supply |
|---|---|---|---|---|
| Cosmetic / personal-care grade | ~4 cSt | INCI cosmetic (low D4 residual) | volatile carrier for antiperspirant, foundations, primers and hair care (fast-spreading, dry feel) | sourced-to-spec |
| Technical / industrial grade | ~4 cSt | technical | carrier and cleaning solvent for coatings, electronics and process use | sourced-to-spec |
| D5 / dimethiconol blend (gum-in-carrier) | — | cosmetic | serum and hair-care base — high-MW silicone gum delivered in a volatile carrier for slip then dry-down (viscosity varies with gum loading) | sourced-to-spec |
Frequently Asked Questions
What is cyclopentasiloxane (D5)?
Cyclopentasiloxane, or D5, is a volatile cyclic silicone (decamethylcyclopentasiloxane, CAS 541-02-6) used as a fast-spreading, non-greasy carrier. Its viscosity is about 4 cSt and it evaporates cleanly, which is why it carries actives in antiperspirants, color cosmetics and hair care.
Is cyclopentasiloxane restricted?
Yes, in some markets. Under EU REACH Annex XVII (entry 70), D4, D5 and D6 are restricted in many wash-off and leave-on cosmetic products. Confirm the compliance grade for your target market when specifying; a grade-specific CoA and SDS ship with every order.
What CAS number is cyclopentasiloxane?
D5 is CAS 541-02-6 (decamethylcyclopentasiloxane), molecular formula C10H30O5Si5, molar mass 370.77. Because it is a defined cyclic molecule, its physical properties are fixed; grades differ by purpose, residual content and whether it is supplied neat or as a gum blend.
Identity and hazard data sourced from PubChem and authoritative regulatory references. Confirm against the grade-specific CoA and SDS supplied with every shipment.