POLYMETHYLSILSESQUIOXANE- ▸ Slip modifier: Spherical particles add silky, dry slip.
- ▸ Soft-focus/mattifying: Diffuses light and reduces shine.
- ▸ Bulking agent: Adds powder volume and texture.
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 →Polymethylsilsesquioxane (CAS 68554-70-1) is a crosslinked methylsilsesquioxane silicone resin, typically supplied as fine spherical powder. It is used as a bulking agent and slip modifier that imparts a smooth, dry, soft-focus feel in color cosmetics and skin-care formulations.
Regulatory & registration requirements
- TSCA (US):
- REACH (EU): Not determined from public registry
- EC number: 614-610-5
TSCA Inventory flag XU: a substance exempt from reporting under the Chemical Data Reporting Rule (40 CFR 711) (EPA flag legend).
TSCA Inventory flag PMN: a commenced PMN (premanufacture notice) substance (EPA flag legend).
Source: EPA TSCA Inventory (July 2025 release) · ECHA CHEM — retrieved 2026-07-12
Solutions Using This Product
Process-solution guides on this site that specify this chemistry:
- Anti-Graffiti & Easy-Clean Coating Chemistry (Coatings & Construction)
Frequently Asked Questions
What is polymethylsilsesquioxane used for?
Polymethylsilsesquioxane (CAS 68554-70-1) is a crosslinked silicone resin, typically fine spherical powder, used as a slip modifier, soft-focus/mattifying agent, and bulking agent in color cosmetics and skin-care formulations.
Is polymethylsilsesquioxane a silicone?
Yes. It is a crosslinked methylsilsesquioxane silicone resin (CAS 68554-70-1) supplied as spherical powder, distinct from fluid silicones like polydimethylsiloxane.
How does polymethylsilsesquioxane differ from polydimethylsiloxane?
Polydimethylsiloxane is a linear silicone fluid, while polymethylsilsesquioxane is a crosslinked resin in spherical powder form. The spherical particles deliver dry slip and light-diffusing soft-focus that a fluid cannot.
What is the HS code for polymethylsilsesquioxane?
It classifies under HS 3910.00 (silicones in primary forms). Confirm the final classification with your customs broker for the specific powder grade.
What is the cost of bulk polymethylsilsesquioxane?
Pricing depends on particle-size grade and order volume. Request a current quote from RawSource specifying grade and volume; a CoA and SDS accompany each shipment.
What is the REACH and TSCA regulatory status of Polymethylsilsesquioxane?
Polymethylsilsesquioxane (CAS 68554-70-1) is listed as Active on the U.S. EPA TSCA Inventory; its REACH registration status is not determined from the public ECHA registry.