Polymethylsilsesquioxane

Polymethylsilsesquioxane (CAS 68554-70-1) is a spherical silicone resin powder used to modify surface texture. Also marketed as MSP-S and known as Me silsesquioxane.

Where is Polymethylsilsesquioxane used?

• Color cosmetics and skincare: soft-focus agent and skin-feel modifier that reduces shine, blurs imperfections and improves spreadability in foundations, primers and pressed powders
• Coatings: matting agent and anti-blocking additive in UV-cure, solvent-borne and waterborne systems
• Adhesives and sealants: rheology adjuster that reduces surface tack
• Plastics: processing aid and surface modifier for scratch resistance
• It lowers the coefficient of friction in films and molded parts.

Good to know: Its crosslinked three-dimensional structure delivers performance conventional silicone fluids or standard fillers cannot replicate. Purity and particle size specifications vary by manufacturer and should be confirmed against application requirements.

Commercial specifications

• Particle size distributions typically range from submicron to several microns