Dimethicone Copolyol is an inorganic chemical compound, a polymer consisting of dirnetilsiloxane with polyoxyethylene and/or polyoxypropylene side chains. Soluble in water if it has at least 40 per cent polyoxyethylene groups.

Safety
Dimethicone is a chemical compound, derived from silicone, a mixture of linear methylated siloxane polymers, a chemically inert silicone-based polymer. It is considered safe when formulated to be non-irritating in cosmetic products.
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What it is used for and where
Cosmetics
Emulsifying agent. Emulsions are thermodynamically unstable. Emulsifiers have the property to reduce the oil/water or water/oil interfacial tension, improve emulsion stability and also directly influence the stability, sensory properties and surface tension of sunscreens by modulating their filmometric performance.
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