Hydrogenated Castor Oil/Sebacic Acid Copolymer

Hydrogenated castor oil/sebacic acid copolymer is a synthetic polymer created by chemically linking hydrogenated castor oil with sebacic acid. This combination produces a conditioning agent that sits somewhere between a traditional oil and a waxy polymer, giving it a smooth texture without the heaviness of natural oils.In skincare products, it functions primarily as an emollient and skin conditioner, helping to soften and smooth the skin's surface. It's also used in haircare formulations for similar conditioning benefits.

As a synthetic copolymer, this ingredient works by coating the skin's surface with a thin, protective film. This film reduces transepidermal water loss (the natural evaporation of moisture from the skin) while remaining lightweight enough not to feel occlusive or heavy.The polymer structure also allows the ingredient to spread evenly across the skin and hair, creating a smooth, conditioned appearance without clumping or building up unevenly.

This ingredient is typically encountered in finished formulations rather than used as a standalone addition. When present in a moisturiser or serum, apply it as directed in the product instructions—usually once or twice daily. It blends well in emulsions and can be layered with other skincare steps without issue. There's no minimum waiting time required before application of subsequent products.

Generally considered safe and well-tolerated across skin types. Some users with fungal acne sensitivities have reported that products containing certain synthetic polymers may exacerbate their condition, though evidence is anecdotal; if you have fungal acne, patch test before full application.