What it is
This ingredient is a silicone copolymer composed of a polydimethylsiloxane (dimethicone) backbone grafted with methyl(undecyl glyceryl ether) side chains. The undecyl (11-carbon) glyceryl ether pendant groups introduce hydrophilic character, making the polymer amphiphilic compared to plain dimethicone. In formulations it spreads readily due to the low surface tension typical of silicones, leaving a thin, flexible, vapor-permeable film on skin and hair. The glyceryl ether modification improves compatibility with aqueous phases and may assist in water-in-oil emulsion stabilization. It is non-comedogenic and generally well-tolerated. Used primarily in foundations, concealers, lip products, and skin care preparations where a smooth, non-greasy finish is desired.
Safety & warnings
As a high-molecular-weight polymer, the ingredient is not expected to penetrate intact skin. Silicones of this class are generally considered non-irritating and non-sensitizing. No widespread reports of allergic contact dermatitis specific to this copolymer exist. The glyceryl ether groups make it more water-compatible than plain dimethicone but do not introduce known irritation risks. Individuals with silicone sensitivity should use caution. No comedogenicity concerns have been identified for this polymer class.
Origin & sourcing
Synthetically manufactured by grafting glyceryl ether-terminated undecyl groups onto a methylsiloxane/dimethylsiloxane copolymer backbone via hydrosilylation or related organosilicon chemistry. All starting materials are derived from petrochemical and chlorosilane processing; no natural or botanical source is involved.
History
Glyceryl-modified siloxane polymers were developed as part of efforts to increase the compatibility of silicone polymers with water and polyol-containing cosmetic formulas. Pendant glyceryl ether modifications on dimethicone backbones gained use in luxury color cosmetics from the late 1990s onward, appearing prominently in long-wear foundations from brands such as Dior, Givenchy, and Guerlain. The INCI name is listed in the EU CosIng ingredient database as a film-forming silicone derivative.
Questions everyone asks
What makes this copolymer different from plain dimethicone?
The undecyl glyceryl ether side chains introduce hydrophilic segments into the otherwise water-repellent silicone backbone, improving compatibility with water-based formulas and polyols, while retaining dimethicone's smooth, film-forming sensory profile.
What products typically contain this ingredient?
It is found mainly in long-wear foundations, concealers, and lip products—categories where silky texture, adhesion, and a flexible film are valued. Brands such as Dior and Givenchy have used it in fluid foundation formulas.
Is it safe for sensitive skin?
The ingredient is non-comedogenic and generally well-tolerated. High-molecular-weight silicone polymers are not absorbed through intact skin, reducing systemic exposure concerns. People with documented silicone sensitivities should patch-test.
Is this ingredient natural or synthetic?
It is entirely synthetic, produced through organosilicon chemistry. It has no botanical or animal-derived components.