Crosslinked polymers of polydimethylsiloxane and vinyl polydimethylsiloxane are classic silicone elastomer substrates in the cosmetics industry. They rely on the crosslinking of siloxane chains to build a three-dimensional network structure, forming the basic framework of the second composite material. Both have identical core components; the difference lies in the additional addition of silica (silica) to the latter. The INCI name uses "(and)" to indicate the added components, classifying them as homologous derivatives of composite materials.
Pure crosslinked polymers commonly exist as silicone gels, typically dispersed in silicone oil carriers. They possess basic abilities such as soft-focusing, oil absorption, and improved skin feel. They can thicken the oil phase, resulting in a silky matte finish after application. They are often used to optimize the application experience of skincare and foundation products, reducing greasiness and minimizing pores and fine lines.
Silica itself is a porous inorganic powder with outstanding oil absorption capabilities. Combining silica with silicone elastomers yields an elastomer composite powder. Silica adheres to the surface of the elastomer particles, altering the material's physical morphology from a gel to a loose powder, while simultaneously enhancing its oil absorption and dispersing properties.
Both materials exhibit good formulation compatibility, are non-comedogenic, and are suitable for oil-phase systems. In short, the pure cross-linked polymer serves as the base, and the addition of silica modifies it to create the composite powder. Formulators can choose between the two based on skin feel and dosage form requirements.