Application Note
Unique hydrophilic rheology modifiers to play with textures
New crosslinked acrylic polymers are particularly interesting compounds for innovative textures thanks to their multifunctionality. Sensient Cosmetic Technologies has developed two specific grades that combine sensoriality and rheology: Covacryl® MV40 & Covacryl® MV60 are bifunctional polymers, falling between thickeners and powders. In the form of particles of controlled sizes (9μm and 13μm respectively), Covacryl®MV40 & Covacryl® MV60 are composed of sodium polyacrylate monomer. This polymer is highly crosslinked to allow the particles to keep their shape, which prevents them from uncoiling when dispersed in water, unlike the common rheological agents. Particles swell in aqueous media without forming a three-dimensional network, thanks to hydrogen bonds and osmotic pressure, and thus provide viscosity to the product. Their high degree of crosslinking also greatly reduces the electrostatic repulsion. Therefore, the polymer is more resistant to pH and electrolytes than non-crosslinked or slightly crosslinked polymers. On the skin, the gels of Covacryl® MV do not form a film. The particles swollen with water behave independently, allowing a slippery application similar to silicone elastomers, and a powdery velvet finish.
The Covacryl® MV40 and Covacryl® MV60 are sodium polyacrylates that allow formulators to offer a multitude of cosmetic products with innovative textures and special touches. They can be used both in skin care or make-up applications (from 0.1 to 5% in quantity in formula). Easy to use, they permit formulators to obtain different kind of textures: frosted gels, light textures, silicone-like and gourmet textures.