Polyglycerol-6 Ricinoleate (Emulsifier)

Polyglycerol-6 Ricinoleate – Non-Ionic Emulsifier and Skin Conditioner for Cosmetics and Pharmaceuticals

Chemical Structure and Synthesis
Polyglycerol-6 ricinoleate is produced by the esterification of polyglycerin-6 (hexaglycerin, a polymer consisting of six glycerol units) with ricinoleic acid, the main fatty acid found in castor oil. Depending on reaction conditions, one or more hydroxyl groups of the polyglycerol backbone are substituted with ricinoleate fragments. The synthesis can be represented as:
Polyglycerin-6 + m Ricinoleic Acid → Polyglycerol-6 Ricinoleate + m H₂O
where m represents the degree of esterification. By controlling reaction conditions, the degree of esterification and thus the physicochemical properties of the product can be tailored to meet specific formulation requirements.

Physicochemical Properties

• Enhanced lipophilicity: The larger molecular weight of the polyglycerol-6 backbone provides improved oil phase distribution and compatibility.

• Emulsifying activity: The longer hydrophilic chain of six glycerol units, combined with lipophilic ricinoleate fragments, effectively reduces interfacial tension, stabilizing both water-in-oil (W/O) and oil-in-water (O/W) emulsions.

• Film-forming properties: Forms protective films that improve the tactile qualities of cosmetic products and enhance product longevity.

• Skin conditioning: The polyglycerol moiety provides humectant properties, enhancing skin hydration and softness.

• Good solubility: Soluble in oils and organic solvents; dispersible in water.

• Non-ionic: Compatible with a wide range of ingredients and pH levels.

• Chemical stability: Ester bonds are resistant to moderate temperatures and aggressive environments, ensuring long shelf life.

• Biodegradable and derived from renewable castor oil sources.

Applications

• Cosmetics and personal care: Used as a primary or co-emulsifier, emollient, and moisturizer in W/O and O/W creams, lotions, serums, sunscreens, makeup removers, lip products, and hair care formulations. Provides stable, elegant textures with good spreadability, enhanced hydration, and a smooth, non-greasy feel.

• Pharmaceuticals: Employed as an emulsifier, solubilizer, and penetration enhancer in topical ointments, creams, and suppositories for uniform delivery of active ingredients.

• Specialty polymers and industrial: Applied as a lubricant, plasticizer, and dispersant in specialty chemical formulations and protective films.

Key Benefits

• Effective emulsification for both W/O and O/W systems.

• Enhanced lipophilicity – improves oil phase compatibility.

• Mild and non-irritating – suitable for sensitive skin.

• Provides moisturizing, skin-softening, and film-forming properties.

• Thermal and oxidative stability – reliable over a wide temperature range.

• Biocompatible, biodegradable, and of natural origin.

• Compatible with a wide range of cosmetic and pharmaceutical ingredients.

• Acts as a co-emulsifier, thickener, and stabilizer in complex formulations.

Recommended Use
Typical usage levels range from 1–5% of the formulation, depending on the desired emulsion stability, viscosity, and moisturizing effect. For optimal performance, dissolve in the oil phase at elevated temperatures (60–70°C) before emulsification. Can be combined with co-emulsifiers and thickeners for tailored rheology.

Safety and Handling

• Generally recognized as safe for use in cosmetics and personal care at recommended concentrations.

• Low irritation potential; well-tolerated by skin.

• Avoid contact with strong oxidizers and acids.

• Store in a cool, dry place, away from direct sunlight.

• Use appropriate personal protective equipment (gloves, safety goggles) when handling.

Quality Assurance
Each batch is tested for acid value, saponification value, and emulsification performance to ensure consistent quality.