Outline
Overview of Nonionic Emulsifiers for Cosmetics
Features of Nonionic Emulsifiers
Polyethylene Glycols (PEGs)
Silicone Oils
Glyceryl Fatty Acid Esters
Polyglycerol Fatty Acid Esters
Sorbitan Derivatives
Sugar Derivatives
Overview of Nonionic Emulsifiers for Cosmetics
In cosmetic formulations emulsifiers function as essential components that stabilize mixtures of two liquids that normally cannot mix such as oil and water. The reduction of interfacial tension between two liquid phases enables the creation of stable droplets where one liquid becomes dispersed in the other forming an emulsion. The selection of proper emulsifiers plays a critical role in obtaining optimal product texture, stability, and sensory characteristics.
Nonionic emulsifiers achieve widespread usage in cosmetic industry because their neutral charge provides high chemical stability and minimizes skin irritation. Nonionic emulsifiers possess a chemical structure that includes both surfactant properties and an emulsifying effect through their hydrophilic groups which contain hydroxyl (-OH) or ether bonds (R-O-R’) and their lipophilic groups that consist of high carbon fatty alcohol, fatty acid, high carbon fatty amine, fatty amide, and similar compounds. as lipophilic group.
This guide from Alfa Chemistry organizes nonionic cosmetic emulsifiers based on their chemical structure to assist formulators in their decision-making process.
Features of Nonionic Emulsifiers
High Chemical Stability
Nonionic emulsifiers do not ionize in water and therefore do not form ions, which makes them chemically stable under various pH conditions.
Wide pH Range
Nonionic emulsifiers can be used in a wide pH range and remain stable from acidic to alkaline environments.
Good Emulsifying Properties
Nonionic emulsifiers can effectively reduce the surface tension of liquids and form stable emulsions. They are suitable for various liquid/liquid, solid/liquid and gas/liquid emulsions.
Low Irritation and Biocompatibility
Since they do not contain ionic groups, nonionic emulsifiers are usually less irritating to the human body and the environment and have good biocompatibility.
Good Emulsion Stability
Emulsions formed by nonionic emulsifiers have high stability and can maintain stability for a long time under high temperature and high humidity environments, and are suitable for industries such as food and cosmetics.
High Turbidity Point
The solubility of nonionic emulsifiers decreases with increasing temperature. When the temperature is higher than a certain value, the solution will precipitate turbidity, which is called the turbidity point. Obviously, the higher the turbidity point, the wider the temperature range of nonionic emulsifiers.
Diverse Applications
Nonionic emulsifiers are widely used in the fields of chemical industry, medicine, food, cosmetics, textiles, pesticides and petroleum. They can be used to make bread, cakes, shampoo, conditioner, cosmetics, coatings, adhesives and other products.
Silicone Oils
These emulsifiers share standard emulsifying properties but possess enhanced surface activity and spreadability which enables them to lower water surface tension more effectively than typical emulsifiers and makes them ideal for W/O emulsion preparation due to their superior emulsification properties.
Organic silicone emulsifiers mostly exist as liquids or gels. The molecules contain complex branched structures that resist crystallization and remain stable at reduced temperatures. The unique molecular structure provides excellent flexibility to achieve superior methyl stacking which reduces molecular interaction forces and creates a dense monomolecular film on liquid surfaces resulting in outstanding wettability and lubricity.
Features
Excellent emulsification properties.
Multifunctionality, such as moisturizing, softness, smoothness, glossiness, sun protection, antistatic, etc.
High stability.
Good skin feel.
Wide applicability, suitable for a variety of cosmetic types, including creams, lotions, foundation liquids, conditioners, essence oils, etc.
Good compatibility with other ingredients.