Emulsifying Wax: What is it and how does it work?
Emulsifying wax is one of the essential ingredients in making lotions and creams. Think of it as the “glue” that will hold your recipe together. We’ve all seen how oily salad dressings separate after sitting for a while. You then shake the bottle until it appears to be mixed, but if you look at it closely, you will see little balls of the oil suspended in the liquid. Left to sit, the dressing will again separate into its different properties.
Lotions and creams are created from a mixture of water and oils. Without the addition of emulsifying wax, they too would separate back into water and oils.
Adding emulsifying wax to your recipe will keep the oil and water from separating by creating an emulsion between the oil and water. An emulsion is a system consisting of a liquid dispersed in an immiscible liquid. Immiscible means not compatible: not able to mix together to make a solution. Oil and water are a great example of two immiscible liquids. Emulsifying wax will also thicken your creation. If it were not included in your recipe, you would end up with a mixture that is similar to the consistency of salad dressing! Everyone knows that oil and water don’t mix, so how does the wax accomplish this seemingly impossible task?
Emulsifiers actually work on a molecular level, by attracting both water and oil to different sites at the same time. Water is a polar material. Things that like water are also called polar materials. Polar materials are also called hydrophilic. Hydrophilic materials are water-loving materials. Non-polar materials like olive oil are hydrophobic. Hydrophobic means water hating. An emulsifier has a hydrophilic portion and a hydrophobic portion. This essentially means that it can effective bind both water and oils. It means that some structures of the emulsifier attract oil, while others soak up water like a sponge. Each part traps the liquid keeping it from breaking free to separate. As an added bonus, because the oil remains mixed with the water, the wax actually helps the oil penetrate the skin, thereby replacing lost moisture.
No, you don’t have to be a chemist to enjoy making your own lotions and creams! But you now know why emulsifying waxes are so important to your end product and how they work. Not only is the information useful in making soaps and lotions, but also your friends will be impressed with how smart you are!
Choosing an emulsifier can be rather confusing, but learning a bit about those that are available will help you make a decision. The most common emulsifiers used by hobbyists include: Emulsifying Wax NF, Cetearyl Alcohol/Ceteareth 20, Cetearyl Alcohol, Glyceryl Stearate, Polysorbate 20, Ceteareth 20. Let's see what the differences are:
Emulsifying Wax NF: Use this waxy material to emulsify your water and oils together. Usage varies based on the combination of thickeners but normal usage rates are between 3 and 6% of the total weight of your recipe. This is one of the easiest emulsifiers to use and is used by most home crafters of lotions and creams.
Cetearyl Alcohol/Ceteareth 20 - Used as an emulsifying wax in lotions, this is a waxy pastille that is used in concentrations of 2 and 6% of the lotion recipe and can be used in combination with emulsifying wax. This product creates a thicker, waxier end product, and is excellent for foot and elbow creams which traditionally require a thicker, waxier cream.
Cetearyl Alcohol - Fatty alcohol derived from natural oils and fats (cetyl and stearyl alcohol) that can be used to thicken and stabilize formulations. Cetearyl Alcohol imparts an emollient feel to the skin. Recommended usage level: 1-25%.
Glyceryl Stearate - Emulsifier and emulsion stabilizer. Typically used with another emulsifier, such as polysorbate 20 or ceteareth 20. Typical Usage Rate: .1-3%
Polysorbate 20 - Excellent oil in water emulsifier/solubilizer. For use in body mist, room spray, skin cleansers. Recommended use is 1/1 or 1/2 ratio of fragrance oil or essential oil to polysorbate 20.
Ceteareth 20 - Used in oil-in-water emulsions. Provides exceptionally stable emulsions when used in combination with another emulsifier such as glyceryl stearate.
The waxes listed here do not reflect a complete list of the emulsifiers that are available, but they are some of the more popular ones used by the soap and lotion enthusiast. There are many recipes for making lotions and soaps, which will most likely indicate the type of emulsifier used and how much should be added to attain the desired effect. Knowing more about emulsifiers are used will help to take the mystery out of how and why they are used. You may even want to experiment with your own concoction to create a product that is uniquely yours.