Friday, May 17, 2013

Quick note for a long weekend Friday: Cetyl alcohol is not an emulsifier

Quite a few times in the last week I've seen cetyl alcohol referenced as an emulsifier, something that will bring oil and water together. It is not. It's an oil soluble fatty alcohol that should be treated like you would an oil or anything oil soluble, which is to say you can use it in an anhydrous product - like a lotion bar or whipped butter - but you can't use it in anything water based - like a body wash or toner. You cannot use it to create a lotion - you will need an emulsifier for that purpose - but you can use it as a lovely emollient in a lotion. 

Click here for more about all-in-one emulsifiers. 

An emulsifier or surfactant has to have a hydrophilic (water loving) or polar head and a lipophilic (fat loving) or non-polar tail. One end connects with water, the other with oil, and it brings the two things together. Cetyl alcohol, cetearyl alcohol, behenyl alcohol, stearic acid, beeswax, and other waxes only have lipophilic or oil loving parts. They cannot be used as an emulsifier because they lack the hydrophilic or water loving parts, which means they won't bring water and oil together. 

Cetyl alcohol might not be an emulsifier, but it's a great thickener for our products.  I like to use cetyl alcohol in my lotions to increase the viscosity and increase slip and glide. Stearic acid will increase the viscosity, but it offers a little more drag and thickness than cetyl alcohol. It's inexpensive - I think I pay about $4 a pound for it (about $8 a kilogram) - and it works well to moisturize without oils. I like to use it in my facial moisturizers to offer oil free moisturizing to my acne prone skin, and it's a lovely addition to a lotion bar to make it glide a little better. 

If cetearyl alcohol interests you, take a look at this recipe for turning an oil into a whipped butter


canfieldfive said...

Awesome post! I was just wondering if I could add something like this to my lotion as a thickener. I already love it in my conditioner, but I never thought of adding it to lotion! any thoughts on min-max usage rates?

Thanks again! :-)

abigail wickham said...

I rely on this information when i am formulating. I learn the hard way. Mixed a batch of lotion and it was separating. Oh the mistakes...I was trying to not have a waxy feeling but alas had to resort to Emul wax. I prefer Pola wax. It feels so good

Justin Kane said...

I just want to say thank you! As an aspiring cosmetic bodywork DIY'er, I'm IN LOVE with every single post and can't wait to read them all! I've learned more in the past couple of posts than a I have in the past year with trial and error ;P

Thank you thank you thank you!!!

Susan Barclay-Nichols said...

Hi canfieldfive! Yes, you can. Check out this post for more information on cetyl alcohol.