Thursday, August 9, 2012

Emulsifiers: What's a complete or all-in-one emulsifier?

I found a comment from someone who was having trouble with lotion separation. In the message, she notes that she is using the base emulsifier from Aromantic in the UK. This is not a complete emulsifier - it's glyceryl monostearate, a low HLB emulsifier that must be coupled with a high HLB emulsifier to create a complete emulsifier. The supplier recommends that you combine it with cetyl alcohol to create a complete emulsifier, but cetyl alcohol is not a high HLB emulsifier - it's a fatty alcohol, which means it's part of the oil phase. (Click here to learn more about the HLB system we can use to make our own emulsifiers). You won't be able to make a proper, stable emulsifier using glyceryl monostearate and cetyl alcohol.

You might be able to make an emulsification by sheer force (mechanical emulsification) or by heating and holding it (heat emulsification), but these are both unstable forms of emulsification. When we use proper emulsifiers, we create a chemical emulsification, which is the most stable version of all. Think of salad dressing - we create a mechanical emulsification by shaking the bottle. I know there are some of you who will swear by this product and have had great success, but what you've made isn't a chemical emulsion and it's not stable. We can't argue with the laws of chemistry! 

If you want to use something like this glyceryl monostearate (HLB value 3.8), you'll have to combine it with a high HLB emulsifier like ceteareth-20 (HLB value 15.2) or polysorbate 80 (HLB value 15) to create a lovely emulsifier. (Click on the links below to learn how to do this!)

Related posts:
HLB system: The start of the series
HLB system: A demonstration (part 1)
HLB system: A demonstration (part 2)

What does it mean to have a complete or all-in-one emulsifier? It means that the emulsifier does not require anything else to emulsify your product. Something like Polawax, Incroquat BTMS-50, Sucragel AOF, Ritamulse SCG, or emulsifying wax would be considered complete emulsification systems. You can use these at the suggested usage rates in your products without having to add anything else for awesome emulsions.

Check the INCI name of the product you're thinking of purchasing. If you see something that says emulsifying wax NF, then you're getting emulsifying wax NF. If you see something that only has one ingredient - let's say something like glyceryl monstearate or ceteareth-20 or polysorbate 80 - you aren't getting a complete emulsifier. You're getting something that has to be combined with something else to create an emulsion. There's nothing wrong with these ingredients, except they won't create a lotion for you.

Related posts:
Emulsifiers - check to see what you're getting! 
INCI names (part one)
INCI names (part two)


Organa said...

Hi Susan, I wonder if has worked with the base of Croda (Crodabase CR2),
I bought some of that base, but not yet used it, just add water would be enough or do you think would be important to some additive?
As to your last post, I seem to be incompatible with polaxamer Parabens, a preservative but I see there obviously the product of Vick (Iodopropynyl Butylcarbamate).
Learning a lot from you, thanks.

Jane Barber said...
This comment has been removed by the author.
Poyntee said...

It is a good idea to ask the manufacturer or look in the scientific literature as to what the HLB values of different things are.
I remember from a while back that the HLB of 5 was being circulated around on the SoapDishArchives community for Caprylic Triglycerides. It probably isn't 5, as all of my HLB emulsification systems treating the caprylic as 5 failed.
Treating the Caprylic Triglycerides as though it had an HLB of ~11 seems to be working for me - I have an extremely stable emulsion that is still holding together after mold has settled in on it!

Acuchica said...

Susan, I am a newbie and am taking a crash course on HLB's using the in depth information you've provided on this site. I have a question about the complete emulsifier Xyliance from The Herbarie. It says it's composed of Cetearyl Wheat Straw Glycosides (and) Cetearyl Alcohol and has an HLB of 10.5
I know that Cetearyl Alcohol has an HLB of 15.5. But can find no HLB on the Cetearyl Wheat Straw Glycosides anywhere. I'm figuring that HLB would have to be low, but am confused because it is listed as first ingredient. Am I wrong in assuming that being listed first means you have more or equal weight in the formulation? Any help would be greatly appreciated. I'm using it and like the feel but several of my lotions separate and I'm going back to try to dissect each formula, thinking it might be the an HLB issue.