I used to have fights with Sodium carbomer all the time on my quest to make a good gel. It is simultaneously one of the hardest and one the easiest ingredients to use.
Sodium carbomer is pre-neutralized carbomer (a polymer) which is used to thicken your mixes… so long as those mixes are not below a pH of 5.5 or 6.
Unlike regular carbomer, this one doesn’t required the usage of triethanolamine (TEA). It also takes a very, very small amount in your formulations to actually create a gel.
I say “gel” in the sense that it turns your water-based solution into a gel, but it really won’t feel like a store-bought gel without all the other things that make the store-bought gel a good hair gel. It just does the heavily lifting of creating the viscosity.
Sodium carbomer is hard to use because, if you’re used to using botanical extracts, just be prepared to test, test, test if you plan to use sodium carbomer with it. It is UBER sensitive to pH.
For example, I created a gel from sodium carbomer and tried to put Marshmallow root extract (regular tea) in it to help with strength. It turned it back into a liquid. Astringent or low pH herbs (teas) DO NOT play well with sodium carbomer.
I’ve confirmed that these ingredients,when used as herbal infusions, cause sodium carbomer not to gel-up:
Slippery Elm Bark
In addition, using a preservative like Neodefend will also turn your gel into a liquid or cause it not to gel up at all (if you add the Neodefend powder to the water before adding the sodium carbomer powder).
When using this, just be prepared not to try to get the pH to 4 or 4.5 to close us your cuticles. Just don’t go there. lol! Save the cuticle closing for your leave-in conditioners.
On the other hand, sodium carbomer is one of the easiest ingredients I’ve ever used because you literally just shake it over your water and stir it like a couple of times every 5-10 minutes.
The recommended usage rate is 0.2% – 0.5%
Just let it sit there and it WILL do the rest. At first it’ll look like fisheyes and you may think you have to whip it. NO! NO! NO!! Leave it alone. I actually had to learn how to leave it alone.
Shake the powder into the water, let it sit for 5 to 10 minutes. Stir slowly with a spoon, spatula or whatever. Then let it sit some more. It will dissolve and thicken.
According to lotioncrafter.com, you can even add sodium carbomer directly into your finished cream (emulsion) to help it thicken up or to add a little hold to it. If you want a gel-consistency just make sure your emulsion/cream has a pH of 5 or above. Make it pH 6 just to make sure.