Thickeners: Cationic guar gum

I finally got around to buying some cationic guar or guar hydroxypropyltrimonium chloride (sometimes listed as GuarSilk) a few weeks ago from Creations from Eden (also available at the Herbarie) and I thought I'd try it out in a few surfactant based products to see how it compares to my other cationic polymers (like polyquat 7, polyquat 10, polyquat 44, and honeyquat). So what is cationic guar gum?

Guar gum is "a galactomannose polysaccharide derived from the endosperm of Cyamopsis tetragonolobos seeds" (aka guar beans). The guar gum is then depolymerized and its molecular weight is modified to increase solubility and thickening properties. Cationic guar derivatives are created by reacting hydroxypropyl with epoxypropyltrimethyl ammonium chloride to create a positive charge. (Polyquat 10 and 24 are derived from cellulose - the numbers on the polyquats indicate what the starting ingredient was, not how many molecules or other thingies are on it.)

So cationic guar gum is guar gum that has been modified to have a positive charge, which means it will be substantive to our hair and skin, so we use it as a conditioning agent in our products.

So how do we use it? Cationic guar gum comes as a light yellow powder, and we use it at 0.2% to 1% in our products. It's soluble in water, dispersible in glycerin and glycols, and insoluble in oils. It works best in a solution with a pH of 7 or lower (its actual pH is around 9) because that's when it'll have a positive charge (it's not substantive without the positive charge, so this is very important) and when it thickens best. It can create gels, although they might be hazy, and they work well with our surfactants, so we can make conditioning shampoos, body washes, and any other cleansing product where you want a little thickening and conditioning.

There's one down side to using cationic guar gum - it's not as easily removed from our hair by our surfactants as some of our other cationic polymers, which means it can lead to build up on our hair.

The suggestions I've seen for using it are as follows - add to room temperature distilled water and mix well, stirring occasionally for about 15 minutes (although it could take as long as 30 minutes). When the cationic guar gum is hydrated, add to the heated water phase of your product and stir well.

Cationic guar gum is film forming, imparts a smooth and silky feel to skin, acts as an anti-irritant and mildness increaser in surfactant systems, and can increase your foam feel and quality. And it's a conditioning agent that is substantive, but I've already mentioned that quite a few times!

Please note: Normal guar gum does work as a thickener, but it is not positively charged, so it won't act as a conditioning agent and isn't substantive. You need to use the cationic guar gum to call something a conditioner. 

Join me tomorrow for a little more on thickeners - guar gum!