Friday, August 30, 2013

Gels (revised for 2013)!

I admit I have a thing for gels. It's so cool to see some water and some powder come together to create something so thick a fork can stand up in it! I've written about them in the past, but I thought it would be fun to do a little update on the topic.

What's the deal with gels?
I'm using what's called Carbopol Ultrez 20 gelling agent (INCI: Acrylates/C10-30 Alkyl Acrylate Crosspolymer), which you'll see in the ingredient list of a lot of gelled products, like hair gel or aloe vera gel. I've written about this before, so I'll refer you to that post for more information.

In short, we get this gelling agent wet then add a really alkaline thing - an 18% lye solution or triethanolamine - which turns it into a gel. We can use this gel on its own to make a gelled product, like a hair gel, or use it in a lotion to give a more cushiony feeling.

Take a look at a commercial lotion you like. Odds are pretty good that you'll see a carbomer in there. It offers a moistened, cushiony feeling to that lotion. 

96.8% distilled water
1.2% Carbopol Ultrez 20
1.6% 18% lye solution or triethanolamine
0.4% liquid Germall Plus (or preservative of choice)
Why include a preservative in the gel? Because I made a big batch and wanted to save it. If you are planning to use what you make and not save it, don't worry about preserving it in gel form. You'll be adding preservative to the final product in which you use it in that case. If you do preserve it and add it to something later, don't worry about having too much preservative. Lots of things we use have preservative added to them - specifically, ingredients that contain water like surfactants, proteins, and so on - and we don't run into issues with over-preserving there.

Related post:
Are the preservatives we find in our ingredients enough to preserve a product? (No.)

Weigh the water into a container and sprinkle the carbomer into the water. Stir really lightly to get all the bits wet and let it sit for about 5 minutes.

It is pretty important to use distilled water here as we don't want any salts or metals from tap water in the mix as it can mess up the viscosity.

In the meantime, you can combine 82% distilled water with 18% lye and let it completely react. Definitely use a heat proof container as this is an exothermic reaction that issues a lot of heat and a plastic container might not be able to withstand it. (It's not like it's molten lava hot, but it's up there!) Make sure you're wearing eye protection and gloves when you work with lye!

Please write something like "lye solution" and a skull and crossbones on any container with lye because it looks like water and doesn't really smell like anything other than water. But it can hurt if you spill it on yourself.

An exothermic reaction is one that produces heat. An endothermic reaction requires heat. I always remember is that I have to put heat "endo" an endothermic reaction, and that heat "exos" an exothermic reaction. 

This is what it will look like when it is "wetted". I know, weird word, right? But it's all about getting each and every tiny bit of powder wet before adding the neutralizer.

Put your container back on the scale and add your neutralizer. Mix really well. It should thicken in a few seconds, but it might take up to a minute. Mix ing by hand is sufficient, although you can use some kind of device, if you want.

This version of gel - 1.2% carbomer to 1.6% neutralizer - will create a thick gel. If you want a thinner gel, add less carbomer say 0.9% carbomer to 1.2% neutralizer. You'll have to play around to find that ratio you like.

It works out to about 3:4 ratio of carbomer to neutralizer. If you want a thicker gel, use more of each. Want a thinner gel? Use less of each. 

Gel on its own isn't sticky; it's what we add to it that makes it feel that way. So if we want to make a less sticky feeling aloe vera gel, we'd make up the gel and add some aloe vera to it. (Check your gelling agent to make sure it works well with the ingredients you've chosen. Electrolytes like aloe vera can mess with some gels.) Ultrez 20 works well with electrolytes, so I can use it with things like aloe vera or surfactants.

Related posts about gels:
Gels: Ooey gooey fun!
Gels: Aloe vera
Gels: Surfactant-y fun
Gels: Hair styling gel
Gels: Make a gel based toner

Related posts on gel-like things that don't use carbomer, but instead use Amaze XT or gums:
Amaze XT
Amaze XT: Making detanglers
Surfactants: Building viscosity (scroll down for Amaze XT information)
Facial scrubs: Working on our surfactant base (part 4)
When to add ingredients (part 2)
Experiments in the workshop: Min-maxed toner becomes facial gel
Iron Chemist results: LSB

We'll get to some comments Saturday and Sunday and come back to gels on Monday! It'll give you time to think about what you'd like to make! (I'm working on a liquid eye liner sealant, and I should have some information about what people think by then!)


Kathy said...

Susan - So I made a thick gel, and added the 18% lye solution, but when when I added SMC Taurate, the gel turned to a thinner liquid.... I want to end up with a "thick" surfactant gel - is this impossible? I don't know the chemistry behind this, sorry.

Anonymous said...

Hello Susan,
I would not think that lye would be used in gels. I know it's the main ingredient in hair relaxers and hand made soap. have you ever thought about experimenting with hair relaxers? I would like to, specially the one with Calcium hydroxide, just a sugestion.

LSG said...

I made aloe gel yesterday, using Carbomer 940. Carbomer 940 took about 45 minutes to hydrate in water. I used Tetrasodium EDTA instead of lye water to raise the pH.

LSG said...

Sorry I meant to say that I used Triethanolamine (TEA) and not lye water to adjust the pH. Couldn't find a way of editing, so had to add another comment.

Susan Barclay-Nichols said...

Hi LSG! TEA works really well. (And I don't think you can edit a comment after making it. I know I can't!)

Hi Kathy! That can happen when you add a surfactant because they are electrolytes. You could use another surfactant because there are some that are better and worse electroyltes. I've made a product with C14-16 olefin sulfonate, cocamidopropyl betaine, and DLS mild that worked really well with the gel, so you will have to play with it.

Hi Rosi! It's not lye once it interacts with the gelling agent. (Sodium hydroxide, or NaOH, is a stronger base with a higher pH than calcium hydroxide or Ca(OH)2.) It's a great idea for a post, which I've just started writing. I haven't played with relaxers because it seems like something that requires a lot of work and could go so horribly wrong if you don't get it right. I'm apprehensive about making something that could cause pain if I do it wrong!

Anonymous said...

Chemistry is fantastic isn't it? Lye is used in soaps, hair relaxers, gels and even food according to the label on my lye bottle. Yes, i bought lye to make soap and it worked, i made some soap. It was an exciting experiment. Now here is the ingredients of a hair relaxer with lye,
I assume that the lye solution needs to be added at some point to the lotion, so how hot do you thing the lye/lotion should be in order to add them together?
Thanks for your concern and i would appretiate your advise. I will make it and try on my own hair and i just want to let you know that you are not responsible for whatever happens to my hair.

Aljonor said...

Hi Susan: I want to know if there is a difference between Carbomer and Acrylates/C10-30 Alkyl Acrylate Crosspolymer? I am in the process of making a gel to twist my hair with a soft hold. I have the c10-30, but did not know I had to thicken it, so I am going to re-visit that again after I purchase the TEA. But I don't know if I should add Carbomer to my cart. Thanks in advance. Aljonor

Susan Barclay-Nichols said...

Hi Aljonor! I've answered your question in today's Weekend Wonderings. The answer is complicated because there may or may not be a difference. Check the post!

Hi Rosi. I'm really really uncomfortable advising you to use lye in a hair product. I've never done it myself, and I'm worried I will tell you to do it wrong! I've e-mailed you some things that might help you formulate such a product.

And here's a little summary on ingredients you might find in what they call ethnic hair products (as if a certain hair type was the standard! Bah!).

Fatima Issa said...

Hi there Susan. I've been hiding in the shadows reading heaps of your articles. Whilst most of them go way way way over my head, I can't stop reading!
I have a question about this, and may be a bit of a silly question. But what do you mean by 18% lye solution?
Does this mean 1.6% total product weight is the water/lye solution, but that 1.6% solution only consists of 18% lye and the rest water?
Thank you :-)


Susan Barclay-Nichols said...

Hi Fatima! As I mention in the post, you would mix 18% lye with 82% water to make an 18% lye solution. You then add that at the suggested usage rate of 1.6%. So if you are making 100 grams of gel, you would use 1.6 grams of the 18% lye solution in the product.

Christine Higgins-Reid said...

Is there a 'greener' version for TEA, CAN i use something else other than the lye? Want to make some for my friends but they are worried about the lye straightening their curls!I have explained that it cannot do this at that strength but I cannot convince them. Can I make the gel and omit these 2 ingredients:? What will the disadvantages be?

Susan Barclay-Nichols said...

Hi Christine. If you don't use lye or TEA, you don't have a gel. You need the alkaline ingredient to make the carbomer turn into a gel. It looks like you could use tetrasodium EDTA to work, if you want. I think you can get that from the Personal Formulator. As a note, if your friends have ever used a gel from the store - including aloe vera gel - they've used a carbomer with lye or TEA in it. (Check the ingredients list!)

As I mention to Rosi above, it's not lye once it interacts with the gelling agent. It becomes another molecule, and one that is not able to straighten hair. And it certainly won't do it at such a low amount. (To straighten hair, it has to remain lye because we need that alkaline pH to make the straightening process work.)

Are they using hand made or cold process soap? If they are, they're getting about as much lye in that soap as they will be in the gel, which is to say none. The lye interacts with the gel creating a whole new ingredient.

My answer is generally this - if your friends won't use what you've made, don't gift it to them. Just think of how unlucky they are that they don't get to use your awesome, homemade products!

Lisa Reidzans Schmock said...

Hello! Boy, I sure do love your blog. Hope you can answer this. I found Sodium Carbomer - Preneutralized Carbomer at Lotioncrafter. If I'm reading it right, I shouldn't have to use a lye solution or triethanolamine? Am I correct? If so, any idea what the basic recipe would be then? I'm so bad at math ;/ Thanks in advance if you can help ;) Have a great day!

Susan Barclay-Nichols said...

Hi Lisa! You don't need to neutralize that. It comes in gel form and you would just add it to things that you wanted to be gelled. How to use it? Take a look at the recipes in the one ingredient, five products section of the blog that I'm writing this week! Here's the first page of that series. (Hit "newer post" to get to the next one!)

melian1 said...
This comment has been removed by the author.
melian1 said...

i wish there was an edit function so i didn't have to delete the comment just to add another sentence or two!

anyway, i have got some pre-neutralized carbomer from lotioncrafter, and it comes in a granular format, not already a gel. i just mixed it with water.

what i did was weigh out 4 little containers of water and added a different amount of the carbomer to see just how thick each amount was. then i took lots of notes so i know exactly how much i want to add to get what degree of thickness.

i don't know if i have got the same thing you are referring to, susan, or if i just bought it a long time ago and they've changed since then. it was a couple of years ago.

Lisa Reidzans Schmock said...
This comment has been removed by the author.
Lisa Reidzans Schmock said...

Hi melian1! I totally agree on the edit function, I'm a bit OCD with typos and such so I end up having to delete my posts and repost. Anywho, any way you can post the exact amounts of what you did, and the results? Looks like the preneutralized carbomer they have is still in powder form from what I read on the web site. I plan on getting some soon.

Dana Blanks said...

Hi Susan. Is there a reason you didn't use the fixative?

Susan Barclay-Nichols said...

Hi Dana! I don't know if I get your question. Do you mean the hair fixative, like the thing you'd use to create a hair gel? I have created a hair gel - check out this post - and used the fixative in that.

Vidyut said...

What neutralizers can be used with carbomer 940? Is it simply a matter of adjusting pH for gel formation or specific neutralizers? For example, if I'm planning to use Decyl Glucoside in a shampoo, which has a very high pH. Can I simply add carbomer 940 (wetted) to fix the pH of both as well as thicken?

Vidyut said...

To answer myself, yes. Did it to find out. Nice thick gel, nice pH.

benson in kenya said...

BENSON in kenya
if i were to make a thick gel using carbomer 940 say 10gms,edta 0.25gm,propyylene glycol 75gms TEA 125gm and distilled water 500gms does the formulation make sense,
if so can i use glycerine instead of propylene gycol

Susan Barclay-Nichols said...

Yes, you can use something else for the propylene glycol, but glycerin will make it much stickier than the propylene glycol. You can leave it all out and just water instead.

Curly Carli said...

Hello Susan,

Do you have a preference between using lye vs. EDTA for making gels? Is one more preferred or safe than the other?


Susan Barclay-Nichols said...

Hi Carli! I've never heard of anyone using EDTA to neutralize gels. Are you thinking about triethanolamine or TEA? (Someone commented above about this...) If you mean TEA, I do find that easier.

Joyce Camille Cabilin said...

Hi! I need help woth my serum formula
0.5% carbopol
1% TEA
0.5% phenoxyethanol
3% watermelon extract
0.8% fragrance
The rest is water.

Carbopol is added to water, t obe followed by TEA, it forms a gel, we add phenoxyethanol, extract and fragrance and stir.
Apparently it causes allergic reactions, we dont know the cause. We tried adding phenoxyethanol in water first before carbopol and tea but the results are the same.

Susan Barclay-Nichols said...

Hi Joyce! What do you mean by "allergic reactions". Have you checked the pH? Are you reducing it in any way? What about the fragrance? What's in the watermelon extract? Adding the ingredients in a different order is unlikely to change anything significantly, so the issue is likely with the pH of the product or one of the ingredients.