Xanthan Gum and Hydroxypropyl Cellulose precipitate in surfactant mixPosted by letsalcido on May 11, 2020 at 6:19 pm
Like the title says. I was experimenting with those two gelling agents to thicken a face wash.
I tried a few combinations of Decyl Glucoside, Coco-Glucoside, Cocamidopropyl Betaine. I was avoiding anionics for their “harshness”.I’ve tried adding the Hydroxypropyl Cellulose directly into the final product and hydrating it before adding the surfactant mix. It always ends up looking turbid, and the gel precipitates after a while.I tried Xanthan Gum Clear (from lotion crafter) and added it directly to a final surfactant mix (by slurring), same result. Didn’t thicken it, seems like it didn’t fully hydrate and precipitated.
I have seen formulas for different soap and detergent mixtures (including CAPB) that use Xanthan or HPC.
If there’s some chemistry I’ missing here to understand why it’s failing I would love to know. I had already added my essential oils and PEG-40 HCO.
MemberMay 11, 2020 at 6:56 pm
I tried a few combinations of Decyl Glucoside, Coco-Glucoside, Cocamidopropyl Betaine. I was avoiding anionics for their “harshness”.
- “anionic” and “harshness” are not related. You chose horrible surfactants in my opinion.
MemberMay 12, 2020 at 3:33 am
Thanks for the reply @Belassi
I certainly have a lot to learn, they don’t teach this stuff in a biochemistry program.
My understanding is that anionics in general tend to be much better cleansers and degreasers, which can be bad for a person with oily or combination facial skin. Perhaps they don’t all cause irritation like SLS, but they could strip too much of the natural skin barrier for a person prone to acne. Is this wrong or somewhat correct?I’m here to learn to the professionals and open to learn about your preferred ingredients. I also have SLSa, and getting a sample to play with of Olivem 300, PEG-7 Glyceryl Cocoate (probably very similar to Olivem 300 I would assume).Any input on the issue I’m having with the thickeners?
MemberMay 12, 2020 at 11:56 am
well you tried to avoid anionics surfactants but gums can have ionic character too! xanthan gum is anionic. What pH is your product at? CAPB is amphoteric which means the pH influences the ionic character.
Try looking for products that have the surfactants you’ve chosen (and only the surfactants you chose) and I think you’ll notice two things
1. you’ll be able to see what ingredients are being used to thicken systems like yours
2. you’ll notice most products don’t have just your surfactants because it wasn’t popular either in terms of feel or performance.
Other piece of advice it to post your formula (percentages and all). People can spot missteps easier this way
MemberMay 12, 2020 at 3:18 pm
Surfactants vary greatly in their cleansing ability. SLS is one of the stronger ones. While it’s true they can strip lipids from the skin, that’s why we design using a combination of surfactants. PEG7GC is a refattener, used mainly to counteract that effect. I can’t say why you’re having trouble with the thickeners. I use PEG-150 distearate and CMEA.
MemberMay 12, 2020 at 5:30 pm
@EVchem thanks for the reply! This is a formula of a body wash I just made and it also had issues with Xanthan Gum.I know other compounds can have charges, but I explained my (perhaps wrong) reasoning for not choosing anionic surfactants for my face wash. I don’t expect all anionic compounds to be stripping.
I don’t have the face wash formula handy but this body wash I threw together also had issues (I went with a mostly “natural” formula:
Castile soap - 40% (very rough calculations 8% active total)Coco Glucoside - 10% (5% active)
CAPB - 20% (7% active)
Glycerin - 4%Xanthan Gum - 0.3%
Phenoxyethanol - 0.5%
Eukyl 900 - 0.5%Essential oils - 0.6% (tangerine, mandarin, grapefruit and a bit of geranium, so it doesn’t smell strong since it’s mostly citrus)
PEG-40 HCO - 2.5%
For this formula I slurried the xanthan with the glycerin and added to the final product. The consistency was good before the thickener, but I like more viscosity so I can pour it onto my hand and won’t drip.Before anyone asks how I calculated the active in my liquid soap: 1kg of Olive and Coconut oil in a final 5kg batch. I know there are unsaponifiables, and I did use excess POH. Now that I think about it a 20% active is generous primarily because of the glycerine produced, so that is for sure not in the calculation but may only account for 2-3% removed from that 20%? I’m not trying to make a commercial formula with this though, I’m happy if I can replicate it.The pH of my different experiments has been ~6.Just noticed, I’m not using Hydroxypropylcellulose, I’m use Hydroxyethylcellulose. Although not in the recipe I listed here, so I’m happy to just focus on Xanthan Gum. The issue was present with both.@Belassi It’s been incredibly hard finding free resources of technical data or theory about this kind of information. Maybe I’m not looking in the right places, but I have a science background and would much rather learn the hard chemistry behind this all so I don’t make “bad” choices. So far, however, it all seems more empirical to me. What I understand so far:
- anionic surfactants are used for their cleansing
- amphoterics for mildness, foam boosting and making anionics milder, and thickening anionic systems
- cationics for conditioning effect due to adhering to skin and hair by electrostatic forces.
- nonionic milder cleansers, less stripping. Compatible with any of the above.
I read CMEA is an older option to cocamidopropyl betain and hydroxysultaine. What are your opinions on these three, which one is better performing?As for PEG-150 distearate, I have some coming to me and will try it if everything else fails. But I mostly wanted to replicate a Parsley Seed antioxidat face serum I really like that uses it for thickening. It costs $75USD for 100ml, so I’m better of making it myself. (Ingredients: Aloe Barbadensis Leaf Juice, Water (Aqua), Polysorbate 80, Sorbitol, PEG-150 Distearate, Polysorbate 20, Benzyl Alcohol, Phenoxyethanol, Lavandula Angustifolia (Lavender) Oil, Panthenol, Disodium EDTA, Citric Acid, Sodium Citrate, Camellia Sinensis Leaf Extract, Dehydroacetic Acid, Ormenis Multicaulis Oil, Vitis Vinifera (Grape) Seed Extract, Carum Petroselinum (Parsley) Seed Oil, Linalool, Limonene, Geraniol).But I digress, I’m trying to see what I can achieve with the least amount of PEGs as possible given the bad rep they are getting. While I’m currently experimenting for my own use I may consider commercializing my formulas in the future, so might as well keep that in mind.
MemberMay 12, 2020 at 6:06 pm
I read CMEA is an older option to cocamidopropyl betain and hydroxysultaine. What are your opinions on these three, which one is better performing?
That would surprise me. CMEA is not that soluble. The practical limit is around 2% or under; I use 1.5% as a foam booster and thickener. I’ve not tried hydroxysultaine so I cannot comment on it.
MemberMay 12, 2020 at 6:45 pm
I don’t think I can directly speak to precipitation, but I have made many batches of a product that uses both xanthan gum and HEC.
HEC will hydrate well enough on its own over time, xanthan is kind of a pain. I recommend using shear mixing if possible, and giving it plenty of alone time with water, which would mean adding it prior to surfactants. It sounds like in both your methods you add it to the end.
This is just how we’ve used it. I have never seen precipitation. I don’t know if it provides the best texture for a face wash… sort of more slimy. If possible I think the best way to get a thick cleanser is still anionics and salt.
MemberMay 13, 2020 at 12:02 pm
The lower your pH, the more cationic your CAPB will act, that could be causing the problem with the xanthan gum.
If you want to read more on HPC skim through the file I attached
MemberMay 13, 2020 at 11:04 pmletsalcido said:The pH of my different experiments has been ~6.I am not sure if you used castille soap in all of your experiments but in the example formula shown you have. Soap is not stable at a pH of 6 and will break down into the fatty acids at this pH (there are many discussions in this forum regarding this if you search).My thoughts are that the cocoglucoside is helping to solubilise the fatty acids but not enough to maintain a clear solution.Try the formula without the soap and see if that helps.
MemberMay 18, 2020 at 1:57 am
Thank you everyone for your input!
@EVchem CAPB has been the common variable, I think that’s probably where this is headed. At any rate, I am now convinced that you just can’t achieve the same sensorial profile without PEGs. The products I like the most and was using as benchmark all had PEGs.@ozg the formula with the soap was after several failures with other surfactants. I added the soap because it’s anionic and I could thicken it more easily. I didn’t know about the stability of the soaps. Thanks for pointing that out. I have seen a few “natural“ direct to consumer brands selling gel washes and shampoos where they use soaps as their only anionic. I’m guessing the stability issue is a more long-term one? If the product stays stable for at least 3-6months I’m guessing that’s fine for a brand that doesn’t have product sitting on the shelves.
Also, the pH 6 is from paper strips. I just bought a pH meter since I think the strips are more unreliable than I had originally thought!