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@ProfessorHerb Besides the occlusive and humecting ingredients, emollients (like isopropyl myristate or caprylic/capric triglyceride) help complete the combo.

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@GeorgeBenson This is just a guess, but some molecular complexes have a metal ion as part of the structure, emiting light at a specific range (color). When you remove the metal ion (for instance, by chelation from your phytic acid), then the absortion pattern changes, changing also the resulting color. 

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@Lab As @PhilGeis mentioned, hair turning green in the swimming pool is due to the oxidation of copper present in hair (usually as part of dying), and it’s prevented by using a chelant such as EDTA (you need to add more then usual to have a good performance). 

In the case of chlorine, I’m not sure it binds to hair since it’s very water soluble so you better just focus on chelating copper.

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Stephanara said:

ketchito said:

@Stephanara After adding sodium hydroxide, check for any instability (put a sample in the fridge). I think you’re using a bit too much salt for that level of LABSA, and that ingredient is a salt-phobe, so to speak.

Thanks @Ketchito. Will do as you advised
 But what should I watch out for and what percentage of salt do you think I should try out

If you put a sample in the fridg, the product should remail clear. If on the contrary it starts getting turbid, and then this turbidity settles, that’s probably your sulfonate salting out (you’ll notice it’s quite some amount of material that settled at the bottom).

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@Paprik Not sure if it’s feasible, bit if you have access to a nitrogen tank, you could flush out air from your bag with nitrogen….unless your bag is too big ????

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@rrthae Cocamide MEA and Coco Betaine (or Cocamide DEA and CAPB) have high affinity with a strong viscosity response, regardless of the anionic. I believe that if you add SCI at the start and then one of the other surfactants (especially Betaine), the mixed micelles formed will preferentially have a mixture of SCI and Betaine, which might not give such a strong viscosity response.

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@chemicalmatt You made turn to the “dark” (or bright) side, hehe. I’ve been a fan of Carbopol for years, but I’ll try 3V Polygel’s now????

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@MattTheChemist Could you be more specific when talking about aqueous/polyol base? I’m not sure if you managed to make an emulsion or a suspension. If it’s the later, not sure that adding an oil soluble antioxidant might help.

Also, what sign of oxidation you’re observing?

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@Stephanara After adding sodium hydroxide, check for any instability (put a sample in the fridge). I think you’re using a bit too much salt for that level of LABSA, and that ingredient is a salt-phobe, so to speak.

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@Zahra I understand you want to make a hair straightener. For that, the common actives are thioglycolates and carbocysteine (although not as potent as thioglycolates). Formaldehyde was used in the past, but has been withdrawn due to safety issues, especially for hair dressers. 

Hydrolyzed keratin doesn’t perform any significant role in these products. Consider that the ingredient is hydrolyzed in order to the added to a cosmetic, which means, rather than having the full protein (which can have film forming properties), you have smaller pieces (mostly in the form of peptides). They can have many different molecular weights, but they are also more water soluble than the protein,which makes the chance of interacting with hair very low. 

I’d advise you to focus more on the straightener’s stability in your formula, and the conditioning agents, rather than the keratin (which you can find from many suppliers).

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@Camel It’d be advisable as well to check the technical info in Lubrizol site. They even have a chart where it shows the different viscosity and consistency expected with each of the Carbopol polymers.

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@Amira You might search for a couple of books that have good content for the topic: “Conditioning agents for hair and skin” and “Chemical and physical behavior of human hair”. 

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@Newtoformulating Are you using AMP to neutralize your Acudyne 1000?

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@Abdullah At a pH between 4-5, you’ll have trisodium EDTA instead of tetrasodium EDTA. 

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@Zahra I’d remove Glycerin, add some silicone and replace your cationic surfactant for one with longer chain (like Behentrimonium chloride) at a bit higher level.

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@Lva Ideally, you’d better use more sulfonic than SLES (it boosts foam and detergency), but you’ll need to check the amount of salt used (sulfonate is not a big fan of salt). 

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Abdullah said:

ngarayeva001 said:

Not directly related to the question but I believe tetrasodium EDTA is to be used in basic not acidic products. You probably need disodium.

A lot of people say so but they don’t say the reason for it and for several reasons i believe this may not be true. 

1. The EDTA part chelates the metals not the sodium part. Sodium only increases the solubility like it does is sodium benzoate and sodium methyl Paraben.
So why would it matter if it has 2 or 4 sodium while there is a lot of sodium in the product anyway?

2. A lot of shampoos have tetrasodium EDTA but pH is not basic like this one 
https://phique.com/product/phique-moisturizing-shampoo/

It’s because of the dissociation constant of each carboxylic group in EDTA. Generally speaking, at a pH higher than 10, your structure will have those 4 carboxylic groups in the anionic state and ready to complex with metal ions. At a pH below 6, you’ll only have 3 (one will be protonated by H+); at pH below 3, you might have only 2 available carboxylic groups in the anionic state…which is basically disodium EDTA. 

One reason to use tetrasodium EDTA in a product with a pH lower than 6 is both it’s availability and current price compared to disodium EDTA. 

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@HexaManna Even though some small molecules could deposit on fabrics and give some lubricity (like some esters), the benefits are not comparable to those of cationic surfactants, more especifically dialkyl quats from tallow, which is the most common ingredient used in fabric softeners.

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@Rimbaud16 It could also be an issue with the plasticizer migrating to the bulk. I usually see anhydrous formulations in PET bottles. Could you make a test with PET bottles?

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@Syl You can find the latest european regulation for Behentrimonium chloride here: https://ec.europa.eu/growth/tools-databases/cosing/index.cfm?fuseaction=search.details_v2&id=92331.

I believe this is the one that the formula you mentioned takes into account. Btw, the 3% according to this regulation is for leave-on hair products. for rinse-off, the max is 5%. 

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@1Armand2 I believe @Abdullah‘s comment was if Phenoxyethanol as sole preservative was enough. Phenoxyethanol lacks activity against mold and yeast, and that’s why it’s usually paired with organic acids. 

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As @Microformulation, hair conditioning is a broad topic; for instance, cationic deposition cannot only be regarded as a charge-driven phenomena since all cationic molecules are different (for instante, stearamidopropyl dimethylamine needs to be neutralized for deposition on hair, and depending on the acid used, that might lead the formula to an acidic pH). Keep in mind that the isoelectric point of hair is below 4.0, so pH above the IP will already have hair with negative charge. 

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@tecnico3vinia Yes, adding a rheology modifier that gives you high yield value will help suspend pearlizer. Also, achieving a good viscosity also helps prevent sedimentation of the pearlizer. 

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@MurtazaHakim What’s the pH of your formula? I don’t have much experience with CHG, but I found some information where it says that CHG could precipitate at a pH outside the range 5.5-7.0 (https://www.supleasepticos.com/wp-content/uploads/chg-compatibility-.pdf).

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@Paprik Just out of curiosity, did you add some base before adding surfactants (and after mixing and hydrating the polymer)? Since these polymers are highly hygroscopic, manufacturers add a layer of acidic mantle to “delay” hydration (that’s what the “R” stands for when you see the material code). So, adding a base helps get rid of the mantle, speeds hydration, and increases both viscosity and clarity. But mainly, it helps the polymer to expand, and this is crucial since when you add surfactants, there’ll be no room for the polymer to expand properly and interact with surfactants (a lack of polymer expansion might prevent a proper polymer-surfactant interaction, causing separation).