Home Cosmetic Science Talk Formulating Behentrimonium Methosulfate in hair conditoners

  • Behentrimonium Methosulfate in hair conditoners

    Posted by VinTec on March 23, 2023 at 8:20 am

    Hi there!

    Lately I’ve been using a lot of BTMS (Incroquat Behenyl TMS 25%, which is a blend of Behentirmonium Methosulfate and Cetearyl Alcohol) in hair conditioners/masks, as my manager likes this ingredient and asks for me to use it. But there’s something I noticed: sometimes the result it’s not really pretty… It seems that BTMS it’s not fully incorporated and the product doesn’t seem homogeneous (there’s some clumps in the emulsion).

    The standard process is: We add the water and oil phase (BTMS belonging to the oil phase) at the same beaker, heat it until ~80ºC an then homogenize under 800 RPM for 5-10 minutes. Then we add other phases (silicones, actives, fragrance, preservative system) and follow with the homogenization.

    I tend to use it at a 2-4% rate and sometimes combine it with Cetrimonium Chloride and Stearamidopropyl Dimethylamine. I also combine it with some fatty alcohol (cetyl or cetearyl alcohol) at 5-6% rate and silicones (mainly dimethicone and amodimethicone).

    Does anyone here have worked with BTMS before (or works with it) and noticed the same thing? Is there some incompatibility or particularity when working with this ingredient?

    Kind regards.

    Trng1122 replied 8 months, 2 weeks ago 7 Members · 12 Replies
  • 12 Replies
  • chemicalmatt

    March 23, 2023 at 3:25 pm

    Add the BTMS to the water phase directly at 85 - 90C. Once dissolved/dispersed, then add remaining surfactants, lipids, builders in that order or as a separate oil phase. Cool slowly and mix slowly while cooling. Adding CETAC is not advisable, nor is homogenizing. Best way to crash a cationic emulsion: high shear. If you must add STPDMA, not a bad idea, add the neutralizing acid to the water and BTMS liquid first, then add the STPDMA with the oil phase or even directly allowing plenty of time to melt/blend/neutralize. Lactic acid works way better than citric acid too.

    • This reply was modified 11 months, 1 week ago by  chemicalmatt.
    • VinTec

      March 28, 2023 at 7:58 am

      Thank you for the heads up, Matt!

      Why CETAC is not advisable in this situation? I’ve thought that I could achieve a good conditioning effect using both.

  • chemicalmatt

    March 28, 2023 at 2:47 pm

    CETAC is redundant. You already have two superior quaternary alkyl compounds in there, both which add emulsification and hair sensorial conditioning. CETAC functions quite well as an inexpensive cationic emulsifier. As for conditioning: meh!

  • Hairlover

    May 21, 2023 at 5:56 pm


    I don’t know if this topic is the correct one for my formulating problem because I don’t know if the primary cause is BTMS.

    I’m working on a leave-in conditioner with SPF protection.

    Draft formula:

    Phase A

    Behentrimonium methosulfate (80%)= 2.2%
    Ceteary alcohol= 2.0%
    UVA filter (Diethylamino Hydroxybenzoyl Hexyl Benzoate= 2.0%
    UVB filter (ethylhexyl methoxycinnamate)=3.0%
    Dimethicone 350= 2.0%

    Tocoferol= 0.05%

    Phase B

    Cetrimonium Chloride (25% solution)= 3%
    Na EDTA= 0.1%

    Phase C

    Ciclomethicone= 1.0%
    Panthenol 75%= 2.2%
    Benzyl Alcohol+ Dehydroacetic acid= 0.6%
    Hydrolized protein (20% solution)= 1.0%
    Hydroxy Propyl Methyl Cellulose= 0.4%
    Glycerin= 2.0%
    There is a slight separation on the bottom when I put the product on a centrifuge at 3000 rpm for 10 min. It looks like a small drop of water.

    I have tested a lot and come to a conclusion. If I make an emulsion and add all the above ingredients except Hydrolyzed proteins and the preservative - the emulsion is stable. If I add or preservative (Benzyl Alcohol+ Dehydroacetic acid) or hydrolyzed proteins or both - a drop of something (probably water) occurs on the bottom of the centrifuge tube.

    So it’s probably something wrong with the interaction between proteins/preservatives and the emulsion itself.

    What is the cause of this separation? I have tried so many things:

    -More or less emulsifier

    - More thickener of water/oil

    - Other hydrolyzed proteins

    -More /less homogenization in the process

    Based on my theoretical knowledge all the above ingredients are compatible.

    If any of you have any idea what is wrong. Please help.

    Best regards

    • Perry44

      May 22, 2023 at 8:30 am

      There is a lot wrong with this formula but the main problem is that you are not using the appropriate emulsifier for the oil system you’ve chosen. (I don’t know what that oil is because you just wrote oil. They are not all the same).

      You are also adding ions to a charged emulsification system which leads to instability. So, the best thing to do would be to use standard preservatives like Methylparaben which have no problems in emulsions. Using the preservatives you’ve suggested leads to the problems you’re experiencing. Salts and other ions + ionic emulsifiers don’t work well together.

      You also should use a suspending agent like Carbomer (or Xanthan gum) to help with stabilization.

      • Hairlover

        May 22, 2023 at 6:28 pm

        Thank you for your reply and help. I appreciate it – really.

        The oils are coconut oil and argan oil.

        Which emulsifier do you suggest or will fit more for the chosen oil system?

        As for preservatives – noted. I will use methylparaben.

        What exactly do you mean by suspending an agent? I used Hydroxy Propyl Methyl Cellulose for the matter of water phase thickener and overall stability enhancer. Is this a bad pick for the whole emulsion system? Should I use another- like you suggested carbomer?

      • paprik

        May 23, 2023 at 3:20 pm

        Hi Perry,

        I thought anionic substances (such as Carbomer or Xanthan Gum) are not compatible with cationic substances?

        Wouldn’t the HPMC be better?

        Thank you for confirming 🙂

        • Perry44

          May 24, 2023 at 7:26 am

          Better would be HEC for a cationic system. Sorry I didn’t see the cetrimonium chloride in there.

    • VinTec

      May 23, 2023 at 11:38 am


      Probably the hydrolyzed proteins and preservative system don’t work well in your formulation; they’re causing incompatibility.

      The most practical decision would be to change the hydrolyzed proteins and preservative system. Overall I like to use Microcare PHG (which is a caprylyl glycol and phenoxyethanol blend). Also, would it be possible to change the hydrolyzed proteins for other ingredients? Aminoacids blend or plant extracts would do the job 🙂

    • ketchito

      May 23, 2023 at 10:28 pm

      Is your viscosity ok? It seems it might be a bit too low. Perhaps you could increase the Cetearyl alcohol to improve the stability.

      • Hairlover

        May 24, 2023 at 2:01 am

        Hello to all formulaters,

        Firstly thank you all for you replies.

        As you suggested above, I have tried:

        - Different preservative system.
        I have tried with the metyl paraben (disolved in propyene glycol and added in C phase) and blend of Phenoxyethanol and ethylhexylglycerin. The results was the same. Water or some other liquid on the bottom. Maybe the problem is really too low dosage of cetearyl alcohol and HPMC?

        The viscosity is really a bit low, but the Cetrimoum Chloride makes it harder to increased it. Maybe there is some hack how to solve this problem or the solution is to just add a lot of thickener?

        Note: I didn’t include any proteins and the emulsion without preservative was stable.

        Photo on the left: with addition of metylparaben , on the right with the addition of Phenoxyethanol and ethylhexylglycerin.

        note: The difference of the colour is from the different mixture of oils (more argan on the left).

        Any suggestion what is wrong and what to try next?

        • This reply was modified 9 months, 1 week ago by  Hairlover.
        • This reply was modified 9 months, 1 week ago by  Hairlover.
  • Trng1122

    June 16, 2023 at 2:00 pm

    I used to have the same problem but i increased the btms to 3.3%, added another thickener wax, had HEC 0.4% hydrated in water phase and this was solved. I did all the adjustments as they suggested me here. Hope this will help you.

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