Hand Sanitizer Sodium Carbomer issue

With all the craziness going on I figured I might try to formulate some hand sanitizer as it seems to be liquid gold in light of the coronavirus. 

I ordered Sodium Carbomer and the company selling it advertised that it was good for using in hand sanitizer for thickening. Upon receipt I see they have updated their site to specify that it only works in a 70/30 ratio of 70% water and 30% Alcohol.... The CDC requires at least 60% alcohol for effective hand sanitizing. 

This works great with water, but after adding alcohol it loses viscosity. Does anyone know if there is a way to get this to thicken with higher levels of alcohol? 


  • Bill_TogeBill_Toge Member, Professional Chemist
    yes: use more of it
    UK based formulation chemist. Strongest subjects: hair styling, hair bleaches, hair dyes (oxidative and non-oxidative) I know some stuff about: EU regulations, emulsions (O/W and W/O), toothpaste, mouthwash, shampoos, other toiletries
  • Use another thickener that can take the 70%. You can try Sepimax Zen. Assuming you are only using it for yourself and can take the cost of it. 
  • If you need a stiff gel you're going to need to change carbomers; some varieties are designed to work in higher concentrations of ethanol.

    However, I've tried carbomers around your tolerance and found that a flowable gel very similar to hand sanitizers I use personally happens around 55%wt ethanol. 

    It's hard to give you more advice without knowing how much carbomer you're using.
  • Acrylates/C10-30 Alkyl Acrylate Copolymer is good for this (one of many available Carbopol grades).

    What are you neutralising with? This can make a big difference in hydroalcoholic systems - TEA or AMP will work much better than NaOH
  • @Bill_Toge I will try adding more. 

    @LincsChemist Acrylates/c10-30 is double the price. What about Carbomer 980? 

  • lewhitaklewhitak Member
    edited March 2020
    I have a 70% EtOH hand sanitizer formula using 1% Carbomer 980 and we have issues with balling while rubbing the gel on your hands. Very nice gel, though--clear and thick.

    Neutralization is done with AMP. 

    The Carbomer 980 isn't rated highly by Lubrizol on their comparison charts between the carbomers for not having issues with fish eyes/balling, so that might factor in to your choice. 

    We had bulk in 980, so that's why I ended up using it. However, I could definitely be missing a step here! Maybe a processing change would help with this.
  • @Bill_Toge adding more didn't work. It just glumps into white blobs. 
  • Am having the same problem. First I tried,
    Glycerin 3%
    Xanthan Gum 0.4%
    Water 26%
    Isopropyl Alcohol 70%
    It looked good until about 40% of the alcohol was mixed in, then it started going stringy. I have since learnt that to use xanthan it would have to be xanthan CGT, I only have CG. 

    Then I tried 
    Glycerin 3%
    Ultrez 10 0.25%
    Water 26.5%
    Tried both Triethanol and Suttocide A to neutralise. both failed.
    Isopropyl Alcohol 70%
    This didn't work either, just stayed liquid. 

    Have seen a Belinda Carli vid that said Seppimax Zen would work but it seems to be sold out of everywhere I have looked (live in Australia and tried Aussie Soaps and New Directions). 

  • You will need the suitable neutralizer for the carbomer. 

  • @LincsChemist Acrylates/c10-30 is double the price. What about Carbomer 980? 

     0.3%-0.4% works fine. sepimax zen require more & cost more. other polymer required more qty.  Every polymer cost you more for now.
  • @LincsChemist so .3-.4% Acrylates/c10-30 will work to thicken? 

    Can I still use Triethanolamine to neutralize at 70% ? I have that already. 
  • It depends on  how thick you want. Try
  • @ajw000

    Should do, I've made one at 0.6% Ultrez-21 which is fairly thick. I think at 70% ethanol the polymer salts may start to precipitate out with TEA - you'd probably want to use AMP in that case, but I'm only working from the same table that @jemolian kindly posted. 
  • @ajw000

    TEA didn't work for me with carbomer 980 in a 70% ethanol product. The polymer started to salt out. AMP did work just fine. 
  • @LincsChemist - I ordered  Acrylates/C10-30 Alkyl Acrylate Crosspolymer, what % alcohol did you use to make yours? 
  • FekherFekher Member, Professional Chemist
    @lewhitak TEA can just lead to 60 % Alcohol as maximum for alcoholic gel. 
  • ajw000ajw000 Member
    edited March 2020
    Hey guys, I'm having difficulty with thickening. Can anyone point me in the right direction?

    Alcohol 91%28.0
    Acrylates/C10-30 Alkyl Acrylate Crosspolymer

    This was nice and thick before all the alcohol was added, but watered down after 28g alcohol. I tried adding .2 more triethanolamine with no affect, I then tried adding .1 more Acrylates/C10-30 Alkyl Acrylate Crosspolymer with no affect. 

    Other Ingredients I have readily available: 
    Propylene Glycol 
    PEG-40 Castor oil 

  • PharmaPharma Member, Pharmacist
    If you have a look at the table @jemolian posted, TEA won't work for your 77% v/v.
  • @Pharma its 63.7 solution, not 70%
  • PharmaPharma Member, Pharmacist
    Ups... haven't seen that you use 91% ethanol. Still results in 70% v/v.
  • ajw000ajw000 Member
    edited March 2020
    @Pharma 28 x 91% = 25.48

    25.48/40.4grams= 63.07%  weight volume(I missed a zero last time). How do you calculate v/v? Also, is the fda looking for w/v or v/v labeling requirements? WHO suggests at least 60% for effectiveness, is that w/v or v/v? 

    @LincsChemist what alcohol% did you use when using ultrez-21? Any suggestions? 
  • PharmaPharma Member, Pharmacist
    edited March 2020
    63% w/w equals 70% v/v. WHO uses v/v and nobody uses w/v any longer (except probably the US cause they also stick to imperial measurements without reason).
    BTW I don't calculate due to volume depression but go with conversion tables, a lot faster and easier ;) .
  • @Pharma where can I find conversion tables? Thanks! 
  • Ok, I think I got it. But I am having trouble converting my grams to ML ratio for volume. Can anyone show me how to calculate? 

    Water: 23.4g
    Alcohol 91%: 42.7g
    Aloe: 1.3g
    Glycerin: 1.6g
    Acrylates/C10-30 Alkyl Acrylate Crosspolymer: .3g
    Triethanolamine: .2g

    Total Grams: 69.5

    I found online that .785g of isopropyl alcohol= 1ml 

Sign In or Register to comment.