Home Cosmetic Science Talk Formulating Carbopol 940 lumps when rubbed in

  • Carbopol 940 lumps when rubbed in

    Posted by haktar on March 23, 2020 at 11:29 pm

    with all that’s going on I’ve made numerous attempts to create a nice hand sanitizer gel using carbopol 940 just for my use and my partners, I’m getting really close now its a pretty basic formula just

    134g 99% IPA
    65g Boiled Water
    1g Vegetable Glycerin
    0.7-1g Carbomer

    I use Triethanolamine to adjust the ph and I get a really nice clear gel however when she rubs it into her hands it produces little lumps that don’t appear to be in the gel, I don’t experience it as much however if I rub some in a concentrated spot quickly the lumps start to produce. I originally started with 8g of glycerin and I have been reducing it because I assumed it was the culprit although my last batch contained no glycerin and I had the same results, I also attempted adjusting the amount of carbopol I was using and i did receive less or more lumps depending on the amount used so I’m guessing that’s the problem.

    I just don’t know the solution, I’ve tried dispersing the carpobol in water at different temperatures, in alcohol first, tried making a paste then adding the rest, I’ve tried a magnetic mixer and also a fast blade mixer, mixing for over an hour and letting the carbopol wet for about 30 min, I’d really appreciate a tip from the pros.

    I should mention I’m using tap water as its just for us, I live in Scotland we actually have really good water its about 6.9ph 40ppm

    em88 replied 4 years ago 5 Members · 6 Replies
  • 6 Replies
  • belassi

    Member
    March 24, 2020 at 1:16 am

    If I am making sanitiser I normally leave 940 to hydrate overnight.

  • haktar

    Member
    March 24, 2020 at 11:16 am

    I thought that might have been my issue, perfect, do you know if you can keep the solution mixed for a good while? Just carbopol and water. 

  • alchemist01

    Member
    March 24, 2020 at 12:59 pm

    “Balling” is a common phenomenon with carbomer. Some formulas actually do it on purpose to create a soft exfoliant (http://colinsbeautypages.co.uk/skin-peeling-from-peeling-gels/).
    From what I’ve read it happens because carbomer is hydrating with skin’s moisture on contact and create tiny gel clumps. This is usually because there’s too much carbomer in a formula, but I get the feeling that’s not your issue. You probably just aren’t letting it hydrate enough. I’ve been told a million different ways to go about doing that, I would just experiment with what works for you.

    Also I recommend distilled water whenever possible.

  • em88

    Member
    March 25, 2020 at 8:26 am

    Pretty sure you are not dispersing carbomer properly. 

  • chemicalmatt

    Member
    March 25, 2020 at 9:08 pm

    Standard carbomers make lousy alcohol:water gels, period, no matter how well you hydrate them. This is why everyone who manufactures these gels commercially  - like my company - uses Acrylates/C10 -30 Alkyl Acrylates Crosspolymer (Ultrez-21). Now 3V Sigma USA has developed an acrylic/PEG co-polymer called RapidGel EZ1. That stuff outperforms them all. If only 3V Sigma could make it fast enough to supply us all during this COVID-19 crisis! They are steady trying though.

  • em88

    Member
    March 26, 2020 at 7:56 am

    Carbomers can be used to make good gels with high concentrations of alcohol if the method is done right. 

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