Home Cosmetic Science Talk Formulating “aerated” batch

  • “aerated” batch

    Posted by natchemist on January 12, 2014 at 10:23 am

    Hi all,

    I have this O/W emulsion with polyglyceryl 3-stearate (low HLB) and polyglyceryl 10-laurate (high HLB) as emulsifiers. I have cetearyl alcohol and stearic acid for consistency/thickening and other ingredients like IPM, capric caprylic triglycerides and olive oil.
    My issue is that at RT, my batch looks nice and smooth at the surface, but when I spread it on a paper it looks uneven and specific gravity is too low (0.92).
    My final pH without adjustment is 4.00 and I’ve been adjusting pH up to 5.5 with NaOH once it’s at room temperature.
    I’m thinking this emulsion is not stable and what I can do is add the required amount of NaOH when combining phases at 75°C to form NaStearate..maybe that can help. When I add NaOH my batch initially looks green-yellow and then goes back to white…why is that?  Could forming the in situ emulsifier at a high temperature help stabilize the batch?
    Chemist77 replied 10 years, 10 months ago 3 Members · 4 Replies
  • 4 Replies
  • Chemist77

    Member
    January 12, 2014 at 12:06 pm

    what is the approximate viscosity???

  • natchemist

    Member
    January 12, 2014 at 3:07 pm

    Like 150,000 - 200,000 cps

  • OldPerry

    Member
    January 12, 2014 at 6:56 pm

    to figure out what is causing the color change, we’d need to know all the ingredients in your formula.

  • Chemist77

    Member
    January 12, 2014 at 9:22 pm

    @joseg I have had the same issues with stearic acid emulsion, suggest you add a very little quantity of either ceteareth-12 or 20 and check the structure of your emulsion again. In my emulsions you can say the ethoxylated fatty alcohol irons out the wrinkles of my stearic acid emulsion and makes it uniform. Once you have a desired appearance we move on to your other problem. Although I have slightly different formula but no harm in trying. I use Ceteareth-20.

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