Home Cosmetic Science Talk Formulating Increasing pH in a prepared emulsion?

  • Increasing pH in a prepared emulsion?

    Posted by AVisotsky on May 5, 2020 at 3:43 am

    Hi folks,
    Any way to neutralize glycolic acid in an emulsion that is already made?
    Making an emulsion with glycolic acid. Came out way too strong (2.5 pH). For my home use, so I did not add a preservative. 
    formula:

    %%, weight
    Water the rest
    glycolic acid  8.3
    Caprylic Capric Trygleciride 30
    Montanov 68 4
    Propanediol 5
    Behenyl Alcohol 2
    AVisotsky replied 4 years ago 2 Members · 4 Replies
  • 4 Replies
  • AVisotsky

    Member
    May 5, 2020 at 5:42 am

    Oh wait, I just realized it is w/o, so it doesn’t really have a pH, right? So I can’t measure it correctly unless I measure the pH of the water phase ahead of time? 

  • AVisotsky

    Member
    May 5, 2020 at 5:57 am

    Ah, no! It is actually o/w, it’s miscible in water and not in oil, just checked.:) 

  • ngarayeva001

    Member
    May 5, 2020 at 8:27 am

    Why would you be checking whether it’s miscible or not if you know what are the ingredients? This method is not as reliable as it sounds and is only useful if you don’t have a list of ingredients (I can give you examples of o/w sunscreens that are absolutely not miscible with water yet it’s o/w). You can’t get W/O emulsion when you are using O/W emulsifier. Add NaOH and a preservative. I wouldn’t trust unpreserved emulsion with pH >3.

  • AVisotsky

    Member
    May 5, 2020 at 6:20 pm

    @ngarayeva001 Hello and thank you. Because I didn’t know to look up what kind of emulsifier Montanov 68 was :) I realize my mistake now.
    Thank you for the tip. Is NaOH added before emulsification or could it be added after? 

Log in to reply.