Issues with stability of an acidic solution

Hi to all !

I am having issues maintain stability for an acidic formula. I am suing the traditional hydroxucellulose and cetearyl alcohol ceteareth -2o . After formulating the formula looks fine- though after a week it starts to loose its viscosity and thickness.

I usually don't heat up he cellulose to 75 degrees- is it criticall?
Should I increase the water phase acidity pre to additng the active acid ingredient?

PLEASE Help me out. I am lacking the knowledge to solve this by myself.


  • Hi Keren! pH of the formula? And maybe acidity of the mixture? I usually go with xanthan gum at acidic media.
  • round 2 . Thanks for your replay...
  • chemicalmattchemicalmatt Member, Professional Chemist
    If you are using HEC, and not heating, then it is wise to allow 60 minutes mixing time, then add a TINY bit of alkali (AMP-95, NaOH 1.0%, ) to swell. Then proceed as usual. However, if you have a LOT of electrolytes in there at that low pH,  ChrisV's recommendation is best, and dehydroxanthan works best when you are at really low (pH2.0?) 
Sign In or Register to comment.