Home Cosmetic Science Talk Formulating MEA, DEA & TEA

  • MEA, DEA & TEA

    Posted by chemist77 on July 26, 2015 at 7:38 am

    The other day someone asked me the reason as to why I just use TEA & why not MEA instead for my creams and lotions. Suddenly it struck me that yeah why not, but are there any downsides if I replace TEA with MEA after proper calculations. And why most emulsion systems in personal care prefer the tertiary amine instead of MEA???

    bobzchemist replied 8 years, 8 months ago 4 Members · 4 Replies
  • 4 Replies
  • david

    Member
    July 27, 2015 at 10:01 pm

    not really an answer but TEA is less reactive than MEA and DEA can form nitrosamines…

  • chemicalmatt

    Member
    July 27, 2015 at 10:12 pm

    If you are only using it as an alkali neutralizer for carbomers, acrylate thickeners, etc., then any alkali other than DEA is OK (for the nitrosamine precursor reason David stated.) If you are saponifying fatty acids, though, it will make a large difference in the texture outcome of , say, a shaving cream. 

  • chemist77

    Member
    July 28, 2015 at 1:01 am

    Thank you so much @David & @chemicalmatt

  • bobzchemist

    Member
    July 28, 2015 at 2:09 pm

    Great point, Matt.

    To use this as a teachable cosmetic lab moment, take a basic o/w lotion that relies on saponifying a fatty acid (typically stearic) for emulsification, and make 4 batches, using TEA, NaOH, KOH, and AMP as saponifying agents, holding all other components the same (qs water as needed). (Extra credit if you can find other saponifying agents to try - I know of at least three more)
    Evaluate the texture, skin feel and viscosity of each cream. Maybe even do some basic stability testing. Give a sample of each to other people to try and get their impressions.

Log in to reply.