Home Cosmetic Science Talk Formulating Emulfiying 20% Icaridin in water

  • Emulfiying 20% Icaridin in water

    Posted by sammos on August 2, 2014 at 1:51 pm

    Hi There,

    another one for you guys… best way to disperse 20% Icaridin http://en.wikipedia.org/wiki/Icaridin in water (ideally also 1% essential oil).
    PEG-40 does a fairly good job, but causes 2 layers to form over time and does not disperse consistently throughout batch.
    Polysorbate-20 looks to be an improvement.
    Sugarmulse (recommended as a natural alternative to PEG on here) was the worst of the lot.
    I feel like I am close with Polysorbate-20 but is still layering out.
    We want the end result to be as thin as possible to make it easily sprayable, ideally natural, ideally liquid at room temperature to making mfr process as simple as possible.
    Thanks for lending your brains!
    Kind regards,
    sammos replied 9 years, 11 months ago 3 Members · 7 Replies
  • 7 Replies
  • chemicalmatt

    August 4, 2014 at 11:46 am

    Sammos, if opacity is not a factor, I’ve been getting great results with Imulsifi, the polymeric stabilizer/emulsifier from FIberstar.  Its derived from orange pulp and doesn’t build viscosity until you get above 2% or so.  It should hold that oil load and spray sufficiently,  Icaridin might require a mid-HLB co-surfactant like PEG-40 HCO along with the Imusifi. 

  • sammos

    August 5, 2014 at 2:55 am

    Hi Matt,

    opacity is obligatory with this one i think!
    PEG-40 is not too far off, we get a more opaque milky layer under a less opaque one. SO it is close.
    PS-60 was the next best but separated overnight.
    Have dropped Fiberstar a line to see if I can get a sample.
  • sammos

    August 5, 2014 at 3:48 pm

    PEG-40 is so close, I wonder if I just need a co-surfactant… as long as it does not increase viscoscity or allows me to use less PEG. Any ideas?

  • ozgirl

    August 6, 2014 at 1:58 am

    Can you add some ethanol or other water soluble solvent to help solubilize your active?

  • sammos

    August 6, 2014 at 3:21 pm

    I am loathed to Ozgirl as it will increase expense and currently we quote a ‘alcohol free formula’ as it is an insect repellent I don’t want too much volatility.

    I am open minded to it though, I stock IPA do you think that would work and what concentration would you propose?
  • ozgirl

    August 6, 2014 at 7:54 pm

    You could try a glycol ether solvent such as Dowanol DPM (INCI: PPG-2 Methyl Ether) if you want to stay away from alcohol. I have seen this used in an alcohol free perfume formulation with PEG-40 HCO to help solubilise the fragrance. From memory it was used at about 5%.


  • sammos

    August 7, 2014 at 4:15 pm

    Brilliant, I think i have some Dowanol - I will give it a try at say 5 and 10% (looks like that would cost me very little per bottle at those levels!)


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