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  • Solubilisation conundrum

    Posted by Tendo on February 13, 2020 at 9:03 pm

    Hello, newbie here! 

    I am attempting (not very successfully I might add) with solubilising oils into a water solution for a hair milk I’m developing. I live in Kampala, Uganda so obtaining newer/ better ingredients is nigh near impossible or it costs both kidneys and an arm! 
    Had a chemist suggest that I use monopropylene glycol and isopropyl myristate but I’m unsure if this will work as I’ve never used MPG before. Please have a look-see and any suggestions/ recommendations would be greatly appreciated
    formula is: 
    water 77.18%
    Caprylic/capric triglycerides 7%
    Symbiosolv clear 4%
    Isopropyl myristate 4%
    Argania Spinosa 3%
    Monopropylene glycol 2%
    Aloe phytelene 1%
    Phenoxyethanol 1%
    Majoram essential oil 0.6%
    Ginger 0.15%
    Lime essential oil 0.07%
    I am hoping for a milky solution and not necessarily a clear one at the end. 
    Thank you! 

    Tendo replied 4 years, 8 months ago 6 Members · 11 Replies
  • 11 Replies
  • belassi

    Member
    February 14, 2020 at 1:49 am

    What problems have you experienced? You understand, I can’t just look at your LOI and tell you what to do. I would have to make it myself and see what happened. The preservative is not good against mould but it could be that the EOs would be sufficient. I think the 0.6% EO is way too much. Maybe 0.3% tops?

  • Tendo

    Member
    February 14, 2020 at 8:00 am

    The solution isn’t homogeneous, separates out into a thick milky layer settling on the top and a lighter one at the bottom. I’m hoping to end up with a uniform solution not one that requires shaking before use. Thanks for the suggestion on the majoram, I’ll try it with the reduced amount. Any suggestions for preserving against mold? 
    Thank you for the response! 

  • Tendo

    Member
    February 14, 2020 at 10:20 am

  • chemicalmatt

    Member
    February 14, 2020 at 4:29 pm

    Tendo, you should be able to obtain Polysorbate 80 (FG - food grade) In Kampala from a food ingredient supply house.  Try that. Otherwise lecithin may be a long shot here.  Good luck!

  • Tendo

    Member
    February 14, 2020 at 8:04 pm

    Thanks for the suggestion, but that is what I used at the beginning and had the same problem. Interestingly the same formula with locally sourced avocado oil produced the milky solution I’m gunning for. So I’m not quite sure why it is not playing nicely with lighter oils. I think I am going to try and formulate a very thin emulsion that can be sprayed. 

  • Bill_Toge

    Member
    February 14, 2020 at 10:17 pm
    the fundamental problem is that the two phases in your product have different densities, and your product is a Newtonian fluid (has no viscosity at zero shear), which causes them to separate over time
    your best bet is adding a rheology modifier to the water phase, e.g. a carbomer of some kind, which renders your product pseudoplastic (i.e. immobile at zero shear) and physically prevents the phases from separating
  • Tendo

    Member
    February 15, 2020 at 8:44 am

    Thanks! Experimentation coming up with carbomer 940 as that is what I can easily obtain. 

  • Tendo

    Member
    February 23, 2020 at 9:02 am

    @Bill_Toge thanks again for the direction. So I made a milky liquid finally with the carbomer and have a stable product that hasn’t precipitated out of solution or separated. Ph is holding at 6.8. I used a 10% NaOH solution to neutralise. Given that this is intended as a leave on spray, is the NaOH in the formula detrimental to hair in any way? 

  • Gunther

    Member
    February 23, 2020 at 11:33 pm

    IMO too little emulsifier and too much oils (Caprylic/capric triglycerides and Isopropyl myristate).

    If it’s intended for spray use, carbopol will thicken it too much so it won’t come out as a fine mist out of the spray nozzle.

  • jemolian

    Member
    February 24, 2020 at 9:28 am

    You can look into emulsifier blends that can make sprays. One of the common one would be Glyceryl Stearate (and) PEG-100 Stearate, it is produced by companies so it has quite a few trade names such as Arlacel 165 or Simulsol 165.

  • Tendo

    Member
    February 25, 2020 at 10:08 am

    thank you both for the suggestions, will look for those emulsifiers

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