Anhydrous Cream sweats

Anca_Formulator

Hi, 

What is happening with this anhydrous cream?  

The formula contains the following: Babassu 29 %, Mango Butter 15%, Murumuru 15%, 10% Myrica wax, 10% Camellia Oil, 10% Hemisqualane, 3% Lauryl Laurate, and 0.5% Lecithin, the rest is heat sensitive oil based extracts (not yet incorporated in this base). The pink cream has 0.10% mica.

Method: I melted all of the above slowly and stirred during melting, then took it off the heat and split it to experiment with. 

# 1 (the yellow one in beaker) was left on the table, without further stirring. First two photos show what it looked like the next day.

I thought that cooling it at RT would just result in graininess, not separation or syneresis. 

# 3 (the pink) was placed in the fridge and stirred briefly roughly every 15 min until trace. 
At trace, I whipped it and placed one jar in the fridge for an additional 45 min. For about a week the top looked smooth. Then, Picture #3 shows what it looked like after a week. 

I left one jar at RT (picture #4) after whipping. The top was smooth for a week, then it looked quite sweaty (like #3), but then reabsorbed when left with lid open.

Why are the oils being expelled from the butters? Is this syneresis? The butters also look like they barely hang together. Is the oil to butter ratio off somehow? I made 10 versions of this formula with tweaks, and it happens every time. 

). 

Please help! Thank you.

ozgirl

What temperature is it where you are?

The Babassu Oil has a melting point right around room temperature (24C / 76F) so this probably causing some of your issues.

You could try increasing your butter and wax to try and raise the melting point of the product.

Anca_Formulator

Thank you so much. That makes sense. It's around 72 here, but the temp can fluctuate to around 76. I'll give that a try. 

Graillotion

Just guessing...but if Hemisqualane is anything like squalane....that typically causes that issue.

Try making it once without Hemisqualane...guessing issue will be Gone.

When I read the title....I said to myself....bet there is squalane in formula.

Believe the technical term is: syneresis.

Anca_Formulator

Graillotion said:

Just guessing...but if Hemisqualane is anything like squalane....that typically causes that issue.

Try making it once without Hemisqualane...guessing issue will be Gone.

When I read the title....I said to myself....bet there is squalane in formula.

Believe the technical term is: syneresis.

Thank you so much for your suggestion. I will give that a try. But why does squalane sweat?

Anca_Formulator

Anca_Formulator said:

Graillotion said:

When I read the title....I said to myself....bet there is squalane in formula.

Believe the technical term is: syneresis.

Hemi-squalane is supposed to be a non polar C15, so technically it shouldn't cause syneresis when it's mixed with other non-polar oils. Why does squalane cause syneresis (it's also technically non-polar)?

Graillotion

Anca_Formulator said:

Anca_Formulator said:

Graillotion said:

When I read the title....I said to myself....bet there is squalane in formula.

Believe the technical term is: syneresis.

Hemi-squalane is supposed to be a non polar C15, so technically it shouldn't cause syneresis when it's mixed with other non-polar oils. Why does squalane cause syneresis (it's also technically non-polar)?

I am not a chemist, so I will use my laymen terms as I understand things.  Squalane is for all intents and purposes...basically a hydrocarbon.  Therefore when trying to  emulsify it, it behaves much like the silicones.  So imagine in this case...if you added 10% cyclomethicone or dimethicone...would that pose any issues?

One of the things I use to avoid these issues...are crosslinked polymers, which tend to alleviate these concerns....but I never use anything remotely close to 10% of this type ingredient.

Hopefully without doing a disservice to Pharma, I will paste below...a slightly out of context response he gave me, regarding weeping I can get a little of...on a very difficult mosquito formula I have been working on for the last couple of years...and using a crosspolymer to help with weeping:

Your crosspolymer does the same as high cP dimethicone and more .
The statement is correct and is so for all silicone crosspolymers. It's a bit like vaseline which is basically liquid paraffin embedded in a sponge-like structure built by a wax-like solid composed of huge, branched hydrocarbons... macrostructure-wise fairly similar to synthetic silicone crosspolymers.
Your has a unique feature of being highly hydrophobic alkyl (= C30-45 and cetearyl) chains all over it. It interacts better with fats and oils than, say, vinyl cross-linked polymers. However, I'm not sure if it would work specifically with vanillin given that this molecule is not that hydrophobic and it might not interact well enough with alkyl modified versions especially if there's a bunch of ingredients around it which do interact better. A PEG, PPG, or polyglyceryl cross-linked dimethicones might work better. However, it will form that sponge-like structure which, in effect, is similar to adding a wax or high-melting fat: it gels the oil phase and hence, a more stable product under others due to greatly reduced Ostwald ripening, coalescence, and creaming.

Again...slightly out of context.

Anca_Formulator

@Graillotion: Thank you so much for taking the time to explain this. Some of it goes over my head as I am not a chemist either, but some of it makes sense ;-)

kivangel

@Anca_Formulator I know this is an older post, but in case you still need this... I believe levels of butters & oil with low melting temperature are too high. Mango, babassu & murmuru all have relatively low melting points, so they can partially melt depending on ambient temperature & cause some of the issues you are seeing. Maybe also increase lecithin slightly, for better consistency. And cool finished formula quickly. Lastly (unrelated to the issue you are seeing) some antioxidant like tocopherol is needed to prevent oil rancidity.

Shams

@Anca_Formulator Agree with @kivangel. You are using way too much of butters. Butters should compose no more than 10% of your formula, if you want a product that will be stable at different temperatures.
You can try thickening your formula with something like : hydrogenated vegetable oil or may be beeswax or any other high melting point wax. Never rely on butters for consistency as they have low melting point

Anca_Formulator

@kivangel
Thank you so much. You are absolutely right! I will try raising the melting point with a fatty alcohol, acid or ester. 

P.S. (there is tocopherol, I forgot to mention)

Anca_Formulator

@shams ; Thank you. Indeed, those butters cannot keep this formula together. I don't like the texture imparted by wax for this formula, but a hydrogenated vegetable oil might be interesting. I'll give it a go. 

Abdullah

What are waxes doing here? 

If they are to keep everything together and increase viscosity then you can use EGDS or GMS instead. 
They have better skin feel and are better suited for these functions.

Anca_Formulator

Abdullah said:

What are waxes doing here? 

Thank you do much! Yes, they are only there to hold things together. I love your GMS suggestion, I will try it. I am not familiar with EGDS, aka glycol distearate? I'm curious about it so I'll look into it. Thanks again!

Abdullah

Yes it is Glycol distearate