Need advice on dissolving Salicylic Acid

Hi, 
I had an experiment using Salicylic Acid (SA). I tried to dissolve SA using different solvent but it doesnt seem to dissolve perfectly. 

1. Water
I heat the water up to 70C. The salicylic acid indeed dissolve but when it cools down, it crystallized again.

2. Glycerin
I add 4g Glycerin in 0.2g SA. After that i put it in the hot bath. It does dissolve but there are some paricals that's still present. (I think it didnt dissolve completely ?)

3. Alcohol 90%
I add Alcohol into the SA. It seems to dissolve but afterwards, the SA started to stick on the side of beaker glass. So I dont think alcohol dissolve the SA.

4. Mineral oil
I add mineral oil into the SA. Put it in the hot bath. But it doesnt seems to dissolve. 

So how to actually dissolve SA ? and if for example, I want to make lotion or perhaps acne spot cream, can a "partially" dissolved SA be used ? For example using the Glycerin SA mixture into the lotion ?  

Thanks for the advice ! Very appreciated :) 

Comments

  • ozgirlozgirl Member, PCF student
    There are many posts about this topic on this forum. Just try using the search function.
  • There are quite a few posts on solubility of SA already, so depending on your preference, the solvent varies. 

    Normally for a 1% SA cream, i use Betaine. For 2%, i use Octyldodecanol with Betaine. 
  • Should have checked it before hand. Thank you !! 😁 @ozgirl @jemolian
  • Propylene glycol worked for me. I made a 5% solution dissolved in nothing but propylene glycol. 
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