Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: pinkipod on April 04, 2006, 02:25:10 AM
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Hi everyone.
I have read all I could find regarding soap making and the discussions regarding NaOH and KOH (and some very interesting comments). However, I couldn't find anything about the difference the oil makes in soap making.
Compilations of expreimental data using combinations of NaOH or KOH with corn oil and olive oil show that olive oil & NaOH makes the best soap while corn oil and KOH makes the worst (If ever made)
I'm assuming that the structure of the long hydrophobic chains affect the outcome.
Can anyone elaborate on why one combination would make better soap?
Corn oil is 10% saturated fat, 20% monounsaturated fat, and 70% poly-unsaturated fat
Oilve oil is 10% saturated fat, 80% monounsaturated fat, and 10% polyunsaturated fat.
Thank you ~ ~
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i'm guessing the olive oil has a longer carbon chain. This longer carbon chain is mostly nonpolar, so it has better nonpolar penetration with grease and oils compared to other oils with shorter chains. A longer carbon chain will dig deep into the grease and hold better than shorter tails. Can anyone else verify?
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interesting....ddnnee
I was thinking along the lines of....
Perhaps the monounsaturated chains are harder to break than polyunsaturated fat..
So corn oil chains break into smaller pieces making it difficult to make solid soap...
(Does this make sense?)
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oh i didn't know. I that you were referring to the chemical properties. Physically, a more saturated tail would mean a more solid soap? I don't know whether olive or corn oil has a longer tail.
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In addition to lenght of the fatty acid chain, the saturation of the fatty acid chain also affects its melting point. The more saturated a chain is, the more solid its soap will be.