Ask A Scientist Materials Science Archive

  
name         Janine
status       educator
grade        9-12
location     TX

Question -   In a common scented wax candle, is the fragrance bound to
the paraffin or simply incorporated into the candle as discrete droplets?
If bound to the paraffin, is it by hydrogen bonding? I realize there are
many scent and candle types, but I would appreciate any simple example.
This question arose when I received an electronic unit that allows the
scent to be released from an unlit glass-encased candle.
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   Electrically activated scented units have low--power heaters that cause
the fragrant oil to evaporate. In candles, the heat of the candle burning
provides the heat. In both cases there is more "technology" than you would
expect at first. The scented oil may/may not be sufficiently soluble in
the wax. The scent must be non-toxic, although some people are allergic to
the chemicals. The scent must not decompose in the flame -- at least it
must not produce smoke,soot, or toxic combustion products.
  The paraffin does not hydrogen bond to any extent -- remember the
paraffin is basically a high molecular weight hydrocarbon. Most of the
scenting chemicals have a powerful odor so it does not require much
solubility in the wax to be effective.

Vince Calder
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