Fat models frequently use input parameters that are defined at environmental conditions. In a recently developed gas-liquid chromatography method (GC-VAP), vapor pressures, heats of vaporization, and heat capacity differences (gas-liquid) of fatty acid esters are determined over a large temperature range that includes environmental temperatures. This method also allows an accurate determination of the normal boiling point temperature of a substance. Literature values of vapor pressure, boiling point temperature, and heat of vaporization at 298.15 K for the chosen esters are all in excellent agreement with those determined with the developed method. Correlations between carbon number and heat of vaporization are high. JAOCS 74, 309-315 (1997).
KEY WORDS:Fatty acid esters, heat capacity, heat of vaporization, QSAR, solubility parameter, vapor pressure.
METHODS
Physical-Chemical ModelDetailed descriptions of the method used can be found elsewhere (1,5,6). In short, the Kováts retention indices of the un-