Determination of liquid–gas partition coefficients of BuA and MMA by headspace-gas chromatography utilizing the phase ratio variation method

The phase variation method is described and applied in order to determine liquid/gas partition coefficients of monomers in aqueous solutions as well as the effect of the presence of one monomer to the partition coefficient of the other. The method is based on the relationship between reciprocal peak area and the phase ratio in the vial containing the sample solution. It involves regression analysis of headspace gas chromatography measurements of a number of sample vials with a variation of phase ratios. The method is applied in the case of the monomers butyl acrylate and methyl methacrylate. Experimental data for the partition coefficient of the two acrylates are modeled with the Statistical-Associating-Fluid Theory (SAFT).