2004 Volume 53 Issue 4 Pages 167-175
The mechanisms for removal of synthetic sebum constituents squalene, cholesterol, triolein and oleic acid from polyester (PET) fabric substrate in an aqueous solution of sodium dodecyl sulfate (SDS) were studied by applying a pseudo-phase retention equation to the migration of a soil in a liquid chromatography column in which the fabric serves as the stationary phase and an aqueous micellar solution of SDS serves as the mobile phase. The retention volume of the four fatty soils on PET fabric was measured as a function of the SDS concentration in the mobile phase. The changes in standard free energy of soil transfer from water onto the fabric substrate (-ΔG°sw), from water into micelles (-ΔG°mw) and from fabric substrate into the micelles (-ΔG°ms) were calculated from the partition coefficient data determined chromatographically at various concentrations of micellar mobile phases. The -ΔG°sw for the re-deposition of fatty soil onto the PET substrate increased in the following order: cholesterol < oleic acid < squalene v triolein. The -ΔG°mw for solubilization of the soil from water (non-micellar solution) into SDS micelles increased in the following order: oleic acid < cholesterol v squalene v triolein. The -ΔG°ms for removal of the soil from the PET substrate into SDS micelles decreased in the following order: cholesterol > squalene > triolein. These thermodynamic parameters suggest that removal of fatty soils from PET fabric is dependent on the tendencies of the soils to redeposit onto the fabric and to solubilize into SDS micelles.
