Abstract
As a basic study for drycleaning, the effect of surfactant (Aerosol OT) concentration on the adhesion of spherical particles of hydrated iron (III) oxide (Fe2O3·H2O) has been investigated.
The amounts of adhesion to staple fibers of polyester, nylon-6 and cupra rayon were determined in n-hexane, n-heptane, n-undecane, tetrachloroethylene and ethyl alcohol in the presence of the surfactant at dilute concentration, in an incubator at 20°C after 48 h of weak mechanical oscillation.
The amounts of adhesion decreased with the concentration of the surfactant in the solvents except ethyl alcohol; critical concentrations for the depletion of adhered iron oxide were observed at dilute concentrations characteristic to the solvent species.
These observations led a conclusion that the critical amounts of the surfactant necessary for the dispersion of 1 g of the iron oxide were 3.3×10-4 mol in the petroleum solvents and 2.0×10-4 mol in tetrachloroethylene, respectively.
In ethyl alcohol, the amount of adhesion was very small as compared with those in the nonpolar solvents and hence no effect of the surfactant was observed.
