EFFECT OF DOUBLE-BOND ON THE SURFACE-PROPERTIES OF AQUEOUS-SOLUTIONS OF EICOSAPOLYENOIC ACIDS

Surface tensions of aqueous solution of eicosapolyenoic acids (EA) wit h 2 approximately 5 double bonds were measured by use of a Du Nouy ten siometer at pH 7.80 and 25-degrees-C, and the effects of double bond o n the surface properties of EA were investigated. The value of critica l micelle concentration of EA increased twofold with increasing number of double bonds. The free energy for the adsorption per double bond a t the air-water interface was estimated as 2.47 kj (double bond)-1, an d the negative value of free energy for the adsorption of EA molecule decreased with increasing number of double bonds.