1982 Volume 31 Issue 1 Pages 47-51
Diethylenetriaminepentaacetic acid (DTPA) dianhydride was treated with four long chained alcohols (dodecyl, tetradecyl, hexadecyl, and octadecyl alcohols) to form four DTPA-monoalkyl esters (C12-, C14-, C16-, and C18-esters) being complexane-type surface active ligands. The equivalent reactions between the complexanes and several metal ions gave the corresponding (1 : 1) metal chelates in good yield (84% in average). All metal chelates prepared were easily soluble in water.
The surface and interfacial tensions of the aqueous chelate solutions increased with an increase in alkyl chain length of the chelates, ranging from 23 to 47 dyn/cm and from 0 to 8.6 dyn/cm, respectively.
The emulsifying (water/kerosene) and dispersing [TiO2/toluene-butanol (1 : 1)] powers, however, increased with an increase in the alkyl chain length.
The emulsifying and dispersing powers of these chelates synthesized in this study were superior to those of the chelates which had been so far reported by authors.