Chelate surfactants were synthesized which having one or two hydrophobic long chained alkyl groups and hydrophilic EDTA-metal chelate ions, and their properties were investigated.
N- (1-carboxypentadecyl) ethylenediaminetriacetic acid (C-monotetradecyl EDTA) and N, N'-bis (1-carboxyundecyl) ethylenediaminediacetic acid (C, C'-didecyl FDTA) were used as the chelating agents and they were treated with salts of some transitional metals.
The formation of each metal chelate waas observed. It was shown from IR spectra, changes of color and from pH effects that the chelates prepared from C-alkyl EDTA and iron sulfate had octahedral chelating structure.
The chelate surfactants thus obtained showed good surface activities. Above all, the chelate surfactant from C, C'-didecyl EDTA and iron sulfate had a particularly superior dipersing power for pigments in coatings.