THE EFFECT OF DIFFERENT MONOCARBOXYLIC ACIDS ON THE GELATION BEHAVIOROF CU ETHOXIDE

Cu ethoxide becomes soluble in methoxyethanol when formic, acetic, or acrylic acid is added. For the complete dissolution, the minimum molar ratio of an acid to Cu ethoxide is two for formic acid (HOFA), and on e for acetic (HOAC) or acrylic (HOAA) acid. The solutions of Cu ethoxi de with any amounts of formic acid are incapable of forming gels. Thos e with acetic or acrylic acid/Cu ratio of 1 are able to convert to gel s. For the range of the water concentration from 1.5 to 10 M, the gela tion time is strongly dependent on [H2O] for the solution with HOAC/Cu ratio of 1, while it is almost independent for the solution with HOAA . It is suggested that the differences in the behaviour of soluble Cu species derived from the three acids are attributed to different coord ination forms and the bonding strength between ligands and copper ions .