1960 年 80 巻 1 号 p. 99-102
It had been clarified that the solubilizing action of acid amides and the increased solubility of a solubilizate are due to complex formation. In order to analyze the complex formation reaction of acid amides and solubilizate as aid to the study of solubilizing agents, thermodynamic constants of interaction between a solubilizate and several of the solubilizing agents, such as nicotinamide and salicylamide, which had strong activity, were examined. In order to obtain such thermodynamic constants, it was necessary to know equilibrium constants at different temperatures and constants were measured at 10°, 25°, and 35°. It was found that the energy of complex formation was 1, 500-5, 000cal./mole, indicating that the reaction is exothermic. Free energy difference showed that such reaction took place easily.