Abstract
The interactions of glycylglycine (di-peptide of glycine) also known as 2-[(2-aminoacetyl)amino] acetic acid with cationic surfactants cetylpyridinium chloride (CPC) and cetylpyridinium bromide (CPB) as a function of temperature in aqueous medium has been studied by well-know permutation of volumetric, ultrasonic and conductometric techniques. These measurements have been used to evaluate some useful thermodynamic parameters viz. apparent molar volumes, phi(nu), partial molar volumes, phi(0)(nu), transfer volumes, phi(0)(v)(tr), partial molar expansibility, phi(0)(E), hydration number, n(H), apparent molal compressibility, phi(K), limiting partial molal adiabatic compressibility, phi(0)(K). The specific conductivity (kappa) was used to calculate the critical micellar concentration (cmc) and other physicochemical parameters of micellization of CPC/CPB with glycylglycine. The critical micelle concentration, cmc and limiting molar conductivity, Lambda(0)(m) of the two surfactant systems were determined by using the conductivity data at 298.15 K, 303.15 K, 308.15 K and 313.15 K. The acquired data have been discussed as per various interactions taking place in the ternary system of CPC/CPB, glycylglycine and water.