A NEW METHOD FOR THE DETERMINATION OF THE FIRST AND SECOND CMC IN CTAB SOLUTION BY RESONANCE RAYLEIGH SCATTERING TECHNOLOGY

ABSTRACT

A new light scattering technology is shown for study of the chemical character of a surfactant system. The resonance Rayleigh scattering (RRS) intensities of hexadecyltrimethylammonium bromide (CTAB) aqueous solution in a series of concentration were measured directly by a RRS technology without any probe. The first and second CMC of CTAB aqueous solution are obtained from the intensity of RRS vs concentration of CTAB curve, which are 8.9 × 10⁻⁴ and 2.0 × 10⁻² mol L⁻¹. These determination results are in correspondence with the results reported. Therefore, this method is very convenient, rapid and accurate and can be used as a new technology for the determination of CMC values of surfactants.

Keywords:

• Resonance Rayleigh scattering technology
• Critical micellization concentration
• Hexadecyltrimethylammonium bromide

ACKNOWLEDGMENTS

This project is supported by the National Natural Science Foundation of China. All the authors here express their deep thanks.