형광의 Depolarization을 이용한 Dodecyl Pyridinium Chloride 수용액의 제 2CMC에 관한 연구

Abstract

The depolarization of the fluorescence emitted from a dye solubilized in the micelle was measured ever a wide concentration range of Dodecyl Pynidinicm Chloride (DPC). The polarization of the fluorescence showed an abrupt increase at the 1st CMC (17mM) and an abrupt decrease at about 43mM of DPC, the latter agrees very closely with the 2nd CMC revealed by conductivity and viscosity measurements. This phenomenon implies that there is a certain change in the micelle structure at the 2nd CMC. The micellar size was calculated from the fluoreseence depolarization data using Perrirn's equation. The results showed that; the micellar volume of DPC abruptly increases at 1st CMC and reaches a constant value (about 9200ml/gram-micelle) and than keep up the value with the increase in the concentration of DPC, and the micellar volume of DPC decreases abruptly at the 2nd CMC and again remains at another constant value above the 2nd CMC.