ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 37, Number 10
JKCSEZ 37(10)
August 20, 1993 

In the presence of SDS(sodium dodecyl sulfate), effect of Ca2+on the interaction of NP-40EO[nonylphenol-(ethylene oxide)40] with iodine in aqueous solution were investigated by UV-visible spectrophotometer. In the presence of SDS, the intensity of interaction peaks were decreased and markedly increased by the addition of Ca2+. Decrease of interaction peaks is caused by decrease of EO number to be interact with iodine per unit surface area of mixed micelle to the insertion of SDS and increase is attributed to the compactness of micelle in the presence of Ca2+. These phenomena may be explained by the fact that the linear EO (ethylene oxide) chains, to be free in aqueous solution, could form a pseudo-crown ether structures of forming with Ca2+ion.