EFFECT OF PYRENE CHAIN END LABELING ON THE INTERACTION OF POLY(ETHYLENE OXIDE) WITH SODIUM DODECYL-SULFATE IN AQUEOUS-SOLUTION

The photobehavior of pyrene chain end labeled poly(ethylene oxide) (PEOPy) in aqueous solution is strongly modified by sodium dodecyl sulfate (SDS) addition. At low surfactant concentrations the excimer/monomer emission intensity ratio increases with SDS addition, a result explained in terms of PEOPy incorporation into aggregates comprising two or more end-labeled chains. The aggregation of the surfactant onto the end-labeled chains takes place at SDS concentrations considerably lower than those required to produce its micellization onto the unlabeled poly(ethylene oxide) chains. At higher surfactant concentrations, the excimer/monomer emission intensity ratio decreases as a consequence of dilution of the polymer molecules into an increasing number of micelles. © 1990, American Chemical Society. All rights reserved.