Fluorescence Probe and Pulsed Field Gradient NMR Study of Aqueous Solutions of Poly(ethylene oxide)−Poly(propylene oxide)−Poly(ethylene oxide) Block Copolymer F88

Rongbiao Wang, Helmut Knoll, Frank Rittig, Jörg Kärger

Langmuir · 2001 · 19 citations · 19 references

Concepts

Abstract

In aqueous solutions of the triblock copolymer F88 (EO 96 PO 39 EO 96 ) micelle formation has been studied by means of dual fluorescence of the probe molecule 1,3-bis(1-pyrene)propane monitoring viscosity changes in its microenvironment. Mobility changes of the polymer molecules on micellization were followed by means of pulsed field gradient (PFG) NMR. These results complement a recent detailed study of cis−trans isomerization of azo dyes as “kinetic probes” for structure formation in aqueous solutions of F88 ( Langmuir 2001, 17, 2907). Differences of the critical micellization temperatures determined by various methods, and in H 2 O and D 2 O as solvents, are discussed. Our results reflect the particular large content of polye(ethylene oxide) in F88 (80%) compared to other triblock copolymers of this type.

References

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