fulltext.study @t Gmail

Photophysical study on aggregation of carboxylic perfluoropolyether derivatives in water: Time resolved fluorescence quenching measurements in the temperature range 297–333 K

Paper ID Volume ID Publish Year Pages File Format Full-Text
28863 44099 2007 5 PDF Available
Title
Photophysical study on aggregation of carboxylic perfluoropolyether derivatives in water: Time resolved fluorescence quenching measurements in the temperature range 297–333 K
Abstract

Aqueous micellar solutions of fluorinated surfactants Cl(C3F6O)2CF2COOX, X = NH4+ or Na+, have been examined in the temperature range 297–333 K by the time resolved fluorescence quenching technique, using cationic pyrene derivative as a luminophore and methylviologen cation as a quencher. Based on the model proposed by Infelta and Tachiya we have determined aggregation numbers, N, and rate constants of intramicellar fluorescence quenching, kqm, and of the quencher exit from micelles, k−. The observed dependencies of N as a function of temperature are compared with those reported from small angle neutron scattering studies [C.M.C. Gambi, R. Giordano, A. Chittofrati, P. Pieri, P. Baglioni, J. Texeira, J. Phys. Chem. A 107 (2003) 11558–11564; C.M.C. Gambi, R. Giordano, A. Chittofrati, P. Pieri, P.Baglioni, J. Texeira, J. Phys. Chem. B 109 (2005) 8592–8598]. The kqm and k− data, and the respective activation energies, are discussed in terms of micellar size, packing of surfactant molecules and charge density at the interface, depending on surfactant concentration and the kind of counterion.

Keywords
Perfluoropolyether surfactants; Micelles; Fluorescence quenching; Kinetics; Aggregation number
First Page Preview
Photophysical study on aggregation of carboxylic perfluoropolyether derivatives in water: Time resolved fluorescence quenching measurements in the temperature range 297–333 K
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Journal of Photochemistry and Photobiology A: Chemistry - Volume 191, Issue 1, 7 September 2007, Pages 1–5
Authors
, , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us