Electrochemical control of solubilization using a ferrocene-modified nonionic surfactant

Citation
T. Takei et al., Electrochemical control of solubilization using a ferrocene-modified nonionic surfactant, COLL SURF A, 183, 2001, pp. 757-765
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
ISSN journal
0927-7757 → ACNP
Volume
183
Year of publication
2001
Pages
757 - 765
Database
ISI
SICI code
0927-7757(20010715)183:<757:ECOSUA>2.0.ZU;2-O
Abstract
An investigation was conducted on the control of solubilization making use pf changes in the surface properties caused by the electrochemical redox re action of 11-ferrocenylundecyl polyoxyethylene ether (FPEG), a ferrocene-mo dified nonionic surfactant, in aqueous solutions. Examinations through surf ace tension measurement of the effect of the redox reaction of the ferrocen yl group on the critical micelle concentration (cmc) of FPEG showed that th e oxidation produces an increase in the cmc from 6 x 10(-6) to 5 x 10(-5) m ol l(-1) and the re-reduction causes the cmc to decrease from 5 x 10(-5) to 9 x 10(-6) mol l(-1). The effect of the redox reaction of the ferrocenyl g roup was then examined on the solubilization equilibrium constant, K, for s olubilization of benzene, ethylbenzene and 2-phenylethylalcohol in FPEG mic elles. The equilibrium constant was found for all solubilizates to decrease when the ferrocenyl group is oxidized and increase again if the group is r e-reduced, indicating that oxidation of the ferrocenyl group releases porti ons of the solubilizate from the micelles into the bulk and the re-reductio n gives rise to re-solubilization of the released solubilizate. (C) 2001 Pu blished by Elsevier Science B.V. All rights reserved.