Excimer-monomer emission in alkylbenzenesulfonate dispersions

Effect of the surfactant structure on aggregation

M. Aoudia, W. H. Wade, M. A J Rodgers

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Aqueous micellar dispersions of several alkylbenzenesulfonates (xφC12 and xφC16) where x = 1, 2, 3 ... and indicates the position of the phenyl group (φ) along the alkyl chain were prepared and examined for fluorescence emission from the benzene residues. Quantitative measurements of the intensities of the monomer and excimer contributions to the fluorescence spectrum as a function of surfactant concentration, when normalized to unit absorbance showed two linear regimes. The break point between the two occurred at a critical micellar concentration (CMC) defined by conductivity and surface tension measurements. Evidence for premicellar aggregates, at surfactant concentrations well below the CMC, was demonstrated. The CMC was related to a transition in the range of aggregation size distribution. The aggregation number was shown to depend on the surfactant structure. For a series of isomers, the aggregation number decreases when the sulfonate benzene group is moved from one end to the center of the aliphatic alkyl chain. This tendency was related to the (hydrophobic/lipophilic) balance of the surfactant.

Original languageEnglish
Pages (from-to)493-501
Number of pages9
JournalJournal of Colloid and Interface Science
Volume145
Issue number2
DOIs
Publication statusPublished - 1991

Fingerprint

excimers
Dispersions
Surface-Active Agents
Surface active agents
Agglomeration
monomers
Monomers
surfactants
Benzene
Fluorescence
benzene
fluorescence
Isomers
Surface tension
sulfonates
interfacial tension
tendencies
isomers
conductivity

ASJC Scopus subject areas

  • Colloid and Surface Chemistry
  • Physical and Theoretical Chemistry
  • Surfaces and Interfaces

Cite this

Excimer-monomer emission in alkylbenzenesulfonate dispersions : Effect of the surfactant structure on aggregation. / Aoudia, M.; Wade, W. H.; Rodgers, M. A J.

In: Journal of Colloid and Interface Science, Vol. 145, No. 2, 1991, p. 493-501.

Research output: Contribution to journalArticle

@article{615d0e3c3a8f4cd3bd6c1ceaabad7cba,
title = "Excimer-monomer emission in alkylbenzenesulfonate dispersions: Effect of the surfactant structure on aggregation",
abstract = "Aqueous micellar dispersions of several alkylbenzenesulfonates (xφC12 and xφC16) where x = 1, 2, 3 ... and indicates the position of the phenyl group (φ) along the alkyl chain were prepared and examined for fluorescence emission from the benzene residues. Quantitative measurements of the intensities of the monomer and excimer contributions to the fluorescence spectrum as a function of surfactant concentration, when normalized to unit absorbance showed two linear regimes. The break point between the two occurred at a critical micellar concentration (CMC) defined by conductivity and surface tension measurements. Evidence for premicellar aggregates, at surfactant concentrations well below the CMC, was demonstrated. The CMC was related to a transition in the range of aggregation size distribution. The aggregation number was shown to depend on the surfactant structure. For a series of isomers, the aggregation number decreases when the sulfonate benzene group is moved from one end to the center of the aliphatic alkyl chain. This tendency was related to the (hydrophobic/lipophilic) balance of the surfactant.",
author = "M. Aoudia and Wade, {W. H.} and Rodgers, {M. A J}",
year = "1991",
doi = "10.1016/0021-9797(91)90380-Q",
language = "English",
volume = "145",
pages = "493--501",
journal = "Journal of Colloid and Interface Science",
issn = "0021-9797",
publisher = "Academic Press Inc.",
number = "2",

}

TY - JOUR

T1 - Excimer-monomer emission in alkylbenzenesulfonate dispersions

T2 - Effect of the surfactant structure on aggregation

AU - Aoudia, M.

AU - Wade, W. H.

AU - Rodgers, M. A J

PY - 1991

Y1 - 1991

N2 - Aqueous micellar dispersions of several alkylbenzenesulfonates (xφC12 and xφC16) where x = 1, 2, 3 ... and indicates the position of the phenyl group (φ) along the alkyl chain were prepared and examined for fluorescence emission from the benzene residues. Quantitative measurements of the intensities of the monomer and excimer contributions to the fluorescence spectrum as a function of surfactant concentration, when normalized to unit absorbance showed two linear regimes. The break point between the two occurred at a critical micellar concentration (CMC) defined by conductivity and surface tension measurements. Evidence for premicellar aggregates, at surfactant concentrations well below the CMC, was demonstrated. The CMC was related to a transition in the range of aggregation size distribution. The aggregation number was shown to depend on the surfactant structure. For a series of isomers, the aggregation number decreases when the sulfonate benzene group is moved from one end to the center of the aliphatic alkyl chain. This tendency was related to the (hydrophobic/lipophilic) balance of the surfactant.

AB - Aqueous micellar dispersions of several alkylbenzenesulfonates (xφC12 and xφC16) where x = 1, 2, 3 ... and indicates the position of the phenyl group (φ) along the alkyl chain were prepared and examined for fluorescence emission from the benzene residues. Quantitative measurements of the intensities of the monomer and excimer contributions to the fluorescence spectrum as a function of surfactant concentration, when normalized to unit absorbance showed two linear regimes. The break point between the two occurred at a critical micellar concentration (CMC) defined by conductivity and surface tension measurements. Evidence for premicellar aggregates, at surfactant concentrations well below the CMC, was demonstrated. The CMC was related to a transition in the range of aggregation size distribution. The aggregation number was shown to depend on the surfactant structure. For a series of isomers, the aggregation number decreases when the sulfonate benzene group is moved from one end to the center of the aliphatic alkyl chain. This tendency was related to the (hydrophobic/lipophilic) balance of the surfactant.

UR - http://www.scopus.com/inward/record.url?scp=0026219356&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0026219356&partnerID=8YFLogxK

U2 - 10.1016/0021-9797(91)90380-Q

DO - 10.1016/0021-9797(91)90380-Q

M3 - Article

VL - 145

SP - 493

EP - 501

JO - Journal of Colloid and Interface Science

JF - Journal of Colloid and Interface Science

SN - 0021-9797

IS - 2

ER -