SEGREGATION IN AQUEOUS SYSTEMS OF A POLYELECTROLYTE AND AN IONIC SURFACTANT

Citation
K. Thalberg et B. Lindman, SEGREGATION IN AQUEOUS SYSTEMS OF A POLYELECTROLYTE AND AN IONIC SURFACTANT, Colloids and surfaces. A, Physicochemical and engineering aspects, 76, 1993, pp. 283-288
Citations number
15
Categorie Soggetti
Chemistry Physical
ISSN journal
09277757
Volume
76
Year of publication
1993
Pages
283 - 288
Database
ISI
SICI code
0927-7757(1993)76:<283:SIASOA>2.0.ZU;2-X
Abstract
Phase diagram studies have been carried out for systems of a polyelect rolyte and an oppositely charged surfactant in the presence of high co ncentrations of salt, and for systems of a polyelectrolyte and a surfa ctant with the same charge. All the systems studied display phase sepa ration of the segregative type. In the former case, phase separation i s facilitated by increasing either the alkyl chain length of the surfa ctant or the molecular weight of the polyelectrolyte. In the latter ca se, phase separation takes place in the absence of salt but is markedl y enhanced by salt addition. An increased surfactant chain length and an increased polyelectrolyte molecular weight facilitates phase separa tion also in this case. For both types of system the tie lines are mar kedly skewed, an observation which cannot be explained by Flory-Huggin gs-type models.