Binding of photosurfactant (4-butyl-azobenzene-4 ' oxyethyltrimethylammonium bromide) to polyelectrolyte

The binding of a photosurfactant, 4-butyl-azobenzene-4'-oxyethyltrimethyl a mmonium bromide (BZTABr), to a linear polymer, sodium poly(2-acrylamide-2-m ethylpropane sulfonate) (PAMPS), has been studied by using a surfactant sel ective electrode. The photosurfactant undergoes a trans-cis transition on U V/vis irradiation. The binding behavior changes by varying the composition of the trans and cis forms in the solution. The ideal mixing-ideal cooperat ive binding model we had proposed previously for the binding of binary surf actants was applied to successfully predict the binding isotherms and the c ritical aggregation concentrations of the present systems. The binding of a trans-cis mixture of BZTABr to a polymer is analogous to the ideal mixed m icelle formation. A sort of synergetic effect was found in the binding proc ess. (C) 1999 Academic Press.