I. Katime et al., STRUCTURE AND THERMODYNAMICS OF POLYSTYRENE-BLOCK-POLY(ETHYLENE PROPENE) MICELLES IN SELECTIVE SOLVENTS, Macromolecular symposia, 84, 1994, pp. 255-265
The concentration and temperature dependencies of micelle formation by
a polystyrene-block-poly(ethylene/propene) copolymer in several keton
es (2-butanone, 3-pentanone, 4-methyl-2-pentanone, 4-heptanone, 5-meth
yl-2-hexanone and 5-methyl-3-heptanone) were studied by static and dyn
amic light scattering, viscometry and size exclusion chromatography. N
o micelles were detected in solutions of 5-methyl-3-heptanone. The sta
ndard Gibbs energy, DELTSAG-degrees, the standard enthalpy, DELTAH-deg
rees, and the standard entropy, DELTAG-degrees, of micellization were
estimated. The values of DELTAG-degrees and DELTAH-degrees were negati
ve for all ketones studied and depended on the polar character of the
ketone. The micelles showed larger association numbers and densities i
ndependent of the ketone. Micelle dimensions hardly depended on the ke
tone.