Eur. Phys. J. B 1, 77-86 (1998)
https://doi.org/10.1007/s100510050154

Structural properties of charged diblock copolymer solutions

¹ Service de Physique de l'Etat Condensé, C.E.A. Saclay, 91191 Gif-sur-Yvette Cedex, France
² Service de Chimie Moléculaire, C.E.A. Saclay, 91191 Gif-sur-Yvette Cedex, France
³ Department of Chemistry, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
⁴ Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA
⁵ Laboratoire Léon Brillouin, C.E.A. Saclay, 91191 Gif-sur-Yvette Cedex, France

Corresponding author: ^a pguenoun@cea.fr

Received: 19 June 1997
Revised: 4 September 1997
Accepted: 9 October 1997
Published online: 15 January 1998

Abstract

Aqueous micellar solutions of ionic/neutral block copolymers have been studied by light scattering, small angle neutron scattering and small angle X-ray scattering. We made use of a polymer comprised of a short hydrophobic block (polyethylene-propylene) PEP and of a long polyelectrolytic block (polystyrene-sulfonate) PSSNa which has been shown previously to micellize in water. The apparent polydispersity of these micelles is studied in detail, showing the existence of a few large aggregates coexisting with the population of micelles. Solutions of micelles are found to order above some threshold in polymer concentration. The order is liquid-like, as demonstrated by the evolution with concentration of the peak observed in the structure factor (), and the degree of order is found to be identical over a large range of concentrations (up to 20 wt%). Consistent values of the aggregation number of the micelles are found by independent methods. The effect of salt addition on the order is found to be weak.