title: Structural behaviour of sodium hyaluronate in concentrated oppositely charged surfactant solutions.
abstract: This work discusses the polyelectrolyte sodium hyaluronate (HA) and its polyelectrolyte/surfactant complexes (PESCs) with tetradecyltrimethylammonium bromide (TTAB) in the semi-dilute regime of HA and at high concentrations of TTAB. The structure and flow properties in the surfactant excess region were studied by light scattering and small angle neutron scattering (SANS) as well as by rheology. The unique behaviour of HA to maintain its high viscosity was observed even at very high TTAB concentrations of 496 mM and this effect was systematically studied in the concentration range from 1 to 25 mM HA. From the data, it could be concluded that: (1) extended rod-like structures of the PESCs prevent molecular dissolution of HA by TTAB. (2) HA and TTAB micelles interact rather weakly as seen by a low fraction of bound micelles. (3) At very high TTAB concentrations a decompaction of PESCs (fractal dimension Dfgoing from 2.0 to 1.2) occurs with increasing HA concentration but (4) both the entanglement of HA and the structure of the micelles are not affected.
authors.affiliation: Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Technische Universität Berlin, D-10623 Berlin, Germany. michael.gradzielski@tu-berlin.de and Institut Laue-Langevin (ILL), DS/LSS, 71 Avenue des Martyrs, CS 20 156, F-38042 Grenoble CEDEX 9, France.
authors.forename: Philipp
authors.identifier: http://orcid.org/0000-0002-5260-1399
authors.initials: P
authors.lastname: Buchold
authors.affiliation: Institut Laue-Langevin (ILL), DS/LSS, 71 Avenue des Martyrs, CS 20 156, F-38042 Grenoble CEDEX 9, France.
authors.forename: Ralf
authors.initials: R
authors.lastname: Schweins
authors.affiliation: Jülich Centre for Neutron Science JCNS, Forschungszentrum Jülich GmbH, Outstation at MLZ, Lichtenbergstrasse 1, 85747 Garching, Germany.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Di
authors.affiliation: Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Technische Universität Berlin, D-10623 Berlin, Germany. michael.gradzielski@tu-berlin.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Gradzielski