Structure and Dynamics of Ultra‐Low‐Crosslinked Microgels

Journal of Polymer Science

Abstract

ABSTRACT Concentrated suspensions of small ultra‐low crosslinked microgels are investigated with scattering and steady shear rheology to capture their equilibrium dynamics. We combine viscosimetry, dynamic light scattering, and small‐angle neutron and x‐ray scattering in dilute suspensions and show that the synthesis without the addition of any crosslinker agent and in presence of high concentrations of surfactants led to small ultra‐soft microgels. Although the slow relaxation time increases exponentially with the generalized packing fraction, , the relative viscosity follows a power‐law dependence on , with . The interplay between characteristic lengths (mesh size vs. overall size of the microgel) and the enhanced polymeric contributions of the shell make these microgels ultra‐soft, enabling the formation of viscoelastic fluids even in overcrowded conditions.

Authors 5

1. Nikolaos A. Burger corresponding

   Lund University

   Affiliation as printed

   Division of Physical Chemistry Lund University Lund Sweden

2. Alexander V. Petrunin Aachen Institute of Physical Chemistry

   RWTH Aachen University

   Affiliation as printed

   Institute of Physical Chemistry, RWTH Aachen University Aachen Germany

3. Ann E. Terry

   Lund University · MAX IV Laboratory

   Affiliation as printed

   MAX IV Laboratory Lund University Lund Sweden

4. Ralf Schweins

   Institut Laue-Langevin

   Affiliation as printed

   Institut Laue‐Langevin ILL DS/LSS Grenoble France

5. Andrea Scotti corresponding

   Lund University

   Affiliation as printed

   Division of Physical Chemistry Lund University Lund Sweden