Compressible Microgels in Concentrated Suspensions: Phase Behavior, Flow Properties, and Scattering Techniques to Probe Their Structure and Dynamics

Abstract

Microgels are compressible crosslinked polymer networks in the colloidal-size domain. The capability to adapt their size, shape, and volume depending on sample concentration is a unique characteristic of these particles that largely affects both their phase behavior and flow properties. In this chapter, we start by reviewing the basic concepts to describe the swelling thermodynamics of individual microgels. Given their size and internal structure, scattering techniques are a useful tool to probe the properties of these particles in suspension. After a brief description of the basic principles of light and neutron-scattering, we focus on particular and often not discussed experimental realizations, such as cross-correlation light scattering and small-angle neutron-scattering with contrast variation; these are both relevant for accessing the microgel properties in concentrated suspension. Then, the effects of isotropic deswelling and deformation on both the suspension phase behavior and the suspension rheological properties are discussed? The chapter ends with a discussion on what we view as some of the relevant future developments and questions we ought to address within the broad field of microgels and microgel suspensions.

Authors 6

1. Andrea Scotti Aachen Institute of Physical Chemistry

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University, Institute of Physical Chemistry, 52056 Aachen, Germany

2. Urs Gasser

   Paul Scherrer Institute

   Affiliation as printed

   Paul Scherrer Institut, Laboratory for Neutron Scattering and Imaging, Forschungsstrasse 111, 5232 Villigen, Switzerland

3. A Arenas-Gullo

   Institució Catalana de Recerca i Estudis Avançats

   Affiliation as printed

   ICREA-Institucio Catalana de Recerca i Estudis Avancats, 08010 Barcelona, Spain

4. Alexis de la Cotte

   Universitat de Barcelona

   Affiliation as printed

   University of Barcelona, Institute of Complex Systems (UBICS), Martí i Franquès, 1-1., 08028 Barcelona, Spain

   University of Barcelona, Institute of Complex Systems (UBICS), Martí i Franquès, 1-1., 08028 Barcelona, Spain

5. Javier González

   Institució Catalana de Recerca i Estudis Avançats

   Affiliation as printed

   ICREA-Institucio Catalana de Recerca i Estudis Avancats, 08010 Barcelona, Spain

6. Alberto Fernández‐Nieves

   Universitat de Barcelona

   Affiliation as printed

   University of Barcelona, Institute of Complex Systems (UBICS), Martí i Franquès, 1-1., 08028 Barcelona, Spain

   University of Barcelona, Institute of Complex Systems (UBICS), Martí i Franquès, 1-1., 08028 Barcelona, Spain