Preparation and Tracking of Oblate Core–Shell Polymethyl-Methacrylate Ellipsoids
Year: 2020
Type: article
Abstract: Although single-particle level studies on prolate ellipsoidal colloids are relatively abundant, similar studies on oblate ellipsoids are rare because suitable model systems are scarcely available. Here, we present the preparation of monodisperse hard core-shell oblate ellipsoids that can be imaged and tracked in 3D with confocal laser scanning microscopy. Using a thermomechanical squeezing method, we transform spherical core-shell polymethyl-methacrylate (PMMA) particles into oblate ellipsoids. We show how the shape polydispersity as well as the aspect ratio of the obtained oblate ellipsoids can be controlled. In addition, we discuss how the core-shell geometry limits the range of aspect ratios because of the different viscoelastic properties of the cross-linked PMMA core and linear PMMA shell. We further demonstrate imaging of the core-shell oblate dispersions on a single-particle level in real space and time and the tracking of position and orientation using our recently developed tracking algorithm for anisotropic core-shell colloids. Our results thus provide the tools for the future investigation of the behavior of oblate ellipsoids, especially in dense suspensions.
Source: Langmuir
Authors: Markus Voggenreiter, Jörg Roller, John Geiger, Lukas Ebner, Andreas Zumbusch, Janne-Mieke Meijer
Institutions: University of Konstanz, Eindhoven University of Technology
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3094048705