Paper Number
SC13 James Swan Memorial Symposium
Session
Suspensions and Colloids
Title
Sticky and polarizable nanoparticles: Processing conditions to achieve anisotropic structure
Presentation Date and Time
October 10, 2022 (Monday) 4:05
Track / Room
Track 1 / Sheraton 4
Authors
- Reed, Kelsey M. (Massachusetts Institute of Technology, Department of Chemical Engineering)
- Swan, James W. (Massachusetts Institute of Technology, Chemical Engineering)
- Doyle, Patrick S. (Massachusetts Institute of Technology, Department of Chemical Engineering)
Author and Affiliation Lines
Kelsey M. Reed, James W. Swan and Patrick S. Doyle
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
Speaker / Presenter
Reed, Kelsey M.
Keywords
computational methods; colloids; directed systems
Text of Abstract
Anisotropic materials are of interest for a variety of applications ranging from biomedical technologies, to oil and gas operations, to consumer care products. Discovery of novel anisotropic materials and understanding of the processing conditions necessary to achieve a desired structure is thus an active area of soft matter research. We present a simulation study of a novel anisotropic material composed of a mixture of attractive and polarizable nanoparticles, that is formed via a specified processing scheme.
It is well known that magnetic nanoparticles in an external magnetic field will polarize and form chains or other structures based on the strength and implementation of the applied field. It is also well known that nanoparticles that interact via attractive short-range potentials will aggregate and form structures dictated by the strength of the interparticle interactions. While both of these systems have been studied in detail separately, to our knowledge there is little work in the area of materials composed of attractive nanoparticles in which some fraction of the particles are also polarizable in the presence of an applied magnetic field. The space of driving forces for self-assembly is two-dimensional: thermal and magnetic, which allows for the scalable design of hierarchical microstructures with tailored material properties.
We will present the results from Brownian dynamics simulations of attractive colloids in which some fraction of the particles are also polarizable. We use a mutual dipole model, which accounts for many-body interactions, to model the dipole interactions between magnetic particles and the depletion interaction as the attractive potential between particles. We will describe the processing conditions used to achieve the anisotropic structure and describe quantitatively how the microstructure differs from that of a pure depletion gel. These results highlight the use of simulations to investigate novel colloidal materials formed via specific processing conditions.