Paper Number
PO37 

Session
Poster Session

Title
Magneto-rheological characterization of magnetically-responsive polymer-nanoparticle suspensions

Presentation Date and Time
October 12, 2022 (Wednesday) 6:30

Track / Room
Poster Session / Riverwalk A

Authors (Click on name to view author profile)

  1. Neal, Christopher A. (University of Minnesota, Twin Cities, Chemical Engineering and Materials Science)
  2. Quan, Michelle C. (University of Minnesota, Twin Cities, Chemical Engineering and Materials Science)
  3. Chibambo, Nondumiso (University of Minnesota, Twin Cities, Chemical Engineering and Materials Science)
  4. Calabrese, Michelle A. (University of Minnesota, Chemical Engineering and Materials Science)

Author and Affiliation Lines (in printed abstract book)
Christopher A. Neal, Michelle C. Quan, Nondumiso Chibambo and Michelle A. Calabrese
Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455

Speaker / Presenter 
Neal, Christopher A.

Keywords
colloids; composite rheology; directed systems; polymer solutions; suspensions

Text of Abstract
Magneto-rheological control of ferromagnetic nanoparticle suspensions has long been utilized for the development of rapidly-switchable dampers, valves and robotics. Under the application of magnetic fields, magnetically-responsive nanoparticles align into chains in the direction of magnetic field lines, increasing dynamic moduli and stiffening magneto-rheological elastomers. In this work, we investigate the magneto-rheological behavior of solutions of poly(N-isopropyl acrylamide) and magnetically susceptible iron oxide-containing nanorods of varying aspect ratios synthesized via co-precipitation of iron salts. In particular, we examine the changes in the onset of non-linear deformation and the yield stress as quantified through amplitude sweeps and flow curves, respectively. Results of this work suggest that the use of anisotropic iron oxide-containing nanorods decreases the nanoparticle content required in a sample to induce changes in sample microstructural anisotropy. Understanding how the onset of non-linear deformation and yield stresses vary as functions of magnetic field strength and nanoparticle content will aid in painting the phenomenological picture of anisotropic nanoparticle alignment through magnetic field application.