This Faculty Early Career Development Program (CAREER) grant investigates multiple physical behaviors of magnetic shape memory polymers. The shape memory effect refers to the ability of a material to remember and recover a pre-programmed shape in response to a combination of magnetic and mechanical fields. These materials are composites with embedded magnetic particles in shape memory polymer matrices. They utilize superposed alternating and direct magnetic fields to regulate the stiffness and shape changing actuation of the materials. They combine untethered fast and reversible transformation, shape-locking ability, and reprogrammability in one material system and have potential applications in soft robots, flexible electronics, and biomedical devices for minimum invasive surgery. However, the complicated magneto-thermo-viscoelastic behaviors of these materials make the design of applications using these materials very challenging. The success of this work will lead to a systematic understanding of the magnetic shape memory polymer, a material model to describe the magneto-thermo-viscoelastic behavior and a multiphysics simulation platform to accelerate the design of applications. This work will provide hands-on interactive multi-disciplinary research experience for middle and high school students through 3D Printed Magnetically Actuated Soft Robots. This work will also demonstrate material research to K-12 students and the general public through the local Science and Industry Science Festival and the Ohio State University STEAM factory Franklinton Friday Events.
Soft active materials are widely used but have limitations such as slow actuation speed, irreversible actuation, or no shape-locking. Magnetic shape memory polymers overcome these limitations by integrating rapid magnetic actuation with shape memory effects in polymers. These materials use the alternative current magnetic field to control the temperature and the direct current magnetic field to actuate the materials. The coupling of magnetic actuation with thermoviscoelastic material behavior demands intensive fundamental mechanics research. This CAREER award will provide new understandings on how the interactions among magnetic particles and magnetic particles-polymer matrix can alter the thermoviscoelastic and shape memory behavior of a polymer. These understandings will enable the establishment of a thermodynamic framework for magneto-thermo-viscoelastic solids. The new framework can provide a clear description of the complicated multiphysics processes and guide the development of a new constitutive model for magneto-thermo-viscoelastic solids. The new constitutive model will be implemented into finite element analysis to simulate the magnetic and thermal actuation of magnetic shape memory polymers with complicated geometry and complicated loading conditions.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.