Magnetic Shape Memory Polymers with Integrated Multifunctional Shape Manipulation

TLDR

Shape‑programmable soft materials that can perform multiple integrated shape manipulations—reprogrammable, untethered, fast, reversible transformations and locking—are highly desirable for soft robotics, morphing structures, and biomedical devices, yet achieving multiple shape manipulations in one material remains challenging. This study reports a novel magnetic shape memory polymer composite that achieves multiple integrated shape manipulations in a single material system. The composite contains low‑coercivity magnetic particles that heat the amorphous shape memory polymer matrix, and high‑remanence particles with reprogrammable magnetization that drive rapid, reversible shape changes under magnetic fields, with the shape locked upon cooling and sequential actuation enabled by varying particle loadings. The multifunctional shape manipulations enable applications such as soft magnetic grippers with large grabbing force, reconfigurable antennas, and sequential logic for computing.

Abstract

Abstract Shape‐programmable soft materials that exhibit integrated multifunctional shape manipulations, including reprogrammable, untethered, fast, and reversible shape transformation and locking, are highly desirable for a plethora of applications, including soft robotics, morphing structures, and biomedical devices. Despite recent progress, it remains challenging to achieve multiple shape manipulations in one material system. Here, a novel magnetic shape memory polymer composite is reported to achieve this. The composite consists of two types of magnetic particles in an amorphous shape memory polymer matrix. The matrix softens via magnetic inductive heating of low‐coercivity particles, and high‐remanence particles with reprogrammable magnetization profiles drive the rapid and reversible shape change under actuation magnetic fields. Once cooled, the actuated shape can be locked. Additionally, varying the particle loadings for heating enables sequential actuation. The integrated multifunctional shape manipulations are further exploited for applications including soft magnetic grippers with large grabbing force, reconfigurable antennas, and sequential logic for computing.