Soft Multi-Material Magnetic Fibers and Textiles.

Magnetically responsive soft materials are promising building blocks for the next generation of soft robotics, prosthesis, surgical tools, and smart textiles. To date, however, the fabrication of highly integrated magnetic fibers with extreme aspect ratios, that can be used as steerable catheters, endoscopes, or within functional textiles remains challenging. Here, we propose multi-material thermal drawing as a material and processing platform to realize 10s of meters long soft, ultra-stretchable, yet highly resilient magnetic fibers. We demonstrate fibers with a diameter as low as 300 μm and an aspect ratio of 10 5 , integrating nano-composite domains with ferromagnetic micro-particles embedded in a soft elastomeric matrix. With the proper choice of filler content that must strike the proper balance between magnetization density and mechanical stiffness, we show fibers withstanding strains of more than 1000%, that can be magnetically actuated and lift up to 370 times their own weight. The magnetic fibers can also integrate other functionalities like micro-fluidic channels, and be weaved into conventional textiles. We show that the novel magnetic textiles can be washed and sustain extreme mechanical constraints, as well as be folded into arbitrary shapes when magnetically actuated, paving the way towards novel intriguing opportunities in medical textiles and soft magnetic systems. This article is protected by copyright. All rights reserved.