An Ultrastretchable Electrical Switch Fiber with a Magnetic Liquid Metal Core for Remote Magnetic Actuation

Abstract

In this work we describe a soft and ultrastretchable fiber with a magnetic liquid metal (MLM) core for electrical switches used in remote magnetic actuation. MLM was prepared by removing the oxide layer on the liquid metal and subsequent mixing with magnetic iron particles. We used SEBS (poly[styrene-b-(ethylene-co-butylene)-b-styrene]) and silicone to prepare stretchable elastic fibers. Once hollow elastic fibers form, MLM was injected into the core of the fiber at ambient pressure. The fibers are soft (Young’s modulus of 1.6~4.4 MPa) and ultrastretchable (elongation at break of 600~5000%) while maintaining electrical conductivity and magnetic property due to the fluidic nature of the core. Magnetic strength of the fibers was characterized by measuring the maximum effective distance between the magnet and the fiber as a function of iron particle concentration in the MLM core and the polymeric shell. The MLM core facilitates the use of the fiber in electrical switches for remote magnetic actuation. This ultrastretchable and elastic fiber with MLM core can be used in soft robotics, and wearable and conformal electronics.

Emerging Liquid Metal Biomaterials: From Design to Application

“…Functionalization of LMs with other materials can further enhance their stimulus‐responsive ability, facilitating the application in biomedical fields ( Table 5 ). [ 18,23,37,43,59,61,67,69–78 ]…”

“…Functionalization of LMs with other materials can further enhance their stimulus-responsive ability, facilitating the application in biomedical fields (Table 5). [18,23,37,43,59,61,67,[69][70][71][72][73][74][75][76][77][78] Surface-modifying LM with materials that possess strong light absorption and photothermal conversion capabilities can further boost the overall light responsiveness. The light-responsive EGaIn nanospheres were designed with the decoration of graphene quantum dots (GQDs) by sonication (Figure 6a).…”

“…With good biocompatibility and fluid properties, LMs can be adapted to complex biological systems, showing great potential Microwave responsiveness Microwave dynamic therapeutics Galinstan Fe particle [71] Magnetic responsiveness Bioelectrode Galinstan Fe particle [18] Antibiosis EGaIn Oxidation [23] Magnetothermal therapy EGaIn Carbonyl Fe particle [75] Flexible viscoelastic sensor Galinstan Carbonyl Fe particle [76] Strain sensor Ga Magnetic Fe particle [77] Strain sensor Ga RGO [70] Light responsiveness Photothermal therapy Ga GQDs [37] Drug delivery EGaIn Mg [43] Photothermal therapy…”

Liquid Metal Patterned Stretchable and Soft Capacitive Sensor with Enhanced Dielectric Property Enabled by Graphite Nanofiber Fillers

“…Gallium based liquid metals, especially EGaIn, have attracted great interest as conducting elements for application in soft and stretchable electronics due to their remarkable properties such as "infinite" stretchability, metallic conductivity, and fluidity near room temperature [32,34,[79][80][81][82][83]. In a liquid state, they can easily be injected or vacuum filled into microchannels, capillaries, and tubing under appropriate dimensional and pressure conditions or can be patterned on surface of substrates by various unorthodox non-lithograpic methods such as direct writing, stencil printing, and magnetic field guided patterning by formation of liquid metal inks [31,79,80,84].…”

Magnetic Behavior of an Iron Gluconate/Polyaniline Composite

“…As a result, the metal-free magnetic polymer's instability is a disadvantage in applications. Recently, polymers with magnetism were investigated using a combination of inorganic materials [4][5][6][7][8]. The combination of inorganic materials and conducting polymers is used in this study to create air-stable magnetic-electrical conducting plastics.…”