An Antifatigue Liquid Metal Composite Electrode Ionic Polymer-Metal Composite Artificial Muscle with Excellent Electromechanical Properties

Abstract

Ionic polymer–metal composites (IPMC), one of the most popular materials in the field of artificial muscle research, have attracted much attention because of their high flexibility, low drive voltage (<10 V), high force density, large deformation, and so forth. However, the results show that the serious electrode fatigue crack and water loss of traditional IPMC greatly decrease its fatigue life and limit the practical application. In this study, we developed a novel liquid metal composite electrode. A layer of eutectic gallium–indium alloy (EGaIn) liquid metal was applied to the surface of the platinum electrode of the IPMC using a mask. Because of the good self-healing performance of the liquid metal, it is expected to solve the above problems of resistance increase and water loss caused by cracks. It turns out that the prepared EGaIn/Pt-IPMC exhibits a driving force up to 120 mN and maximum fatigue life of about 25,000 s at a driving voltage of 3 V. Compared with the best work reported, the fatigue strength of EGaIn/Pt-IPMC was increased by about 210%, and the maximum driving force of EGaIn/Pt-IPMC prepared by a single-layer basement membrane was between the IPMC prepared by 4–6 layer basement membrane. The electromechanical properties were significantly improved, and it is expected to realize a series of bionic applications.

Preparation and characterization of transparent polymeric electrolyte containing ionic liquid with long alkyl chains for electroactive polymers

“…For example, the self-healing function can be achieved by using liquid metal composites as electrodes. 58,59 Additionally, it has been reported that PVA is also a promising self-healing material, based on the principle of reversible dynamic chemical bonds. 60 Thus, the self-healing function of iEAPs could be achievable using the PVA/IL electrolyte developed in this study.…”

Low‐Voltage Driven Ionic Polymer‐Metal Composite Actuators: Structures, Materials, and Applications

“…For example, the addition of different alcohol solutions for assistance during the electroless plating process was proposed to allow the Nafion membrane to swell more efficiently during the reduction step. [ 69 , 70 ] The metal salt ions achieve a better distribution on the surfaces of the substrate in this way. The high‐quality, homogeneous nano‐dispersed Pt electrodes obtained became the structural basis for the large deformation and fast response of IPMC.…”

“…[ 33 , 44 , 69 , 111 ] The final step is the replacement of ions that can form a larger volume of hydrated cations (such as Li ions) inside the IPMC film. [ 70 ] Since the deformation of IPMC depends on the accumulation of water molecules on the mesoscopic scale, the more water molecules there are under the action of an electric field, the more pronounced the bending of IPMC will be, and the better the actuation performance will be. After up to 24 h of saturated solution immersion, ion exchange can be completed.…”

A comprehensive survey of ionic polymer metal composite transducers: preparation, performance optimization and applications

“…Guo et al used PEDOT layer to prevent the water exchange between IPMC and the external environment and improved the working time of IPMC [116] , as shown in Figure 7E. Besides, the materials used for encapsulation of IPMC include parylene [117] , PDMS [118] , PVP [119] and liquid metal [120] .…”