The Suitability of 3-D Printed Eutectic Gallium-Indium Alloy as a Heating Element for Thermally Active Hydrogels
- PDF / 550,222 Bytes
- 6 Pages / 595.32 x 841.92 pts (A4) Page_size
- 33 Downloads / 144 Views
The Suitability of 3-D Printed Eutectic Gallium-Indium Alloy as a Heating Element for Thermally Active Hydrogels Charles Hamilton1,2, Gursel Alici2,3, Geoff Spinks2,3, Marc in het Panhuis 1,2 1
Soft Materials Group, School of Chemistry, University of Wollongong, Wollongong 2522 NSW, Australia 2 Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, Wollongong 2522, NSW, Australia 3 School of Mechanical, Materials, and Mechatronic Engineering, University of Wollongong, Wollongong, NSW 2522, Australia ABSTRACT We report the use of a novel extrusion tip that allows for the omnidirectional printing of eutectic gallium-indium (eGaIn) alloy onto the surface of hydrogel materials into complex 2-dimensional patterns. The use of these printed soft “wires” as an electrothermal heating element for soft robotics purposes was explored. Heating of the eGaIn structures encapsulated in an alginate/acrylamide ionic-covalent entanglement hydrogel was measured by a thermal imaging camera. It was determined that eGaIn is a suitable material for use in future soft robotics applications as an electrothermal heating element to actuate thermally responsive N-isoproylacrylamide hydrogels.
INTRODUCTION The field of soft robotics has seen the benefit of tough hydrogel materials in a variety of applications in fields such as biomedical, waste management, soft robotics, and others [14]. Recently, stimuli responsive hydrogels such as thermally responsive Nisopropylacrylamide (NIPAM) have been determined to be suitable materials to serve as actuators for many soft robotics applications [5, 6]. However, a practical method of actuation has yet to be determined for these materials, but one approach would be to use electrothermal heating by incorporating a soft conductor. Recently, liquid metal eutectic gallium-indium (eGaIn) alloy has been explored in various applications and has shown great potential as a compliant conductive material [7, 8]. One notable advantage of eGaIn, aside from its metallic conductivity and low toxicity, is the spontaneous formation of a passivating oxide layer that allows for the formation of stable microstructures [9, 10]. In previously reported work, the use of eGaIn in many applications has revolved around the ability to manipulate this oxide layer [11]. However, the inherent properties of eGaIn have made it difficult to process and many devices have required the use of complicated multi-step processes incorporating micro-molding techniques [12]. Newly developed techniques, such as embedded printing, have simplified the process but the material’s unfavorable interaction with hydrous surfaces, described as the formation of a “slip-layer,” has restricted its use to primarily silicone based substrates such as PDMS [13, 14]. In this study, we describe the use of a custom extrusion tip that can print eGaIn onto hydrous surfaces in continuous complex 2-dimensional patterns. The eGaIn is then encapsulated into the completely 3D-printed hydrogel d
Data Loading...
