The ultra-thin and porous nanomesh‐type elastic conductor is highly compliant and because its conductivity changes when it is stretched, it can be used to detect movement. So the researchers anticipate these conductors could be utilized as breathable strain sensors for precise joint motion monitoring and as breathable sensing electrodes for continuous electrophysiological signal recording.
In a paper titled “Highly Stretchable Metallic Nanowire Networks Reinforced by the Underlying Randomly Distributed Elastic Polymer Nanofibers via Interfacial Adhesion Improvement” published in the Advanced Materials journal, the researchers detail a simple fabrication process, designing a layer‐by‐layer polyurethane nanofibers/silver nanowires (PU Nfs/Ag NWs) mesh bonded via interfacial hydrogen bonding. The mesh has a reported conductivity of 9190 S cm−1, can be stretched to 310% (over three times its initial length) while being durable (82% resistance increase after 1000 cycles of deformation at 70% tensile strain).
The authors attribute the high conductivity to the direct contact between the Ag NWs in the mesh, and the durable mechanical properties to a synergistic effect of the layer‐by‐layer structure and the strong hydrogen bonding between the Ag NWs and the PU NFs.
An important benefit for mass applications, the stretchable conductor mesh can be obtained via solution processes. Next the authors aim to improve the stretchability of the new material by using longer silver nanowires. They will experiment with other combinations of materials and probe the applicability of these breathable conductors in real-time health monitoring systems and soft robotics.
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