Highly stretchable six-leaf hand structure electrodes prepared by sacrificial layer method, resistant to sweat erosion, for EMG and ECG signal detection

Recently, wearable flexible electronic devices have become more widely used in detecting human physiological signals, so higher demands have been placed on flexible stretchable electrodes directly attached to the human body, which need to have better mechanical tensile properties, anti-fatigue properties, and chemical stability. In this paper, the four-segment hand structure is optimized to obtain the four-leaf hand structure, which reduces the maximum stress value when the electrode is stretched and decreases the probability of electrode fracture. Further, the structure of the electrode is optimized by changing the number of nodes, the six-leaf hand structure electrode is obtained. The six-leaf hand structure electrode has lower tensile stress and stability. The substrate-free six-leaf hand structure electrode prepared by the sacrificial layer method has a much higher stretchability than the electrode with a substrate layer due to the bonding of the substrate-free layer, and there is no significant change in the resistance value during the stretching process. The screen-printed waterproof-coated six-leaf hand structure electrode has good sweat resistance and can be used for ECG and EMG detection.