Zhejiang Key Laboratory of Plastic Modification and Processing Technology, College of Materials Science & Engineering, Zhejiang University of Technology, Hangzhou 310014, PR China.
ACS Appl Mater Interfaces. 2024 Sep 18;16(37):49813-49822. doi: 10.1021/acsami.4c10854. Epub 2024 Sep 4.
Wearable electronics for long-term monitoring of physiological signals should be capable of removing sweat generated during daily motion, which significantly impacts signal stability, human comfort, and safety of the electronics. In this study, we developed a double-layer polyurethane (PU) membrane with sweat-directional transport ability that can be applied for monitoring strain signals. The PU membrane was composed of a hydrophilic, conductive layer and a relatively hydrophobic layer. The double-layer PU composite membrane exhibited varied pore size and opposite hydrophilicity on its two sides, enabling the spontaneous pumping of sweat from the hydrophobic side to the hydrophilic side, i.e., the directional transport of sweat. The membrane can be used as a strain sensor to monitor motion strain over a broad working range of 0% to 250% with high sensitivity (GF = 4.11). The sensor can also detect simple human movements even under sweating conditions. We believe that the strategy demonstrated here will provide new insights into the design of next-generation strain sensors.
用于长期监测生理信号的可穿戴电子产品应该能够去除日常运动中产生的汗液，因为这会显著影响信号稳定性、人体舒适度和电子产品的安全性。在本研究中，我们开发了一种具有排汗功能的双层聚氨酯（PU）膜，可用于监测应变信号。PU 膜由亲水、导电层和相对疏水层组成。双层 PU 复合膜的两侧具有不同的孔径和相反的亲水性，能够实现从疏水区到亲水区的自发汗液泵送，即汗液的定向传输。该膜可用作应变传感器，在 0%至 250%的宽工作范围内以高灵敏度（GF=4.11）监测运动应变。即使在出汗的情况下，传感器也可以检测到简单的人体运动。我们相信，这里展示的策略将为下一代应变传感器的设计提供新的思路。
