Abstract: In order to improve the working range of the sensor, the modified carbon nanotubes were selected as the conductive material and spandex yarn was used as the flexible substrate,the required conductive yarn was fabricated by the layer-by-layer assembly method and then the yarn strain sensors with different braiding angles were prepared by braiding method. The effects of different braiding angles on various sensing performances were discussed.As the braiding angle increases, the sensor sensitivity gradually decreases. Under a strain of 0~40%, the sensitivity of the yarn sensor with an angle of 10°, 20° and 30° braid is 181.1, 162.2, and 79.7, respectively. The fast response time increases from 175 ms to 259 ms with increasing braiding angle. The stability of the sensor under creep conditions is independent of the braiding angle. The resistance of yarn sensors with different braiding angles decreases with time basically the same when constant strain is maintained.When the braiding angle is 20°, the sensing range performs the maximum up to 150%, and the minimum monitoring range can reach 0.2%. Low hysteresis response is also exhibited in sensing process (the hysteresis level is only 0.2%),which can monitor the resistance signal stably under different strain conditions. The modified carbon nanotube braided yarn sensor has potential applications in flexible wearable sensors and other fields.

Key words: yarn strain sensor, braiding angle, carbon nanotube modification, strain sensing performance, sensitivity

摘要： 为了提高传感器的应变范围,选用改性碳纳米管为导电材料、氨纶纱为柔性基体,通过层层组装法制成所需导电纱后,采用编织法制备成不同编织角度的纱线应变传感器,并讨论不同编织角对各种传感性能的影响。研究发现:随着编织角的增加,传感器灵敏度逐渐降低,在拉伸0～40%应变下,10°、20°、30°编织角纱线传感器灵敏度分别表现为181.1、162.2、79.7。快速响应时间随着编织角的增加从175 ms增加至259 ms。在蠕变条件下,该传感器的稳定性与编织角度无关;保持恒定应变时,不同编织角纱线传感器电阻随时间的下降基本一致。当编织角为20°时,传感范围表现最大,可达150%,最小监测范围可至0.2%,同时在传感过程中表现出较低的滞后响应(滞后水平仅为0.2%),该传感器可在不同应变条件下稳定监测电阻信号。改性碳纳米管编织纱线应变传感器在柔性可穿戴传感器等领域具有潜在的应用价值。

关键词: 纱线应变传感器, 编织角, 碳纳米管改性, 应变传感性能, 灵敏度