基于电流体喷墨打印直写纳米银浆的柔性应变传感器及其应用

Flexible Strain Sensor Based on Electrohydrodynamic Jet Printing with Directly Writing of Nano-Silver Paste and Its Application

柔性传感器在皮肤信号监测方面应用广泛,但传统印刷工艺难以满足其高精度定位、高黏度墨液印刷的制备要求。利用电流体喷墨打印工艺在高黏度材料制备方面的优势,使用纳米银浆制作用于人体皮肤信息采集的电阻式柔性应变传感器。探索电喷印工艺参数对导电线宽的影响规律,使用内径0.16 mm的喷嘴以30 mm/s的打印速度移动制得宽度120μm的银线。通过实验得出打印速度和喷嘴内径对银线线条宽度和质量的影响规律,利用电流体喷墨打印工艺制备出基于聚二甲基硅氧烷柔性基底和纳米银浆敏感层的柔性应变传感器。利用自主研制的检测系统,测试并计算出传感器应变范围在3%内时灵敏度可达172.67。最后将传感器用于多个人体部位的姿态监测,证明其具有检测微小信号的能力。测试结果证明,电流体喷墨打印工艺可用于制备柔性应变传感器,制得的柔性应变传感器在智能穿戴设备上具有应用潜力。

Flexible sensors are widely used in skin signal monitoring,but traditional printing processes are difficult to meet the manufacture requirements of high-precision positioning and high viscosity ink printing.Based on the advantages of electrohydrodynamic jet printing process in the manufacture of high viscosity materials,nano-silver paste was used to fabricate a resistive flexible strain sensor for human skin information acquisition.After exploring the influence law of the process parameters of electrohydrodynamic jet printing on the conductive line width,the silver lines with a width of 120μm were printed using a nozzle with an inner diameter of 0.16 mm moving at a printing speed of 30 mm/s.After the influence laws of the printing speed and the inner diameter of nozzle on width and quality of the silver line were obtained by experiments,a flexible strain sensor based on polydimethylsiloxane flexible substrate and nano-silver paste sensitive layer was fabricated by electrohydrodynamic jet printing.By detection using a selfdeveloped detection system and calculation,the sensitivity of the sensor can reach 172.67 when the strain range of the sensor is within 3%.Finally,the sensor was applied on several human body parts for posture monitoring,proving that the sensor has the ability to detect tiny signals.The test results prove that electrohydrodynamic jet printing is feasible in the preparation of flexible strain sensors,and the prepared flexible strain sensors have application potential in smart wearable devices.