Abstract: The flexible thermoplastic polyurethane sheets with the single- and dual-level microcolumn arrays were rapidly prepared by using injection-compression molding with two different template design schemes. The microstructured flexible sensing substrates were obtained after cutting the sheets and spraying gold layer on them. The flexible pressure sensors were prepared by assembling the sensing substrates with the single-/dual-level microcolumns and the flat sensing substrate face-to-face， which were denoted as sensor 1 and sensor 2， respectively. The simulated results show that higher contact stress appeares around the edges on the top surfaces of the microcolumns under pressure. The longitudinal sections of the single- and dual-level microcolumns under pressure exhibit  “bowl” and “bud” geometries， respectively. The dual-level microcolumn can be deformed under lower pressure， and the contact deformation and contact area with the flat sensing substrate under pressure are larger. Therefore， compared to sensor 1， sensor 2 exhibits a higher sensitivity（0.53 kPa-1,0~1 kPa）， shorter response time/relaxation time（100 ms/80 ms）， lower detection limit（about 58 Pa）. Sensor 2 has a wide detection range（0.058～600 kPa）and maintaines a relatively stable piezoresistive response in 4000 cycles of compression/release tests（under a peak pressure of about 500 kPa）， which is ascribed to higher pressure resistance of the microcolumn. Sensor 2 may accurately detect human pulse, vocalisation and movement, demonstrating its potential for smart wearable applications. 

Key words: flexible pressure sensor, surface microstructure, sensitivity, thermoplastic polyurethane, injection-compression molding

摘要： 以2种不同的模板设计方案，采用注射压缩成型制备单级和双级微柱阵列的热塑性聚氨酯柔性薄片，经裁剪、喷金后得到微结构柔性传感基片。将单级和双级微结构柔性传感基片分别与平整柔性传感基片面对面封装成柔性压力传感器1和传感器2。模拟结果表明，受压后微柱顶面上边缘区域接触应力较大。单级和双级微柱受压后纵截面分别呈“碗”和“花苞”状结构；双级微柱在较小压力作用下即可发生形变，且其受压后与平整传感基片的接触形变和接触面积较大。因此，相比传感器1，传感器2具有较高灵敏度（0.53 kPa-1，0~1 kPa）、较短响应时间/松弛时间（100 ms/80 ms）和较低检测限（约58 Pa）。微柱较高的耐压性使传感器 2具有较宽的检测范围（0.058～600 kPa），能在4000次的循环压缩/释放测试（峰值压力约500 kPa）中保持较稳定的压阻响应。传感器 2可准确检测人体脉搏、发声和运动，表明其具有应用于智能可穿戴领域的潜能。

关键词: 柔性压力传感器, 表面微结构, 灵敏度, 热塑性聚氨酯, 注射压缩成型