基于双层微结构的碳纳米管柔性应变传感器的研究

Study on Bilayer-Microstructure Flexible Strain Sensors Based on Carbon Nanotubes

设计了一种具有双层微结构的柔性压阻式应变传感器,并进行了制备方法研究。通过在半固化的环氧树脂基底(Ecoflex~? 00-30)表面制备形成碳纳米管(MCNTs)/环氧树脂(Ecoflex~? 00-30)复合薄膜,用毛刷制备微结构。通过测试分析可得,该柔性应变传感器具有高度可拉伸性能,可承受200%的应变,在0～80%,80%～170%,170%～195%的应变区间,GF值分别为10.5,40.5,190.5。将传感器进行可穿戴运动监测测试,可验证本传感器既可以实现手指和手腕运动等大动作应变的监测,输出电阻值相对变化达到7.5倍;也可以监测肌肉形变弯曲等小应变,输出电阻值相对变化达到1.4倍。

A bilayer-microstructure flexible piezoresistive strain sensor is proposed and the corresponding fabrication process is also presented. The bilayer-microstructure was achieved by using a brush to transfer carbon nanotubes into the elastomer(Ecoflex 00-30)to form a composite layer,on which another layer of pure carbon nanotubes was constructed afterwards. The flexible strain sensors based on the bilayer-microstructure exhibit high tensile properties and can therefore withstand strain of up to200%. The experimental results show that the sensor gauge factor(GF)values of10.5,40.5,190.5 correspond to the strain ranges of 0~80%,80%~170%,170%~195%,respectively. The as-prepared sensors can not only monitor large human motion strains such as finger and wrist movements,but also detect small strains including muscle deformation and bending. The output resistances of the former and the latter can be increased to 7.5 times and1.4 times,respectively.