基于碳纤维浆料的柔性薄膜弯曲传感器制备与研究

Preparation and Study of Flexible Thin Film Bending Sensors Based on Carbon Fiber Slurry

摘要:

以碳纤维粉末为功能性填料和乙基纤维素为胶粘剂，开发了一种低成本碳基传感浆料，将碳纤维浆料直接刮涂至聚酰亚胺薄膜表面而形成碳纤维传感层，在以铜箔为电极，制备出结构简单的碳纤维弯曲传感器。同时，探究了碳纤维含量对弯曲传感器性能的影响。结果表明：当碳纤维含量为0.02 g?mL^-1时，碳纤维粉末被乙基纤维素完全包覆，难以形成导电通路，无弯曲传感特性；随着碳纤维含量的逐渐增加，碳纤维膜内部形成良好的导电通路，随之产生大量的孔洞甚至微裂纹，有利于传感器精准识别不同弯曲角度，并且具有双向识别特性。通过进一步深入探究碳纤维含量对弯曲传感器的迟滞性和稳定性的影响发现，当碳纤维含量为0.04 g?mL^-1时，弯曲传感器具有较小的迟滞性、优异的稳定性和机械耐久性。

Abstract:

In this paper， a low-cost carbon-based sensing slurry was developed using carbon fiber powder （CFP） as a functional filler and ethyl cellulose as an adhesive. The carbon fiber slurry was directly scraped onto the surface of a polyimide film to form a carbon fiber sensing functional layer. Then a simple structured carbon fiber bending sensor was fabricated using copper foil as the electrode. The effect of CFP content on the performance of the bending sensor was explored. The results show that when the carbon fiber content is 0.02 g·ml^-1， the CFP is completely covered by ethyl cellulose， making it difficult to form a conductive pathway and no bending sensing characteristics. As the carbon fiber content gradually increases， a good conductive pathway is formed inside the CFP membrane， and a large number of holes and even micro-cracks are subsequently produced， which is conducive to the accurate identification of different bending angles and bidirectional identification characteristics of the sensor. The hysteresis and stability of the CFP bending sensor was performed in depth. The best sensing performance of 0.04 g·ml^-1 CFP bending sensor was obtained with less hysteresis， excellent stability and mechanical durability.