纳米银-聚合物菱形剪纸薄膜应变传感特性的研究

Strain sensing characteristics of silver nanoparticle/polymer diamond kirigami film

采用银镜制备法和激光切割技术获得了纳米银颗粒/聚二甲基硅氧烷剪纸结构薄膜,并系统地研究了薄膜作为柔性应变传感器的力学及压阻特性。将数值模拟与实验相结合,测量了传感薄膜的应变比γ、压阻滞回特性、线性度及压阻敏感性,重点探讨了薄膜制备工艺、结构参数与上述薄膜传感特性的定量关系。结果表明,在给定结构下,结构薄膜整体与结构单元的应变比γ为常数,反映了结构薄膜的变形特性,是理想的力学性能表征参数。菱形剪纸结构薄膜具有量级可达200的大应变比,即在大应变下,材料的实际应变很小。这一特点极大地提升了薄膜的应变测量范围、压阻稳定性、线性度,并保持了合理的压阻灵敏度。

Silver nanoparticle/polydimethylsiloxane diamond kirigami films were synthesized by silver mirror preparation and laser etching, and mechanical and piezoresistive properties were systematically investigated for the films as flexible tactile strain sensors. Numerical and experimental techniques were combined to study the strain ratio γ, piezoresistive hysteresis, linearity, and sensitivity of the films.Quantitative relations between the synthesis techniques, size parameters, and sensing propertiesof the kirigami films were analyzed. Results show that for a given structure, the ratio γ between the overall strain and the local strain of structural units was a constant. It indicates the deformability of the structure and is an ideal parameter to characterize the mechanical properties of the kirigami films. The strain ratio of the diamond kirigami films was large, with the magnitude up to 200, i.e., the actual material strain was small when the film is under a large strain. This property can greatly improve the scope of strain measurement, the piezoresistive stability, and linearity of the kirigami films, while maintainingits piezoresistive sensitivity.