Graphene filled silicone rubber composite material piezoresistive sensor and preparation method thereof

Abstract

The invention discloses a graphene filled silicone rubber composite material piezoresistive sensor and a preparation method thereof, and belongs to the technical field of measurement. The method comprises the steps of taking grapheme whose bulk density is 0.20g / cm<3>, diameter is 5 microns, thickness is less than 15nm and carbon content is greater than 98wt% as a conductive filler and silicone rubber whose dielectric constant is 3.0 and dielectric strength is 15kV / mm as a matrix phase, preparing a piezoresistive film based on a graphene filled silicone rubber composite material by employing a solution mixing method and a spin-coating method, and then preparing the piezoresistive film and a polyimide copper cladded film into the graphene filled silicone rubber composite material piezoresistive sensor by employing a hot-pressing encapsulation method. The piezoresistive sensor prepared with the method disclosed by the invention has monotonous piezoresistive characteristic, high sensitivity, large measuring range and good flexibility, and can be applied to fields such as electronic skin preparation, curved surface interlayer pressure measurement, and the like.

Description

technical field [0001] The invention belongs to the field of measurement technology, in particular to the preparation of flexible pressure sensors. Background technique [0002] With the development of science and technology, thin flexible pressure sensors are playing an increasingly important role in engineering applications. Conductive polymer composites have piezoresistive properties, flexibility, and easy processing, so they can be used as sensitive materials for flexible pressure sensors. Nano powders are usually used as reinforcing agents and conductive fillers in composite materials. The conductive filler forms a conductive channel through the tunnel effect or contact conduction, and when the conductive channel penetrates the matrix, an effective conductive channel is formed to contribute to the conductivity of the composite material. When the external pressure and deformation act on the composite material, the effective conductive channel changes, which causes the ...

AI Technical Summary

Problems solved by technology

If the content of conductive filler is too small, the reinforcing effect is insufficient and an effective piezoresistive network cannot be formed; if the content of conductive filler is too large, it will inevitably affect the flexibility of the composite material; the conductive content directly determines the monotonicity and sensitivity of piezoresistive characteristics, etc. Important indicators