Pressure-sensitive material for high-temperature and high-pressure sensor and preparation method thereof

Abstract

The invention discloses a pressure-sensitive material for a high-temperature and high-pressure sensor. The pressure-sensitive material is prepared by mixing the following raw materials in parts by weight: 100 parts of silicon rubber, 5 to 7 parts of conductive carbon black, and 0.5 to 2 parts of silicon dioxide or core-shell structure type silicon dioxide, wherein the silicon dioxide is non-conductive silicon dioxide; the core-shell structure type silicon dioxide is silicon dioxide coated by graphene oxide or silicon dioxide coated by reduced graphene oxide. The pressure-sensitive material has the advantages that by adding the nonconductive silicon dioxide, the pressure sensitivity of the pressure-sensitive material can be adjusted, so that the pressure-sensitive material can maintain a good pressure sensitivity property under the high-temperature and high-pressure conditions; the pressure-sensitive stability is better, and the pressure response is good.

Description

technical field [0001] The invention belongs to the technical field of pressure-sensitive materials and preparation thereof, and in particular relates to a pressure-sensitive material used for high-temperature and high-pressure sensors and a preparation method thereof. Background technique [0002] Over the years, people have conducted various researches on pressure sensitive sensors, and developed various pressure sensors, the more commonly used are ceramic pressure sensors, metal strain type pressure sensors, piezoelectric pressure sensors, capacitive pressure sensors and semiconductor pressure sensors, etc. . At present, the materials used for pressure sensors under high temperature and high pressure conditions are mainly inorganic materials, such as semiconductor silicon chip pressure-sensitive materials, capacitive ceramic pressure-sensitive materials, and the like. Zhao Yulong et al. used SIMOX, Separate by Implant Oxygen to form an SOI (Silicon On Insulator) insulati...

AI Technical Summary

Problems solved by technology

But unfortunately, for the research on conductive polymer composite pressure-sensitive materials, most of the research is on the pressure-sensitive behavior of polymer composite materials under the action of small pressure at room temperature, such as hearing aids of several Pascals, robotic artificial skins of several thousand Pascals, etc. , health monitoring equipment of tens or even hundreds of kilopascals, etc., but there are few studies on the industrial application of polymer composite materials under conditions of greater pressure (2500KPa) and higher temperature (within 200°C), the main reason is that The following aspects: (1) The improvement of sensitivity is limited by the method of blending two or more conductive fillers, and a higher content of conductive fillers destroys the mechanical strength of the material, resulting in a higher pressure. It is more difficult to meet the demand for the pressure-sensitive performance of the material; (2) by adding a compatibilizer [such as quaternary ammonium salt surfactant, poly(3-hexylthiophene), etc.] to improve the contact between the polymer matrix and the conductive filler Although interfacial interaction can improve the dispersion state of the conductive filler and improve the response of the conductive network to external stress to realize the regulation of the pressure-sensitive performance, but this method often reduces the conductivity of the conductive filler and increases the threshold. It is difficult to accurately measure the resistivity of the material, which affects its use as a pressure sensor; (3) The conductive network built by the conductive particles in the polymer composite material will be irreversibly damaged under excessive pressure, so that the conductive performance of the composite material cannot be Keep

Images