WO2020113807A1 - 一种用于制备柔性压阻式传感器的多孔导电浆料及其制备方法和应用 - Google Patents

一种用于制备柔性压阻式传感器的多孔导电浆料及其制备方法和应用 Download PDF

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WO2020113807A1
WO2020113807A1 PCT/CN2019/073584 CN2019073584W WO2020113807A1 WO 2020113807 A1 WO2020113807 A1 WO 2020113807A1 CN 2019073584 W CN2019073584 W CN 2019073584W WO 2020113807 A1 WO2020113807 A1 WO 2020113807A1
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conductive paste
porous conductive
sacrificial template
preparing
porous
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PCT/CN2019/073584
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English (en)
French (fr)
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彭争春
王子娅
管晓
王海飞
何楚斌
林婉儿
田小军
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深圳大学
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Priority to US17/311,361 priority Critical patent/US20220026298A1/en
Publication of WO2020113807A1 publication Critical patent/WO2020113807A1/zh

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
    • G01L9/02—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in ohmic resistance, e.g. of potentiometers, electric circuits therefor, e.g. bridges, amplifiers or signal conditioning
    • G01L9/06—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in ohmic resistance, e.g. of potentiometers, electric circuits therefor, e.g. bridges, amplifiers or signal conditioning of piezo-resistive devices
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/20—Conductive material dispersed in non-conductive organic material
    • H01B1/24—Conductive material dispersed in non-conductive organic material the conductive material comprising carbon-silicon compounds, carbon or silicon
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
    • B81B3/00—Devices comprising flexible or deformable elements, e.g. comprising elastic tongues or membranes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
    • B81C1/00—Manufacture or treatment of devices or systems in or on a substrate
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/18—Measuring force or stress, in general using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables

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  • the invention relates to a sensing material used for a piezoresistive sensor, and a preparation method and application thereof, in particular to a porous conductive paste for preparing a flexible piezoresistive sensor, and a preparation method and application thereof.
  • Flexible piezoresistive sensors are one of the key components of wearable devices, robotic electronic skins, and implanted devices.
  • Traditional semiconductor devices represented by silicon materials have limitations in their application in the above-mentioned fields due to the complex processing technology, high equipment investment costs, large environmental pollution, and lack of flexibility.
  • printing technology can prepare electronic devices on a flexible substrate, and has the advantages of simple processing technology and low equipment cost.
  • printed electronics based on organic semiconductor materials and nano-functional materials have developed rapidly in recent years.
  • the sensor device based on the piezoresistive effect has the advantages of high sensitivity, simple structure, easy to read signal, and little influence by noise.
  • the change in the contact resistance between the conductive materials of the piezoresistive sensor is proportional to the square root of the applied pressure.
  • Another effective measure is to create more microporous structures in piezoresistive materials.
  • the currently reported methods for preparing micropore structures are difficult to implement and the effects are not obvious. Therefore, developing a highly conductive porous printing paste with easy preparation and controllable pore size, and printing this paste directly on any electrode to realize a flexible or even stretchable pressure sensor device has important application value.
  • a flexible pressure sensor is constructed by printing a support member of conductive ink on the textile surface. It is characterized in that the support member is soft, stretchable and elastic, and a plurality of main traces of stretchable and elastic conductive ink or paste are printed on the support member.
  • This process mainly uses conductive ink to make the surface of the fabric form a piezoresistive pressure device. There are not many breakthroughs in the printing paste.
  • the sensor performance is mainly limited by the fabric material.
  • CN101586992 a method for preparing a pressure sensor with a nano-SiC film is disclosed, and the nano-SiC film is prepared by screen printing and sintering. This type of thin-film sensor mainly uses the design of the back-end circuit to improve sensitivity, and the force range is small, and the device does not have stretchability.
  • the object of the present invention is to provide a porous conductive paste for preparing a flexible piezoresistive sensor, and a preparation method and application thereof.
  • the porous conductive paste includes a conductive carbon material, a sacrificial template, and a polymer carrier.
  • the invention uses a sacrificial template with adjustable particle size to prepare porous conductive paste, which can greatly increase the number of nanopores or micropores after the conductive paste is formed into a film. Under the effect of stress, the conductive particles around the hole contact each other, which effectively reduces the conductivity of the material, and thus cooperates with the conductive particles to improve the sensitivity of the flexible piezoresistive sensor.
  • the adjustable size of the aperture size is helpful to adjust the sensitivity interval and can meet different practical applications.
  • the porous conductive paste can be printed, which provides a guarantee for a low-cost and high-efficiency sensor preparation process.
  • the porous conductive paste with adjustable viscosity provides a variety of options for device design and processing.
  • the first aspect of the present invention provides a porous conductive paste for preparing a flexible piezoresistive sensor, which includes a conductive carbon material, a sacrificial template, and a polymer carrier.
  • the polymer carrier includes a polymer and Organic solvent
  • the mass ratio of the polymer to the organic solvent is 1:2 to 1:3, such as 1:2 to 1:2.2, 1:2.2 to 1:2.4, 1:2.4 to 1:2.5 , 1:2.5 to 1:2.7 or 1:2.7 to 1:3, based on the total mass of conductive carbon material, sacrificial template and high molecular polymer
  • the mass percentage of the conductive carbon material is 2% to 5%, such as , 2% ⁇ 3%, 3% ⁇ 4% or 4% ⁇ 5%
  • the mass percentage of the sacrificial template is 75% ⁇ 85%, such as 75% ⁇ 77%, 77% ⁇ 81%, 81% ⁇ 82% or 82% to 85%
  • the mass percentage of the polymer is 10% to 23%, such as 10% to 14%, 14%
  • the viscosity of the porous conductive paste can be adjusted by an organic solvent to meet the needs of device printing or printing preparation.
  • the conductive carbon material is selected from one or more of conductive carbon black, carbon nanotubes and graphene sheets;
  • the sacrificial template is selected from one or more of sodium chloride or sucrose;
  • the particle size of the sacrificial template is 50 ⁇ m to 500 ⁇ m, such as 50 ⁇ m to 100 ⁇ m, 100 ⁇ m to 150 ⁇ m, 150 ⁇ m to 300 ⁇ m, 300 ⁇ m to 400 ⁇ m, or 400 ⁇ m to 500 ⁇ m;
  • the polymer is selected from one or more of polyurethane-based elastomers, polydimethylsiloxane-based elastomers, and polyolefin-based elastomers;
  • the organic solvent is selected from one or more of dimethylformamide, toluene and ethyl acetate.
  • feature 1) also includes at least one of the following technical features:
  • the conductive carbon black is spherical nano-scale conductive carbon black particles with a particle size of 20-100 nm;
  • the carbon nanotube has a diameter of 3 to 80 nm and a length of 5 to 30 ⁇ m;
  • the graphene sheet has a sheet diameter of ⁇ 10 ⁇ m, and the number of layers is 1-20.
  • the second aspect of the present invention provides the preparation method of the above-mentioned porous conductive paste, according to the composition ratio of the porous conductive paste, the conductive carbon material, the sacrificial template and the polymer carrier are mixed to obtain the porous conductive paste material.
  • the mixed solid obtained in step 1) is mixed with the polymer carrier to obtain the porous conductive paste.
  • the third aspect of the present invention provides the use of the above porous conductive paste for preparing flexible piezoresistive sensors.
  • a fourth aspect of the present invention provides a method for preparing a porous conductive structure sensing layer of a flexible piezoresistive sensor, which includes the following steps:
  • the sensing layer is prepared by printing or printing the above porous conductive paste, and then cured;
  • step 2) The sensor layer obtained in step 1) is immersed in water, and the sacrificial template is removed by dissolution to obtain the porous conductive structure sensor layer.
  • the method further includes: evaporating the solution dissolving the sacrificial template in step 2) to obtain the sacrificial template again.
  • the fifth aspect of the present invention provides a porous conductive structure sensing layer, which is obtained by using the above preparation method.
  • a sixth aspect of the present invention provides a method for preparing a flexible piezoresistive sensor, which includes the following steps:
  • the sensing layer is prepared by printing or printing the above porous conductive paste, and then cured;
  • step 2) The device obtained in step 2) is immersed in water, and the sacrificial template is removed by dissolution to obtain the flexible piezoresistive sensor.
  • the method further includes: evaporating the solution dissolving the sacrificial template in step 3) to obtain the sacrificial template again.
  • the present invention has the following advantages:
  • the invention uses a sacrificial template with adjustable particle size to prepare porous conductive paste, which greatly increases the number of nanopores or micropores after the conductive paste is formed into a film.
  • the invention adopts conductive carbon material, which can cooperate with high-density micro-pore structure to improve the sensitivity of the flexible piezoresistive sensor and greatly reduce the power consumption of the sensor.
  • the adjustable size of the hole size is helpful to adjust the sensitivity interval, which can meet different practical applications.
  • the porous conductive paste can be printed to ensure an efficient and low-cost preparation process. At the same time, the porous conductive paste with adjustable viscosity provides a variety of options for device design and processing.
  • FIG. 1 is a scanning electron micrograph of the microstructure of the porous conductive paste of Example 1 after curing and removing the sacrificial template.
  • FIG. 2 is a curve of pressure-resistance change of the flexible piezoresistive sensor of Example 1.
  • FIG. 3 is a graph of the test signal when the finger of the flexible piezoresistive sensor of Embodiment 3 is lightly pressed.
  • Example 4 is the experimental test data of the flexible piezoresistive sensor of Example 4 at ⁇ 800kPa and a fixed frequency.
  • Example 5 is the fatigue test data of the flexible piezoresistive sensor of Example 5 under a pressure of ⁇ 150kPa.
  • Example 6 is the cyclic test data of the flexible piezoresistive sensor of Example 6 at a pressure of about ⁇ 600 kPa.
  • Part 1 Mix and stir the ball-milled sodium chloride particles and carbon black particles at a mass ratio of 81:4;
  • Part 2 Dissolve thermoplastic polyurethane elastomer rubber particles (Elastollan 35A, BASF, Germany) to dimethylformamide In the solvent (the mass ratio of the thermoplastic polyurethane elastomer rubber particles to the dimethylformamide solvent is 1:2), stir and mix evenly under closed conditions and place it for more than 24h; put the first part and the second part at a mass ratio of 85:15 Stir and mix with planets to obtain a porous conductive paste for preparing flexible piezoresistive sensors.
  • the mass ratio of the thermoplastic polyurethane elastomer rubber particles to the dimethylformamide solvent is 1:2
  • the electrode can be formed to be flexible Tensile flexible stress sensor.
  • a flexible piezoresistive sensor is prepared by coating, 3D printing or screen printing method, and the preparation method is as follows:
  • 3D printing or screen printing devices can be customized in size and shape.
  • the above-mentioned flexible elastic substrate adopts thermoplastic polyurethane elastomer rubber particles, supplemented with an organic solvent to adjust the viscoelasticity.
  • 80% micron silver flakes are blended into a polymer consistent with the substrate, and the viscosity is adjusted with an organic solvent.
  • the above-mentioned sensing layer is composed of 6 layers of "bow" shape sensing materials, adjacent layers are staggered to form a network structure, and the total thickness of the sensing layer is about 2 mm.
  • Fig. 2 is a pressure-resistance relationship curve of a flexible piezoresistive sensor obtained by the above preparation method.
  • the sensor sensitivity is 5.54kpa -1 .
  • the sensor can measure a pressure of about 800kPa.
  • Part 1 Mix sodium chloride with a particle size of approximately 400 ⁇ m and conductive carbon black with a particle size of 20 to 100 nm at a mass ratio of 75:2 and stir them evenly;
  • Part 2 Mix polydimethylsiloxane elastomer (Sylgard 184) , Dow Corning) Dissolve in toluene solvent (the mass ratio of polydimethylsiloxane elastomer to toluene solvent is 1:2.5), stir and mix evenly under closed conditions and place for more than 24h; press the first part and the second part The mass ratio of 77:23 is evenly mixed with planetary stirring to obtain a porous conductive paste for preparing flexible piezoresistive sensors.
  • the flexible piezoresistive sensor is prepared according to the method of Example 2, and its response graph under light finger pressure (non-fixed frequency) is shown in FIG. 3.
  • Part 1 Mix sodium chloride and carbon nanotubes with a particle size of about 50 ⁇ m and carbon nanotubes (3 ⁇ 80nm, length 5 ⁇ 30 ⁇ m) according to a mass ratio of 82:4 and stir them uniformly , TPE, SBS) dissolved in ethyl acetate solvent (the mass ratio of polyolefin elastomer to ethyl acetate solvent is 1:2.2), stirred and mixed even under closed conditions and placed for more than 24h to obtain a flexible piezoresistive Conductive paste of the sensor.
  • the first part and the second part are uniformly mixed by planetary stirring at a mass ratio of 86:14 to obtain a porous conductive paste for preparing a flexible piezoresistive sensor.
  • the flexible piezoresistive sensor is prepared according to the method of Example 2, and the experimental test data at a load of 50 N ( ⁇ 800 kPa) and a fixed frequency is shown in FIG. 4.
  • Part 1 Mix sucrose with a diameter of about 300 ⁇ m and carbon nanotubes (3 ⁇ 80nm, length 5 ⁇ 30 ⁇ m) according to the mass ratio of 77:3 and stir them evenly;
  • Part 2 Mix the thermoplastic polyurethane elastomer rubber particles (Elastollan 35A, Germany BASF) dissolved in toluene solvent (the mass ratio of thermoplastic polyurethane elastomer rubber particles to toluene solvent is 1:2.7), stirred and mixed even under closed conditions and placed for more than 24h, to obtain porous conductive for the preparation of flexible piezoresistive sensors Slurry.
  • the first part and the second part are mixed and mixed evenly with a planetary mass ratio of 80:20 to obtain a porous conductive paste for preparing a flexible piezoresistive sensor.
  • the flexible piezoresistive sensor is prepared according to the method of Example 2, and the fatigue test data of more than 10,000 times under a load of 9.6 N ( ⁇ 150 kPa) is shown in FIG. 5.
  • the first part Mixing about 150 ⁇ m sucrose and graphene flakes (flake diameter ⁇ 10 ⁇ m, layer number is 1-20 layers) according to the mass ratio of 85:5 and stirring evenly; the second part: dimethicone Elastomers (Sylgard 184, Dow Corning) are dissolved in ethyl acetate solvent (the mass ratio of polydimethylsiloxane elastomer to ethyl acetate solvent is 1:2.4), stirred and mixed evenly under closed conditions and placed for 24h In the above, a porous conductive paste for preparing a flexible piezoresistive sensor is obtained.
  • the first part and the second part are uniformly mixed by planetary stirring at a mass ratio of 90:10 to obtain a porous conductive paste for preparing a flexible piezoresistive sensor.
  • the flexible piezoresistive sensor is prepared according to the method of Example 2, and the cycle test data at a pressure of about 600 kPa is shown in FIG. 6.
  • the first part mixing about 500 ⁇ m sucrose and graphene sheet (sheet diameter ⁇ 10 ⁇ m, the number of layers is 1 to 20 layers) according to the mass ratio of 75:3 and stirring;
  • the second part the polyolefin elastomer (such as SEBS, TPE, SBS) dissolved in dimethylformamide solvent (the mass ratio of polyolefin elastomer to dimethylformamide solvent is 1:3), stirred and mixed even in a closed condition and placed for more than 24h, obtained It is used to prepare porous conductive paste for flexible piezoresistive sensors.
  • the first part and the second part are uniformly mixed by planetary stirring at a mass ratio of 78:22 to obtain a porous conductive paste for preparing a flexible piezoresistive sensor.
  • the flexible piezoresistive sensor is prepared according to the method of Example 2, and its performance data are the same as those in FIGS. 3 and 5.

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Abstract

提供一种用于制备柔性压阻式传感器的多孔导电浆料及其制备方法和应用。该多孔导电浆料包括导电碳材料、牺牲性模板和高分子聚合物载体，高分子聚合物载体包括高分子聚合物和有机溶剂，高分子聚合物与有机溶剂的质量比为1：2～1：3，以导电碳材料、牺牲性模板和高分子聚合物总质量计，导电碳材料质量百分比为2％～5％，牺牲性模板质量百分比为75％～85％，高分子聚合物质量百分比为10％～23％。利用粒径可调的牺牲性模板制备多孔导电浆料，可极大的增加导电浆料成膜后的纳米孔或微米孔数量。在应力作用下，孔周围的导电颗粒相互接触，有效降低材料的电导率，从而与导电颗粒协同提升柔性压阻式传感器的灵敏度。

Description

一种用于制备柔性压阻式传感器的多孔导电浆料及其制备方法和应用 技术领域
本发明涉及一种压阻式传感器使用的感应材料及其制备方法和应用，尤其涉及一种用于制备柔性压阻式传感器的多孔导电浆料及其制备方法和应用。
背景技术
柔性压阻式传感器是可穿戴设备、机器人电子皮肤及植入式器件的关键器件之一。以硅材料为代表的传统半导体器件由于加工工艺复杂、设备投入成本高、环境污染大以及不具备柔性等局限，限制其在上述领域的应用。相较光刻技术,印刷技术可以在柔性基底上制备电子器件，且具有加工工艺简单、设备成本低等优点。如此,基于有机半导体材料和纳米功能材料等的印刷电子在近年得到迅猛发展。
基于压阻效应的传感器件具有灵敏度高、结构简单、信号易读取、受噪声影响小等优点。压阻传感器导电物质之间接触电阻的变化与施加压力的平方根成正比。通常，为了提升压阻传感器的灵敏性,需要采用较高电阻的压阻材料，以高功耗为代价。另一种有效的举措则是在压阻材料中创造更多的微观孔状结构。然而，目前报导的制备微观孔状结构的方法实施难度大，且效果不明显。因此，开发易制备、孔径可控的高电导多孔印刷浆料，并将这种浆料直接印刷在任意电极上，实现柔性甚至可拉伸的压力传感器件，具有重要的应用价值。
在CN103528722中，通过在纺织品表面印刷导电墨的支撑件，构成柔性压力传感器。特征在于，所述支撑件是柔软的、可伸展的和有弹性的，并且在所述支撑件上印刷可伸展和有弹性的导电墨或膏的多条主迹线。该工艺主要是利用导电油墨使织物表面构成压阻压力器件，印刷浆料上并无太多突破，传感器性能上主要受织物材制的限制。在CN101586992中，公开了一种公开了一种具有纳米SiC薄膜的压力传感器的制备方法，并采用丝网印刷、烧结处理制备纳米SiC薄膜。这类薄膜传感器主要是利用了后端电路的设计来提高灵敏度，且受力范围较小，器件不具备拉伸性。
发明内容
鉴于以上所述现有技术的缺点，本发明的目的在于提供一种用于制备柔性压阻式传感器的多孔导电浆料及其制备方法和应用。所述多孔导电浆料包括导电碳材料、牺牲性模板和高分子聚合物载体。本发明利用粒径可调的牺牲性模板制备多孔导电浆料，可极大的增加导电浆料成膜后的纳米孔或微米孔数量。在应力作用下，孔周围的导电颗粒相互接触，有效降低 材料的电导率，从而与导电颗粒协同提升柔性压阻式传感器的灵敏度。尺寸可调节的孔径大小有利于调整灵敏度区间，可满足不同实际应用。所述多孔导电浆料可印刷，为低成本、高效率的传感器制备工艺提供了保证。同时，粘度可调节的多孔导电浆料为器件的设计和加工提供多样性选择。
为实现上述目的及其他相关目的，本发明是通过以下技术方案实现的：
本发明第一方面提供一种用于制备柔性压阻式传感器的多孔导电浆料，包括导电碳材料、牺牲性模板和高分子聚合物载体，所述高分子聚合物载体包括高分子聚合物和有机溶剂，所述高分子聚合物与所述有机溶剂的质量比为1：2～1：3，如1：2～1：2.2、1：2.2～1：2.4、1：2.4～1：2.5、1：2.5～1：2.7或1：2.7～1：3，以导电碳材料、牺牲性模板和高分子聚合物总质量计，所述导电碳材料的质量百分比为2％～5％，如，2％～3％、3％～4％或4％～5％，所述牺牲性模板的质量百分比为75％～85％，如75％～77％、77％～81％、81％～82％或82％～85％，所述高分子聚合物的质量百分比为10％～23％，如10％～14％、14％～15％、15％～20％、20％～22％或22％～23％。
所述多孔导电浆料的粘度可由有机溶剂调节，以满足器件印刷或打印制备的需求。
优选地，还包括如下技术特征中的至少一项：
1)所述导电碳材料选自导电炭黑、碳纳米管和石墨烯片中的一种或多种；
2)所述牺牲性模版选自氯化钠或蔗糖中的一种或多种；
3)所述牺牲性模版的粒径为50μm～500μm，如50μm～100μm、100μm～150μm、150μm～300μm、300μm～400μm或400μm～500μm；
4)所述高分子聚合物选自聚氨酯类弹性体、聚二甲基硅氧烷类弹性体、聚烯烃类弹性体中的一种或多种；
5)所述有机溶剂选自二甲基甲酰胺、甲苯和乙酸乙酯中的一种或多种。
更优选地，特征1)中，还包括如下技术特征中的至少一项：
1)所述导电炭黑为球型纳米级导电炭黑粒子，粒径为20～100nm；
2)所述碳纳米管的直径为3～80nm,长度为5～30μm；
3)所述石墨烯片的片径<10μm，层数为1～20层。
本发明第二方面提供上述多孔导电浆料的制备方法，按照多孔导电浆料的组成配比，将所述导电碳材料、牺牲性模板和高分子聚合物载体混合，即得到所述多孔导电浆料。
优选地，包括如下步骤：
1)按照多孔导电浆料的组成配比，将所述导电碳材料与牺牲性模版混合，得到混合固体；
2)按照多孔导电浆料的组成配比，将步骤1)得到的混合固体与所述高分子聚合物载体混合，即得到所述多孔导电浆料。
本发明第三方面提供上述多孔导电浆料的用途，用于制备柔性压阻式传感器。
本发明第四方面提供一种柔性压阻式传感器的多孔导电结构传感层的制备方法，包括如下步骤：
1)将上述多孔导电浆料通过印刷或打印方式制备传感层，然后固化；
2)将步骤1)得到的传感层浸入水中，通过溶解脱除牺牲性模板，即得到所述多孔导电结构传感层。
优选地，还包括：将步骤2)中溶解牺牲性模板的溶液蒸发，重新得到牺牲性模板。
本发明第五方面提供一种多孔导电结构传感层，采用上述制备方法获得。
本发明第六方面提供一种柔性压阻式传感器的制备方法，包括如下步骤：
1)在柔性衬底上打印或印刷导电电极；
2)在导电电极上，将上述多孔导电浆料通过印刷或打印方式制备传感层，然后固化；
3)将步骤2)得到的器件浸入水中，通过溶解脱除牺牲性模板，即得到所述柔性压阻式传感器。
优选地，还包括：将步骤3)中溶解牺牲性模板的溶液蒸发，重新得到牺牲性模板。
与现有技术相比，本发明具有如下优点：
本发明利用粒径可调的牺牲性模板制备多孔导电浆料，极大程度增加导电浆料成膜后的纳米孔或微米孔的数量。本发明采用导电碳材料，可与高密度的微观孔状结构协同提高柔性压阻式传感器的灵敏度，并大幅度降低传感器功耗。尺寸可调节的孔大小有利于调整灵敏度区间，可满足不同实际应用。所述多孔导电浆料可印刷，保证高效、低成本的制备工艺。同时，粘度可调节的多孔导电浆料为器件的设计和加工提供多样性选择。
附图说明
图1为实施例1的多孔导电浆料在固化并脱除牺牲性模板后的微观结构扫描电镜照片。
图2为实施例1的柔性压阻式传感器压强-电阻变化关系曲线。
图3为实施例3的柔性压阻式传感器的手指轻按测试信号图线。
图4为实施例4的柔性压阻式传感器在～800kPa和固定频率下的实验测试数据。
图5为实施例5的柔性压阻式传感器在～150kPa压力下的疲劳测试数据。
图6为为实施例6的柔性压阻式传感器在约～600kPa压力的循环测试数据。
具体实施方式
以下通过特定的具体实例说明本发明的技术方案。应理解，本发明提到的一个或多个方法步骤并不排斥在所述组合步骤前后还存在其他方法步骤，或在这些明确提到的步骤之间还可以插入其他方法步骤；还应理解，这些实施例仅用于说明本发明而不用于限制本发明的范围。而且，除非另有说明，各方法步骤的编号仅为鉴别各方法步骤的便利工具，而非为限制各方法步骤的排列次序，或限定本发明可实施的范围，其相对关系的改变或调整，在无实质变更技术内容的情况下，当亦视为本发明可实施的范畴。
实施例1
类炉黑法制备粒径为20～100nm导电炭黑粒子；将工业氯化钠颗粒放入球磨机中以500r/min的转速球磨20min，球料比约为1:1，获得直径约为100μm的氯化钠颗粒。第一部分：将球磨后的氯化钠颗粒与炭黑粒子按质量比81:4混合搅拌均匀；第二部分：将热塑性聚氨酯弹性体橡胶颗粒(Elastollan 35A,德国BASF)溶解至二甲基甲酰胺溶剂中(热塑性聚氨酯弹性体橡胶颗粒与二甲基甲酰胺溶剂的质量比为1:2)，密闭条件下搅拌混合均匀并放置24h以上；将第一部分和第二部分按85:15的质量比用行星搅拌混合均匀，获得用于制备柔性压阻式传感器的多孔导电浆料。
将上述多孔导电浆料打印并固化后，浸至于水中进行反复脱盐(氯化钠)处理，脱除牺牲性模板后的微观结构扫描电镜照片如图1所示，接入电极即可构成柔性可拉伸柔性应力传感器。
实施例2
基于上述多孔导电浆料，采用涂布、3D打印或丝网印刷方法制备柔性压阻式传感器，其制备方法如下：
利用涂布、3D打印或丝网印刷工艺，在任意平面基板上涂布、打印或印刷设计好大小与形状的柔弹性衬底；
在柔弹性衬底上打印或印刷设计好的导电电极，并在导电电极上，采用实施例1得到的多孔导电浆料打印或印刷单层或多层重叠的任意形状的传感层，固化后将整个器件浸至于水中进行脱盐处理。3D打印或丝网印刷器件大小与形状均可定制化设计。
上述柔弹性衬底采用热塑性聚氨酯弹性体橡胶颗粒，辅以有机溶剂调节粘弹性。上述导电电极采用在与衬底一致的聚合物中掺入80％微米银片，并用有机溶剂调节粘度。上述传感层由6层“弓”字形传感材料组成，相邻层交错设置，形成网状结构，传感层总厚度约有2mm。
图2为采用上述制备方法获得的柔性压阻式传感器的压强-电阻变化关系曲线。在20kPa范围内，传感器灵敏度为5.54kpa -1。同时，该传感器可测量约800kPa的压力。
实施例3
第一部分：将约400μm粒径的氯化钠与20～100nm粒径的导电炭黑按质量比75：2混合搅拌均匀；第二部分：将聚二甲基硅氧烷类弹性体(Sylgard 184,道康宁)溶解至甲苯溶剂中(聚二甲基硅氧烷类弹性体与甲苯溶剂的质量比为1:2.5)，密闭条件下搅拌混合均匀并放置24h以上；将第一部分和第二部分按77:23的质量比用行星搅拌混合均匀，获得用于制备柔性压阻式传感器的多孔导电浆料。
按照实施例2的方法制备柔性压阻式传感器，其在手指轻微按压下(非固定频率)的响应图线如图3所示。
实施例4
第一部分：将约50μm粒径的氯化钠与碳纳米管(3～80nm,长度为5～30μm)按质量比82:4混合搅拌均匀；第二部分：将聚烯烃类弹性体(如SEBS，TPE，SBS)溶解至乙酸乙酯溶剂中(聚烯烃类弹性体与乙酸乙酯溶剂的质量比为1:2.2)，密闭条件下搅拌混合均匀并放置24h以上，获得用于制备柔性压阻式传感器的多孔导电浆料。将第一部分和第二部分按86:14的质量比用行星搅拌混合均匀，获得用于制备柔性压阻式传感器的多孔导电浆料。
按照实施例2的方法制备柔性压阻式传感器，其在载荷50N(～800kPa)和固定频率下的实验测试数据如图4所示。
实施例5
第一部分：将约300μm粒径的蔗糖与碳纳米管(3～80nm,长度为5～30μm)按质量比77:3混合搅拌均匀；第二部分：将热塑性聚氨酯弹性体橡胶颗粒(Elastollan 35A,德国BASF)溶解至甲苯溶剂中(热塑性聚氨酯弹性体橡胶颗粒与甲苯溶剂的质量比为1:2.7)，密闭条件下搅拌混合均匀并放置24h以上，获得用于制备柔性压阻式传感器的多孔导电浆料。将第一部分和第二部分按80:20的质量比用行星搅拌混合均匀，获得用于制备柔性压阻式传感器的多孔导电浆料。
按照实施例2的方法制备柔性压阻式传感器，其在9.6N(～150kPa)载荷下大于10000次的疲劳测试数据如图5所示。
实施例6
第一部分：将约150μm粒径蔗糖的与石墨烯片(片径<10μm，层数为1～20层)按质量比85:5混合搅拌均匀；第二部分：将聚二甲基硅氧烷类弹性体(Sylgard 184,道康宁)溶解至乙酸乙酯溶剂中(聚二甲基硅氧烷类弹性体与乙酸乙酯溶剂的质量比为1:2.4)，密闭条件下搅拌混合均匀并放置24h以上，获得用于制备柔性压阻式传感器的多孔导电浆料。将第一部分和第二部分按90:10的质量比用行星搅拌混合均匀，获得用于制备柔性压阻式传感器的多孔导电浆料。
按照实施例2的方法制备柔性压阻式传感器，其在约600kPa压力的循环测试数据如图6所示。
实施例7
第一部分：将约500μm粒径蔗糖的与石墨烯片(片径<10μm，层数为1～20层)按质量比75：3混合搅拌均匀；第二部分：将聚烯烃类弹性体(如SEBS，TPE，SBS)溶解至二甲基甲酰胺溶剂中(聚烯烃类弹性体与二甲基甲酰胺溶剂的质量比为1:3)，密闭条件下搅拌混合均匀并放置24h以上，获得用于制备柔性压阻式传感器的多孔导电浆料。将第一部分和第二部分按78:22的质量比用行星搅拌混合均匀，获得用于制备柔性压阻式传感器的多孔导电浆料。
按照实施例2的方法制备柔性压阻式传感器，其性能数据与图3和图5相同。
以上所述，仅为本发明的较佳实施例，并非对本发明任何形式上和实质上的限制，应当指出，对于本技术领域的普通技术人员，在不脱离本发明方法的前提下，还将可以做出若干改进和补充，这些改进和补充也应视为本发明的保护范围。凡熟悉本专业的技术人员，在不脱离本发明的精神和范围的情况下，当可利用以上所揭示的技术内容而做出的些许更动、修饰与演变的等同变化，均为本发明的等效实施例；同时，凡依据本发明的实质技术对上述实施例所作的任何等同变化的更动、修饰与演变，均仍属于本发明的技术方案的范围内。

Claims (11)

  1. 一种用于制备柔性压阻式传感器的多孔导电浆料，其特征在于，包括导电碳材料、牺牲性模板和高分子聚合物载体，所述高分子聚合物载体包括高分子聚合物和有机溶剂，所述高分子聚合物与所述有机溶剂的质量比为1：2～1：3，以导电碳材料、牺牲性模板和高分子聚合物总质量计，所述导电碳材料的质量百分比为2％～5％，所述牺牲性模板的质量百分比为75％～85％，所述高分子聚合物的质量百分比为10％～23％。
  2. 如权利要求1所述的多孔导电浆料，其特征在于，还包括如下技术特征中的至少一项：
    1)所述导电碳材料选自导电炭黑、碳纳米管和石墨烯片中的一种或多种；
    2)所述牺牲性模版选自氯化钠或蔗糖中的一种或多种；
    3)所述牺牲性模版的粒径为50μm～500μm；
    4)所述高分子聚合物选自聚氨酯类弹性体、聚二甲基硅氧烷类弹性体、聚烯烃类弹性体中的一种或多种；
    5)所述有机溶剂选自二甲基甲酰胺、甲苯和乙酸乙酯中的一种或多种。
  3. 如权利要求2所述的多孔导电浆料，其特征在于，特征1)中，还包括如下技术特征中的至少一项：
    1)所述导电炭黑为球型纳米级导电炭黑粒子，粒径为20～100nm；
    2)所述碳纳米管的直径为3～80nm,长度为5～30μm；
    3)所述石墨烯片的片径<10μm，层数为1～20层。
  4. 如权利要求1至3任一项所述的多孔导电浆料的制备方法，其特征在于，按照多孔导电浆料的组成配比，将所述导电碳材料、牺牲性模板和高分子聚合物载体混合，即得到所述多孔导电浆料。
  5. 如权利要求4所述的多孔导电浆料的制备方法，其特征在于，包括如下步骤：
    1)按照多孔导电浆料的组成配比，将所述导电碳材料与牺牲性模版混合，得到混合固体；
    2)按照多孔导电浆料的组成配比，将步骤1)得到的混合固体与所述高分子聚合物载体混合，即得到所述多孔导电浆料。
  6. 如权利要求1至3任一项所述的多孔导电浆料的用途，其特征在于，用于制备柔性压阻式传感器。
  7. 一种柔性压阻式传感器的多孔导电结构传感层的制备方法，其特征在于，包括如下步骤：
    1)将权利要求1至3任一项所述的多孔导电浆料通过印刷或打印方式制备传感层，然后固化；
    2)将步骤1)得到的传感层浸入水中，通过溶解脱除牺牲性模板，即得到所述多孔导电 结构传感层。
  8. 如权利要求7所述的多孔导电结构传感层的制备方法，其特征在于，还包括：将步骤2)中溶解牺牲性模板的溶液蒸发，重新得到牺牲性模板。
  9. 一种多孔导电结构传感层，其特征在于，采用权利要求7或8任一项所述的制备方法获得。
  10. 一种柔性压阻式传感器的制备方法，其特征在于，包括如下步骤：
    1)在柔性衬底上打印或印刷导电电极；
    2)在导电电极上，将权利要求1至3任一项所述的多孔导电浆料通过印刷或打印方式制备传感层，然后固化；
    3)将步骤2)得到的器件浸入水中，通过溶解脱除牺牲性模板，即得到所述柔性压阻式传感器。
  11. 如权利要求10所述的柔性压阻式传感器的制备方法，其特征在于，还包括：将步骤3)中溶解牺牲性模板的溶液蒸发，重新得到牺牲性模板。
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