CN108760099A - Preparation process for high sensitivity voltage sensitive sensor - Google Patents

Abstract

The invention discloses a flexible pressure-sensitive sensor, which comprises an upper conductive electrode, a sensing medium layer, and a lower conductive electrode. After mixing vinylpyrrolidone, alkylphenol polyoxyethylene ether, polyethylene glycol p-isooctyl phenyl ether, bismuth isooctanoate, and toluene diisocyanate, the mixed solution is obtained by ultrasonic dispersion; the mixed solution is injected into the polyurethane foam body , and then immerse the polyurethane foam body injected with the mixed solution in the mixed solution; repeatedly squeeze the polyurethane foam body through step two; place the polyurethane foam body soaked in the mixed solution through step three in an oven for drying Dry. The invention is bendable, resistant to bending, can sense micro pressure, and still has high sensitivity under relatively high pressure, and is also convenient to design devices with various sensitivities and ranges. The comprehensive accuracy is less than 0.2% FS, and the reliability is high.

Description

Preparation process for high-sensitivity pressure-sensitive sensor

technical field

The invention relates to the technical field of sensors, in particular to a preparation process for a high-sensitivity pressure-sensitive sensor.

Background technique

Pressure sensors can be divided into piezoelectric sensors based on piezoelectric materials and piezoresistive sensors based on piezoresistive materials according to materials. Piezoelectric sensors made of piezoelectric ceramics, piezoelectric crystals, piezoelectric electrets, and organic piezoelectric films as sensitive elements generate transferable charges on the surface of the material when they are under pressure, and the voltage when the charges pass through the detection device Can directly reflect the size of the pressure. The piezoresistive sensor with alloy sensitive gate, semiconductor and other materials as sensitive elements deforms when it is under pressure, and the deformation causes the resistance of the sensitive element to change. By detecting the change in the resistance of the sensitive element through the Wheatstone bridge, the pressure applied to the pressure sensitive sensor can be detected. The amount of pressure on the sensor.

Existing pressure sensors are often not resistant to bending, and the sensitivity is not enough. The error of measuring pressure with the sensor of pressure-sensitive material will reach about 20%, and the measurement accuracy is poor. How to overcome the above technical problems and improve them has become an effort for those skilled in the art. direction.

Contents of the invention

The purpose of the present invention is to provide a preparation process for a high-sensitivity pressure-sensitive sensor. The high-sensitivity pressure-sensitive sensor obtained by this preparation process is bendable, resistant to bending, and can sense small pressures, while still having High sensitivity, good repeatability of detection accuracy, and easy to design devices with various sensitivities and ranges.

In order to achieve the above object, the technical solution adopted in the present invention is: a preparation process for a high-sensitivity pressure-sensitive sensor, the high-sensitivity pressure-sensitive sensor includes an upper conductive electrode, a sensing medium layer, and a lower conductive electrode. The upper conductive electrode and the lower conductive electrode are respectively connected to the upper surface and the lower surface of the sensing medium layer through the first conductive adhesive layer and the second conductive adhesive layer. The sensing medium layer includes a polyurethane foam body and is filled with polyurethane foam. The surface of the foam body and the induction coating layer in the pores, the induction coating layer is composed of the following components:

100 parts of silver nanowire aqueous dispersion,

3~5 parts of water-based acrylic resin,

20~30 parts of ethanol,

0.4~0.6 parts of polyvinylpyrrolidone,

Alkylphenol polyoxyethylene ether 0.2~0.5 parts,

Polyethylene glycol p-isooctyl phenyl ether 0.4~0.8 parts,

Bismuth isooctanoate 0.2~0.5 parts,

Toluene diisocyanate 0.1~0.3 parts;

The sensing medium layer is obtained through the following steps:

Step 1, 100 parts of silver nanowire aqueous dispersion, 3-5 parts of water-based acrylic resin, 20-30 parts of ethanol, 0.4-0.6 parts of polyvinylpyrrolidone, 0.2-0.5 parts of alkylphenol polyoxyethylene ether, polyethylene glycol After mixing 0.4-0.8 parts of alcohol p-isooctylphenyl ether, 0.2-0.5 parts of bismuth isooctanoate, and 0.1-0.3 parts of toluene diisocyanate, the mixture is obtained by ultrasonic dispersion;

Step 2, injecting the mixed solution into the polyurethane foam body, and then immersing the polyurethane foam body injected with the mixed solution into the mixed solution;

Step 3, extruding the polyurethane foam body after step 2;

Step 4. Place the polyurethane foam body soaked in the mixed solution after step 3 in an oven to dry, so as to obtain a polyurethane foam body with an induction coating layer on the surface and in the pores.

Further improvement technical scheme in above-mentioned technical scheme is as follows:

1. In the above scheme, the polyurethane foam body has a first through hole through the upper surface and the lower surface, and the upper conductive electrode has a branch electrode strip, one end of the branch electrode strip is electrically connected to the upper conductive electrode, and the other One end extends from the second through hole of the lower conductive electrode.

2. In the above solution, the branch electrode strips are located in the central area of the upper conductive electrode.

3. In the above solution, the upper conductive electrode and the lower conductive electrode are composed of a flexible base film and a silver nanowire coating coated on the surface of the flexible base film.

4. In the above solution, the flexible base film is a PET film or a TPU film.

5. In the above solution, several electrically connecting solder joints are provided on the lower surface of the lower conductive electrode.

6. In the above solution, the number of extrusions in the third step is at least 2 times.

7. In the above scheme, the second step is to immerse in the mixed solution for 2 to 5 minutes.

Due to the use of the above-mentioned technical solutions, the present invention has the following advantages and effects compared with the prior art:

The invention is used in the preparation process of the high-sensitivity pressure-sensitive sensor, and the high-sensitivity pressure-sensitive sensor can be bent, resists bending, can sense tiny pressure, and at the same time still has high sensitivity under relatively high pressure, and is also convenient to design various Sensitivity and range of devices, the comprehensive accuracy is less than 0.2% FS, high reliability, good durability; secondly, its induction coating layer contains 0.2~0.5 parts of bismuth isooctanoate, 0.1~0.3 parts of toluene diisocyanate, which is beneficial to improve the induction coating The adhesion between the coating and the polyurethane foam body ensures that the test data is stable and the test accuracy is repeatable through 10,000 cycle tests.

Description of drawings

Accompanying drawing 1 is the structural representation of the high-sensitivity pressure-sensitive sensor that the preparation process of the present invention obtains;

Accompanying drawing 2 is the partial structure diagram of accompanying drawing 1.

In the above drawings: 1. Upper conductive electrode; 2. Sensing medium layer; 21. Polyurethane foam body; 3. Lower conductive electrode; 4. First conductive adhesive layer; 5. Second conductive adhesive layer; 6 1. The first through hole; 7. The branch electrode strip; 8. The second through hole; 9. The electrical connection solder joint; 10. The flexible base film; 11. The silver nanowire coating.

Detailed ways

The present invention will be further described below in conjunction with embodiment:

Embodiments 1 to 4: A preparation process for a high-sensitivity pressure-sensitive sensor, the high-sensitivity pressure-sensitive sensor includes an upper conductive electrode 1, a sensing medium layer 2, and a lower conductive electrode 3, and the upper conductive electrode 1. The lower conductive electrode 3 is respectively connected to the upper surface and the lower surface of the sensing medium layer 2 through the first conductive adhesive layer 4 and the second conductive adhesive layer 5. The sensing medium layer 2 includes a polyurethane foam body 21 and The induction coating layer filled on the surface of the polyurethane foam body 21 and in the pores is composed of the following components, as shown in Table 1:

Table 1

The sensing medium layer 2 is obtained through the following steps:

Step 1, 100 parts of silver nanowire aqueous dispersion, 3-5 parts of water-based acrylic resin, 20-30 parts of ethanol, 0.4-0.6 parts of polyvinylpyrrolidone, 0.2-0.5 parts of alkylphenol polyoxyethylene ether, polyethylene glycol After mixing 0.4-0.8 parts of alcohol p-isooctylphenyl ether, 0.2-0.5 parts of bismuth isooctanoate, and 0.1-0.3 parts of toluene diisocyanate, the mixture is obtained by ultrasonic dispersion;

Step 2: inject the mixed liquid into the polyurethane foam body 21, then immerse the polyurethane foam body 21 injected with the mixed liquid into the mixed liquid, and let it stand for 2 to 5 minutes;

Step 3, repeatedly extruding the polyurethane foam body 21 after step 2;

Step 4: Place the polyurethane foam body 21 soaked in the mixed liquid after step 3 to dry in an oven, so as to obtain the polyurethane foam body 21 with an induction coating layer on the surface and in the pores.

When the preparation process of the present invention is used for the high-sensitivity pressure-sensitive sensor, the high-sensitivity pressure-sensitive sensor can be bent, resist bending, and can sense small pressure, and at the same time, it still has high sensitivity under relatively high pressure, and is also convenient for design Devices with various sensitivities and ranges have a comprehensive accuracy of less than 0.2% FS, high reliability and good durability; secondly, the inductive coating layer contains 0.2-0.5 parts of bismuth isooctanoate and 0.1-0.3 parts of toluene diisocyanate, which is beneficial to improve The adhesion between the coating layer and the polyurethane foam body is sensed, so as to ensure that the test data is stable and the repeatability of the test accuracy is good after passing 10,000 cycle tests.

The above-mentioned embodiments are only to illustrate the technical concept and characteristics of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and not to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention shall fall within the protection scope of the present invention.

Claims (8)

1. a kind of preparation process for high sensitivity voltage sensitive sensor, it is characterised in that：The high sensitivity voltage sensitive sensor Including upper conductive electrode（1）, sensing medium layer（2）, lower conductive electrode（3）, the upper conductive electrode（1）, lower conductive electrode（3） Respectively with sensing medium layer（2）Upper and lower surface passes through the first conductive adhesive layer（4）, the second conductive adhesive layer（5）Connection, The sensing medium layer（2）Including polyurethane foam ontology（21）Be filled in polyurethane foam ontology（21）In surface and hole Induction coat composition, the induction coat is composed of the following components：100 parts of nano silver wire aqueous dispersions, aqueous acrylamide 3 ~ 5 parts of acid resin, 20 ~ 30 parts of ethyl alcohol, 0.2 ~ 0.5 part of alkyl phenol polyoxyethylene ether, gather 0.4 ~ 0.6 part of polyvinylpyrrolidone Ethylene glycol is to 0.4 ~ 0.8 part of isooctyl phenyl ether, 0.2 ~ 0.5 part of isooctyl acid bismuth, 0.1 ~ 0.3 part of toluene di-isocyanate(TDI)；

The sensing medium layer（2）It is obtained by following steps：

Step 1: by 100 parts of nano silver wire aqueous dispersions, 3 ~ 5 parts of water-based acrylic resin, 20 ~ 30 parts of ethyl alcohol, polyvinyl pyrrole 0.4 ~ 0.6 part of alkanone, 0.2 ~ 0.5 part of alkyl phenol polyoxyethylene ether, polyethylene glycol are to 0.4 ~ 0.8 part of isooctyl phenyl ether, different pungent After 0.1 ~ 0.3 part of 0.2 ~ 0.5 part of sour bismuth, toluene di-isocyanate(TDI) mixing, disperseed to obtain mixed liquor by ultrasonic wave；

Step 2: the mixed liquor is injected polyurethane foam ontology（21）Polyurethane foam that is interior, then mixed liquor will being injected with Ontology（21）It immerses in mixed liquor；

Step 3: squeezing the polyurethane foam ontology Jing Guo step 2（21）；

Step 4: by the polyurethane foam ontology for being soaked with mixed liquor Jing Guo step 3（21）It is positioned in oven and dries, to Obtaining has the polyurethane foam ontology of induction coat in surface and hole（21）.

2. the preparation process according to claim 1 for high sensitivity voltage sensitive sensor, it is characterised in that：The poly- ammonia Ester foam ontology（21）It is provided with the first through hole of a perforation upper and lower surface（6）, the upper conductive electrode is with a branch Electrode strip（7）, this branch electrodes item（7）One end is electrically connected with upper conductive electrode, and the other end is to lower conductive electrode（3）Second Through-hole（8）Extend at place.

3. the preparation process according to claim 2 for high sensitivity voltage sensitive sensor, it is characterised in that：The branch Electrode strip（7）Positioned at the middle section of upper conductive electrode.

4. the preparation process according to claim 2 for high sensitivity voltage sensitive sensor, it is characterised in that：It is led on described Electrode（1）, lower conductive electrode（3）By flexible base film（10）With coated on flexible base film（10）The nano silver wire coating on surface （11）Composition.

5. the preparation process according to claim 4 for high sensitivity voltage sensitive sensor, it is characterised in that：The flexibility Basement membrane is PET film or TPU film.

6. the preparation process according to claim 1 for high sensitivity voltage sensitive sensor, it is characterised in that：It is led under described Electrode lower surface is provided with several and is electrically connected solder joint（9）.

7. the preparation process according to claim 1 for high sensitivity voltage sensitive sensor, it is characterised in that：The step Three extrusion passes at least 2 times.

8. the preparation process according to claim 1 for high sensitivity voltage sensitive sensor, it is characterised in that：The step It is quiet to 2 ~ 5 minutes in two immersion mixed liquors.