CN112229548A - Flexible sensor array - Google Patents
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- CN112229548A CN112229548A CN202011260486.4A CN202011260486A CN112229548A CN 112229548 A CN112229548 A CN 112229548A CN 202011260486 A CN202011260486 A CN 202011260486A CN 112229548 A CN112229548 A CN 112229548A
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- G—PHYSICS
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- G01L1/00—Measuring force or stress, in general
- G01L1/16—Measuring force or stress, in general using properties of piezoelectric devices
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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
- G01L9/08—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 piezoelectric devices, i.e. electric circuits therefor
Abstract
The invention discloses a flexible sensor array, which is sequentially provided with a first electrode array substrate, an insulating adhesive layer, a composite pressure-sensitive layer and a second electrode array substrate, wherein the first electrode array substrate and the second electrode array substrate respectively adopt the electrode arrays arranged on the flexible substrates to form a first electrode array and a second electrode array, and any point electrode of the first electrode array corresponds to one point electrode of the second electrode array one by one to serve as an electrode group. The invention can realize a large-area sensor array, the pressure-sensitive array and the electrode array have better connectivity, better adhesive force, smaller volume and higher preparation efficiency, and the process of repeatedly installing the pressure-sensitive layer is avoided.
Description
Technical Field
The invention relates to the technical field of flexible sensors, in particular to a flexible sensor array.
Background
With the improvement of technology and modernization level, the requirement of people on pressure monitoring is higher and higher, the pressure monitoring is not limited to the pressure monitoring of a regular rigid surface, the modes are also various, and the common rigid sensor can not meet the actual requirements of people. For example, people hope to realize real-time monitoring of physiological indexes such as heartbeat, pulse, blood pressure, respiration and the like through wearable, applicable and even implantable modes, and the products not only need to give consideration to accuracy and safety, but also need to consider the comfort of wearing the human body, can bear various daily actions of the human body, and even carry heavy-load movement without influencing the performance indexes of the sensor. The flexible pressure sensor is randomly bent or even folded, has small volume and thin thickness, is basically non-toxic and harmless as a flexible material, has good compatibility with a human body, and is widely researched and applied in the fields of medical equipment, intelligent robots, wearable equipment and the like.
Although flexible pressure sensor technology has advanced significantly in recent years, large area flexible array sensors have been less studied. In large-area integration application, a pressure-sensitive layer is generally prepared and then cut and installed according to application requirements in the prior art based on a coating process, so that the material utilization rate is low, the thickness is too large, and the cost is too high. And secondly, the efficiency is too low, large-area integration is realized, the repeated installation and manufacturing of a single sensor are only realized, and the method is not suitable for manufacturing large-area high-density flexible array sensors.
Therefore, it is necessary to provide a technical solution to solve the technical problems of the prior art.
Disclosure of Invention
In view of the above, it is necessary to provide a flexible pressure sensor array, so as to reduce the volume of the flexible pressure sensor array, improve the efficiency of large-area integrated manufacturing, and improve the material utilization rate.
In order to solve the technical problems in the prior art, the technical scheme of the invention is as follows:
a flexible sensor array is sequentially provided with a first electrode array substrate, an insulating adhesive layer, a composite pressure-sensitive layer and a second electrode array substrate, wherein the first electrode array substrate and the second electrode array substrate respectively adopt an electrode array arranged on a flexible substrate to form a first electrode array and a second electrode array, and any point electrode of the first electrode array and a point electrode of the second electrode array correspond to each other one by one to serve as an electrode group;
the composite pressure-sensitive layer is a pressure-sensitive layer lattice arranged between the first electrode array and the second electrode array, and any point unit in the pressure-sensitive layer lattice completely covers and is pressed between the corresponding electrode groups; the pressure-sensitive layer lattice is formed by directly printing an uncured pressure-sensitive composite material on the surface of the first electrode array/the second electrode array in a screen printing mode and curing;
the insulating glue layer is used for bonding the first electrode array substrate and the second electrode array substrate.
In a preferred embodiment, the first electrode array substrate and the second electrode array substrate are further provided with lead terminals electrically connected to the respective dot electrodes for connection to an external circuit.
As a preferred technical solution, the first electrode array substrate and the second electrode array substrate respectively form a first electrode array and a second electrode array by printing silver paste on a flexible substrate.
As a preferable technical solution, the flexible substrate is made of polyester PET or polyimide PI.
As a preferable technical scheme, the composite pressure-sensitive layer is prepared from a pressure-sensitive composite material, and the pressure-sensitive composite material comprises carbon black, silicon rubber, a silane coupling agent and nano SIO2And naphtha.
According to a preferable technical scheme, the carbon black accounts for 2-10% of the mass of the silicon rubber, the silane coupling agent accounts for 2-5% of the total mass of the ingredients, the nano SIO2 accounts for 2-10% of the total mass of the ingredients, and the balance is naphtha; the sum of the above components is 100%.
Preferably, the proportion of the carbon black is 6% of the mass of the silicone rubber.
As a preferable technical scheme, the carbon black adopts lion ECP600JD or Kabet BP 2000.
As a preferable technical scheme, the silicone rubber adopts Dow Corning 184 or 107 type silicone rubber.
As a preferable technical scheme, the silane coupling agent is a silane coupling agent KH-560.
Compared with the prior art, the invention realizes the manufacture of a large-area sensor array by utilizing the printing process on the basis of improving the formula of the composite material, thoroughly changes the prior process flow of repeatedly installing the flexible pressure sensor based on a coating mode, has better connectivity with the electrode array, better adhesive force, smaller volume and higher preparation efficiency, avoids the repeated installation process of the traditional process, and has simple process and high material utilization rate.
The large-area sensing array has a simple structure and a small thickness, and the electrode arrays are communicated through the public row lines and the public column lines, so that the complexity of a signal acquisition circuit is reduced. Meanwhile, the interference among array points is less, the density area can be changed at will, the cost is low, and the application range of the flexible sensor array is greatly improved.
Drawings
FIG. 1 is a block diagram of a flexible sensor array of the present invention.
FIG. 2 is a flow chart of a process for preparing a pressure sensitive composite material according to the present invention.
FIG. 3 is a graph of the effect of carbon black content on the conductive properties of a composite.
FIG. 4 is a piezoresistive curve at a carbon black concentration of 6%.
FIG. 5 illustrates a process for manufacturing a flexible sensor array according to the present invention.
Figure 6 is a piezoresistive characteristic of a flexible sensor array according to the invention.
The following specific embodiments will further illustrate the invention in conjunction with the above-described figures.
Detailed Description
The technical solution provided by the present invention will be further explained with reference to the accompanying drawings.
In the flexible sensor in the prior art, the preparation of the pressure-sensitive film is mostly realized by adopting the modes of glue homogenizing and the like, and after the pressure-sensitive film is cured and formed, the pressure-sensitive layer with the required shape is obtained from the film.
Referring to fig. 1, a structural block diagram of a flexible sensor array provided by the present invention is shown, in which a "sandwich" type sandwich structure is adopted, and a first electrode array substrate, an insulating adhesive layer, a composite pressure sensitive layer, and a second electrode array substrate are sequentially disposed, wherein the first electrode array substrate and the second electrode array substrate respectively form a first electrode array and a second electrode array by disposing electrode arrays on a flexible substrate, and any point electrode of the first electrode array corresponds to a point electrode of the second electrode array one by one to serve as an electrode group;
the composite pressure-sensitive layer is a pressure-sensitive layer lattice arranged between the first electrode array and the second electrode array, and any point unit in the pressure-sensitive layer lattice completely covers and is pressed between the corresponding electrode groups; the pressure-sensitive layer lattice is formed by directly printing an uncured pressure-sensitive composite material on the surface of the first electrode array/the second electrode array in a screen printing mode and curing;
the insulating glue layer is used for bonding the first electrode array substrate and the second electrode array substrate.
Meanwhile, the first electrode array substrate and the second electrode array substrate are also provided with lead terminals which are electrically connected with the point electrodes and used for being connected with an external circuit.
In the technical scheme, the manufacturing of the flexible sensor is completed by pressing the pressure-sensitive layer between the upper electrode and the lower electrode, wherein any electrode array substrate is used as a bottom plate, the composite pressure-sensitive layer is prepared on each point electrode in a screen printing mode, and then the other electrode array substrate is arranged on the composite pressure-sensitive layer, so that the upper electrode and the lower electrode are completely pressed on the composite pressure-sensitive layer. The sensor array is a public row line structure, a terminal is independently led out from each point electrode, and through the circulation gating of the row line and the column line, the collection of the sensor array signals is conveniently completed, the signals of all the points in the dot matrix are mutually independent, the signal value of each point is only related to the actual strength, the testing of the actual pressure value of the flexible surface is facilitated, and the actual stress condition can be better obtained by means of the position relation of all the electrode points.
In the research of the applicant, the single-component room temperature vulcanized silicone rubber widely used for the pressure-sensitive material at present has the defects that the surface drying time is too short, the contact area of the composite material and air is increased if the composite material is directly printed, the friction between a scraper and a screen printing plate can cause heating, and the factors can accelerate the curing of the silicone rubber to cause the phenomenon of screen blocking.
Therefore, how to prepare the pressure-sensitive composite material with high performance and low cost and suitable for screen printing is the key, and the invention provides a formula of the pressure-sensitive composite material and a preparation process thereof on the basis of carrying out a large number of theories and experimental analysis.
Referring to fig. 2, a flow diagram of a method for preparing a pressure-sensitive composite material of the present invention is shown, comprising the steps of:
step S11: selecting ingredients; the silicon rubber comprises carbon black, silicon rubber, a silane coupling agent, nano SIO2 and naphtha, wherein the proportion of the carbon black is 2-10% of the mass of the silicon rubber, the proportion of the silane coupling agent is 2-5% of the total mass of ingredients, the proportion of the nano SIO2 is 2-10% of the total mass of ingredients, and the balance is the naphtha;
step S12: mixing materials; firstly, adding carbon black, a silane coupling agent and nano SIO2 into naphtha, physically stirring for 5-30min, and then ultrasonically dispersing for 30-50 min; then adding the silicon rubber into the mixed solution, and physically stirring for 5-8 h; the ultrasonic dispersion process is adopted, which is helpful for the conductive carbon black to be completely dispersed in the naphtha.
Step S13: drying; and putting the mixed solution into a vacuum drying oven, and removing the non-volatile organic solvent to form a viscous solution.
In the technical scheme, the two-component room temperature vulcanized silicone rubber and naphtha are selected to prepare the composite material for printing, and experimental research shows that the two-component room temperature vulcanized silicone rubber, such as Dow Corning 184, 107 silicone rubber and the like, still has the operable time of about 2 hours even after the curing cross-linking agent is added; the solvent volatilization speed is too fast or too slow, which can bring adverse effect to the curing and molding of the final composite material. Experiments show that the naphtha volatilization speed is moderate, the naphtha volatilization speed is also very suitable for a printing system, and a proper amount of naphtha is added to reduce the viscosity of the composite material; however, excessive amounts of naphtha can affect the final shrinkage of the silicone rubber. Preferably, the amount of naphtha used is more than 2 times the mass of the silicone rubber, and naphtha is most advantageous for the uniform dispersion of carbon black and the modifying material.
Furthermore, the carbon black is selected as the conductive filler, the carbon black is widely available in the natural world, the conductive performance is excellent, the performance is stable, the carbon black is not easy to be oxidized, and the carbon black is easy to disperse in the silicone rubber compared with metal particles. In a preferred embodiment, the carbon black is selected from conductive carbon blacks having high structure and high specific surface area, such as lion ECP600JD or Cabot BP 2000.
The coupling agent is an organic compound with a special structure, and the molecule has two groups with two characteristics. One group can act with inorganic filler, the other group can act with organic molecule, can make filler and organic matter cross-link with chemical bond, improve compatibility of organic matrix and inorganic filler, improve the dispersibility of inorganic particle in the silicone rubber, in a preferred embodiment, silane coupling agent adopts silane coupling agent KH-560.
The nano SIO2 has a composition similar to that of silicon rubber, so that the nano SIO2 is mutually adsorbed and intertwined, the dispersion of conductive carbon black is facilitated, the silicon rubber can be reinforced, molecular chains of the silicon rubber are not easy to slip and be damaged by external force, the work required by deformation is increased, the resistance delay time of the composite material can be reduced, and the static characteristic of the pressure-sensitive composite material is improved. In terms of dynamic characteristics, the addition of SIO2 can shorten the resistance stabilization time of the composite material.
In the process of printing the composite material, the addition amount of the carbon black has an important influence on the conductivity of the composite material. In the invention, the ratio of carbon black is 2-10% of the mass of the silicone rubber, and referring to fig. 3, the influence of the content ratio of carbon black/silicone rubber on the conductivity of the composite material is shown, and it can be seen from the figure that the filling amount of carbon black has a great influence on the conductivity of the composite material, and the conductivity of the composite material changes rapidly with the increase of the addition amount of carbon black. The change in conductivity of the sample is in accordance with the conductive path theory described above. When the mass fraction of the conductive particles is 2%, the effective conductive paths are still few even under the action of external force due to the fact that the conductive particles in unit volume are few and the distance between the carbon black particles in the matrix is large, and the resistivity is high; when the mass ratio of the conductive particles reaches 6%, gaps among the conductive particles in the matrix are reduced, a large number of effective conductive paths are formed, the resistance is rapidly reduced, when the filling amount is close to a critical threshold value, the conductive particles form a stable conductive network in the composite material, and the material resistance is rapidly reduced to cause a seepage phenomenon. The filling amount of the conductive particles is continuously increased, the particle gaps are further reduced, partial particles are in direct contact, the conduction mechanism in the material is mainly changed from a tunnel current effect to a conductive path effect, and the change trend of the resistivity of the composite material gradually tends to be smooth. The piezoresistive properties of the composite are most pronounced when near the percolation threshold.
A sample with the mass ratio of carbon black to silicon rubber being 6% is selected, the piezoresistive characteristics of the sample are researched through a pull pressure test bench and a universal meter, the piezoresistive effect curve is shown in figure 4, the composite material shows a good negative piezoresistive effect, and when the pressure exceeds a certain critical pressure value, the composite material shows a positive piezoresistive effect within a certain pressure range.
When the sensor is prepared by adopting the traditional coating process, the influence of the concentration of the conductive particles on the difficulty of preparing the sensor is rarely considered, and the spin coater or the coating tool can better coat the composite material on the template no matter the concentration is high or low. However, in the process flow of adopting screen printing, the concentration problem of the conductive particles needs to be considered, because the viscosity of the composite material is larger and the fluidity is poorer and poorer along with the increase of the concentration of the carbon black, which brings negative effects on the printing effect, when the mass ratio of the carbon black/silicon rubber is 2%, 6% and 10%, the influence of the concentration of the conductive particles on the printing performance of the composite material is researched, wherein the substrate material is Dow Corning 184, and the mesh of the printing screen is 200 meshes.
The experimental results show that:
when the mass ratio of carbon black to silicone rubber is 2%, the composite material is found to well penetrate through a screen printing plate in the printing process, a certain pasting phenomenon occurs, and the cured pressure-sensitive layer film is uneven in thickness, the main reason is that the viscosity of Dow Corning 184 is low, when the composite material with low concentration is adopted, the fluidity of the material is good, the composite material penetrating through the screen printing plate is large, the surface drying time of a matrix is long, the composite material still has certain fluidity on a PET film, and the phenomenon of uneven film thickness and the like occurs under the influence of external factors.
When the mass ratio of the carbon black to the silicone rubber is 6%, the viscosity is moderate in the printing of the composite material, and the film after printing and curing is uniform and smooth, and has no phenomena of paste surface deformation and the like.
When the mass ratio of carbon black/silicone rubber is 10%, it is found that the viscosity of the composite material is increased and the fluidity is deteriorated due to the increase of the content of the conductive particles, the material web penetrating ability is deteriorated, and after many times of printing and drying, the surface of the composite pressure-sensitive layer is rough and the thickness is low and uneven.
Meanwhile, researches find that in practical application requiring addition of high-concentration carbon black, a certain amount of solvent such as naphtha can be added before printing to maintain certain fluidity of the composite material, and the addition amount needs to be determined according to requirements of actual needs, processes, formulas and the like, but should not be too large. Experiments show that the addition amount is too large, the surface of the cured film is not smooth enough, the coverage rate after curing is low, and the problems of gaps and the like are easy to occur.
In a preferred embodiment, the present invention was based on a composite pressure sensitive material with a carbon black/silicone rubber ratio of 6%, and the effect of different meshes on the printing performance was investigated separately. Experiments show that:
1. in the printing experiment using the 100-mesh screen, the phenomenon of the paste surface occurred mainly because the mesh was too large and the amount of the composite material permeated was too large, so that the excessive material could not be dispersed rapidly and uniformly during the squeegee printing, resulting in the occurrence of the paste surface.
2. In the experiment using the 200-mesh screen plate, the surface of the composite pressure-sensitive layer is smooth, the thickness is moderate, and a better printing effect is obtained.
3. In the experiment that uses 300 mesh half tone, certain clearance has appeared in the compound pressure sensitive layer after the printing, even if print many times simultaneously, the membrane is thick still lower, and the main reason lies in the mesh is less, and the composite material that can see through the otter board is limited at every turn of printing, because the volume of permeating is undersize, the unable even cover on the electrode of composite material, certain clearance can appear promptly in the pressure sensitive layer, and this will produce the negative effect to the yields of sensor.
As can be seen from the above tests, the screen printing plate of 200 mesh is preferably used in the present invention.
The invention also discloses a preparation method of the large-area flexible sensor array, which is shown as a flow chart in figure 5 and comprises the following steps:
step S1: preparing a pressure-sensitive composite material;
step S2: preparing an electrode array on a flexible substrate according to application requirements, and respectively forming a first electrode array and a second electrode array, wherein any point electrode of the first electrode array corresponds to one point electrode of the second electrode array one by one to serve as an electrode group;
step S3: printing an uncured pressure-sensitive composite material on the surface of the first electrode array/the second electrode array directly in a screen printing mode, and forming a pressure-sensitive layer dot matrix after curing, wherein each dot unit in the pressure-sensitive layer dot matrix corresponds to each electrode group one by one, the pressure-sensitive composite material in each dot unit completely covers the dot electrode, and a sandwich structure or an interdigital structure is formed between the pressure-sensitive composite material and the corresponding electrode group;
step S4: leading out each point electrode and forming an electrode interface for connecting with an external circuit;
step S5: and integrally packaging the structure to form a large-area flexible sensor array.
By adopting the technical scheme, the large-area sensor array is manufactured by utilizing the printing process, the pressure-sensitive array manufactured by the printing process has better connectivity with the electrode array, better adhesive force, smaller volume and higher preparation efficiency, the repeated installation process of the traditional process is avoided, the process is simple, and the material utilization rate is high.
The procedure for the sandwich construction is described in detail below:
when a sandwich structure is formed among the pressure-sensitive layer lattice, the first electrode array and the second electrode array:
in the step S2, the conductive silver paste is directly printed and the flexible substrate is used to prepare the first electrode array and the second electrode array, and before printing, the surface of the flexible substrate is cleaned by using absolute ethyl alcohol and deionized water to remove impurities such as oil stains, thereby improving the adhesive force of the conductive silver paste. After printing, placing the flexible substrate in an oven at 120 ℃, and curing the silver paste for 20 min;
in step S3, the uncured pressure-sensitive composite material is directly printed on the surface of the first electrode array substrate/the second electrode array substrate by screen printing using the first electrode array substrate/the second electrode array substrate as the bottom plate, and a pressure-sensitive layer lattice is formed after curing, wherein in printing the composite material, two times of printing are generally adopted in order to enable the composite material to completely cover the electrode surface.
In step S4, the lead of the first electrode array substrate/the second electrode array substrate is led out by using the film piercing terminal, and the film piercing terminal is adopted, so that not only can stable electrical connectivity be ensured, but also the cured silver paste lead does not need to be exposed, oxidation of the silver paste is avoided, and the service life of the sensor array can be prolonged.
In step S5, an insulating adhesive layer is disposed between the first electrode array substrate and the second electrode array substrate, and covers all regions except the pressure-sensitive layer lattice, so that the first electrode array substrate and the second electrode array substrate are bonded and encapsulated face to face.
Referring to fig. 6, a sandwich type piezoresistive characteristic curve (array point is a circle with a diameter of 1 cm) is shown, which is prepared by directly printing an uncured composite material on the surface of an electrode array by a 200-mesh polyester screen plate with a carbon black/silicon rubber ratio of 6% to prepare a flexible pressure sensitive layer of a sensor.
The pressure experimental data of fig. 6 show that the array points are in negative pressure resistance effect within 0-2N, pressure sensing can be realized, the array thickness is about 0.3mm, the response time is about 1s, good pressure sensing sensitivity is achieved, and each array point is independent from each other, and crosstalk between signals can be reduced.
The above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core idea. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A flexible sensor array is characterized in that a first electrode array substrate, an insulating adhesive layer, a composite pressure-sensitive layer and a second electrode array substrate are sequentially arranged, wherein the first electrode array substrate and the second electrode array substrate respectively adopt an electrode array arranged on a flexible substrate to form a first electrode array and a second electrode array, and any point electrode of the first electrode array corresponds to one point electrode of the second electrode array one by one to serve as an electrode group; the composite pressure-sensitive layer is a pressure-sensitive layer lattice arranged between the first electrode array and the second electrode array, and any point unit in the pressure-sensitive layer lattice completely covers and is pressed between the corresponding electrode groups; the pressure-sensitive layer lattice is formed by directly printing an uncured pressure-sensitive composite material on the surface of the first electrode array/the second electrode array in a screen printing mode and curing; the insulating glue layer is used for bonding the first electrode array substrate and the second electrode array substrate.
2. The flexible sensor array of claim 1, wherein the first electrode array substrate and the second electrode array substrate are further provided with lead terminals electrically connected to the respective spot electrodes for connection to an external circuit.
3. The flexible sensor array according to claim 1 or 2, wherein the first electrode array substrate and the second electrode array substrate are printed with silver paste on the flexible substrate to form the first electrode array and the second electrode array, respectively.
4. The flexible sensor array of claim 1 or 2, wherein the flexible substrate is polyester PET or polyimide PI.
5. The flexible sensor array of claim 1 or 2, wherein the composite pressure sensitive layer is prepared from a pressure sensitive composite material comprising carbon black, silicone rubber, a silane coupling agent, nano SIO2, and naphtha.
6. The flexible sensor array of claim 5, wherein the carbon black is present in an amount of 2-10% by mass of the silicone rubber, the silane coupling agent is present in an amount of 2-5% by mass of the total formulation, the nano SIO2 is present in an amount of 2-10% by mass of the total formulation, and the balance is naphtha; the sum of the above components is 100%.
7. The flexible sensor array of claim 6, wherein the carbon black is present in an amount of 6% by mass of the silicone rubber.
8. The flexible sensor array of claim 5, wherein the carbon black is lion ECP600JD or Cabot BP 2000.
9. The flexible sensor array of claim 5, wherein the silicone rubber is Dow Corning 184 or 107 silicone rubber.
10. The flexible sensor array of claim 5, wherein the silane coupling agent is silane coupling agent KH-560.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113465796A (en) * | 2021-07-01 | 2021-10-01 | 西北工业大学 | Flexible integrated array pressure sensor and preparation method thereof |
| CN114459337A (en) * | 2022-03-15 | 2022-05-10 | 安徽大学 | High-sensitivity resistance type flexible tensile strain sensor based on spherical valve shape |
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2020
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113465796A (en) * | 2021-07-01 | 2021-10-01 | 西北工业大学 | Flexible integrated array pressure sensor and preparation method thereof |
| CN114459337A (en) * | 2022-03-15 | 2022-05-10 | 安徽大学 | High-sensitivity resistance type flexible tensile strain sensor based on spherical valve shape |
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