CN114295247A - Flexible temperature sensor, preparation method thereof and body temperature monitoring system - Google Patents

Abstract

The invention discloses a flexible temperature sensor, a preparation method thereof and a body temperature monitoring system. The flexible temperature sensor comprises a graphene/PDMS thermal sensitive material layer, a PDMS film packaging layer and a copper wire. The flexible temperature sensor adopts the serpentine graphene/PDMS thermal sensitive material, can quickly respond to body temperature change, improves the body temperature measurement efficiency, and effectively reduces the influence of strain signals generated by material stretching due to serpentine shape, thereby improving the accuracy of body temperature detection; simultaneously, PDMS film encapsulation can effectively laminate skin, when promoting the wearing travelling comfort, can reduce ambient temperature's influence. The body temperature monitoring system comprises a flexible temperature sensor, a system circuit and a mobile terminal application. The mobile terminal application can display the body temperature data in real time through graphs, curves and the like, so that the body temperature data can reflect the health condition of the user, and the user experience is greatly improved.

Description

A flexible temperature sensor, preparation method and body temperature monitoring system

technical field

The invention relates to the technical field of body temperature monitoring, in particular to a flexible temperature sensor, a preparation method and a body temperature monitoring system.

Background technique

Body temperature and human health are closely related. First of all, body temperature is an external reflection of human metabolism. For every 1°C drop in body temperature, basal metabolism will drop by 6% to 7%. When the room temperature drops, the human body will generate more heat by increasing basal metabolism, thereby maintaining body temperature. Therefore, the body temperature can be used to determine whether the body's metabolism is normal. However, the current body temperature measurement methods have many shortcomings, such as low efficiency, not fitting the skin, temperature sensors are easily affected by strain signals and ambient temperature, and so on.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a flexible temperature sensor, a preparation method and a body temperature monitoring system, so as to reduce the influence of ambient temperature and strain signal on the temperature sensor, and improve the efficiency, accuracy and wearing comfort of body temperature measurement.

For achieving the above object, the present invention provides the following scheme:

A flexible temperature sensor with a serpentine sandwich structure, comprising: a graphene/PDMS (Polydimethylsiloxane, polydimethylsiloxane) thermosensitive material layer, a PDMS film encapsulation layer and a copper wire; the graphene/PDMS thermosensitive material The shape of the layer is serpentine; both sides of the graphene/PDMS thermosensitive material layer are encapsulated by the PDMS thin film encapsulation layer; both ends of the graphene/PDMS thermosensitive material layer are drawn out through the copper wire.

Optionally, the graphene/PDMS thermosensitive material layer is prepared from graphene and PDMS.

Optionally, the mass ratio of graphene to PDMS in the graphene/PDMS thermosensitive material layer is 1:9 to 1:24.

Optionally, the thickness of the PDMS thin film encapsulation layer is 0.6 mm˜1.2 mm.

The present invention also provides a preparation method of a flexible temperature sensor with a serpentine sandwich structure, comprising:

The graphene is ultrasonically dispersed in n-heptane, PDMS is added and stirred thoroughly to obtain a graphene/PDMS suspension;

The graphene/PDMS suspension is heated and stirred until it is viscous, poured into a serpentine mold, put into an oven for heating and solidification, and a serpentine graphene/PDMS heat-sensitive material layer is obtained;

The two ends of the serpentine graphene/PDMS thermosensitive material layer are drawn out with copper wires, and both sides of the serpentine graphene/PDMS thermosensitive material layer are encapsulated by PDMS films to obtain the flexible temperature sensor.

Optionally, the graphene is ultrasonically dispersed by n-heptane, PDMS is added and fully stirred to obtain a graphene/PDMS suspension, which specifically includes:

Weigh a preset amount of graphene, add n-heptane to form a graphene/n-heptane mixed solution;

The graphene/n-heptane mixed solution is put into an ultrasonic cleaner for ultrasonic dispersion to obtain a graphene/n-heptane dispersion;

Mix Glue A and Glue B of Dow Corning SYLGARD 184 to obtain PDMS mixture;

Mixing the PDMS mixed solution and the graphene/n-heptane dispersion to obtain the graphene/PDMS suspension.

Optionally, the described graphene/PDMS suspension is heated and stirred until it is viscous and then poured into a serpentine mold, put into an oven for heating and solidification, to obtain a serpentine-shaped graphene/PDMS heat-sensitive material layer, specifically including:

The graphene/PDMS suspension is heated and stirred to become thick and then poured into a serpentine mold, and then placed in an oven for heating and solidification to obtain the serpentine graphene/PDMS heat-sensitive material layer; the graphene/PDMS heat-sensitive material layer is obtained; The mass ratio of graphene and PDMS in the sensitive material layer is 1:9～1:24; the temperature of the heating and stirring is 50～70°C; the temperature of the heating and curing is 60～100°C; the time of the heating and curing is For 2.5 ~ 4h.

Optionally, the two ends of the serpentine graphene/PDMS thermosensitive material layer are drawn out with copper wires, and the two sides of the serpentine graphene/PDMS thermosensitive material layer are encapsulated by PDMS films to obtain the result. The flexible temperature sensor includes:

Mix the A glue and B glue of Dow Corning SYLGARD 184 to obtain the PDMS mixture;

Pour the PDMS mixed solution into a mold and heat to solidify to obtain a PDMS thin film encapsulation layer; the PDMS thin film encapsulation layer has a thickness of 0.6 mm to 1.2 mm;

The two ends of the graphene/PDMS sensitive material layer are drawn out with copper wires, and one side of the graphene/PDMS sensitive material layer is attached to the PDMS thin film encapsulation layer;

A layer of the PDMS mixed solution is coated on the other side of the graphene/PDMS sensitive material layer, and the mixture is heated and cured in an oven to obtain the flexible temperature sensor.

The present invention also provides a body temperature monitoring system, comprising: the flexible temperature sensor, a system circuit and a mobile terminal application;

The flexible temperature sensor is connected to the system circuit through a copper wire; the mobile terminal application is wirelessly connected to the system circuit;

The flexible temperature sensor is used to collect temperature signals and transmit them to the system circuit through the copper wire;

The system circuit is configured to process the temperature signal to obtain body temperature data, and transmit the body temperature data to the mobile terminal application wirelessly;

The mobile terminal application visualizes the body temperature data.

Optionally, the system circuit includes: a power module, a data reading and processing circuit module, and a Bluetooth module; the data reading and processing circuit module is respectively connected to the power module and the Bluetooth module; the power module connected with the bluetooth module;

The power supply module is used for supplying power to the data reading and processing circuit module and the Bluetooth module;

The data reading and processing circuit module includes a voltage dividing circuit and a data processing circuit; the voltage dividing circuit is used to read the temperature signal in the form of voltage, and transmit the voltage signal to the data processing circuit; the The data processing circuit is used to amplify, filter, and A/D convert the voltage signal to obtain the body temperature data and transmit it to the Bluetooth module;

The Bluetooth module is used for wirelessly transmitting the body temperature data to the mobile terminal application.

According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

The invention provides a flexible temperature sensor and a preparation method thereof, and a body temperature monitoring system. The flexible temperature sensor is a serpentine sandwich structure, including: a graphene/PDMS thermosensitive material layer, a PDMS film encapsulation layer and a copper wire; the graphene/PDMS thermosensitive material layer has a serpentine shape; the graphene/PDMS thermosensitive material layer has a serpentine shape; Both sides of the PDMS thermosensitive material layer are encapsulated by the PDMS thin film encapsulation layer; both ends of the graphene/PDMS thermosensitive material layer are drawn out through the copper wire. The flexible temperature sensor of the invention adopts a serpentine graphene/PDMS heat-sensitive material layer, which can respond quickly to changes in body temperature, improve the efficiency of body temperature measurement, and the serpentine shape can effectively reduce the influence of strain signals generated by material stretching, thereby improving the accuracy of body temperature detection. Accuracy; at the same time, the PDMS film encapsulation layer can effectively fit the skin, improve wearing comfort, and reduce the impact of ambient temperature. In addition, the flexible temperature sensor also has the characteristics of simple process and low cost.

The body temperature monitoring system based on the serpentine sandwich structure flexible temperature sensor provided by the present invention collects body temperature data through the flexible temperature sensor, and displays it in real time through the mobile terminal application, so as to realize the real-time monitoring of body temperature, and solve the problem of the low efficiency of the current temperature measurement method and the problem of temperature Sensors are susceptible to problems such as ambient temperature and strain signals. The flexible temperature sensor based on the serpentine sandwich structure in the body temperature monitoring system can fit different parts for long-term body temperature monitoring; the mobile terminal application of the body temperature monitoring system can display the body temperature data in real time through graphs and curves, so as to reflect the user's temperature with body temperature data. Health status, which greatly improves the user experience.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings required in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some of the present invention. In the embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative labor.

1 is a schematic diagram of a discrete structure of a flexible temperature sensor with a serpentine sandwich structure provided by the present invention;

2 is a schematic structural diagram of a finished flexible temperature sensor with a serpentine sandwich structure provided by the present invention;

3 is a schematic structural diagram of a graphene/PDMS thermosensitive material layer provided by the present invention;

4 is a schematic structural diagram of a body temperature monitoring system provided by the present invention;

Symbol Description:

1. Flexible temperature sensor, 101, Graphene/PDMS thermal material layer, 102, PDMS film encapsulation layer, 103, copper wire, 2. System circuit, 201, Power module, 202, Data reading and processing circuit module, 203 , Bluetooth module, 3. Mobile application.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The purpose of the present invention is to provide a flexible temperature sensor, a preparation method and a body temperature monitoring system, so as to reduce the influence of ambient temperature and strain signal on the temperature sensor, and improve the efficiency, accuracy and wearing comfort of body temperature measurement.

In order to make the above objects, features and advantages of the present invention more clearly understood, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a schematic diagram of a discrete structure of a flexible temperature sensor with a serpentine sandwich structure provided by the present invention; FIG. 2 is a schematic structural diagram of a finished flexible temperature sensor with a serpentine sandwich structure provided by the present invention. Referring to FIG. 1 and FIG. 2 , a flexible temperature sensor 1 with a serpentine sandwich structure of the present invention includes: a graphene/PDMS thermosensitive material layer 101 , a PDMS thin film encapsulation layer 102 and a copper wire 103 . Both sides of the graphene/PDMS thermosensitive material layer 101 are encapsulated by the PDMS thin film encapsulation layer 102 , and both ends of the graphene/PDMS thermosensitive material layer 101 are drawn out through the copper wire 103 . In practical applications, the thickness of the PDMS thin film encapsulation layer 102 is 0.6 mm˜1.2 mm; preferably, the thickness of the PDMS thin film encapsulation layer 102 is 0.8 mm.

FIG. 3 is a schematic structural diagram of the graphene/PDMS thermosensitive material layer provided by the present invention. As shown in FIG. 3 , the shape of the graphene/PDMS thermosensitive material layer 101 is serpentine; and the graphene/PDMS thermosensitive material layer 101 is prepared from graphene and PDMS. In practical applications, the mass ratio of graphene to PDMS in the graphene/PDMS thermosensitive material layer 101 is 1:9 to 1:24; preferably, the mass ratio of graphene to PDMS is 1:19.

The preparation method of the flexible temperature sensor with the serpentine sandwich structure will be described in detail below.

A preparation method of a flexible temperature sensor 1 with a serpentine sandwich structure of the present invention includes:

Step (1): ultrasonically dispersing graphene through n-heptane, adding polydimethylsiloxane PDMS and stirring well to obtain a graphene/PDMS suspension.

In the present invention, the graphene is ultrasonically dispersed in n-heptane, PDMS is added and fully stirred to obtain a graphene/PDMS suspension. First weigh a certain amount of graphene, add n-heptane, the n-heptane just does not pass the graphene, put the graphene/n-heptane mixture into an ultrasonic cleaner for ultrasonic dispersion for 2h, and obtain graphene/n-heptane alkane dispersion. PDMS adopts Dow Corning SYLGARD 184, and the PDMS mixture is obtained by mixing the A glue and B glue of Dow Corning SYLGARD 184 at a mass ratio of 10:1. The PDMS mixed solution and the graphene/n-heptane dispersion were mixed to obtain a graphene/PDMS suspension. In the present invention, the mass ratio of graphene and PDMS is preferably 1:9 to 1:24, more preferably 1:19.

Therefore, the step (1) specifically includes:

Weigh a preset amount of graphene, add n-heptane to form a graphene/n-heptane mixed solution; put the graphene/n-heptane mixed solution into an ultrasonic cleaner for ultrasonic dispersion to obtain graphene/n-heptane Heptane dispersion; Mix the A glue and B glue of Dow Corning SYLGARD 184 uniformly to obtain PDMS mixing; Mix the PDMS mixed solution and the graphene/n-heptane dispersion to obtain the graphene/PDMS suspension.

In practical application, the mass ratio of glue A and glue B of Dow Corning SYLGARD 184 is 10:1.

Step (2): the graphene/PDMS suspension is heated and stirred until it is thick, poured into a serpentine mold, and heated and cured in an oven to obtain a serpentine graphene/PDMS heat-sensitive material layer 101.

After the graphene/PDMS suspension is obtained, the graphene/PDMS suspension is heated and stirred until viscous and then poured into a serpentine mold, placed in an oven for heating and solidification, to obtain a serpentine graphene/PDMS heat-sensitive material layer 101. In the present invention, the heating and stirring temperature is preferably 50°C to 70°C, and more preferably 60°C. In the present invention, the heating and curing temperature is preferably 60°C to 100°C, more preferably 80°C; the heating and curing time is preferably 2.5h to 4h, more preferably 3h.

Therefore, the step (2) specifically includes:

The graphene/PDMS suspension is heated and stirred to become viscous and then poured into a serpentine mold, put into an oven for heating and solidification, to obtain the serpentine graphene/PDMS heat-sensitive material layer 101. In practical applications, the mass ratio of graphene to PDMS in the graphene/PDMS thermosensitive material layer 101 is 1:9 to 1:24; preferably, the mass ratio of graphene to PDMS is 1:19. In practical applications, the temperature of the heating and stirring is 50°C to 70°C; preferably, the temperature of the heating and stirring is 60°C. In practical applications, the temperature for heating and curing is 60°C to 100°C; preferably, the temperature for heating and curing is 80°C. In practical applications, the heating and curing time is 2.5h to 4h; preferably, the heating and curing time is 3h.

Step (3): The two ends of the serpentine graphene/PDMS thermosensitive material layer 101 are drawn out with copper wires 103, and both sides of the serpentine graphene/PDMS thermosensitive material layer 101 are passed through the PDMS film encapsulation layer. 102 encapsulation to obtain the flexible temperature sensor 1 .

After obtaining the serpentine graphene/PDMS thermosensitive material layer 101, the two ends of the serpentine graphene/PDMS thermosensitive material layer 101 are drawn out with copper wires 103, and the two sides are encapsulated by the PDMS film encapsulation layer 102 to obtain a flexible temperature Sensor 1. In the present invention, the PDMS thin film encapsulation layer 102 is prepared by Dow Corning SYLGARD 184. After mixing glue A and glue B to obtain a PDMS mixture, pour it into a mold to heat and solidify to obtain the PDMS thin film encapsulation layer 102 . The mixing ratio of the A glue and the B glue is preferably 8 to 11:1, more preferably 10:1; the mold is preferably a petri dish; the thickness of the PDMS film is preferably 0.6 mm to 1.2 mm, more preferably 0.8 mm. After the PDMS thin film encapsulation layer 102 is obtained, the two ends of the graphene/PDMS sensitive material layer 101 are drawn out with copper wires 103, attached to the PDMS thin film encapsulation layer 102, and then coated with a layer of PDMS mixed solution on the upper layer, and placed in an oven Heating and curing to obtain a sandwich structure flexible temperature sensor 1 with an upper and lower PDMS package and a middle layer of sensitive material. In the present invention, the heating and curing temperature is preferably 60-100°C, more preferably 80°C; the heating and curing time is preferably 2.5h-4h, more preferably 3h.

Therefore, the step (3) specifically includes:

Mix the A glue and B glue of Dow Corning SYLGARD 184 to obtain a PDMS mixed solution; pour the PDMS mixed solution into a mold to heat and solidify to obtain a PDMS thin film encapsulation layer 102; both ends of the graphene/PDMS sensitive material layer 101 are coated with copper The line 103 is drawn out, and one side of the graphene/PDMS sensitive material layer 101 is pasted on the PDMS thin film encapsulation layer 102; the other side of the graphene/PDMS sensitive material layer 101 is coated with a layer of the PDMS mixed solution , put it into an oven for heating and curing, and obtain the flexible temperature sensor 1 .

In practical applications, the thickness of the PDMS thin film encapsulation layer 102 is 0.6 mm˜1.2 mm; preferably, the thickness of the PDMS thin film encapsulation layer 102 is 0.8 mm. In practical application, the mixing ratio of glue A and glue B of the Dow Corning SYLGARD 184 is preferably 8:1 to 11:1, and more preferably, the mixing ratio of glue A and glue B is 10:1. In practical applications, the temperature for heating and curing is 60°C to 100°C; preferably, the temperature for heating and curing is 80°C. In practical applications, the heating and curing time is 2.5h to 4h; preferably, the heating and curing time is 3h. In practical applications, the mold is preferably a petri dish.

The invention constructs a body temperature monitoring system based on a serpentine sandwich structure flexible temperature sensor through a simple process and low cost, which can effectively reduce the strain signal generated by the material stretching and the influence of the ambient temperature on the temperature sensor, and can also Effectively monitor body temperature for a long time to reflect the user's health status.

Graphene is a new type of two-dimensional carbon nanomaterial with a single-layer sheet structure composed of carbon atoms. Graphene is not only the thinnest known material, but it is also very strong and rigid. As a simple substance, it can transfer electrons faster than known conductors at room temperature. At the same time, graphene can still maintain good chemical stability under bending and stretching conditions. The excellent properties of graphene make it an excellent candidate for heat-sensitive materials.

Polydimethylsiloxane (PDMS) is a hydrophobic silicone material. PDMS film is a kind of high-resolution polymer film with transparent color, good flexibility, excellent chemical stability, thermal stability and biocompatibility. Because PDMS films have many of the above excellent properties, PDMS films are widely used in various smart electronic and flexible electronic devices. PDMS films adhere to the skin and are harmless to the human body, making them an excellent choice for the preparation of flexible temperature sensors.

Therefore, the present invention uses graphene and PDMS materials to make the graphene/PDMS thermosensitive material layer of the serpentine sandwich structure flexible temperature sensor, which can respond quickly to changes in body temperature, improve the efficiency of body temperature measurement, and the serpentine shape can effectively reduce material stretching The influence of generating strain signals improves the accuracy of body temperature detection.

At the same time, the present invention uses PDMS film to encapsulate the graphene/PDMS heat-sensitive material layer of the serpentine sandwich structure flexible temperature sensor, which can effectively fit the skin, improve wearing comfort, and reduce the influence of ambient temperature.

In order to better illustrate the preparation method of the graphene/PDMS thermosensitive material layer 101 of the flexible temperature sensor, three specific examples of fabricating the serpentine-shaped graphene/PDMS thermosensitive material layer 101 are provided below.

Example 1

Weigh 0.4g of graphene and place it in a beaker, add a certain amount of n-heptane and stir, the n-heptane just does not cover the graphene, put it into an ultrasonic cleaner for ultrasonic dispersion for 1h to obtain a graphene/n-heptane dispersion . According to the mass ratio of A glue and B glue 10:1, a total of 9.6 g of Dow Corning 184A glue and B glue was weighed, and stirred evenly to obtain a PDMS mixed solution. The graphene/n-heptane dispersion and the PDMS mixture were mixed and stirred for 20 minutes to obtain a graphene/PDMS suspension.

The graphene/PDMS suspension was heated and stirred at 60 °C for 2 h until viscous. Pour the graphene/PDMS suspension into the serpentine mask, and put it in an oven at 60°C for heating and curing for 4 hours to obtain a serpentine graphene/PDMS thermosensitive material layer 101, as shown in Figure 3, the graphene/PDMS thermosensitive material Layer 101 has a length of 2.1 cm and a width of 1.4 cm.

Example 2

Weigh 0.5g of graphene and place it in a beaker, add a certain amount of n-heptane and stir, the n-heptane just does not cover the graphene, put it into an ultrasonic cleaner for ultrasonic dispersion for 1h to obtain a graphene/n-heptane dispersion . According to the mass ratio of glue A and glue B at 10:1, a total of 9.5 g of Dow Corning 184A glue and glue B were weighed and stirred to obtain a PDMS mixed solution. The graphene/n-heptane dispersion and the PDMS mixture were mixed and stirred for 20 minutes to obtain a graphene/PDMS suspension.

The graphene/PDMS suspension was heated and stirred at 60 °C for 2 h until viscous. Pour the graphene/PDMS suspension into the serpentine mask, and put it in an oven at 80°C for heating and curing for 3 hours to obtain a serpentine graphene/PDMS thermosensitive material layer, as shown in Figure 3, the graphene/PDMS thermosensitive material layer 101 has a length of 2.1cm and a width of 1.4cm.

Example 3

1 g of graphene was weighed and placed in a beaker, a certain amount of n-heptane was added and stirred until the n-heptane had passed the graphene, and then placed in an ultrasonic cleaner for ultrasonic dispersion for 1 h to obtain a graphene/n-heptane dispersion. A total of 9 g of Dow Corning 184A glue and B glue were weighed according to the mass ratio of A glue to B glue of 10:1, and stirred to obtain a PDMS mixed solution. The graphene/n-heptane dispersion and the PDMS mixture were mixed and stirred for 20 minutes to obtain a graphene/PDMS suspension.

The graphene/PDMS suspension was heated and stirred at 60 °C for 2 h until viscous. Pour the graphene/PDMS suspension into the serpentine mask, put it in an oven at 100°C for heating and curing for 2.5 hours, and obtain a serpentine graphene/PDMS thermosensitive material layer, as shown in Figure 3, the graphene/PDMS thermosensitive material Layer 101 has a length of 2.1 cm and a width of 1.4 cm.

In order to better illustrate the preparation method of the PDMS thin film encapsulation layer 102 and the flexible temperature sensor, four specific examples of fabricating the PDMS thin film encapsulation layer 102 and the flexible temperature sensor 1 of the serpentine sandwich structure are provided below.

Example 4

A total of 10 g of Dow Corning 184A glue and B glue were weighed according to the mass ratio of glue A and glue B, and a total of 10 g was obtained by stirring to obtain a PDMS mixture. An appropriate amount was applied to a petri dish, and the petri dish was heated and cured at 60°C in an oven. 4h, the PDMS thin film encapsulation layer 102 was obtained, and the film thickness was 0.6 mm. One side of the serpentine graphene/PDMS sensitive material layer 101 is attached to the PDMS thin film encapsulation layer 102 , and copper wires 103 are used to lead out both ends of the graphene/PDMS sensitive material layer 101 . A layer of PDMS mixed solution is coated on the other side of the graphene/PDMS sensitive material layer 101, and then heated and cured in an oven at 60° C. for 4 hours to obtain an upper and lower PDMS film encapsulation layer 102, and the middle layer is serpentine graphene/PDMS. The sandwich structure flexible temperature sensor 1 of the sensitive material layer 101 is shown in FIG. 2 .

Example 5

A total of 10 g of Dow Corning 184A glue and B glue was weighed according to the mass ratio of glue A and glue B 10:1, stirred evenly to obtain a PDMS mixture, took an appropriate amount and applied it to a petri dish, and placed the petri dish in an oven at 80 °C to heat and solidify 3h, a PDMS film was obtained with a film thickness of 0.8 mm. One side of the serpentine graphene/PDMS sensitive material layer 101 is attached to the PDMS thin film encapsulation layer 102 , and copper wires 103 are used to lead out both ends of the graphene/PDMS sensitive material layer 101 . A layer of PDMS mixed solution is coated on the other side of the graphene/PDMS sensitive material layer 101, and is heated and cured in an oven at 80° C. for 3 hours to obtain an upper and lower PDMS film encapsulation layer 102, and the middle layer is serpentine graphene/PDMS The sandwich structure flexible temperature sensor 1 of the sensitive material layer 101 is shown in FIG. 2 .

Example 6

Weigh Dow Corning 184A glue and B glue in a total of 10g according to the mass ratio of glue A and glue B at 11:1, stir evenly to obtain a PDMS mixture, apply an appropriate amount to a petri dish, and place the petri dish in an oven at 80 ℃ to heat and solidify After 4 h, a PDMS film was obtained with a film thickness of 0.8 mm. One side of the serpentine graphene/PDMS sensitive material layer 101 is attached to the PDMS thin film encapsulation layer 102 , and copper wires 103 are used to lead out both ends of the graphene/PDMS sensitive material layer 101 . A layer of PDMS mixed solution is coated on the other side of the graphene/PDMS sensitive material layer 101, and then heated and cured in an oven at 80° C. for 3 hours to obtain an upper and lower PDMS thin film encapsulation layer 102, and the middle layer is serpentine graphene/PDMS The sandwich structure flexible temperature sensor 1 of the sensitive material layer 101 is shown in FIG. 2 .

Example 7

Weigh 10 g of Dow Corning 184A glue and B glue according to the mass ratio of glue A and glue B at 11:1, stir evenly to obtain a PDMS mixture, apply an appropriate amount to a petri dish, and place the petri dish in an oven to heat and cure at 100°C After 2.5 h, a PDMS film was obtained, and the film thickness was 1.2 mm.

One side of the serpentine graphene/PDMS sensitive material layer 101 is attached to the PDMS thin film encapsulation layer 102 , and copper wires 103 are used to lead out both ends of the graphene/PDMS sensitive material layer 101 . A layer of PDMS mixed solution is coated on the other side of the graphene/PDMS sensitive material layer 101, and then placed in an oven for heating and curing at 100° C. for 2.5 hours to obtain an upper and lower PDMS film encapsulation layer 102, and the middle layer is serpentine graphene/ The sandwich structure flexible temperature sensor 1 of the PDMS sensitive material layer 101 is shown in FIG. 2 .

FIG. 4 is a schematic structural diagram of a body temperature monitoring system provided by the present invention. After the flexible temperature sensor 1 is obtained by the above preparation method, the flexible temperature sensor 1 is combined with the system circuit 2 , and the body temperature data is read and processed and then transmitted to the mobile terminal application 3 . In the present invention, the system circuit 2 includes a power module 201 , a data reading and processing circuit module 202 and a Bluetooth module 203 . Since the flexible temperature sensor 1 is a resistance temperature sensor, a voltage divider circuit is used to read the temperature signal in the form of voltage, and the voltage signal is transmitted to the data processing circuit for amplification, filtering, A/D conversion and other processing, and then the data information is transmitted to The Bluetooth module 203 , the Bluetooth module 203 wirelessly transmits data information to the mobile terminal application 3 . After acquiring the information transmitted by the Bluetooth module 203, the mobile application 3 displays the body temperature data in real time by means of graphs, curves, and the like.

Therefore, as shown in FIG. 4 , a body temperature monitoring system provided by the present invention includes: a flexible temperature sensor 1 , a system circuit 2 and a mobile terminal application 3 .

Specifically, the flexible temperature sensor 1 is connected to the system circuit 2 through a copper wire 103 , and the mobile terminal application 3 is wirelessly connected to the system circuit 2 . The flexible temperature sensor 1 is used to collect temperature signals and transmit them to the system circuit 2 through the copper wire 103 . The system circuit 2 obtains body temperature data after performing data processing on the temperature signal, and transmits the body temperature data to the mobile terminal application 3 wirelessly. The mobile terminal application 3 visualizes the obtained body temperature data.

Specifically, the system circuit 2 includes: a power module 201 , a data reading and processing circuit module 202 and a Bluetooth module 203 . The data reading and processing circuit module 202 is connected with the power module 201 and the Bluetooth module 203 respectively, and the power module 201 is connected with the Bluetooth module 203 at the same time. The power supply module 201 is used for supplying power to the data reading and processing circuit module 202 and the Bluetooth module 203 .

Specifically, the data reading and processing circuit module 202 includes a voltage dividing circuit and a data processing circuit. The voltage dividing circuit is used to read the temperature signal in the form of voltage, and transmit the voltage signal to the data processing circuit. The data processing circuit is used to amplify, filter, and A/D convert the voltage signal to obtain the body temperature data and transmit it to the Bluetooth module 203 . The Bluetooth module 203 is used for wirelessly transmitting the body temperature data to the mobile terminal application 3 . That is, since the flexible temperature sensor 1 is a resistance temperature sensor, a voltage divider circuit is used to read the temperature signal in the form of voltage, and the voltage signal is transmitted to the data processing circuit, and the voltage signal is amplified, filtered, and A/D converted. Wait for processing to get body temperature data. Then, the body temperature data information is transmitted to the Bluetooth module 203 , and the Bluetooth module 203 wirelessly transmits the body temperature data information to the mobile terminal application 3 . After acquiring the information transmitted by the Bluetooth module 203, the mobile terminal application 3 displays the body temperature data in real time by means of graphs, curves, and the like.

In practical applications, Altium Designer can be used to complete the system circuit PCB design; AndroidStudio can be used for mobile terminal development, and mobile terminal applications can be written.

The invention provides a flexible temperature sensor and a preparation method thereof. The flexible temperature sensor adopts a serpentine graphene/PDMS heat-sensitive material layer, which can quickly respond to changes in body temperature, and the serpentine shape can effectively reduce the stress of material stretching to generate strain signals. This improves the accuracy of body temperature detection. At the same time, the PDMS film encapsulation layer can effectively fit the skin, improve wearing comfort, and reduce the impact of ambient temperature.

Compared with the prior art, the present invention also constructs a body temperature monitoring system based on a serpentine sandwich structure flexible temperature sensor in a simple process and low cost manner. The body temperature monitoring system provided by the present invention collects body temperature data through a flexible temperature sensor, and displays it in real time through a mobile terminal application, so as to realize the real-time monitoring of body temperature, and solve the problem that the current temperature measurement method is inefficient and the temperature sensor is easily affected by environmental temperature and strain signals. And other issues. The mobile application can display body temperature data in real time through graphs and curves, which greatly improves the user experience. The body temperature monitoring system based on the flexible temperature sensor of the snake-shaped sandwich structure can be fitted to different parts for body temperature monitoring, so as to reflect the user's health status with body temperature data.

The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the various embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant part can be referred to the description of the method.

In this paper, specific examples are used to illustrate the principles and implementations of the present invention. The descriptions of the above embodiments are only used to help understand the methods and core ideas of the present invention; meanwhile, for those skilled in the art, according to the present invention There will be changes in the specific implementation and application scope. In conclusion, the contents of this specification should not be construed as limiting the present invention.

Claims (10)

1. a flexible temperature sensor of serpentine sandwich structure, is characterized in that, comprises: Graphene/polydimethylsiloxane PDMS heat sensitive material layer, PDMS thin film encapsulation layer and copper wire; Described graphene/PDMS thermal The shape of the sensitive material layer is serpentine; both sides of the graphene/PDMS thermal sensitive material layer are encapsulated by the PDMS thin film encapsulation layer; both ends of the graphene/PDMS thermal sensitive material layer are drawn out through the copper wire. 2 . The flexible temperature sensor according to claim 1 , wherein the graphene/PDMS thermosensitive material layer is prepared from graphene and PDMS. 3 . 3 . The flexible temperature sensor according to claim 2 , wherein the mass ratio of graphene to PDMS in the graphene/PDMS thermosensitive material layer is 1:9 to 1:24. 4 . 4 . The flexible temperature sensor according to claim 1 , wherein the PDMS thin film encapsulation layer has a thickness of 0.6 mm to 1.2 mm. 5 . 5. A preparation method of a flexible temperature sensor of a serpentine sandwich structure, characterized in that, comprising: The graphene is ultrasonically dispersed in n-heptane, polydimethylsiloxane PDMS is added and fully stirred to obtain a graphene/PDMS suspension; The graphene/PDMS suspension is heated and stirred until it is viscous, poured into a serpentine mold, put into an oven for heating and solidification, and a serpentine graphene/PDMS heat-sensitive material layer is obtained; The two ends of the serpentine graphene/PDMS thermosensitive material layer are drawn out with copper wires, and both sides of the serpentine graphene/PDMS thermosensitive material layer are encapsulated by PDMS films to obtain the flexible temperature sensor. 6. preparation method according to claim 5, is characterized in that, described by the ultrasonic dispersion of Graphene by n-heptane, adds PDMS and fully stirs, obtains Graphene/PDMS suspension, specifically comprises: Weigh a preset amount of graphene, add n-heptane to form a graphene/n-heptane mixed solution; The graphene/n-heptane mixed solution is put into an ultrasonic cleaner for ultrasonic dispersion to obtain a graphene/n-heptane dispersion; Mix Glue A and Glue B of Dow Corning SYLGARD 184 to obtain PDMS mixture; Mixing the PDMS mixed solution and the graphene/n-heptane dispersion to obtain the graphene/PDMS suspension. 7. preparation method according to claim 5, is characterized in that, after described Graphene/PDMS suspension is heated and stirred to be viscous and poured into serpentine mould, put into baking oven and heat and solidify, obtain serpentine. Graphene/PDMS thermosensitive material layer, including: The graphene/PDMS suspension is heated and stirred to become thick and then poured into a serpentine mold, and then placed in an oven for heating and solidification to obtain the serpentine graphene/PDMS heat-sensitive material layer; the graphene/PDMS heat-sensitive material layer is obtained; The mass ratio of graphene and PDMS in the sensitive material layer is 1:9～1:24; the temperature of the heating and stirring is 50～70°C; the temperature of the heating and curing is 60～100°C; the time of the heating and curing is For 2.5 ~ 4h. 8. preparation method according to claim 5, is characterized in that, described serpentine Graphene/PDMS thermosensitive material layer both ends are drawn out with copper wire, and described serpentine Graphene/PDMS The two sides of the heat-sensitive material layer are encapsulated by the PDMS film to obtain the flexible temperature sensor, which specifically includes: Mix the A glue and B glue of Dow Corning SYLGARD 184 to obtain the PDMS mixture; Pour the PDMS mixed solution into a mold and heat to solidify to obtain a PDMS thin film encapsulation layer; the PDMS thin film encapsulation layer has a thickness of 0.6 mm to 1.2 mm; The two ends of the graphene/PDMS sensitive material layer are drawn out with copper wires, and one side of the graphene/PDMS sensitive material layer is attached to the PDMS thin film encapsulation layer; A layer of the PDMS mixed solution is coated on the other side of the graphene/PDMS sensitive material layer, and the mixture is heated and cured in an oven to obtain the flexible temperature sensor. 9. A body temperature monitoring system, comprising: the flexible temperature sensor according to claim 1, a system circuit and a mobile terminal application; The flexible temperature sensor is connected to the system circuit through a copper wire; the mobile terminal application is wirelessly connected to the system circuit; The flexible temperature sensor is used to collect temperature signals and transmit them to the system circuit through the copper wire; The system circuit is configured to process the temperature signal to obtain body temperature data, and transmit the body temperature data to the mobile terminal application wirelessly; The mobile terminal application visualizes the body temperature data. 10 . The body temperature monitoring system according to claim 9 , wherein the system circuit comprises: a power supply module, a data reading and processing circuit module, and a Bluetooth module; the data reading and processing circuit module is respectively connected with the the power module is connected with the bluetooth module; the power module is connected with the bluetooth module; The power module is used for powering the data reading and processing circuit module and the Bluetooth module; The data reading and processing circuit module includes a voltage dividing circuit and a data processing circuit; the voltage dividing circuit is used to read the temperature signal in the form of voltage, and transmit the voltage signal to the data processing circuit; the The data processing circuit is used to amplify, filter, and A/D convert the voltage signal to obtain the body temperature data and transmit it to the Bluetooth module; The Bluetooth module is used for wirelessly transmitting the body temperature data to the mobile terminal application.

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