阅读说明：本技术 一种基于形状记忆的多重刺激自传感软体驱动器及其制备方法和应用 (multi-stimulation self-sensing software driver based on shape memory and preparation method and application thereof ) 是由 罗洪盛 周洹楷 姚仰荣 吴少英 易国斌 杨纪元 陈铭熙 于 2019-08-01 设计创作，主要内容包括：本发明属于柔性驱动与传感技术领域,公开了一种基于形状记忆的多重刺激自传感软体驱动器及其制备方法和应用。该自传感软体驱动器是将形状记忆聚合物溶于有机溶剂中,取上述溶液进行静电纺丝；将所得产品干燥,得到的形状记忆聚合物的无纺布；取纳米导电材料分散于分散剂中超声得分散液,然后将形状记忆聚合物的无纺布浸泡在分散液中超声；或者将纳米导电材料抽滤在形状记忆聚合物的无纺布,随后用去离子水进行清洗,烘干制得。本发明的自传感软体驱动器在响应外界刺激的同时具备自传感功能,通过电信号变化实时记录形变驱动回复过程,实现基于电信号的形变驱动的可视化。本发明应用在柔性电子传感、可穿戴电子设备或软体机器人领域中。(The invention belongs to the technical field of flexible driving and sensing, and discloses a shape memory-based multi-stimulation self-sensing soft driver and a preparation method and application thereof. The self-sensing soft driver is to dissolve the shape memory polymer in an organic solvent, and take the solution for electrostatic spinning; drying the obtained product to obtain the non-woven fabric of the shape memory polymer; dispersing the nano conductive material in a dispersing agent, performing ultrasonic treatment to obtain a dispersion liquid, and then soaking the non-woven fabric of the shape memory polymer in the dispersion liquid for ultrasonic treatment; or the nanometer conductive material is filtered on the non-woven fabric of the shape memory polymer, and then the non-woven fabric is washed by deionized water and dried to obtain the shape memory polymer. The self-sensing software driver disclosed by the invention has a self-sensing function while responding to external stimulation, and the deformation driving recovery process is recorded in real time through the change of an electric signal, so that the visualization of the deformation driving based on the electric signal is realized. The invention is applied to the field of flexible electronic sensing, wearable electronic equipment or soft robots.)

1. A multi-stimulation self-sensing soft body driver based on shape memory driving is characterized in that the self-sensing soft body driver is to dissolve a shape memory polymer into an organic solvent, and take the solution for electrostatic spinning; drying the obtained product at 20-40 ℃ to obtain the non-woven fabric of the shape memory polymer; dispersing the nano conductive material in a dispersing agent, performing ultrasonic treatment to obtain a dispersion liquid, and then soaking the non-woven fabric of the shape memory polymer in the dispersion liquid for ultrasonic treatment; or the nano conductive material is filtered on the non-woven fabric of the shape memory polymer, then the non-woven fabric is washed by deionized water and dried at the temperature of 30-40 ℃ to obtain the nano conductive material.

2. The shape memory actuation-based multi-stimulus self-sensing soft body actuator according to claim 1, wherein the ratio of the mass of the shape memory polymer to the volume of the organic solvent is (100-200) mg: 1 ml.

3. The shape memory actuation-based multi-stimulus self-sensing soft body actuator of claim 1, wherein the nano conductive material is a metal nanowire or a carbon nanomaterial.

4. The shape memory drive-based multi-stimulus self-sensing soft body driver of claim 3, wherein the metal nanowires are one or more of copper nanowires, silver nanowires, or gold nanowires; the carbon nano material is more than one of carbon nano tube, graphene or titanium carbide.

5. The shape memory actuation-based multi-stimulus self-sensing soft body actuator as claimed in claim 1, wherein the volume ratio of the mass of the nano conductive material to the volume of the dispersing agent is (0.1-5) mg: 1 ml.

6. The shape memory actuation-based multi-stimulus self-sensing soft body actuator of claim 1, wherein the molecular weight of the shape memory polymer is 1000 to 1000000; the shape memory polymer is polyurethane, polystyrene, polyethylene or epoxy resin; the organic solvent is more than one of N, N-dimethylformamide, N-dimethylacetamide and tetrahydrofuran.

7. The shape memory actuation-based multi-stimulus self-sensing software actuator of claim 1, wherein the dispersant is absolute ethanol, deionized water or isopropanol.

8. The shape memory drive-based multi-stimulus self-sensing soft body actuator of claim 1, wherein the parameters of the electrospinning are as follows: the total applied voltage is 16-20 kV, the distance between the injector and the roller is 15-25 cm, and the injection speed is 0.5-2 ml/h; the drying time at 20-40 ℃ is 1-12 h; the ultrasonic time is 0.5-2 h; the drying time at 30-40 ℃ is 1-12 h.

9. The method for preparing the shape memory drive-based multi-stimulus self-sensing soft body actuator according to any one of claims 1 to 8, comprising the following specific steps:

S1, dissolving a shape memory polymer in an organic solvent, performing electrostatic spinning on the solution, and drying a product in an oven at the temperature of 20-40 ℃ for 1-12 hours to prepare a non-woven fabric of the shape memory polymer;

s2, dispersing the nano conductive material in a dispersing agent to prepare a dispersion liquid;

And S3, soaking the non-woven fabric of the shape memory polymer in the dispersion liquid, ultrasonically treating or performing suction filtration, spraying and dripping to compound the nano conductive substance and the non-woven fabric, then cleaning with deionized water to remove the redundant nano conductive substance, and drying at 30-40 ℃ for 1-12 h to obtain the multi-stimulation self-sensing soft driver based on shape memory driving.

10. use of the shape memory actuation based multi-stimulus self-sensing software driver of any of claims 1-8 in the field of flexible electronic sensing, wearable electronics or software robotics.

Technical Field

The invention belongs to the technical field of flexible driving and sensing, and particularly relates to a shape memory-based multi-stimulation self-sensing soft driver and a preparation method and application thereof.

Background

Wearable electronic equipment, artificial muscles and soft robots have important application in the fields of human health monitoring, medical equipment development, disease diagnosis and treatment, virtual reality technology and the like, are popular research directions at present, attract the attention of extensive scientific research personnel, and promote the development of actuating materials and devices. The driving performance and process of the conventional actuator device can only be achieved by the camera acquisition system and the image processing technology, so that the actual driving situation can be obtained. However, in the case of insufficient light or no photography, such actuation devices tend to be limited, exhibit low efficiency, and are complex to use and unsuitable for complex and varied environments. Therefore, the sensing material element and the driving material element are assembled into a novel actuating device, the more specific actual driving process can be observed, and the real-time deformation process is fed back through the change of the electric signal.

however, most of the active material elements and sensing material elements under investigation are separated, and thus the entire device system is complex and non-integrated and does not facilitate spatial miniaturization. Meanwhile, devices that are too complex are often prone to various problems, such as circuit problems. Therefore, the development of a novel material integrating driving and sensing is urgently needed, namely, the driving process is accompanied with sensing, so that a user can obtain the real-time deformation and the driving process of a driving device through an electric signal, the harsh requirements of the traditional device on the environment are eliminated, and meanwhile, the simplicity and the high integration of a device system are improved. Further development of the driving device for the self-sensing function is crucial to the development of flexible electronic devices.

Currently, flexible electronic devices often require highly flexible, bend-resistant polymers such as silicone, polyethylene terephthalate, polyimide, and elastomeric polyester polyether, among others. The shape memory polymer can provide a shape fixing function while having the conditions, has a temporary shape, and has a wide application prospect. Shape memory polymers originated in 1948 and are widely used in textile, engineering and medical applications. Most shape memory polymers are thermotropic shape memory polymers, namely, the shape of the polymers can be endowed by heating and cooling near the glass transition temperature, and the polymers have large driving force and high deformation recovery force and become one of important choices of new driving materials. On the basis, the thermotropic shape memory polymer can be combined with other nano materials, and shape memory polymers such as electric drive, optical drive and the like can be prepared. For example, professor luohongsheng at the university of Guangdong industry successfully prepares the electro-shape memory polymer by using the shape memory polyurethane and the silver nanowires through a transfer method, and completes the whole driving process within 3 seconds at a voltage of 5V through an electrothermal effect. Therefore, the sensing material is combined with the shape memory polymer, so that a novel soft driver with integrated driving and sensing functions can be easily manufactured, and the novel soft driver plays an important role in the development of flexible electronic equipment such as soft robots and artificial muscles in the future.

Disclosure of Invention

to overcome the above-mentioned shortcomings and drawbacks of the prior art, it is a primary object of the present invention to provide a shape memory based multi-stimulus self-sensing soft body actuator. The driver combines driving and sensing, aims to establish controllable and quantitative relation between deformation driving and electric signals by virtue of the advantages of the shape memory polymer, and realizes visualization of the driving process based on the electric signals through external environment stimulation. The driving process and the change of deformation are monitored quantitatively. In addition, the material has stimulation sensing performance under the initial shape, such as heat, near infrared, water and the like, so that multiple stimulation sensing is realized.

another objective of the present invention is to provide a method for preparing the above-mentioned multi-stimulus self-sensing soft body actuator based on shape memory.

it is still another object of the present invention to provide the application of the above-mentioned multi-stimulus self-sensing soft body driver based on shape memory.

the purpose of the invention is realized by the following technical scheme:

A multi-stimulation self-sensing soft body driver based on shape memory drive is disclosed, wherein the self-sensing soft body driver is to dissolve a shape memory polymer in an organic solvent, and take the solution for electrostatic spinning; drying the obtained product at 20-40 ℃ to obtain the non-woven fabric of the shape memory polymer; dispersing the nano conductive material in a dispersing agent, performing ultrasonic treatment to obtain a dispersion liquid, and then soaking the non-woven fabric of the shape memory polymer in the dispersion liquid for ultrasonic treatment; or the nano conductive material is filtered on the non-woven fabric of the shape memory polymer, then the non-woven fabric is washed by deionized water and dried at the temperature of 30-40 ℃ to obtain the nano conductive material.

Preferably, the volume ratio of the mass of the shape memory polymer to the organic solvent is (100-200) mg: 1 ml.

Preferably, the nano conductive material is a metal nanowire or a carbon nanomaterial.

More preferably, the metal nanowire is one or more of a copper nanowire, a silver nanowire or a gold nanowire; the carbon nano material is more than one of carbon nano tube, graphene or titanium carbide.

Preferably, the volume ratio of the mass of the nano conductive material to the dispersant is (0.1-5) mg: 1 ml.

preferably, the molecular weight of the shape memory polymer is 1000-1000000; the shape memory polymer is polyurethane, polystyrene, polyethylene or epoxy resin; the organic solvent is more than one of N, N-dimethylformamide, N-dimethylacetamide and tetrahydrofuran.

Preferably, the dispersant is absolute ethyl alcohol, deionized water or isopropanol.

Preferably, the parameters of the electrostatic spinning are as follows: the total applied voltage is 16-20 kV, the distance between the injector and the roller is 15-25 cm, and the injection speed is 0.5-2 ml/h; the drying time at 20-40 ℃ is 1-12 h; the ultrasonic time is 0.5-2 h; the drying time at 30-40 ℃ is 1-12 h.

The preparation method of the shape memory drive-based multi-stimulation self-sensing software driver comprises the following specific steps:

s1, dissolving a shape memory polymer in an organic solvent, performing electrostatic spinning on the solution, and drying a product in an oven at the temperature of 20-40 ℃ for 1-12 hours to prepare a non-woven fabric of the shape memory polymer;

S2, dispersing the nano conductive material in a dispersing agent to prepare a dispersion liquid;

And S3, soaking the non-woven fabric of the shape memory polymer in the dispersion liquid, ultrasonically treating or performing suction filtration, spraying and dripping to compound the nano conductive substance and the non-woven fabric, then cleaning with deionized water to remove the redundant nano conductive substance, and drying at 30-40 ℃ for 1-12 h to obtain the multi-stimulation self-sensing soft driver based on shape memory driving.

the shape memory drive-based multi-stimulation self-sensing software driver is applied to the fields of flexible electronic sensing, wearable electronic equipment or software robots.

The self-sensing of the invention is that when the soft driver drives in a controllable way through external stimulation under different temporary shapes, the electric signal of the soft driver changes correspondingly along with the shape recovery, and the driving state can be quantitatively represented by the electric signal. Multiple stimuli are stimuli in which the soft body driver responds to two or more external stimuli, including but not limited to strain, temperature, water/humidity, near infrared light, solvent, electricity, and magnetism. The shape memory drive of the invention is that when the soft driver is heated to the temperature above the transformation temperature, the soft driver is deformed and fixed and is cooled to the temperature below the transformation temperature to obtain the memorized temporary shape, and the temperature exceeds the transformation temperature by external stimulation again, so that the shape recovery (such as shape, angle change and the like) is generated, which indicates that the drive is finished. The soft driver consists of a flexible shape memory polymer and a nanometer conductive network structure, wherein the shape memory polymer provides shape memory and driving capability, and the nanometer conductive network structure has the properties of responding to external stimuli and converting the stimuli into heat.

The self-sensing soft driver is composed of a shape memory fiber membrane and a hybridized one-dimensional or multi-dimensional conductive network, has a self-sensing function while responding to external stimulation, can pass through a specifically designed thermodynamic process, is endowed with a temporary shape and is fixed, and records a deformation driving recovery process in real time through the change of an electric signal to realize the visualization of the deformation driving based on the electric signal. The thermodynamic process is that the shape memory effect of the shape memory polymer is utilized, the polymer is slowly deformed above the glass transition temperature, the conductive network is deformed or cracked, the resistance is rapidly increased, and the temporary shape is fixed.

Compared with the prior art, the invention has the following beneficial effects:

1. The self-sensing soft driver can be fixed in any proportion by utilizing the shape memory function of the shape memory polymer, and the unique stimulus response function of the nano material is combined, so that an electric signal is fed back constantly under the condition of responding to external multiple stimuli, and the corresponding deformation condition is monitored.

2. The self-sensing soft driver of the invention can carry out arbitrary shape fixation, and compared with the traditional sensing material, the self-sensing soft driver can only carry out passive strain and strain recovery, but can not fix a certain proportion.

3. the self-sensing soft driver provided by the invention has a self-sensing function while responding to external stimulation, namely, the driver is driven by an external stimulation trigger material, and the deformation driving recovery process is recorded in real time through the change of an electric signal, so that the visualization of the driving process based on the electric signal is realized. Compared with the traditional sensing material, the self-sensing soft driver disclosed by the invention can drive the material in an isolated mode so as to realize strain recovery and self-sensing.

4. The preparation method is simple and rapid, and the shape memory self-sensing soft driver prepared by the method has good conductivity and shape memory capability.

5. The self-sensing software driver of the present invention is capable of responding to multiple external environmental stimuli, such as near infrared light, heat, water, etc.

Drawings

FIG. 1 is a schematic diagram of the driving process of the self-sensing software driver according to the present invention.

Fig. 2 is a resistance change rate of the shape memory polyurethane electrospun fabric loaded with graphene/carbon nanotubes in example 1 and example 3 under near infrared light stimulation;

Fig. 3 is a resistance change rate of the shape memory polyurethane electrospun fabric in which the carbon nanotubes and the graphene are ultrasonically loaded in example 1 when the fabric is lifted by 40 times of its own weight under near-infrared illumination, and the attached drawing is an optical picture of the process;

FIG. 4 is a scanning electron micrograph of a shape memory polyurethane electro-spun fabric according to example 1;

Fig. 5 is the shape memory polyurethane electrospun fabric ultrasonically loaded with carbon nanotubes of example 3.

Detailed Description

the following examples are presented to further illustrate the present invention and should not be construed as limiting the invention. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art. Reagents, methods and apparatus used in the present invention are conventional in the art unless otherwise indicated.