CN113683788B - Stretchable, compressible and anti-freezing organic hydrogel electrolyte, preparation method and application - Google Patents

Abstract

The invention belongs to the field of functional polymer hydrogels, and particularly relates to a stretchable, compressible and antifreeze organic hydrogel electrolyte, a preparation method and applications. The organic hydrogel electrolyte provided by the present invention is formed from methacryloylethylsulfobetaine, acrylamide, and dimethyl sulfoxide and water as solvents through radical initiation polymerization, and the cross-linked network is doped with soybean protein. The organic hydrogel electrolyte provided by the invention has a maximum fracture strain of up to 762.5%, can still recover to the original state after repeated 500% tensile or 80% compressive strain, and has excellent mechanical properties; the room temperature conductivity can reach 37.5mS cm ^‑1 , at ‑20℃, the charge and discharge time is still 13s, so it has good low-temperature electrical properties, and can achieve the technical effect of using hydrogel electrolytes as supercapacitor electrolytes; it has strain sensitivity and can achieve hydrogelation Technical effects of gel electrolytes as stable sensor materials.

Description

Stretchable, compressible and antifreeze organohydrogel electrolyte, preparation method and application

technical field

The invention belongs to the field of functional polymer hydrogels, and particularly relates to a stretchable, compressible and antifreeze organic hydrogel electrolyte, a preparation method and applications.

Background technique

Hydrogel is a special kind of material. It is formed by cross-linking of hydrated polymer segments with a large amount of water in the interstices. As a result, hydrogels generally appear soft and moist in appearance. Due to the abundant hydrophilic groups on its segments, hydrogels usually have good water absorption and water retention properties, and some hydrogels can even absorb about 2,000 times their own weight in water. These groups also provide a large number of adsorption sites for electrolyte ions in solution, making it one of the ideal materials for electrolytes. More importantly, the hydrogel material has good designability and tunability, which makes it possible for the modified hydrogel to adapt to a variety of uses, such as stretchable hydrogels, self-healing hydrogels, Mechanochromic hydrogels, degradable hydrogels, etc.

Ductile hydrogels (referring to hydrogels with strong energy-absorbing capacity during plastic deformation and fracture) have attracted increasing attention due to their excellent mechanical properties and functions. Although hydrogels have been widely used due to their high ductility and strength, and hydrogel electrolytes can withstand denaturation and mechanical damage to a certain extent, they have stretchable, compressible, frost-resistant and low-temperature electrical conductivity properties. The research on excellent hydrogel electrolytes is still in the preliminary stage, so the electrical properties, mechanical stability, and cycling stability at room temperature or low temperature are still the focus of research on hydrogel electrolytes.

The weak mechanical strength of most hydrogel electrolytes largely limits their practicality, so various methods have been utilized to strengthen and toughen hydrogels, as described in Chinese literature (Nan Jingya, et al. soybean protein Preparation of reinforced hydrogel electrolyte and its application in all-solid-state supercapacitors, Polymer Materials Science and Engineering [J]. 2021, 37(03), 143-150) Polyacrylamide chains are cross-linked to form a three-dimensional network Structure, through the electrostatic attraction between soybean protein nanoparticles and polyacrylamide, soybean protein is introduced into the polyacrylamide cross-linked network, and replaced by phosphoric acid solution to obtain a soybean protein-enhanced hydrogel electrolyte, yes hydrogel No structural fracture or damage occurred after 100 cyclic compressions at 80% strain, and the supercapacitor composed of the polypyrrole-carbon nanotube paper had good capacitance stability, but its conductivity at low temperature was relatively low. Low even can not meet the use of extremely low temperature. At present, how to improve the antifreeze performance of hydrogel electrolytes on the premise of maintaining mechanical properties has become a research hotspot. As in the prior art, a hydrogel electrolyte containing antifreeze zwitterions and a supercapacitor prepared therefrom, the hydrogel electrolyte still has a high ionic conductivity of 1.26 S·m ^-1 at -40°C, and at the same time has excellent However, the mechanical properties and cycle performance of this electrolyte still cannot meet the flexibility requirements for supercapacitors, so it is urgent to propose a new comprehensive Hydrogel electrolytes with excellent performance are prepared into supercapacitors, so that the mechanical properties and low temperature performance of supercapacitors can meet the needs of flexible wearable supercapacitors, and this supercapacitor can still be guaranteed in extremely cold weather Normal use.

SUMMARY OF THE INVENTION

In order to solve the problem that the tensile and compressive properties of the existing hydrogel materials are improved while the tensile and compressive properties are significantly decreased, the present invention provides a stretchable, compressible and antifreeze organic hydrogel electrolyte, a preparation method and an application. Freezing monomers and strengthening and toughening components make the obtained hydrogel electrolytes have excellent tensile-compression cycle performance and electrical conductivity.

In order to achieve the above object, the present invention adopts the following technical solutions:

A method for preparing a stretchable, compressible, and antifreeze organic hydrogel electrolyte, characterized in that the steps are as follows:

(1) Soybean protein isolate, solvent are added in reaction vessel, heat and stir to obtain mixed solution;

(2) Add one or two monomers of methacryloyl ethyl sulfobetaine (SBMA) and acrylamide (AAm) to the above mixed solution, and then add a crosslinking agent, a chlorination agent to the mixed solution The lithium aqueous solution and the initiator obtain a prepolymer solution;

(3) Pour the prepolymerized solution into a reaction mold after stirring for a period of time, and place the reaction mold in an oven for polymerization to obtain a stretchable, compressible, and freeze-resistant organic hydrogel.

Preferably, the amount of soybean protein isolate described in step (1) is 5-20% of the total mass of the monomer, and further preferably, the amount of soybean protein isolate is 10-15% of the total mass of the monomer; soybean protein isolate is not a monomer , no chemical reaction occurs, because soybean protein will be negatively charged after dispersing in water, and then attracted by positively charged groups on the polymer chain, its role is to improve mechanical properties, dissipate energy in the process of strain, and improve fatigue resistance. ; When the amount of soybean protein isolate is less than 5% of the total monomer mass, the effect is not obvious, and when the amount is higher than 20%, hydrogel cannot be formed.

Preferably, the solvent described in step (1) is a mixture of dimethyl sulfoxide (DMSO) and water, and the mass ratio of DMSO and water is (2-4): (6-8); further preferably, DMSO and The mass ratio of water is 3:7, and the addition of DMSO to the solvent can improve the low temperature resistance of the hydrogel to a certain extent.

Preferably, the solvent quality in step (1) is 70-90% of the total mass of the hydrogel, and further preferably, the solvent quality is 75-85% of the total mass of the hydrogel.

Preferably, in step (1), the heating temperature is set to 85-95°C, and the stirring time is 1.5-2.5h; more preferably, the heating temperature is set to 90°C, and the stirring time is 2h, and the solubility of soybean protein isolate at room temperature is relatively high. Low, soy protein isolate is more soluble under the condition of heating at 90°C and stirring.

Preferably, the mass ratio of the two monomers in step (2) is: SBMA:AAm=1:(1-8).

Preferably, in step (2), the crosslinking agent is N,N-methylenebisacrylamide (MBA), and the amount of the crosslinking agent is 0.1-0.3% of the total mass of the monomers. Further preferably, the amount of the crosslinking agent is 0.2% of the total mass of monomers.

Preferably, the concentration of the lithium chloride aqueous solution is 0.5-2.5 mol·L ^-1 .

Preferably, the initiator is one of ammonium persulfate and azobisisobutyramidine hydrochloride (AIBA), and the amount of the initiator is 1.4-2.8% of the total mass of the monomer. The initiator is ammonium persulfate.

Preferably, the stirring time in step (3) is 20-60 minutes, and further preferably, the stirring time is 30 minutes.

Preferably, in step (3), the polymerization reaction time is 12-24h, and the polymerization temperature is 40-50°C. Further preferably, the reaction time is 12h and the polymerization temperature is 40°C.

Preferably, the Young's modulus of the hydrogel electrolyte is 1-20 kPa, and more preferably, the Young's modulus is 18.4 kPa.

Preferably, the toughness of the hydrogel electrolyte is 0.038-0.242 MJ·m ^-3 , and more preferably, the toughness is 0.2 MJ·m ^-3 .

Preferably, the conductivity of the hydrogel electrolyte at 20°C is 20-40 mS·cm ^-1 , and further preferably, the conductivity of the hydrogel electrolyte at 20°C is 21-37.5 mS·cm ^-1 .

Preferably, the tensile strain of the hydrogel electrolyte that can restore the initial state is 100-600%.

Preferably, the hydrogel electrolyte undergoes 1 to 30 stretching cycles with a strain of 500%, the strain can still be restored to the original length, and the tensile stress is 26.85 kPa.

Preferably, when the compressive strain of the hydrogel electrolyte is 20-80%, the stress is 7.6-480 kPa, and the strain can be restored to the original state.

Preferably, the hydrogel electrolyte is subjected to 30 continuous compression cycles with a strain of 80%, the strain can be restored to the original state, and the compressive stress is 355kPa.

Preferably, the hydrogel electrolyte produces a small strain with an elongation rate of 3%-9%, a resistance change rate of 1.2%-3.3%, a medium strain with an elongation rate of 25%-75%, and a resistance change rate is 13.5%-35%, resulting in large strain with elongation of 300%-500%, and resistance change rate of 165%-355%, so the hydrogel electrolyte has good strain sensitivity and wide sensing window , can be used as sensor material.

Preferably, the resistance change rate of the hydrogel electrolyte after 500 100% stretching cycles is 98%, so the organic hydrogel electrolyte has stable stretching sensing performance.

Preferably, when the compression pressure of the hydrogel electrolyte is 0-68 kPa, the resistance change rate is 0-43%; further preferably, when the compression pressure is p kPa (p is 2, 3.5, 5, 12, 23 , 40, 68), when the compression time is 5 to 10s, the corresponding resistance change rate is r% (r is -11, -19, -23, -33, -38, -41, -43), so the above The hydrogel electrolyte exhibits stable compressive sensing performance.

The application of the above organic hydrogel electrolyte is characterized in that it is used for supercapacitor electrolyte materials and sensor materials.

One or more technical solutions provided by the embodiments of the present invention have at least the following technical effects:

1. The maximum breaking strain of a stretchable, compressible, and freeze-resistant organic hydrogel electrolyte of the present invention can reach 762.5%, and the tensile strain that can be restored to the initial state is 100-600%, and the strain is 80 after 30 times. % of continuous compression cycles, the strain can still be restored to the original state, so the hydrogel electrolyte has excellent mechanical properties and can achieve the effect of flexibility as an electrolyte material for supercapacitors.

2. The room temperature conductivity of a stretchable, compressible and antifreeze organic hydrogel electrolyte of the present invention can reach 37.5mS·cm ^-1 , and the CV curve of the supercapacitor composed of it is in the range of 20-500mV·s ^-1 It can maintain a regular rectangle within the scan rate range of 100°C, and has good reversibility and rate performance; at -20 °C, the charge and discharge time is still 13s, so it has good low-temperature electrical properties, and can realize the use of hydrogel electrolyte as a Technical effects of supercapacitor electrolytes.

3. A stretchable, compressible, and antifreeze organic hydrogel electrolyte of the present invention has significant resistance changes under different strains, has strain sensitivity, and still has a resistance signal after 500 100% stretching cycles, which can achieve Technical effects of hydrogel electrolytes as stable sensor materials.

Description of drawings

Fig. 1 is the stretching cycle curves of the S ₁ A ₄ organohydrogel with different strains (150%, 300%, 450%, 600%) in the present invention.

Figure 2 is a drawing cycle curve of the S ₁ A ₄ organohydrogel at 500% strain in the present invention.

Figure 3 is the compression cycle curves of the S ₁ A ₄ organohydrogel electrolyte with different strains (20%, 40%, 60%, 80%) in the present invention.

Figure 4 is the 30 compression cycle curves of the S ₁ A ₄ organohydrogel electrolyte at 80% strain in the present invention.

FIG. 5 is a curve of the resistance of the S ₁ A ₄ organic hydrogel electrolyte as a function of strain in the present invention.

Figure 6 shows the resistance change of the S ₁ A ₄ organohydrogel electrolyte under small strain in the present invention.

Figure 7 shows the resistance change of the S ₁ A ₄ organohydrogel electrolyte in the present invention under moderate strain.

Figure 8 shows the resistance change of the S ₁ A ₄ organohydrogel electrolyte under large strain in the present invention.

Figure 9 is the resistance change of the S ₁ A ₄ organohydrogel electrolyte in the present invention for 500 stretching cycles at 100% strain.

Figure 10 shows the resistance of the S ₁ A ₄ organohydrogel electrolyte in the present invention as a function of continuously applied pressure.

Figure 11 shows the relative resistance change and pressure sensitivity of the S ₁ A ₄ organohydrogel sensor in the present invention under different pressures.

Figure 12 is the CV curves of different scan rates of the S ₁ A ₄ electrolyte-based supercapacitor in the present invention.

Figure 13 is the GCD curves of different current densities of the S ₁ A ₄ electrolyte-based supercapacitor in the present invention.

Detailed ways

The present invention will be further described below in conjunction with specific embodiments, but not limited thereto.

It should be noted that the experimental methods described in the following examples are conventional methods unless otherwise specified; the reagents, materials and equipment can be obtained from commercial sources unless otherwise specified. Acrylamide, methacryloylethylsulfobetaine, ammonium persulfate, lithium chloride, N,N-methylenebisacrylamide used in the examples of the present invention were purchased from Aladdin Company, soybean protein isolate, Polyvinylidene fluoride was purchased from McLean Company, activated carbon (YP-50F) was purchased from Kuraray, Japan, and acetylene black was purchased from Hefei Kejing.

Glossary:

S ₁ A ₁ , S ₁ A ₄ , S ₁ A ₈ , S ₁ A ₀ , S ₀ A ₁ correspond to the mass ratios of SBMA to acrylamide of 1:1, 1:4, 1:8, 1:0, 0:1 organohydrogel electrolyte.

Methacryloylethylsulfobetaine is abbreviated as SBMA and acrylamide is abbreviated as AAm.

Mechanical properties testing of hydrogel electrolytes:

The tensile test of the hydrogel electrolyte was carried out using a universal testing machine (Hensgrand, WDW-02, China); the tensile speed was 100 mm·min ⁻¹ , and the tensile strain (ε) was defined as ε=(ll ₀ ) /l ₀ ×100%, l ₀ is the original length, l is the length after stretching; the stress calculation formula is σ=F/πR ² ; Young's modulus is the slope of the stretching curve in the range of 0-50%; toughness It is obtained by integrating the area contained in the stress-strain curve, and the unit is MJ·m ^-3 .

The tensile cycle test is to use the same length of the sample to test at a tensile speed of 100mm·min ^-1 , and the maximum strain of the tensile cycle is 500%;

The compression test was carried out using a cylindrical sample with a length of 1 cm, the compression speed was 20 mm·min ^-1 , and the strain ranged from 20% to 80%.

Conductivity test:

The resistance is obtained by sandwiching the hydrogel electrolyte between two stainless steel sheets, and using an electrochemical workstation in the temperature range of -20-25°C, under the conditions of a frequency of 0.1-1MHz and an amplitude of 5mV, through signal detection; The samples were stabilized at the test temperature for 30 minutes prior to measurement. The formula for ionic conductivity (σ) is σ=L/RS, where R is the resistance, S is the cross-sectional area of the hydrogel electrolyte, and L is the thickness of the hydrogel electrolyte.

The room temperature mentioned in the examples refers to 20°C.

Example 1

A stretchable, compressible, antifreeze organic hydrogel electrolyte S ₁ A ₄ and a preparation method thereof, the hydrogel electrolyte S ₁ A ₄ comprises the following components in mass fractions:

Soy protein isolate 2.0%, SBMA 2.7%, AAm 10.9%, MBA 0.027%, lithium chloride 6.55%, ammonium persulfate 0.027%, the balance is DMSO and water, and the mass ratio of DMSO and water is 3:7. The mechanical and electrical properties of the S ₁ A ₄ hydrogel are shown in Table 1.

The preparation method of hydrogel electrolyte S ₁ A ₄ comprises the following steps:

a. Add 0.225g of soybean protein isolate, 2.55g of DMSO and 5.95g of water into a 20mL glass bottle, and place the glass bottle in a 90°C constant temperature water bath and stir for 2h;

b. Add SBMA and acrylamide in a mass ratio of 1:4 (total amount is 1.5g) into a glass bottle, then add 0.003g of MBA, 0.72g of lithium chloride, 0.0225g of ammonium persulfate, and stir magnetically for 30min to obtain The reaction solution;

c. Pour the reaction solution into a glass tube mold with an inner diameter of 6 mm, and place the mold in a 40° C. oven for polymerization for 12 hours to obtain S ₁ A ₄ hydrogel.

Example 2

A stretchable, compressible, antifreeze organic hydrogel electrolyte S ₁ A ₁ and a preparation method thereof, the hydrogel electrolyte S ₁ A ₁ , comprising the following components in mass fractions:

Soy protein isolate 2.0%, SBMA 6.8%, AAm 6.8%, MBA 0.027%, lithium chloride 6.55%, ammonium persulfate 0.027%, the balance is DMSO and water, and the mass ratio of DMSO and water is 3:7. The mechanical and electrical properties of the S ₁ A ₁ hydrogel are shown in Table 1.

The preparation method of the hydrogel electrolyte S ₁ A ₁ is the same as that in Example 1, except that the mass ratio of SBMA to AAm is 1:1.

Example 3

A stretchable, compressible, and antifreeze organic hydrogel electrolyte S ₁ A ₈ and a preparation method thereof, the hydrogel electrolyte S ₁ A ₈ , comprising the following components by mass fraction:

Soy protein isolate 2.0%, SBMA 1.52%, AAm 12.1%, MBA 0.027%, lithium chloride 6.55%, ammonium persulfate 0.027%, the balance is DMSO and water, and the mass ratio of DMSO and water is 3:7. The mechanical and electrical properties of the S ₁ A ₈ hydrogel are shown in Table 1.

The preparation method of the hydrogel electrolyte S ₁ A ₈ is the same as that in Example 1, except that the mass ratio of SBMA to AAm is 1:8.

Example 4

A stretchable, compressible, antifreeze organic hydrogel electrolyte S ₁ A ₀ and a preparation method thereof, the hydrogel electrolyte S ₁ A ₀ , comprising the following components in mass fractions:

Soy protein isolate 2.0%, SBMA 13.6%, MBA 0.027%, lithium chloride 6.55%, ammonium persulfate 0.027%, the balance is DMSO and water, and the mass ratio of DMSO and water is 3:7. The mechanical and electrical properties of the S ₁ A ₀ hydrogel are shown in Table 1.

The preparation method of the hydrogel electrolyte S ₁ A ₀ is the same as that of Example 1, except that AAm is not added.

Example 5

A stretchable, compressible, antifreeze organic hydrogel electrolyte S ₀ A ₁ and a preparation method thereof, the hydrogel electrolyte S ₀ A ₁ comprises the following components by mass fraction:

Soy protein isolate 2.0%, AAm 13.6%, MBA 0.027%, lithium chloride 6.55%, ammonium persulfate 0.027%, the balance is DMSO and water, and the mass ratio of DMSO and water is 3:7. The mechanical and electrical properties of the S ₀ A ₁ hydrogel are shown in Table 1.

The preparation method of the hydrogel electrolyte S ₀ A ₁ is the same as that in Example 1, except that SBMA is not added.

Example 6

A preparation method of a stretchable, compressible and antifreeze organic hydrogel electrolyte, comprising the following steps:

a. Add 0.225g of soybean protein isolate, 2.55g of DMSO and 5.95g of water into a 20mL glass bottle, and place the glass bottle in a constant temperature water bath at 90°C and stir for 2h;

b. Add SBMA and acrylamide in a mass ratio of 1:4 (total amount is 1.5 g) into a glass bottle, then add 0.003 g of MBA, 0.72 g of lithium chloride, 0.003 g of ammonium persulfate, and stir magnetically for 30 min to obtain The reaction solution;

c. Pour the reaction solution into a glass tube mold with an inner diameter of 6 mm, and place the mold in a 40° C. oven for polymerization for 12 hours to obtain S ₁ A ₄ hydrogel. The mechanical and electrical properties of the S ₁ A ₄ hydrogel are shown in Table 1.

Table 1. Mass fractions and mechanical and electrical properties of hydrogel components

Example 7

An application of a stretchable and compressible antifreeze organic hydrogel electrolyte, which is applied to the preparation of supercapacitors, and the preparation steps include:

(1) Preparation of electrodes

Activated carbon (YP-50F), acetylene black and PVDF were weighed according to 80%, 10% and 10% of the total mass respectively, then ground in an agate mortar for 2 hours, and 1 g of dispersant NMP (N-methylpyrrolidone) was added and stirred. Mix it into a uniform slurry; spread the slurry evenly on the carbon cloth, and dry it in a vacuum oven at 80°C until the dispersant is fully removed, and the active material content on each electrode is about 2.2 mg.

(2) Supercapacitor assembly: The supercapacitor can be assembled by sandwiching the organic hydrogel S ₁ A ₄ prepared in Example 1 between two electrodes.

The obtained supercapacitor has good reversibility and excellent rate performance (as shown in Figure 12), good electric double layer behavior (as shown in Figure 13), and the resistance is 5Ω at 20 °C, and the resistance gradually increases with the decrease of temperature. big. At -20°C, the resistance is 18Ω.

As shown in Figure 1, the prepared organohydrogel electrolyte not only has good strength and toughness, but also has anti-fatigue properties. In order to test its fatigue resistance, stretching cycles with different strains (150%, 300%, 450%, 600%) were first carried out. Even if stretched to 600% strain, the S ₁ A ₄ gel electrolyte can also recover to the original state. state.

As shown in Fig. 2, to further investigate its fatigue resistance, 30 stretching cycles with a strain of 500% _were carried out with the _S1A4 gel electrolyte. It can be seen that the stress decreased slightly from 31kPa to 29kPa after 5 stretching cycles. But after 30 cycles, the stress of the S ₁ A ₄ gel remained at a high level, and the strain could still recover to the original length. This indicates that the S ₁ A ₄ gel has satisfactory self-recovery properties.

As shown in Fig. ₃ , the fatigue resistance of the _S1A4 organohydrogel was further investigated by compression cycling. Compression cycling tests at different strains were first performed. As the compressive strain increases, its stress gradually increases, and at 80% compressive strain, its stress is 480kPa. Meanwhile, it can still recover to the original state even if the strain is a large strain of 80%.

As shown in Fig. 4, to further characterize its compression cycle performance, it was subjected to 30 consecutive compression cycles. It can be seen that during the fifth compression cycle, although the stress decreases from 480kPa to 400kPa, it can still recover to the original strain. After the 30th cycle, it can be seen that the stress-strain curves of multiple compression cycles are basically coincident. This shows that the _{S1A4 organohydrogel} electrolyte has good anti-fatigue performance, which ensures the adaptability of the _{S1A4 organohydrogel} electrolyte to different working environments and expands the application range.

Since the _S1A4 organic hydrogel electrolyte has good ionic conductivity, it can be used as a sensor material. As shown in Figure ₅ , the resistance of the _S1A4 organic hydrogel electrolyte is gradually increased with the increase of the strain _. get bigger.

As shown in Fig. 6, Fig. 7, Fig. 8, the S ₁ A ₄ organohydrogel electrolyte was tested at small strain (3%, 6%, 9%), medium strain (25%, 50%, 75%) and Resistance change at large strain (300%, 400%, 500%). In the case of small strain, when the S ₁ A ₄ organohydrogel electrolyte is stretched by 3%, 6%, and 9%, the resistance changes are 1.2%, 2.4%, and 3.3%, respectively (Fig. 6). In the case of medium strain, when the S ₁ A ₄ organohydrogel electrolyte is stretched by 25%, 50%, and 75%, the resistance changes are 13.5%, 24.5%, and 35%, respectively (Fig. 7). Under large strain, the resistance changes of S ₁ A ₄ organohydrogel electrolytes are 165%, 251%, and 355% when stretched by 300%, 400%, and 500%, respectively (Fig. 8). This illustrates the strain sensitivity and broad sensing window of the _{S1A4 organohydrogel} electrolyte.

As shown in Fig. ₉ , to verify the stability of the _S1A4 organohydrogel electrolyte sensor, 500 100% stretching cycles were performed. It can be seen that with the increase of the number of cycles, the resistance slightly increases, but there is no loss of resistance signal, indicating that the S ₁ A ₄ organohydrogel electrolyte sensor has stability.

As shown in Fig. ₁₀ , since the _S1A4 organohydrogel has good compressive properties and self-recovery ability, it is a good material for the preparation of compressive sensors. The resistance changes of the _{S1A4 organohydrogels} under different pressures were first tested. It can be seen that with increasing compressive pressure, the resistance change gradually decreases due to the shortening of the ion transport pathway. When the pressure is kept constant, the resistance remains basically unchanged, which indicates the stability of the S ₁ A ₄ organohydrogel.

As shown in FIG. 11 , the pressure sensitivity of the pressure sensor represents the slope of the relative resistance change on the voltage transformation curve, that is, the relative resistance change rate. It can be seen that the pressure sensitivity can be divided into different stages and the pressure sensitivity gradually decreases as the pressure increases.

Claims (12)

1. the preparation method of stretchable, compressible, antifreeze organic hydrogel electrolyte, is characterized in that, step is as follows: (1) Add soybean protein isolate and solvent into the reaction vessel, heat and stir to obtain a mixed solution; (2) adding two monomers, methacryloylethylsulfobetaine and acrylamide, to the above mixed solution, and then adding a crosslinking agent, an aqueous lithium chloride solution and an initiator to the mixed solution to obtain a prepolymerization solution; (3) After stirring the prepolymerized liquid evenly, pour it into a reaction mold for constant temperature reaction to obtain a stretchable, compressible and antifreeze organic hydrogel; The solvent described in the step (1) is a mixture of dimethyl sulfoxide and water, and the mass ratio of the dimethyl sulfoxide and water is (2-4): (6-8); The mass ratio of the two monomers described in step (2) is: methacryloylethylsulfobetaine:acrylamide=1:(1~8); the initiator dosage is 1.4% of the total mass of the monomers -2.8%, the amount of crosslinking agent is 0.1-0.3% of the total mass of the monomer. 2 . The method for preparing a stretchable, compressible, and antifreeze organic hydrogel electrolyte according to claim 1 , wherein the amount of soybean protein isolate described in step (1) is 5-5% of the total monomer mass. 3 . 20%, and the quality of the solvent is 70-90% of the total mass of the hydrogel. 3 . The method for preparing a stretchable, compressible, and freeze-resistant organic hydrogel electrolyte according to claim 2 , wherein the amount of soybean protein isolate described in step (1) is 10-10% of the total monomer mass. 4 . 15%. 4. The method for preparing a stretchable, compressible, and antifreeze organic hydrogel electrolyte according to claim 1, wherein the crosslinking agent in step (2) is N,N-methylenebis Acrylamide; the concentration of the lithium chloride aqueous solution is 0.5-2.5 mol·L ^-1 . 5. The method for preparing a stretchable, compressible, and antifreeze organic hydrogel electrolyte according to claim 1, wherein the initiator in step (2) is ammonium persulfate, azobisisobutylene One of the amidine hydrochlorides. 6 . The method for preparing a stretchable, compressible, and antifreeze organic hydrogel electrolyte according to claim 5 , wherein the initiator is ammonium persulfate. 7 . 7 . The method for preparing a stretchable, compressible, and freeze-resistant organic hydrogel electrolyte according to claim 1 , wherein the temperature in step (1) is set to 85-95° C., and the stirring time is 1.5-2.5° C. 8 . h; in step (3), the stirring time is 20-60 minutes, the polymerization reaction time is 12-24 h, and the reaction temperature is 40-50°C. 8. The stretchable, compressible, antifreeze organic hydrogel electrolyte prepared by the method according to any one of claims 1-7, wherein the Young's modulus of the hydrogel electrolyte is 1～20kPa , the toughness is 0.038-0.242MJ·m ^-3 . 9 . The stretchable, compressible, and freeze-resistant organic hydrogel electrolyte according to claim 8 , wherein the conductivity of the hydrogel electrolyte at 20° C. is 20-40 mS·cm ⁻¹ . 10 . 10 . The stretchable, compressible, and antifreeze organic hydrogel electrolyte according to claim 9 , wherein the conductivity of the hydrogel electrolyte at 20° C. is 21-37.5 mS·cm ⁻¹ . . 11. The stretchable, compressible, and freeze-resistant organic hydrogel electrolyte according to claim 9, wherein the resistance change rate of the hydrogel electrolyte after 500 100% stretching cycles is 90-100 %; The hydrogel electrolyte produces a small strain with an elongation rate of 3% to 9%, a resistance change rate of 1.2% to 3.3%, a medium strain with an elongation rate of 25% to 75%, and a resistance change rate of 13.5%. ~35%, resulting in a large strain with an elongation of 300% to 500%, and a resistance change rate of 165% to 355%. 12. The application of the organic hydrogel electrolyte according to claim 11, characterized in that it is used in supercapacitor electrolyte materials and sensor materials.

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