Poly (N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte, preparation method and supercapacitor

Abstract

The invention belongs to the field of electrochemical energy storage, and particularly relates to a poly (N-hydroxypropyl acrylamide) / hydroxypropyl pachymaran / calcium chloride hydrogel-based polymer electrolyte and a flexible integrated supercapacitor. According to the invention, N-hydroxypropyl acrylamide is used as a polymeric monomer, hydroxypropyl pachymaran is used as a reinforcing modifier, calcium chloride is used as an electrolyte, borax is used as a cross-linking agent, and a'redox-initiated polymerization-ultraviolet ozone surface modification-synchronous stretching coating assembly 'process is adopted to prepare the composite material. According to the invention, a synergistic effect is formed by copolymerization crosslinking and ultraviolet ozone surface modification, the mechanical property of a GPE body is guaranteed by copolymerization crosslinking, the interface adhesion force is synchronously improved by surface modification, the two parts are adapted in the whole process from network construction to interface optimization, and the mechanical strength and the adhesion property are synchronously improved in mechanism.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical energy storage, specifically relating to a poly(N-hydroxypropylacrylamide / hydroxypropyl poria cocos polysaccharide / calcium chloride) hydrogel-based polymer electrolyte and a flexible integrated supercapacitor. Background Technology

[0002] With the rapid development of wearable electronics and flexible energy storage devices, flexible supercapacitors (SC) have become a key research and development area due to their advantages such as high power density and fast charging and discharging speed. As the core component of SC, polymer electrolytes (GPE) must simultaneously meet the requirements of mechanical strength, freeze resistance, interfacial adhesion, and electrochemical stability to replace traditional liquid electrolytes (which are prone to leakage and have poor safety).

[0003] There are three major bottlenecks in the current research and development of GPE: First, it is difficult to balance mechanical strength and freeze resistance. Existing hydrogel GPEs are mostly modified with polysaccharides (such as konjac glucomannan and guar gum), but the compatibility of polysaccharides with polymer monomers (such as acrylamide) is limited, easily leading to uneven network structure. If high mechanical strength is desired, the degree of cross-linking needs to be increased, but this reduces the segment flexibility at low temperatures, resulting in conductivity retention of less than 60% at -20℃. Adding polyols to improve freeze resistance weakens the gel's mechanical properties, with tensile strength often less than 1 MPa. Second, poor interfacial bonding restricts the cycling stability of SC. In traditional flexible SC assembly, the bonding between GPE and electrodes / current collectors relies on binders (such as polyvinylidene fluoride), which not only increases interfacial resistance but also restricts the flexible deformation of the SC due to the rigidity of the binder, resulting in capacitance retention of less than 80% after 1000 charge-discharge cycles. A few binder-free solutions achieve bonding through physical pressing, but insufficient interfacial contact easily leads to electrode detachment. Third, the preparation process lacks economic and environmental friendliness. Existing GPE often requires high-temperature polymerization (above 70°C) or complex post-treatment (such as solvent replacement and vacuum annealing), resulting in high energy consumption. Some modification processes rely on reagents such as halogenated alkanes and high-concentration strong bases (such as KOH), which not only corrode equipment but also generate harmful waste liquids, failing to meet the requirements of green production and making it difficult to apply on a large scale.

[0004] In summary, developing GPE and flexible integrated SC with high mechanical strength, excellent freeze resistance, strong interfacial adhesion, and environmentally friendly manufacturing process is a technical problem that urgently needs to be solved in the field of flexible energy storage. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte, its preparation method, and a supercapacitor, solving the problems of difficulty in balancing mechanical strength and freeze resistance in hydrogel-based gel polymer electrolytes (GPE), and weak interfacial bonding and poor cycle stability in flexible supercapacitors (SC).

[0006] This invention is achieved through the following technical solution: A poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte is prepared by reacting N-hydroxypropylacrylamide as a polymer monomer, hydroxypropyl poria cocos polysaccharide as a reinforcing modifier, calcium chloride as an electrolyte, and borax as a crosslinking agent.

[0007] A method for preparing a poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte includes the following steps: S1: Borax is dispersed and dissolved in a binary solvent and then deoxygenated to obtain a crosslinking agent solution; S2: N-hydroxypropylacrylamide, hydroxypropyl poria cocos polysaccharide and calcium chloride are dissolved in water and deoxygenated to obtain a monomer mixture; S3: Add an initiator and a promoter to the monomer mixture in step S2, then add the crosslinking agent solution obtained in step S1, and mix to obtain a reaction precursor solution; S4: The reaction precursor liquid is injected into the mold and polymerized at 50℃-60℃. After the reaction is completed, the mold is removed to obtain the polymer electrolyte primary product. The polymer electrolyte primary product is subjected to ultraviolet ozone treatment to obtain poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte.

[0008] Preferably, the binary solvent is a mixture of glycerol and water in a mass ratio of 2:8.

[0009] Preferably, the mass ratio of borax to N-hydroxypropylacrylamide is 0.04-0.064:4.0.

[0010] Preferably, the mass ratio of N-hydroxypropylacrylamide, hydroxypropyl poria cocos polysaccharide and calcium chloride is 4.0:0.08-0.10:0.735-0.98.

[0011] Preferably, in step S3, the initiator is ammonium persulfate and the promoter is N,N,N',N'-tetramethylethylenediamine.

[0012] Preferably, the polymer electrolyte precursor is subjected to ultraviolet ozone treatment with a treatment power of 100W-150W and a treatment time of 3-10 minutes.

[0013] A flexible integrated supercapacitor includes a poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte, electrode materials, and a current collector; Preferred, including: The polymer electrolyte is stretched and fixed in both the transverse and longitudinal directions; Electrode active material is coated on both sides of the polymer electrolyte in a stretched state; The polymer electrolyte coated with electrode active material is restored to a relaxed state; A flexible integrated supercapacitor is obtained by pressing and assembling a current collector with a polymer electrolyte loaded with electrode active materials.

[0014] Preferably, the electrode active material is activated carbon; the current collector is made of carbon nanotubes or polyester composite fabric.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: This invention uses N-hydroxypropylacrylamide (HPAA) as the polymer monomer, hydroxypropyl pachymansia polysaccharide (HPP) as the reinforcing modifier, calcium chloride (CaCl2) as the electrolyte, and borax as the crosslinking agent. It is prepared using a process of "redox-initiated polymerization - ultraviolet ozone surface modification - synchronous stretching coating assembly": First, HPAA and HPP are copolymerized through an APS-TEMEDredox system, and a hydrogel network is constructed by dynamic crosslinking with borax; then, the surface properties of GPE are optimized by ultraviolet ozone treatment; finally, an integrated SC is assembled by stretching and fixing coating, so as to achieve a tight bond between GPE and electrodes and current collectors. The results show that the HPAA / HPP / CaCl2 hydrogel GPE prepared by this invention has a tensile strength of 1.4-1.7 MPa, an elongation at break of 480%-550%, and a conductivity retention rate of 79%-85% at -20℃. The SC based on this GPE has a capacitance retention rate of 91%-95% after 1000 charge-discharge cycles, and a rate performance (1A / g / 0.1A / g) of 0.79-0.83. The comprehensive performance is far superior to products without polysaccharide components or traditional material systems, providing a new direction for the high performance of flexible energy storage devices. It achieves synergistic regulation of polymerization enhancement and interface modification, breaking the step-by-step limitation of "polymerization first and modification later" in traditional processes. Traditional processes are prone to damaging the hydrogel network structure due to subsequent modification, or resulting in insufficient interfacial bonding. However, in this invention, the copolymerization of HPP and HPAA, dynamic crosslinking of borax, and surface modification by ultraviolet ozone form a synergistic effect. Copolymerization and crosslinking ensure the mechanical properties of the GPE matrix, while surface modification simultaneously improves interfacial adhesion. The two are fully compatible from network construction to interface optimization, achieving a simultaneous improvement in mechanical strength and adhesion performance from a mechanistic perspective.

[0016] The process mechanism of this invention is better suited to the low-temperature and cycling requirements of flexible SC. Traditional hydrogel GPEs often suffer from poor compatibility between electrolytes and polysaccharides, leading to a sharp drop in conductivity at low temperatures; or due to improper cross-linking, electrode detachment is prone to occur during SC cycling. In this invention, the coordination effect between CaCl2 and HPP hydroxyl groups can inhibit ice crystal growth at low temperatures, ensuring stable conductivity at -20℃; at the same time, the dynamic borax cross-linking network has both elasticity and stability, and combined with the stretch coating process, it enables the electrode and GPE to form an "elastic interlocking" structure, effectively avoiding interfacial peeling during cycling, and exhibiting electrochemical stability superior to traditional rigid bonding systems.

[0017] The economic and environmental benefits of this invention are significantly optimized through process simplification. Existing technologies often require complex post-treatment (such as solvent displacement and high-temperature annealing) to improve GPE performance, or rely on toxic modifiers (such as haloalkanes) to improve the interface, increasing costs and pollution risks. The HPAA, HPP, and CaCl2 used in this invention are all low-toxicity and readily available raw materials. Redox initiation does not require high temperatures, and UV ozone modification does not require chemical reagents. Furthermore, the post-treatment of the product only requires simple cutting and pressing, reducing energy consumption and pollutant emissions from the source of the process. At the same time, the raw material reaction efficiency is high, and there is no need for excessive addition, which greatly reduces production costs and is more suitable for large-scale mass production. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Components in the embodiments of the present invention can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0019] To achieve the above objectives, this invention uses N-hydroxypropylacrylamide (HPAA) as the polymer monomer, hydroxypropyl pachymansia polysaccharide (HPP) as the reinforcing modifier, calcium chloride (CaCl2) as the electrolyte, and borax as the crosslinking agent. It employs a "redox-initiated polymerization-UV ozone surface modification-synchronous stretch coating assembly" process: first, HPAA and HPP are copolymerized using an APS-TEMEDredox system, and a hydrogel network is constructed by dynamic crosslinking with borax; then, the surface properties of the GPE are optimized through UV ozone treatment; finally, an integrated SC is assembled using a stretch-fixed coating method, achieving a tight bond between the GPE and the electrodes and current collectors. The results show that the HPAA / HPP / CaCl2 hydrogel GPE prepared in this invention has a tensile strength of 1.4-1.7 MPa, an elongation at break of 480%-550%, and a conductivity retention rate of 79%-85% at -20℃. The SC based on this GPE retains 91%-95% of its capacitance after 1000 charge-discharge cycles, and its rate performance (1A / g / 0.1A / g) is 0.79-0.83. Its comprehensive performance far exceeds that of products without polysaccharide components or traditional material systems, providing a new direction for the high-performance development of flexible energy storage devices. The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1: Step 1: Mix glycerol (2.0g) and distilled water (8.0g) at a mass ratio of 2:8 to obtain 10.0g of glycerol-water binary solvent; add borax (0.04g) to the solvent, place it in an ultrasonic cleaner (power 300W, temperature 25℃) and ultrasonically disperse for 15min, then transfer it to a magnetic stirrer (speed 150r / min) and stir at room temperature for 20min until completely dissolved; then purge with nitrogen gas (flow rate 18mL / min) to remove oxygen for 30min to obtain borax-glycerol-water mixture, seal and store for later use.

[0021] Step 2: Weigh 4.0g HPAA, 0.08g HPP, and 0.735g CaCl2, and add 9.0g distilled water; place the mixture in a temperature-controlled magnetic stirrer, set the temperature to 30℃ and the speed to 200r / min, and stir for 45min until the solid is completely dissolved; purge with nitrogen (flow rate 18mL / min) to remove oxygen for 30min to obtain a monomer-polysaccharide-electrolyte mixture.

[0022] Step 3: Add 20 mg of ammonium persulfate (APS) to the deoxygenated monomer-polysaccharide-electrolyte mixture obtained in Step 2 and stir magnetically for 1 min until dissolved; then add 5 μL of N,N,N',N'-tetramethylethylenediamine (TEMED) and continue stirring for 2 min; subsequently, slowly inject the borax-glycerol-water mixture obtained in Step 1 at a dropping rate of 1.5 mL / min while stirring (120 r / min). After the addition is complete, continue stirring for 5 min to obtain the reaction precursor solution (wherein: HPP concentration is 0.8 wt% of its total mass with the glycerol-water binary solvent, the mass ratio of borax to HPP is 1:2, and the CaCl2 concentration is 1.5 mol / L).

[0023] Step 4: Inject the precursor solution into a glass mold with a 2.5mm gap, seal it, and place it in a constant temperature water bath. Set the temperature to 55℃ and polymerize for 8 hours. After the reaction is complete, allow it to cool naturally to room temperature and demold to obtain the initial product of HPAA / HPP / CaCl2 hydrogel GPE, which is poly(N-hydroxypropylacrylamide) hydrogel-based gel polymer electrolyte.

[0024] Step 5: Place the initial GPE sample in an ultraviolet ozone treatment instrument, set the power to 120W and the treatment time to 5min to improve the surface hydrophilicity and roughness; fix the modified GPE with a stretch ratio of 1.3 times in both the transverse and longitudinal directions, and evenly coat both sides of the GPE with activated carbon (coating amount 9mg / cm²), and let it stand for 13min to allow the GPE to recover its relaxed state; cut the GPE into strips of 5×1.2cm with a blade, attach carbon nanotubes (current collectors) of matching size to both ends, and press them together with a flat plate press (pressure 0.3MPa) for 30s to ensure tight adhesion; place the assembled SC in a constant temperature and humidity chamber (temperature 25℃, relative humidity 60%), store it in the dark, and obtain a flexible integrated supercapacitor; Example 2: Step 1: Mix glycerol (2.0g) and distilled water (8.0g) at a mass ratio of 2:8 to obtain 10.0g of glycerol-water binary solvent; add borax (0.04g) to the solvent, place it in an ultrasonic cleaner (power 300W, temperature 25℃) and ultrasonically disperse for 15min, then transfer it to a magnetic stirrer (speed 150r / min) and stir at room temperature for 20min until completely dissolved; then purge with nitrogen gas (flow rate 18mL / min) to remove oxygen for 30min to obtain borax-glycerol-water mixture, seal and store for later use.

[0025] Step 2: Weigh 4.0g HPAA, 0.10g HPP, and 0.735g CaCl2, and add 9.0g distilled water; place the mixture in a temperature-controlled magnetic stirrer, set the temperature to 30℃ and the speed to 200r / min, and stir for 45min until the solid is completely dissolved; purge with nitrogen (flow rate 18mL / min) to remove oxygen for 30min to obtain a monomer-polysaccharide-electrolyte mixture.

[0026] Step 3: Add 20 mg of ammonium persulfate (APS) to the deoxygenated monomer-polysaccharide-electrolyte mixture obtained in Step 2 and stir magnetically for 1 min until dissolved; then add 5 μL of N,N,N',N'-tetramethylethylenediamine (TEMED) and continue stirring for 2 min; subsequently, slowly inject the borax-glycerol-water mixture obtained in Step 1 at a dropping rate of 1.5 mL / min while stirring (120 r / min). After the addition is complete, continue stirring for 5 min to obtain the reaction precursor solution (wherein: HPP concentration is 0.8 wt% of its total mass with the glycerol-water binary solvent, the mass ratio of borax to HPP is 1:2, and the CaCl2 concentration is 1.5 mol / L).

[0027] Step 4: Inject the precursor solution into a glass mold with a 2.5mm gap, seal it, and place it in a constant temperature water bath. Set the temperature to 55℃ and polymerize for 8 hours. After the reaction is complete, allow it to cool naturally to room temperature and demold to obtain the initial product of HPAA / HPP / CaCl2 hydrogel GPE, which is poly(N-hydroxypropylacrylamide) hydrogel-based gel polymer electrolyte.

[0028] Step 5: Place the initial GPE sample in an ultraviolet ozone treatment instrument, set the power to 120W and the treatment time to 5min to improve the surface hydrophilicity and roughness; fix the modified GPE with a stretch ratio of 1.3 times in both the transverse and longitudinal directions, and evenly coat both sides of the GPE with activated carbon (coating amount 9mg / cm²), and let it stand for 13min to allow the GPE to recover its relaxed state; cut the GPE into strips of 5×1.2cm with a blade, attach carbon nanotubes (current collectors) of matching size to both ends, and press them together with a flat plate press (pressure 0.3MPa) for 30s to ensure tight adhesion; place the assembled SC in a constant temperature and humidity chamber (temperature 25℃, relative humidity 60%), store it in the dark, and obtain a flexible integrated supercapacitor; The preparation process of Example 2 is exactly the same as that of Example 1, except that the amount of HPP in step 2 is adjusted to 0.10g. The other steps and parameters are exactly the same as those of Example 1.

[0029] Example 3: Step 1: Mix glycerol (2.0g) and distilled water (8.0g) at a mass ratio of 2:8 to obtain 10.0g of glycerol-water binary solvent; add borax (0.04g) to the solvent, place it in an ultrasonic cleaner (power 300W, temperature 25℃) and ultrasonically disperse for 15min, then transfer it to a magnetic stirrer (speed 150r / min) and stir at room temperature for 20min until completely dissolved; then purge with nitrogen gas (flow rate 18mL / min) to remove oxygen for 30min to obtain borax-glycerol-water mixture, seal and store for later use.

[0030] Step 2: Weigh 4.0g HPAA, 0.10g HPP, and 0.98g CaCl2, and add 9.0g distilled water; place the mixture in a temperature-controlled magnetic stirrer, set the temperature to 30℃ and the speed to 200r / min, and stir for 45min until the solid is completely dissolved; purge with nitrogen (flow rate 18mL / min) to remove oxygen for 30min to obtain a monomer-polysaccharide-electrolyte mixture.

[0031] Step 3: Add 20 mg of ammonium persulfate (APS) to the deoxygenated monomer-polysaccharide-electrolyte mixture obtained in Step 2 and stir magnetically for 1 min until dissolved; then add 5 μL of N,N,N',N'-tetramethylethylenediamine (TEMED) and continue stirring for 2 min; subsequently, slowly inject the borax-glycerol-water mixture obtained in Step 1 at a dropping rate of 1.5 mL / min while stirring (120 r / min). After the addition is complete, continue stirring for 5 min to obtain the reaction precursor solution (wherein: HPP concentration is 0.8 wt% of its total mass with the glycerol-water binary solvent, the mass ratio of borax to HPP is 1:2, and the CaCl2 concentration is 1.5 mol / L).

[0032] Step 4: Inject the precursor solution into a glass mold with a 2.5mm gap, seal it, and place it in a constant temperature water bath. Set the temperature to 55℃ and polymerize for 8 hours. After the reaction is complete, allow it to cool naturally to room temperature and demold to obtain the initial product of HPAA / HPP / CaCl2 hydrogel GPE, which is poly(N-hydroxypropylacrylamide) hydrogel-based gel polymer electrolyte.

[0033] Step 5: Place the initial GPE sample in an ultraviolet ozone treatment instrument, set the power to 120W and the treatment time to 5min to improve the surface hydrophilicity and roughness; fix the modified GPE with a stretch ratio of 1.3 times in both the transverse and longitudinal directions, and evenly coat both sides of the GPE with activated carbon (coating amount 9mg / cm²), and let it stand for 13min to allow the GPE to recover its relaxed state; cut the GPE into strips of 5×1.2cm with a blade, attach carbon nanotubes (current collectors) of matching size to both ends, and press them together with a flat plate press (pressure 0.3MPa) for 30s to ensure tight adhesion; place the assembled SC in a constant temperature and humidity chamber (temperature 25℃, relative humidity 60%), store it in the dark, and obtain a flexible integrated supercapacitor; The preparation process of Example 3 is exactly the same as that of Example 1, except that the amount of CaCl2 in step 2 is adjusted to 0.98g. The other steps and parameters are exactly the same as those of Example 1.

[0034] Example 4: The preparation process of Example 4 is exactly the same as that of Example 1, except that the amount of borax in step 2 is adjusted to 0.064g and the polymerization temperature in step 4 is adjusted to 50℃. The other steps and parameters are exactly the same as those of Example 1.

[0035] Example 5: The preparation process of Example 5 is exactly the same as that of Example 1, except that the amount of borax in step 2 is adjusted to 0.05g, the polymerization temperature in step 4 is adjusted to 60℃, the ultraviolet ozone treatment time in step 5 is adjusted to 10min, and the treatment power is 100W. The other steps and parameters are exactly the same as those of Example 1.

[0036] Example 6: The preparation process of Example 6 is exactly the same as that of Example 1, except that the mass ratio of N-hydroxypropylacrylamide, hydroxypropyl poria cocos polysaccharide and calcium chloride is 4.0:0.09:0.84, the ultraviolet ozone treatment time in step five is adjusted to 7 min, the treatment power is 150 W, and the current collector is made of polyester composite cloth. All other steps and parameters are exactly the same as those in Example 1.

[0037] Comparative Example 1: The preparation process of Example 1 is exactly the same as that of Example 1, except that HPP is not added in step two.

[0038] Comparative Example 2: Following the preparation process of Example 1, only HPP in step two was replaced with hydroxypropyl konjac glucomannan (HPGM, 0.08g), and CaCl2 was replaced with lithium chloride (LiCl, 0.585g, concentration 1.5mol / L). The other steps and parameters were exactly the same as in Example 1, and the final product was named D2.

[0039] Table 1 shows the test data of the gel polymer electrolyte GPE and the supercapacitor SC of the HPAA / HPP / CaCl2 systems prepared in Examples 1-6.

[0040] As shown in Table 1, the overall performance of the HPAA / HPP / CaCl2 system gel polymer electrolyte GPE and supercapacitor SC prepared in Examples 1-6 is significantly better than that of the comparative examples, as detailed below: Mechanical and adhesive properties: Examples 1-6 have tensile strength of 1.4-1.7 MPa, elongation at break of 480%-550%, and adhesive strength of 0.40-0.48 MPa, which are far superior to Comparative Example 1 (without HPP, tensile strength 0.5 MPa, adhesive strength 0.18 MPa), proving that HPP can enhance the network structure through cross-linking, thereby improving mechanical stability and interfacial bonding. Examples 2 (1.0 wt% HPP) and 4 (80% borax) have even better tensile / adhesive properties due to the increased polysaccharide concentration or cross-linking agent.

[0041] Freeze resistance: The conductivity retention rate at -20℃ was 79%-85% in Example 1, only 50% in Comparative Example 1, and 68% in Comparative Example 2 (traditional system), indicating that HPP and CaCl2 synergistically inhibit ice crystal growth and improve low-temperature stability; Example 3 (CaCl2 2.0 mol / L) showed the best freeze resistance due to the increased electrolyte concentration.

[0042] SC electrochemical performance: The cycle capacitance retention rate of the examples was 91%-95% and the rate performance was 0.79-0.83, which was significantly different from that of Comparative Examples 1 (75%, 0.62) and 2 (80%, 0.70); Example 6 (UV 7 min) had the best cycle and adhesion performance due to more complete surface modification and optimized interfacial charge transport.

[0043] In summary, the HPAA / HPP / CaCl2 system and process of this invention can effectively balance mechanical, adhesive, freeze-resistant and electrochemical properties, and are superior to polysaccharide-free or traditional material systems.

[0044] Unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined to form new technical solutions.

[0045] Unless otherwise specified, all the technical features and preferred features mentioned herein can be combined to form new technical solutions.

[0046] In this invention, unless otherwise specified, percentage (%) or parts refer to weight percentage or parts relative to the composition.

[0047] Unless otherwise specified, the components or preferred components involved in this invention can be combined with each other to form new technical solutions.

[0048] In this invention, unless otherwise specified, the numerical range "a~b" represents an abbreviation of any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "6~22" means that all real numbers between "6~22" have been listed in this document, and "6~22" is simply an abbreviation of these numerical combinations.

[0049] The "scope" disclosed in this invention can be in the form of a lower limit and an upper limit, and can be one or more lower limits and one or more upper limits, respectively.

[0050] In this invention, the term "and / or" as used herein refers to any combination of one or more of the associated listed items, as well as all possible combinations, and includes such combinations.

[0051] In this invention, unless otherwise stated, the various reactions or operation steps may be performed sequentially or in a particular order. Preferably, the reaction methods described herein are performed sequentially.

[0052] Unless otherwise stated, the technical and scientific terms used herein have the same meanings as those familiar to those skilled in the art. Furthermore, any methods or materials similar to or equivalent to those described herein may also be used in this invention.

[0053] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Those skilled in the art can readily implement the present invention according to the description and above. However, any modifications, alterations, or variations made by those skilled in the art without departing from the scope of the present invention, based on the disclosed technical content, are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, or variations made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the present invention.

Claims

1. A poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte, characterized in that, include: The product was prepared by reacting N-hydroxypropylacrylamide as the polymer monomer, hydroxypropyl poria cocos polysaccharide as the reinforcing modifier, calcium chloride as the electrolyte, and borax as the crosslinking agent.

2. A method for preparing the poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte as described in claim 1, characterized in that, Includes the following steps: S1: Borax is dispersed and dissolved in a binary solvent and then deoxygenated to obtain a crosslinking agent solution; S2: N-hydroxypropylacrylamide, hydroxypropyl poria cocos polysaccharide and calcium chloride are dissolved in water and deoxygenated to obtain a monomer mixture; S3: Add an initiator and a promoter to the monomer mixture in step S2, then add the crosslinking agent solution obtained in step S1, and mix to obtain a reaction precursor solution; S4: The reaction precursor liquid is injected into the mold and polymerized at 50℃-60℃. After the reaction is completed, the mold is removed to obtain the polymer electrolyte primary product. The polymer electrolyte primary product is subjected to ultraviolet ozone treatment to obtain poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte.

3. The method for preparing the poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte according to claim 1, characterized in that, The binary solvent is a mixture of glycerol and water in a mass ratio of 2:

8.

4. The method for preparing the poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte according to claim 1, characterized in that, The mass ratio of borax to N-hydroxypropylacrylamide is 0.04-0.064:4.

0.

5. The method for preparing the poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte according to claim 1, characterized in that, The mass ratio of N-hydroxypropylacrylamide, hydroxypropyl poria cocos polysaccharide, and calcium chloride is 4.0:0.08-0.10:0.735-0.

98.

6. The method for preparing the poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte according to claim 1, characterized in that, In step S3, the initiator is ammonium persulfate and the promoter is N,N,N',N'-tetramethylethylenediamine.

7. The method for preparing the poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte according to claim 1, characterized in that, The polymer electrolyte sample is subjected to ultraviolet ozone treatment at a power of 100W-150W for 3-10 minutes.

8. A flexible integrated supercapacitor, characterized in that, The invention includes a poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte, an electrode material, and a current collector, wherein the polymer electrolyte is the poly(N-hydroxypropylacrylamide) hydrogel-based polymer electrolyte as described in any one of claims 1, or a hydrogel-based polymer electrolyte prepared by the method described in any one of claims 2-7.

9. The flexible integrated supercapacitor according to claim 8, characterized in that, include: The polymer electrolyte is stretched and fixed in both the transverse and longitudinal directions; Electrode active material is coated on both sides of the polymer electrolyte in a stretched state; The polymer electrolyte coated with electrode active material is restored to a relaxed state; A flexible integrated supercapacitor is obtained by pressing and assembling a current collector with a polymer electrolyte loaded with electrode active materials.

10. The flexible integrated supercapacitor according to claim 8, characterized in that, The electrode active material is activated carbon; the current collector is made of carbon nanotubes or polyester composite fabric.

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