Preparation method of photo-thermal response type polyelectrolyte / conductive polymer interpenetrating network hydrogel

Abstract

The invention discloses a preparation method of photo-thermal response type polyelectrolyte / conductive polymer interpenetrating network hydrogel, which comprises the following steps: 1, dissolving rigid and flexible macromolecules in deionized water, and carrying out ultrasonic degassing for 20-30 minutes to obtain a solution A; 2, dissolving a water-soluble initiator, a cross-linking agent and a functional ion monomer in the solution A in nitrogen to obtain a solution B; 3, adding a thermal response material and a dual-response functional solution into the solution B, uniformly mixing, transferring to a constant-temperature environment of 60-65 DEG C, and reacting for 3-6 hours to obtain gel C; 4, washing the gel C with deionized water, soaking the gel C in a hydrochloric acid solution containing an oxidizing agent, taking out the gel, soaking the gel in a hydrochloric acid solution containing a conductive polymer monomer, reacting at 0-4 DEG C for 5-8 hours, and taking out the gel to obtain gel D; and 5, washing the gel D with deionized water, soaking the gel D in the deionized water, performing swelling equilibrium for 12-24 hours, and taking out the gel D to obtain the photo-thermal response type polyelectrolyte / conductive polymer interpenetrating network hydrogel which has stable multi-mode response capability and low crosstalk characteristics.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of flexible electronic materials, and particularly relates to a preparation method of a photo-thermal response type polyelectrolyte / conductive polymer interpenetrating network hydrogel. BACKGROUND

[0002] Traditional rigid electronic devices have significant limitations in dynamic complex environments such as wearable devices, soft robots and biological integrated systems, mainly manifested as insufficient mechanical compliance, poor interface adaptability and lack of environmental interaction capability. In contrast, conductive hydrogel realizes the mechanical properties and electrical properties of a biological tissue through the molecular-level cooperation of a three-dimensional hydrophilic network and a conductive medium, thereby providing an ideal platform for constructing a multi-stimulus response intelligent system.

[0003] As a core branch of stimulus response type intelligent materials, the research basis of conductive hydrogel is derived from the urgent demand of flexible electronic technology for a bionic adaptive system. The construction of the photo-thermal response type polyelectrolyte / conductive polymer interpenetrating network hydrogel is mainly based on three mechanisms: (1) photo response depends on the photoisomerization of functionalized photosensitive groups or the local thermal effect of photo-thermal materials; (2) thermal response adjusts the network osmotic pressure through the LCST phase transition of temperature-sensitive polymers; and (3) electric response relies on the electric field driven ion redistribution of the ion / electron conductive network. However, the construction of the existing photo-thermal response type polyelectrolyte / conductive polymer interpenetrating network hydrogel still has the following key bottlenecks: ① The conductive network is prone to phase separation under cyclic stimulation, and has poor long-term stability; ② There is a multi-function cross-talk problem, such as the swelling effect caused by thermal stimulation, which will irreversibly destroy the spatial configuration of the photo response group; and ③ The use of noble metal nanomaterials (such as Au / Ag nanowires) and multi-step synthesis process leads to high manufacturing cost, thereby limiting the scale production.

[0004] In summary, although the photo-thermal response type polyelectrolyte / conductive polymer interpenetrating network hydrogel has made progress in the single stimulus response field, it lacks systematic integration of the multi-stimulus cooperative regulation mechanism, especially the problems of energy conversion efficiency reduction and response signal distortion caused by competitive consumption of stimulus sources. Therefore, it is urgent to develop a conductive hydrogel system with stable multi-modal response ability, low cross-talk characteristic and scalable production, so as to meet the stringent requirements of the new generation of intelligent electronic devices for complex environment adaptability. SUMMARY

[0005] The application aims to provide a preparation method of a photo-thermal response type polyelectrolyte / conductive polymer interpenetrating network hydrogel, and the prepared hydrogel has stable multi-modal response ability and low cross-talk characteristic, and is low in cost and suitable for scale production.

[0006] The application is implemented by the following technical scheme: A preparation method of a photo-thermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel, comprising the following steps: Step 1, according to weight parts, respectively take 2-9 parts of rigid polymer, 2-9 parts of flexible polymer, 0.1-1.2 parts of water-soluble initiator, 0.1-0.8 parts of crosslinking agent, 0.5-1 parts of functional ionic monomer, 1-1.8 parts of thermal response material, 2-3 parts of double response functional solution, 0.1-1.2 parts of oxidizing agent, 1-2.5 parts of conductive polymer monomer and 30-40 parts of deionized water, wherein: the double response functional solution is prepared by mixing molybdenum-doped tungsten oxide quantum dots, poly(3,4-ethylenedioxythiophene-polybenzimidazole) and surfactant according to the mass ratio of 1:18:1; Step 2, the rigid polymer and the flexible polymer are dissolved in deionized water, stirred at 50-80℃ until completely dissolved, cooled to room temperature, ultrasonic degassing for 20-30 min, to obtain solution A; Step 3, under the condition of nitrogen protection, the water-soluble initiator, the crosslinking agent and the functional ionic monomer are sequentially added to the solution A, and stirred at room temperature until completely dissolved and uniformly mixed to obtain a uniform transparent solution B; Step 4, the thermal response material and the double response functional solution are added to the solution B, and after mixing uniformly, it is transferred to a constant temperature environment of 60-65℃, and sealed for reaction for 3-6 h to form a gel C with network structure; Step 5, the oxidizing agent and the conductive polymer monomer are respectively added to the hydrochloric acid solution with a concentration of 0.1-1 mol / L to obtain the hydrochloric acid solution containing the oxidizing agent and the hydrochloric acid solution containing the conductive polymer monomer, which are ready for use; Step 6, the surface of the gel C is first washed with deionized water, then soaked in the hydrochloric acid solution containing the oxidizing agent until the oxidizing agent diffuses into the gel, then the gel is taken out and immersed in the hydrochloric acid solution containing the conductive polymer monomer, and reacted at 0-4℃ for 5-8 h, then taken out to obtain a gel D; Step 7, the surface of the gel D is first washed with deionized water, then the gel D is soaked in deionized water to remove residual reagents, and swelled for 12-24 h, then taken out to obtain a photo-thermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel.

[0007] Further, the rigid polymer material of step 1 is polyvinyl alcohol grafted glycidyl methacrylate, polyurethane acrylate or polyamic acid acrylate.

[0008] Further, the flexible polymer of step 1 is polyethylene glycol diacrylate or polyethylene glycol naphthalate.

[0009] Further, the water-soluble initiator of step 1 is ammonium persulfate, ferric chloride, tetrachloroauric acid or potassium persulfate.

[0010] Further, the crosslinking agent in step 1 is N,N'-methylenebisacrylamide, N,N'-(1,2-dihydroxyethylene)bisacrylamide, or polyethylene glycol diacrylate.

[0011] Further, the functional ionic monomer in step 1 is methacryloyloxyethyltrimethylammonium chloride, dimethyldiallylammonium chloride, 2-acrylamido-2-methylpropanesulfonic acid, or sodium styrene sulfonate.

[0012] Further, the thermal response material in step 1 is poly(N-isopropylacrylamide), poly(ethylene oxide-propylene oxide) block copolymer, poly(N-vinylcaprolactam), or hydroxypropyl cellulose.

[0013] Furthermore, the surfactant in step 1 is Tween 80, sodium dodecyl sulfate, or hexadecyltrimethylammonium bromide.

[0014] Furthermore, the oxidant in step 1 is cerium ammonium sulfate, potassium iodate, ferric chloride, or potassium bromate.

[0015] Furthermore, the conductive polymer monomer in step 4 is 1,2,4-triaminobenzene, 3,4-ethylenedioxythiophene, or N-methylpyrrole.

[0016] The present invention has the following beneficial technical effects: First, the dual-network structure formed by rigid and flexible polymer materials effectively overcomes the brittleness or low strength defects of traditional hydrogels, enabling the hydrogel material to maintain structural integrity and mechanical stability during multiple stimulus-response cycles. Second, the introduction of functional ionic monomers facilitates the energy dissipation of dynamic ionic bond breaking, promotes salt ion diffusion, and improves conductivity. Third, the combination of low-dosage chemical crosslinking agents endows the material with dynamically reversible crosslinking points, which not only enhances energy dissipation but also provides modulus self-adaptation under stimulus response, exhibiting low multifunctional crosstalk characteristics. Fourth, the introduction of thermally responsive materials and dual-response functional solutions enables the hydrogel material to... The absorbed light energy is efficiently converted into heat energy, triggering phase transitions or conformational changes in the thermally responsive material; fifthly, the conductive polymer monomers are polymerized in situ under the action of an initiator to form a continuous conductive network, endowing the material with excellent electrical stimulation responsiveness; in summary, this invention introduces multiple stimulation-responsive materials into the hydrogel without the need to introduce precious metals, allowing them to work in conjunction with the hydrogel framework. The prepared hydrogel innovatively integrates multiple independent response mechanisms, achieving a sensitive and synergistic response capability of a single material to multiple environmental stimuli. This solves the key problems of limited conductivity, multifunctional crosstalk, and insufficient mechanical strength in traditional conductive hydrogels, expanding the application scenarios of hydrogel materials. Attached Figure Description

[0017] Figure 1 This is a reaction mechanism diagram of Embodiment 1 of the invention. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for explanation purposes only and are not intended to limit the scope of the invention.

[0019] The molybdenum-doped tungsten oxide quantum dots selected in Examples 1 to 6 of this invention were prepared by the following method: At room temperature, Na2WO4·2H2O and Na2MoO4·2H2O were taken at a mass ratio of 50:1, and then added to deionized water to prepare aqueous solutions of Na2WO4·2H2O and Na2MoO4·2H2O. The aqueous solutions of Na2WO4·2H2O and Na2MoO4·2H2O were then mixed. While stirring vigorously, dilute hydrochloric acid was added dropwise to adjust the pH value to strongly acidic, resulting in a light blue turbidity. The mixture was stirred continuously for 4 to 6 hours, and the precipitate was separated by centrifugation, washed with deionized water, and dried to obtain molybdenum-doped tungsten oxide quantum dots.

[0020] The polyvinyl alcohol-grafted glycidyl methacrylate used in Examples 1 and 4 of this invention was synthesized according to the method described in Junmei Zhang et al., "Facile fabrication of tough photocrosslinked polyvinyl alcoholhydrogels with cellulose nanofibrils reinforcement".

[0021] Example 1 Step 1: According to the weight proportions, take 9 parts of polyvinyl alcohol grafted glycidyl methacrylate, 9 parts of polyethylene glycol diacrylate, 1.2 parts of ammonium persulfate, 0.8 parts of N,N'-methylenebisacrylamide, 1 part of methacryloyloxyethyltrimethylammonium chloride, 1.8 parts of poly(N-isopropylacrylamide), 3 parts of dual-response functional solution, 1.2 parts of cerium ammonium sulfate, 2.5 parts of N-methylpyrrole, and 40 parts of deionized water, wherein: the dual-response functional solution is prepared by mixing molybdenum-doped tungsten oxide quantum dots, poly(3,4-ethylenedioxythiophene-polybenzimidazole), and Tween 80 in a mass ratio of 1:18:1; Step 2: Dissolve polyvinyl alcohol grafted with glycidyl methacrylate and polyethylene glycol diacrylate in deionized water, stir at 60°C until completely dissolved, cool to room temperature, and sonicate to degas for 30 min to obtain solution A; Step 3: Under nitrogen protection, add ammonium persulfate, N,N'-methylenebisacrylamide and methacryloyloxyethyltrimethylammonium chloride to solution A in sequence. Stir vigorously at room temperature until completely dissolved and mixed evenly to obtain a homogeneous and transparent solution B. Step 4: Add poly(N-isopropylacrylamide) and dual-response functional solution to solution B, mix well, transfer to a constant temperature environment of 60°C, seal and react for 6 h to allow the cross-linking copolymerization reaction to fully occur, forming gel C with a preliminary network structure. Step 5: Add ceric ammonium sulfate and N-methylpyrrole to a 0.1 mol / L hydrochloric acid solution to obtain a hydrochloric acid solution containing ceric ammonium sulfate and a hydrochloric acid solution containing N-methylpyrrole, respectively, for later use; Step 6: First, rinse the surface of gel C with deionized water, then immerse it in a hydrochloric acid solution containing cerium ammonium sulfate until the cerium ammonium sulfate diffuses into the gel. Then, take out the gel and immerse it in a hydrochloric acid solution containing N-methylpyrrole. React at 0°C for 8 hours, then take it out to obtain gel D. Step 7: First, rinse the surface of gel D with deionized water, then immerse gel D in deionized water to remove residual reagents. Allow it to swell and reach equilibrium for 24 h, then remove it to obtain a photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel.

[0022] Figure 1 The reaction mechanism diagram of Example 1 shows that: a rigid-flexible matrix network is formed by grafting glycidyl methacrylate and polyethylene glycol diacrylate onto polyvinyl alcohol under the initiation of ammonium persulfate, providing mechanical support; then, methacryloyloxyethyltrimethylammonium chloride participates in polymerization as a polyelectrolyte monomer, introducing ionic conductivity, while poly(N-isopropylacrylamide) acts as a thermal response unit, endowing the system with temperature control capability. On this basis, molybdenum-doped tungsten oxide quantum dots in the dual-response functional solution realize photothermal conversion, and local heating triggers the PNIPAM phase transition, realizing photo-thermal signal transmission; finally, cerium ammonium sulfate oxidation initiates the in-situ polymerization of N-methylpyrrole inside the gel, forming a conductive network that interpenetrates with the original network, achieving stable intelligent response behavior.

[0023] Example 2 Step 1: According to the weight parts, take 5.5 parts of polyurethane acrylate, 5.5 parts of polyethylene naphthalate, 0.4 parts of ammonium persulfate, 0.53 parts of N,N'-(1,2-dihydroxyethylene)bisacrylamide, 0.75 parts of dimethyl diallyl ammonium chloride, 1.3 parts of poly(ethylene oxide-propylene oxide) block copolymer, 2.6 parts of dual-response functional solution, 0.3 parts of potassium iodate, 1.75 parts of 3,4-ethylenedioxythiophene, and 35 parts of deionized water, wherein: the dual-response functional solution is prepared by mixing molybdenum-doped tungsten oxide quantum dots, poly(3,4-ethylenedioxythiophene-polybenzimidazole), and sodium dodecyl sulfate in a mass ratio of 1:18:1; Step 2: Dissolve polyurethane acrylate and polyethylene naphthalate in deionized water according to the weight parts, stir at 80°C until completely dissolved, cool to room temperature, and degas by sonication for 25 min to obtain solution A; Step 3: Under nitrogen protection, add ammonium persulfate, N,N'-(1,2-dihydroxyethylene)bisacrylamide and dimethyldiallylammonium chloride to solution A in sequence. Stir vigorously at room temperature until completely dissolved and mixed evenly to obtain a homogeneous and transparent solution B. Step 4: Add poly(ethylene oxide-propylene oxide) block copolymer and dual-response functional solution to solution B, mix well, transfer to a constant temperature environment of 63°C, seal and react for 4.5 h to fully undergo cross-linking copolymerization reaction and form gel C with preliminary network structure; Step 5: Add potassium iodate and 3,4-ethylenedioxythiophene to a 0.55 mol / L hydrochloric acid solution to obtain a hydrochloric acid solution containing potassium iodate and a hydrochloric acid solution containing 3,4-ethylenedioxythiophene, for later use. Step 6: First, rinse the surface of gel C with deionized water, then immerse gel C in hydrochloric acid solution containing potassium iodate until potassium iodate diffuses into the gel. Then, take out the gel and immerse it in hydrochloric acid solution containing 3,4-ethylenedioxythiophene. React at 4°C for 6.5 h, then take it out to obtain gel D. Step 7: First, rinse the surface of gel D with deionized water, then immerse gel D in deionized water to remove residual reagents, allow it to swell and equilibrate for 18 h, and then remove it to obtain a photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel.

[0024] Example 3 Step 1: According to the weight parts, take 2 parts of polyamic acid propylene ester, 2.1 parts of polyethylene glycol diacrylate, 0.1 parts of tetrachloroauric acid, 0.5 parts of 2-acrylamido-2-methylpropanesulfonic acid, 1 part of poly(N-vinylcaprolactam), 2 parts of dual-response functional solution, 0.1 parts of ferric chloride, 1 part of N-methylpyrrole, and 30 parts of deionized water, wherein: the dual-response functional solution is composed of molybdenum-doped tungsten oxide quantum dots, poly(3,4-ethylenedioxythiophene-polybenzimidazole), and hexadecyltrimethylammonium bromide in a mass ratio of 1:18:1; Step 2: Dissolve polyamic acid propylene ester and 2 parts of polyethylene glycol diacrylate taken in step 1 in deionized water, stir at 50°C until completely dissolved, cool to room temperature, and degas by sonication for 20 min to obtain solution A; Step 3: Under nitrogen protection, add tetrachloroauric acid, 0.1 part of polyethylene glycol diacrylate taken in step 1, and 2-acrylamido-2-methylpropanesulfonic acid to solution A in sequence. Stir vigorously at room temperature until completely dissolved and mixed evenly to obtain a homogeneous and transparent solution B. Step 4: Add poly(N-vinylcaprolactam) and the dual-response functional solution to solution B, mix well, transfer to a constant temperature environment of 64°C, seal and react for 3 h to allow the cross-linking copolymerization reaction to fully occur, forming gel C with a preliminary network structure. Step 5: Add ferric chloride and N-methylpyrrole to a 0.3 mol / L hydrochloric acid solution to obtain a hydrochloric acid solution containing ferric chloride and a hydrochloric acid solution containing N-methylpyrrole, respectively, for later use; Step 6: First, rinse the surface of gel C with deionized water, then immerse it in a hydrochloric acid solution containing ferric chloride until the ferric chloride diffuses into the gel. Then, take out the gel and immerse it in a hydrochloric acid solution containing N-methylpyrrole. React at 1°C for 7 h, and then take out gel D. Step 7: First, rinse the surface of gel D with deionized water, then immerse gel D in deionized water to remove residual reagents, allow it to swell and equilibrate for 12 h, and then remove it to obtain a photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel.

[0025] Example 4 Step 1: According to the weight parts, take 7 parts of polyvinyl alcohol grafted glycidyl methacrylate, 7 parts of polyethylene glycol diacrylate, 0.3 parts of potassium persulfate, 0.65 parts of N,N'-methylenebisacrylamide, 0.7 parts of sodium styrene sulfonate, 1.4 parts of hydroxypropyl cellulose, 2.8 parts of dual-response functional solution, 0.85 parts of potassium bromate, 2.2 parts of 1,2,4-triaminobenzene, and 36 parts of deionized water, wherein: the dual-response functional solution is prepared by mixing molybdenum-doped tungsten oxide quantum dots, poly(3,4-ethylenedioxythiophene-polybenzimidazole), and Tween 80 in a mass ratio of 1:18:1; Step 2: Dissolve polyvinyl alcohol grafted glycidyl methacrylate and polyethylene glycol diacrylate in deionized water, stir at 70°C until completely dissolved, cool to room temperature, and sonicate to degas for 27 min to obtain solution A; Step 3: Under nitrogen protection, potassium persulfate, N,N'-methylenebisacrylamide and sodium styrene sulfonate are added to solution A in sequence. The mixture is stirred vigorously at room temperature until it is completely dissolved and mixed evenly to obtain a homogeneous and transparent solution B. Step 4: Add hydroxypropyl cellulose and dual-response functional solution to solution B, mix well, transfer to a constant temperature environment of 62°C, seal and react for 4 h to allow the cross-linking copolymerization reaction to fully occur, forming gel C with a preliminary network structure. Step 5: Add potassium bromate and 1,2,4-triaminobenzene to a 0.7 mol / L hydrochloric acid solution to obtain a hydrochloric acid solution containing potassium bromate and a hydrochloric acid solution containing 1,2,4-triaminobenzene, for later use. Step 6: First, rinse the surface of gel C with deionized water, then immerse gel C in a hydrochloric acid solution containing potassium bromate until the potassium bromate diffuses into the gel. Then, take out the gel and immerse it in a hydrochloric acid solution containing 1,2,4-triaminobenzene. React at 2°C for 6 hours, then take it out to obtain gel D. Step 7: First, rinse the surface of gel D with deionized water, then immerse gel D in deionized water to remove residual reagents. Allow it to swell and reach equilibrium for 20 h, then remove it to obtain a photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel.

[0026] Example 5 Step 1: According to the weight parts, take 4 parts of polyamic acid propylene ester, 4 parts of polyethylene naphthalate, 0.7 parts of potassium persulfate, 0.45 parts of N,N'-(1,2-dihydroxyethylene)bisacrylamide, 0.52 parts of methacryloyloxyethyltrimethylammonium chloride, 1.2 parts of poly(N-isopropylacrylamide), 2.5 parts of dual-response functional solution, 0.65 parts of cerium ammonium sulfate, 1.5 parts of 1,2,4-triaminobenzene, and 33 parts of deionized water, wherein: the dual-response functional solution is prepared by mixing molybdenum-doped tungsten oxide quantum dots, poly(3,4-ethylenedioxythiophene-polybenzimidazole), and sodium dodecyl sulfate in a mass ratio of 1:18:1; Step 2: Dissolve polyamic acid propylene ester and polyethylene naphthalate in deionized water, stir at 65°C until completely dissolved, cool to room temperature, and sonicate to degas for 25 min to obtain solution A; Step 3: Under nitrogen protection, potassium persulfate, N,N'-(1,2-dihydroxyethylene)bisacrylamide and methacryloyloxyethyltrimethylammonium chloride are added to solution A in sequence. The mixture is stirred vigorously at room temperature until it is completely dissolved and mixed evenly to obtain a homogeneous and transparent solution B. Step 4: Add poly(N-isopropylacrylamide) and dual-response functional solution to solution B, mix well, transfer to a constant temperature environment of 61°C, seal and react for 5 h to allow the cross-linking copolymerization reaction to fully occur, forming gel C with a preliminary network structure. Step 5: Add cerium ammonium sulfate and 1,2,4-triaminobenzene to a 0.8 mol / L hydrochloric acid solution to obtain a hydrochloric acid solution containing cerium ammonium sulfate and a hydrochloric acid solution containing 1,2,4-triaminobenzene, respectively, for later use; Step 6: First, rinse the surface of gel C with deionized water, then immerse it in a hydrochloric acid solution containing cerium ammonium sulfate until the cerium ammonium sulfate diffuses into the gel. Then, take out the gel and immerse it in a hydrochloric acid solution containing 1,2,4-triaminobenzene. React at 3°C ​​for 5 h, then take it out to obtain gel D. Step 7: First, rinse the surface of gel D with deionized water, then immerse gel D in deionized water to remove residual reagents, allow it to swell and equilibrate for 17 h, and then remove it to obtain a photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel.

[0027] Example 6 Step 1: According to the weight parts, take 8 parts of polyurethane acrylate, 8 parts of polyethylene naphthalate, 1 part of ferric chloride, 0.72 parts of polyethylene glycol diacrylate, 0.8 parts of dimethyl diallyl ammonium chloride, 1.6 parts of poly(N-isopropylacrylamide), 2.91 parts of dual-response functional solution, 1 part of potassium bromate, 2.35 parts of N-methylpyrrole, and 38 parts of deionized water, wherein: the dual-response functional solution is composed of molybdenum-doped tungsten oxide quantum dots, poly(3,4-ethylenedioxythiophene-polybenzimidazole), and hexadecyltrimethylammonium bromide in a mass ratio of 1:18:1; Step 2: Dissolve polyurethane acrylate polyethylene naphthalate in deionized water according to the weight parts, stir at 75°C until completely dissolved, cool to room temperature, and degas by sonication for 26 min to obtain solution A; Step 3: Under nitrogen protection, ferric chloride, polyethylene glycol diacrylate and dimethyl diallyl ammonium chloride are added to solution A in sequence. At room temperature, the mixture is stirred vigorously until it is completely dissolved and mixed evenly to obtain a homogeneous and transparent solution B. Step 4: Add poly(N-isopropylacrylamide) and dual-response functional solution to solution B, mix well, transfer to a constant temperature environment of 65°C, seal and react for 3 h to allow the cross-linking copolymerization reaction to fully occur, forming gel C with a preliminary network structure. Step 5: Add potassium bromate and N-methylpyrrole to a 1 mol / L hydrochloric acid solution to obtain a hydrochloric acid solution containing potassium bromate and a hydrochloric acid solution containing N-methylpyrrole, for later use; Step 6: First, rinse the surface of gel C with deionized water, then immerse it in a hydrochloric acid solution containing potassium bromate until the potassium bromate diffuses into the gel. Then, take out the gel and immerse it in a hydrochloric acid solution containing N-methylpyrrole. React at 2.5℃ for 7 h to obtain gel D. Step 7: First, rinse the surface of gel D with deionized water, then immerse gel D in deionized water to remove residual reagents. Allow it to swell and reach equilibrium for 22 h, then remove it to obtain a photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel.

[0028] The conductivity of the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogels prepared in Examples 1-6 was tested using an electrochemical workstation. The test method is as follows: The photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogels prepared in Examples 1-6 were cut into samples of the required size and fixed, clamped at both ends of the electrode clamp, and the voltage was set to 1.5 V. The conductivity of the hydrogel sample was measured. σ The calculation formula is as follows: σ = d / (R×A) In the formula: d represents the distance between adjacent electrodes, in mm; R represents the resistance of the hydrogel sample, in Ω; A represents the cross-sectional area of ​​the hydrogel sample, in mm². 2 .

[0029] During the testing process, light stimulation and thermal stimulation were applied separately, and the conductivity under different stimulation states was recorded. Table 1 shows the conductivity test results of the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogels prepared in Examples 1-6 without any external stimulation; Table 2 shows the conductivity test results of the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogels prepared in Examples 1-6 under light stimulation; Table 3 shows the conductivity test results of the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogels prepared in Examples 1-6 under thermal stimulation. Table 1. Conductivity of hydrogels prepared in Examples 1-6 without stimulation. As can be seen from Table 1, the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogels prepared in Examples 1-6 all have good conductivity and can stably transmit signals when applied to electro-responsive applications.

[0030] Table 2. Conductivity changes of hydrogels prepared in Examples 1-6 under light stimulation As can be seen from Table 2, the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogels prepared in Examples 1-6 all exhibit good conductivity under light stimulation and can stably transmit signals when applied to photoresponsive applications.

[0031] Table 3. Conductivity changes of hydrogels prepared in Examples 1-6 under thermal stimulation. As can be seen from Table 3, the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogels prepared in Examples 1-6 all exhibit good conductivity under thermal stimulation and can stably transmit signals when applied to photoresponsive applications.

[0032] In summary, the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel systems prepared in Examples 1 to 6 achieve multi-stimulus response through the synergistic effect of multiple components. Specifically, the photothermal material absorbs thermal energy, triggering the thermally responsive polymer network to generate photothermal drive; the conductive polymer monomers are polymerized in situ with a water-soluble initiator to form a conductive network, which undergoes a reversible redox reaction when an electric field is applied, inducing polymer chain changes and osmotic pressure changes, synergistically generating electrochemical drive; the interpenetrating structure constructed from rigid and flexible networks provides mechanical support and energy dissipation, and combined with dynamic ionic crosslinking and low-dose chemical crosslinking, improves the structural stability and toughness of the material under cyclic stimulation. This synergistic mechanism of photothermal-electrochemical-ion migration enables the hydrogel to respond efficiently to ambient light / heat / electric signals and achieve energy-saving operation by relying on the "daytime photothermal drive and nighttime electrical control supplement" mode.

Claims

1. A method for preparing a photothermally responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel, characterized in that, Includes the following steps: Step 1: According to the weight parts, take 2-9 parts of rigid polymer, 2-9 parts of flexible polymer, 0.1-1.2 parts of water-soluble initiator, 0.1-0.8 parts of crosslinking agent, 0.5-1 parts of functional ionic monomer, 1-1.8 parts of thermally responsive material, 2-3 parts of dual-response functional solution, 0.1-1.2 parts of oxidant, 1-2.5 parts of conductive polymer monomer and 30-40 parts of deionized water, wherein: the dual-response functional solution is composed of molybdenum-doped tungsten oxide quantum dots, poly(3,4-ethylenedioxythiophene-polybenzimidazole) and surfactant in a mass ratio of 1:18:1; Step 2: Dissolve the rigid polymer and the flexible polymer in deionized water, stir at 50-80℃ until completely dissolved, cool to room temperature, and degas by sonication for 20-30 min to obtain solution A; Step 3: Under nitrogen protection, add water-soluble initiator, crosslinking agent and functional ionic monomer to solution A in sequence. Stir vigorously at room temperature until completely dissolved and mixed evenly to obtain a homogeneous and transparent solution B. Step 4: Add the thermally responsive material and the dual-response functional solution to solution B, mix them evenly, transfer them to a constant temperature environment of 60-65℃, seal and react for 3-6 hours to form gel C with a network structure; Step 5: Add the oxidant and the conductive polymer monomer to a hydrochloric acid solution with a concentration of 0.1-1 mol / L, respectively, to obtain a hydrochloric acid solution containing the oxidant and a hydrochloric acid solution containing the conductive polymer monomer, for later use; Step 6: First, rinse the surface of gel C with deionized water, then immerse it in a hydrochloric acid solution containing an oxidant until the oxidant diffuses into the gel. Then, take out the gel and immerse it in a hydrochloric acid solution containing conductive polymer monomers. React at 0-4℃ for 5-8 hours, then take it out to obtain gel D. Step 7: First, rinse the surface of gel D with deionized water, then immerse gel D in deionized water to remove residual reagents. Allow it to swell and equilibrate for 12-24 hours, then remove it to obtain a photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel.

2. The method for preparing the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel according to claim 1, characterized in that, The rigid polymer material in step 1 is polyvinyl alcohol grafted with glycidyl methacrylate, polyurethane acrylate, or polyamic acid propylene ester.

3. The method for preparing the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel according to claim 1, characterized in that, The flexible polymer in step 1 is polyethylene glycol diacrylate or polyethylene naphthalate.

4. The method for preparing the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel according to claim 1, characterized in that, The water-soluble initiator in step 1 is ammonium persulfate, ferric chloride, tetrachloroauric acid, or potassium persulfate.

5. The method for preparing the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel according to claim 1, characterized in that, The crosslinking agent in step 1 is N,N'-methylenebisacrylamide, N,N'-(1,2-dihydroxyethylene)bisacrylamide, or polyethylene glycol diacrylate.

6. The method for preparing the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel according to claim 1, characterized in that, The functional ionic monomer in step 1 is methacryloyloxyethyltrimethylammonium chloride, dimethyldiallylammonium chloride, 2-acrylamido-2-methylpropanesulfonic acid, or sodium styrene sulfonate.

7. The method for preparing the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel according to claim 1, characterized in that, The thermal response material in step 1 is poly(N-isopropylacrylamide), poly(ethylene oxide-propylene oxide) block copolymer, poly(N-vinylcaprolactam), or hydroxypropyl cellulose.

8. The method for preparing the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel according to claim 1, characterized in that, The surfactant in step 1 is Tween 80, sodium dodecyl sulfate, or hexadecyltrimethylammonium bromide.

9. The method for preparing the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel according to claim 1, characterized in that, The oxidant in step 1 is cerium ammonium sulfate, potassium iodate, ferric chloride, or potassium bromate.

10. The method for preparing the photothermal responsive polyelectrolyte / conductive polymer interpenetrating network hydrogel according to claim 1, characterized in that, The conductive polymer monomer in step 4 is 1,2,4-triaminobenzene, 3,4-ethylenedioxythiophene, or N-methylpyrrole.

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