Bamboo shoot biological template-based high-strength anisotropic composite hydrogel as well as preparation method and bionic driving application thereof

Abstract

The invention discloses a high-strength anisotropic composite hydrogel based on a bamboo shoot biological template, which is characterized in that a natural bamboo shoot pore structure is compounded with poly (N-isopropylacrylamide), and then nigrosine is introduced to obtain a composite hydrogel intelligent driving material with a heterogeneous interpenetrating network structure. The material disclosed by the invention has relatively strong mechanical properties (the tensile strength is 2.0 MPa) and strong driving force (heavy objects more than 100 times of the material can be lifted), and has relatively high deformation speed (the bending speed reaches 37.6 degrees / s) when being subjected to external stimulation, so that the material has an application prospect in the field of photo-thermal driving-self-sensing dual-function synergistic bionic device materials.

Description

Technical Field

[0001] The present invention relates to the field of functional polymer materials, and in particular to a high-strength anisotropic composite hydrogel based on a bamboo shoot biological template, a preparation method thereof, and a biomimetic driving application thereof. Background Art

[0002] Smart hydrogel is one of the new biomimetic materials that has developed rapidly in recent years and has attracted widespread attention in many fields such as soft actuation and flexible sensing. As a type of flexible actuator, smart actuated hydrogel has realized a variety of complex actuation functions, including creeping, rolling, walking, jumping and grasping, which have broad application prospects in many fields. The actuator has the advantages of volume controllability, fast response speed and strong reversibility. At the same time, because hydrogel materials have a unique soft / wet structure similar to organisms, good biocompatibility and excellent biodegradability, they have great potential application value in many emerging fields such as soft robots, drug controlled release, and smart valves. After decades of development, smart actuated hydrogels have achieved certain results: (1) The deformation (actuation) mode has evolved from the initial simple volume expansion / contraction to the ability to realize various complex actuation modes. (2) Designing a high specific surface area structure to increase its response deformation speed. (3) Designing a special hydrogel structure to improve its mechanical properties and thus obtain a larger actuation force.

[0003] Although the existing smart hydrogels have achieved certain improvements in their complex deformation degree, driving speed and mechanical properties, most of these improvements are based on bionic structures prepared from various purely artificial synthetic raw materials. The preparation methods are also relatively cumbersome and not universal, and they can often only improve one of the properties, which seriously limits their further application. For example, Chinese patent CN202210416680.X discloses a nanosponge / gelatin composite hydrogel actuator, which uses nanosponge as a "skeleton" and adds gelatin hydrogel as "muscle" to the nanosponge to obtain an anisotropic composite hydrogel with excellent mechanical properties and multiple solution response characteristics. However, most smart hydrogels have problems such as slow response rate, weak driving force, single driving mode, and difficulty in real-time detection and feedback of the driving process, which greatly limits their scope of application. Summary of the Invention

[0004] In view of this, the present invention provides a high-strength anisotropic composite hydrogel based on a bamboo shoot biological template to solve the problems of existing smart hydrogels such as slow response rate, weak driving force, and single driving mode.

[0005] The present invention adopts a preparation method of a high-strength anisotropic composite hydrogel based on a bamboo shoot biological template, comprising the following steps: pre-treating bamboo shoot slices with an ethanol solution; then immersing the bamboo shoot slices in a poly (N-isopropylacrylamide) hydrogel prepolymer solution and ultrasonicating the slices; then taking out the slices and placing them in a mold for ultraviolet light polymerization and washing to obtain a heterogeneous interpenetrating network structure hydrogel; finally, immersing the heterogeneous interpenetrating network structure hydrogel in a nigrosine solution, ultrasonicating the slices, and washing the slices to obtain an N-BSPH hydrogel;

[0006] The poly (N-isopropylacrylamide) hydrogel prepolymer solution includes 1500 mg of monomer N-isopropylacrylamide, 50 mg of N,N-methyleneacrylamide, 50 mg of azobisisobutylamidine hydrochloride and 15 mL of water.

[0007] Preferably, the photopolymerization time is 10 minutes.

[0008] Preferably, the mass concentration of the ethanol solution is 50%.

[0009] Preferably, the concentration of the nigrosine solution is 7 mg / mL.

[0010] On the other hand, the present invention also provides an application of a high-strength anisotropic composite hydrogel based on a bamboo shoot biological template in the preparation of a photothermal drive-self-sensing dual-function synergistic bionic device material.

[0011] Using the method provided by the present invention, ultraviolet light polymerization is first used to fully penetrate the poly (N-isopropylacrylamide) gel prepolymer solution into the bamboo shoots, allowing strong hydrogen bonds to form between the gel network and the cellulose network of the bamboo shoots. This results in a heterogeneous interpenetrating network composite hydrogel (BSPH) intelligent actuation material. The BSPH intelligent actuation material prepared by the method of the present invention exhibits strong mechanical properties (tensile strength of 2.0 MPa), strong driving force (capable of lifting objects weighing more than 100 times its own weight), and precisely programmable complex actuation (complex deformations such as three-dimensional spirals at different angles). Furthermore, the BSPH intelligent actuation material exhibits high structural stability, does not peel off during various complex actuation processes, and can fully recover its original shape.

[0012] Furthermore, the N-BSPH smart hydrogel prepared by the method of the present invention not only has controllable photothermal response and ultra-fast complex driving performance (bending speed 314° / s, bending speed 483° / s), but also has self-sensing performance, that is, it can detect the conductive signal in the deformation process in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of the preparation of a high-strength anisotropic composite hydrogel (BSPH) based on a bamboo shoot bio-template of the present invention;

[0014] Figure 2is the Fourier transform infrared spectrum (FT-IR) of BS and BSPH;

[0015] Figure 3 is the scanning electron microscopy (SEM) image of the cross section of BSPH;

[0016] Figure 4 Stress-strain curves of BS-Y, BSPH-Y and PNIPAM hydrogels;

[0017] Figure 5 Mechanical properties of BS and BSPH, where (a) and (b) are stress-strain curves in two directions, (c) and (d) are Young's modulus and elongation at break in two directions, respectively;

[0018] Figure 6 The hydrophilicity results of BS and BSPH;

[0019] Figure 7 (a) Response process of BSPH; (b) Recovery process of BSPH; (c) Bending angle of BSPH at different temperatures; (d) Reversible cycle test of BSPH (scale bar: 5 mm);

[0020] Figure 8 (a) Schematic diagram of complex deformation of BSPH cut at different angles; (b) Temperature variation of BSPH cut at different angles (scale: 5 mm);

[0021] Figure 9 XPS spectra of BSPH and N-BSPH;

[0022] Figure 10 EDS-mapping diagrams of the cross sections of (a) BSPH and (b) N-BSPH;

[0023] Figure 11 (a) Bending angle change curve under BSPH surface light source illumination; (b) Recovery process of BSPH surface light source; (c) Reversible cycle test of BSPH surface light source (scale bar: 5 mm);

[0024] Figure 12 (a) Bending angle change curve under BSPH point light source illumination; (b) Recovery process of BSPH point light source; (c) Reversible cycle process of BSPH point light source; (Scale bar: 5 mm);

[0025] Figure 13 Programmable complex actuation of N-BSPH smart hydrogel under near-infrared light irradiation (scale bar: 5 mm);

[0026] Figure 14 The process of lifting heavy objects for the "bionic hook". DETAILED DESCRIPTION

[0027] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0028] Example 1: Reference Figure 1 A high-strength anisotropic composite hydrogel (BSPH) based on a bamboo shoot bio-template was prepared by the following method:

[0029] S101: Fresh bamboo shoots were cut into thin slices (250 μm*1 cm*2.5 mm), and soaked in a 50% ethanol solution for 12 hours. The slices were then washed three times with deionized water to remove impurities such as hemicellulose, protein, and sugar.

[0030] S102: 1500 mg of monomer N-isopropylacrylamide (NIPAM), 50 mg of cross-linker N,N-methyleneacrylamide (BIS), and 50 mg of photoinitiator azobisisobutylamidine hydrochloride (AIBA) were weighed and added to 15 mL of deionized water and placed on a vortex rotator for 3 minutes to obtain a PNIPAM hydrogel prepolymer solution;

[0031] S103: The pretreated bamboo shoot slices were soaked in PNIPAM hydrogel prepolymer solution for 24 h, then ultrasonicated for 30 min, and then the soaked bamboo shoot slices were taken out and placed in a silicone rubber mold. The excess prepolymer solution around the mold was absorbed with a paper towel, and the mold was covered with a quartz glass sheet, sealed with a clip, and placed in a refrigerator for 10 min. Then, the slices were taken out and placed under ultraviolet light (365 nm, 12.8 W / cm 2 ) for 10 min, and then the BSPH hydrogel was immersed in a large amount of deionized water for 2 d to remove the unreacted monomers and other impurities in the hydrogel, and finally the BSPH hydrogel was obtained.

[0032] Example 2: Preparation of a high-strength anisotropic composite hydrogel (N-BSPH) based on bamboo shoot bio-template, comprising the following steps:

[0033] S101: Cut fresh bamboo shoots into thin slices (0.25 mm × 10 mm × 2.5 mm), soak them in 50% ethanol solution for 12 h, and then remove them and wash them three times with deionized water;

[0034] S102: 1500 mg of monomer N-isopropylacrylamide (NIPAM), 50 mg of cross-linker N,N-methyleneacrylamide (BIS), and 50 mg of photoinitiator azobisisobutylamidine hydrochloride (AIBA) were weighed and added to 15 mL of deionized water and placed on a vortex rotator for 3 minutes to obtain a PNIPAM hydrogel prepolymer solution;

[0035] S103: The pretreated bamboo shoot slices were soaked in PNIPAM hydrogel prepolymer solution for 24 h, then ultrasonicated for 30 min, and then the soaked bamboo shoot slices were taken out and placed in a silicone rubber mold. The excess prepolymer solution around the mold was absorbed with a paper towel, and the mold was covered with a quartz glass sheet, sealed with a clip, and placed in a refrigerator for 10 min. Then, the slices were taken out and placed under ultraviolet light (365 nm, 12.8 W / cm 2 ) for 10 min, and then the BSPH hydrogel was immersed in a large amount of deionized water for 2 d to remove unreacted monomers and other impurities in the hydrogel, and finally the BSPH hydrogel was obtained;

[0036] S104: Soak the BSPH hydrogel in 15 mL of a 7 mg / mL nigrosine aqueous solution for 12 hours, ultrasonically treating the solution for 30 minutes. The resulting N-BSPH hydrogel is then soaked in a large amount of deionized water for 12 hours to remove excess nigrosine, thereby obtaining the N-BSPH hydrogel.

[0037] Comparative Example 1: The difference between Comparative Example 1 and the embodiment is that the fresh bamboo shoot slices were not treated with the 50% ethanol solution in S101, but were directly placed in the PNIPAM hydrogel prepolymer solution for UV polymerization. The PNIPAM hydrogel prepolymer solution has difficulty penetrating into the interior of the bamboo shoots and only adheres to their surface.

[0038] Comparative Example 2: The difference between Comparative Example 2 and Example 2 is that in step S104, the same amount of graphene or MXene is selected as a photothermal material to be compounded with the BSPH hydrogel, and it is found that it cannot be successfully adsorbed by the BSPH hydrogel. The experimental results show that graphene or MXene as a photothermal material can only adhere to the surface of the hydrogel, and after multiple deionization soaking, the graphene or MXene black photothermal conversion material will fade. This shows that the hydroxyl groups in aniline black can form hydrogen bonds with the amino groups in the PNIPAM hydrogel, so aniline black can be well attached to BSPH. However, photothermal materials such as graphene or MXene cannot penetrate well into the interior of BSPH.

[0039] The BSPH hydrogel or N-BSPH hydrogel prepared in the above examples was characterized and tested:

[0040] (1) Figure 2 As shown in the infrared spectrum of BSPH, it is found that there is a stretching vibration peak (3293cm -1 ), the stretching vibration peak of the CH bond on the methyl group (2923cm -1 ), the stretching vibration peak of the -C=N- bond on the aromatic ring (1641cm -1 ), the in-plane vibration peak of the CH bond is (1238cm -1 and 1034cm-1 ), and the corresponding PNIPAM hydrogel stretching vibration peak in NH (3433cm -1 and 3294cm -1 ), C=O stretching vibration peak (1638cm -1 ), the deformation vibration peak of NH (1534cm -1 ), the stretching vibration peak of CN (1456cm -1 ), -NH2 in-plane vibration peak (1161cm -1 ). This also shows that PNIPAM has successfully penetrated into the natural bamboo shoot slices. In addition, at 1161~1029cm -1 Within this range, the absorption peak of the NH2 in-plane rocking vibration changed, and stronger hydrogen bonds were formed between the PNIPAM chains and CNFs.

[0041] (2) Figure 3 Scanning electron microscopy results show that after the infiltration of the PNIPAM hydrogel prepolymer, the pores in the bamboo shoot cross section are blocked, the pore walls thicken, and the PNIPAM and the grooves on the bamboo shoot pore walls form a mechanical interlocking structure, which prevents the gel from falling out of the pore walls. The oriented structure and cross-linked PNIPAM chains can be seen in the magnified nanoscale grooves, indicating the formation of a heterogeneous interpenetrating network structure. These phenomena indicate that the PNIPAM hydrogel prepolymer has completely penetrated the interior of the BS and confirm that the NSPH smart hydrogel will not peel or break during subsequent complex deformation processes.

[0042] (3) Figure 4 As shown in the stress-strain curve results, this study combines natural bamboo shoots with PNIPAM to prepare BSPH smart hydrogels with heterogeneous interpenetrating networks, which can greatly improve the mechanical properties of hydrogels. (Y represents the direction parallel to the fiber), it can be seen that the tensile strength of BS parallel to the fiber direction is 1.51MPa, and after compounding BS with PNIPAM, the tensile strength of BSPH with a heterogeneous interpenetrating network parallel to the fiber direction is 1.94MPa, which is much higher than the tensile strength of PNIPAM hydrogel of 0.019MPa. From the comparison of tensile properties, it can be seen that the tensile strength of BSPH smart hydrogel with heterogeneous interpenetrating network structure is 100 times higher than that of pure PNIPAM hydrogel, indicating that compounding with BS can significantly improve the mechanical properties of PNIPAM hydrogel. In addition, Figure 5 As shown, the Young's modulus in both directions of the BSPH smart hydrogel composited with BS and PNIPAM increased, reaching 1.86 MPa and 0.44 MPa, respectively, with a difference of 4.23 times, showing good anisotropy.

[0043] (4) BSPH hydrophilicity test

[0044] In this study, contact angle tests were conducted on BS and BSPH. Figure 6 As shown in the figure, the BSPH angle decreased from 71.8° to 42.8°. This is because the PNIPAM hydrogel successfully penetrated into the BS and formed hydrogen bonds with the surface hydroxyl groups. This shows that BSPH also has good hydrophilicity, which provides the possibility for subsequent photothermal response.

[0045] (5) Study on BSPH temperature response driving performance

[0046] like Figure 7 BSPH smart hydrogel actuator (10×3×0.25mm 3 ) When placed in 32°C warm water, the actuator immediately began to bend, and the BSPH smart hydrogel could reach 120° within 2s. Within 12s, the bending angle of the BSPH smart hydrogel actuator reached a maximum value of 451.2°, with a response speed of 37.6° / s. After the bending angle in 32°C warm water was stabilized, the BSPH smart hydrogel was placed in 25°C cold water to observe its recovery process. It was found that the BSPH hydrogel recovered very quickly, and it only took 14s to recover from the initial 460° to the initial 0°, with a recovery speed of 32.8° / s. This shows that the BSPH smart hydrogel has super-hydrophilic fiber-oriented pore channels, which accelerates water transfer.

[0047] In addition, the BSPH smart hydrogel actuator (10×3×0.25mm 3 )Bending angles at different water temperatures from 24°C to 40°C, such as Figure 7 c It can be seen that when the temperature is around 24°C, the BSPH smart hydrogel actuator maintains its initial state with almost no bending, but as the temperature rises, its bending angle gradually increases. This is because the water temperature gradually reaches the LCST of the PNIPAM hydrogel, and the actuator will lose water and shrink. When the temperature is around 40°C, the water inside the PNIPAM hydrogel in the actuator is basically exhausted, and its bending angle slowly increases. In order to verify the cyclic stability of its actuator, this study carried out 30 deformation / recovery processes (BSPH in 25°C cold water and 40°C hot water) Figure 7 d), indicating that the driver has no fatigue phenomenon and has excellent durability, laying the foundation for subsequent drive applications.

[0048] (5) Study on driving behavior of BSPH

[0049] The BSPH smart hydrogel was cut into strips of different angles (12×2.8×0.25mm 3 ),like Figure 8 As shown in a, the BSPH smart hydrogel finally deforms in 40℃ hot water. Figure 8b is a diagram of the complex deformation process from 20°C cold water to 40°C hot water. It was found that when the cutting is parallel to the fiber direction, the actuator eventually bends into a 360° cylinder. It was found that when the fiber direction is perpendicular to the cutting direction, the actuator eventually bends into a 360° ring. The BSPH smart hydrogel actuator was cut at other angles (30°, 45°, and 60°). It was found that the initial bend turned into a spiral, and as the cutting angle increases, the pitch becomes shorter, indicating that the deformation of the actuator is controllable and can achieve complex driving behavior. When subjected to external stimuli, the BSPH smart hydrogel has rapid material exchange and energy transmission, resulting in faster deformation and recovery speeds.

[0050] (6) Figure 9 As shown, based on X-ray photoelectron spectroscopy (XPS), the differences in the content of sodium and sulfur elements in BSPH and N-BSPH were analyzed. It was found that N-BSPH with the addition of aniline black showed characteristic peaks of S2p and Na1s at binding energies of 1071eV and 168eV, respectively, while BSPH did not have these two characteristic peaks, which indirectly confirmed that aniline black was successfully combined with BSPH to form N-BSPH smart hydrogel that can be remotely photothermally driven.

[0051] (7) Figure 10 The EDS mapping diagram shown in the figure shows that there are a large number of S and Na elements in the cross section of N-BSPH, which proves that aniline black has penetrated into BSPH very well and is evenly distributed. At the same time, the addition of aniline black does not damage its structure and retains the original pore structure.

[0052] (8) Photothermal drive performance test of N-BSPH

[0053] A long strip of N-BSPH smart hydrogel with a size of 9 mm in length, 3 mm in width and 0.25 mm in thickness was selected as the sample. 2 Under near-infrared light, N-BSPH quickly bends from 0° to 369° in just 0.79s (the average bending speed is 314° / s) ( Figure 11 a). After the surface light source is removed, it gradually returns to its initial state after 21 seconds ( Figure 11 b). The study found that compared with the photothermal drive of PNIPAM smart hydrogel, N-BSPH smart hydrogel showed faster response and recovery speed. In addition, the high reversibility of the hydrogel was verified based on 30 cycles of cycling experiments ( Figure 11 c).

[0054] (9) The bending properties of N-BSPH were quantitatively studied, and a long strip of N-BSPH smart hydrogel with a length of 12 mm, a width of 1 mm, and a thickness of 0.25 mm was selected as the experimental sample. Then, an intensity of 38.2 W / cm 2 Under the irradiation of near-infrared light source, the long composite hydrogel only needs 0.297s to bend from 0° to 87° (the average bending speed is as high as 483° / s) ( Figure 12 a). Immediately after turning off the point light source, the long strip of N-BSPH smart hydrogel can recover from 87° to its initial state within 6.33s ( Figure 12 b), and also has a faster recovery speed. This is because BS has a cellulose structure with rich directional pores, which can accelerate material exchange and energy transfer when stimulated by external near-infrared light. In addition, the bending process of N-BSPH smart hydrogel is also reversible. After the entire bending-recovery process is repeated 20 times, there is almost no effect on the performance of N-BSPH. Figure 12 c) This experiment also confirmed that N-BSPH smart hydrogel has good fatigue resistance and structural stability.

[0055] (10) In addition, under near-infrared light irradiation (808 nm, 8.5 W / cm 2 ), due to N-BSPH (12 × 3.8 × 0.25mm 3 ) contains aniline black with high photothermal conversion efficiency and different cutting angles with the fiber direction. The smart hydrogel can be curled into spirals of different lengths ( Figure 13 a) As the cutting angle increases, the helical length of the N-BSPH hydrogel actuator decreases. The helical length of N-BSPH at 60° is shorter than that at 30°. In particular, at 0°, N-BSPH coils into a long tube, while at 90°, it curls into a ring. Furthermore, during the complex deformation process, N-BSPH maintains a certain distance from the near-infrared light, demonstrating its excellent remote controllability. The N-BSPH intelligently actuated hydrogel can precisely perform a variety of complex photothermal-responsive deformations.

[0056] (11) Bionic drive applications of N-BSPH

[0057] The present invention uses the N-BSPH hydrogel of Example 2 to design a "bionic hook" that can "lift" and "put down" heavy objects under the irradiation of a near-infrared light source ( Figure 14 First, the “bionic hook” was designed into a strip with a length of 15 mm, a thickness of 3 mm and a thickness of 0.25 mm as an experimental sample (10.5 mg). Then, a near-infrared light source (808 nm, 11.5 W / cm 2), under its full irradiation, the "bionic hook" began to bend and hook the "heavy object" (1068.3 mg), and was completely "lifted" at 4.6 seconds. After the light source was turned off, it continued to move upward with the help of external force, and maintained the state of grabbing the heavy object. The N-BSPH smart hydrogel can return to its original shape and "put down" the heavy object in just 12.5 seconds. It can be seen that the N-BSPH smart hydrogel not only has an excellent driving speed (bends and "lifts heavy objects" in 4.6 seconds), but also has a strong driving force ("lifts" a "heavy object" that is more than 100 times its own weight). This shows that the N-BSPH smart hydrogel of the present invention has a fast response speed and recovery speed under the irradiation of near-infrared light. Moreover, under near-infrared irradiation, the driving behavior of the N-BSPH smart hydrogel can be precisely controlled, and it has great application prospects in the field of intelligent soft machines.

[0058] In summary, on the one hand, the present invention utilizes the BS-PNIPAM heterogeneous interpenetrating network composite hydrogel (BSPH) intelligent driving material prepared by the method provided by the present invention. It not only has excellent mechanical properties (tensile strength of 2.0MPa) / corresponding strong driving force (lifting more than 100 times its own weight) and precisely programmable complex driving (complex deformations such as three-dimensional spirals at different angles); and has a faster deformation speed (bending speed of 37.6° / s) when subjected to external stimuli; finally, the gel prepolymer liquid can fully penetrate into the bamboo shoots, especially the PNIPAM network and the cellulose network of the bamboo shoots can form strong hydrogen bonds, so that the BSPH has a higher structural stability, no peeling occurs during various complex driving processes, and the original shape can be completely restored. On the other hand, the present invention introduces aniline black with high photothermal conversion efficiency and conductivity into the bamboo shoot composite hydrogel, and develops a smart hydrogel with dual functional synergy of fast photothermal response, complex driving performance and self-sensing function.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a high-strength anisotropic composite hydrogel based on a bamboo shoot bio-template, characterized in that: The following steps are involved: Bamboo shoot slices were pretreated with an ethanol solution; the slices were then immersed in a poly (N-isopropylacrylamide) hydrogel prepolymer solution and subjected to ultrasound. The slices were then taken out and placed in a mold for ultraviolet light polymerization and washed to obtain a heterogeneous interpenetrating network structure hydrogel. Finally, the heterogeneous interpenetrating network structure hydrogel was immersed in a nigrosine solution, subjected to ultrasound and washed to obtain a composite hydrogel. The poly (N-isopropylacrylamide) hydrogel prepolymer solution includes 1500 mg of monomer N-isopropylacrylamide, 50 mg of N,N-methyleneacrylamide, 50 mg of azobisisobutylamidine hydrochloride and 15 mL of water.

2. The method for preparing a high-strength anisotropic composite hydrogel based on a bamboo shoot bio-template according to claim 1, wherein The photopolymerization time was 10 min.

3. The method for preparing a high-strength anisotropic composite hydrogel based on a bamboo shoot bio-template according to claim 1, wherein The mass concentration of the ethanol solution is 50%.

4. The method for preparing a high-strength anisotropic composite hydrogel based on a bamboo shoot bio-template according to claim 1, wherein: The concentration of the nigrosine solution was 7 mg / mL.

5. A high-strength anisotropic composite hydrogel based on a bamboo shoot bio-template prepared according to the method according to any one of claims 1 to 4.

6. Use of the high-strength anisotropic composite hydrogel based on a bamboo shoot bio-template as described in claim 5 in the preparation of a photothermal drive-self-sensing dual-function synergistic bionic device material.

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