Continuous polymerization method of self-supply active substance, gel and application

Abstract

The invention belongs to the technical field of high polymer materials and polymerization, and particularly relates to a continuous polymerization method for self-supply of active substances, gel and application. According to the method, active filler such as liquid metal, barium titanate (BTO) or zinc oxide (ZnO) is introduced into a gel network as a built-in'reaction engine ', so that free radicals and / or metal ions can be spontaneously and continuously generated in a water or organic solvent environment. The self-supplied active substances drive the polymer network to carry out secondary chemical crosslinking and physical crosslinking for several weeks to several months, so that the dynamic evolution of the structure and performance of the gel material along with time is realized. The invention provides a brand-new technical platform for preparing the intelligent soft material with the long-time-history self-adaptive characteristic.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials and polymerization technology, and specifically relates to a new method for achieving continuous polymerization and cross-linking of gels after molding by using built-in active fillers. Background Technology

[0002] Gels are soft materials with a three-dimensional network structure, widely used in biomedicine, soft robotics, and other fields. Traditional gel synthesis relies on the one-time addition of monomers and initiators; once polymerization is complete, the network structure is essentially fixed, lacking the ability to dynamically evolve. This limits their application in scenarios requiring long-term adaptation and functional changes (such as scaffolds accompanying tissue growth in tissue engineering, and soft robots with learning capabilities).

[0003] Currently, strategies for endowing gels with dynamic properties primarily rely on external stimuli or the introduction of reactants. The dynamic behavior of these methods cannot be maintained without a continuous supply of external energy or matter, and their dynamic cycle is limited by the duration of the external stimulus or the kinetic rate of the reversible response, making it difficult to achieve long-term evolution spanning weeks to months. These limitations prevent existing dynamic gels from meeting the application requirements of cutting-edge fields such as tissue engineering scaffolds that need long-term autonomous evolution in stable physiological environments, or soft robots that require long-term environmental adaptability. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method for continuous polymerization of self-supplying active substances, as well as gels and applications, in order to solve the problem that the dynamic behavior of existing gels cannot be maintained without the continuous supply of external energy or substances, and that their dynamic cycle is limited by the duration of external stimulation or the kinetic rate of reversible reactions, thus making it difficult to achieve long-term evolution spanning from several weeks to several months.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A first aspect of the present invention provides a continuous polymerization method based on self-supplying active substances, comprising the following steps: It provides a mixture comprising monomers, solvents, and active fillers. The active filler is capable of spontaneously generating active substances in a solvent or triggered by external stimuli, which drive the continuous gel polymerization of the network. These active substances include free radicals, or both free radicals and metal ions. The monomer contains functional groups that can interact with the active substances released by the active filler, the interaction including polymerization or cross-linking with free radicals, or the interaction simultaneously including forming coordination bonds with metal ions and polymerization or cross-linking with free radicals; The mixture is subjected to preliminary polymerization to prepare an initial gel with continuous polymerization and crosslinking capabilities; The initial gel is placed in a solvent, where the active filler continuously generates active substances, which drive the gel network to undergo continuous polymerization and cross-linking reactions.

[0006] Optionally, the monomer has the structure shown in the following general formula (a): CH2=C(X)(Y)…general formula (a). Wherein: X is selected from H or C1-C6 alkyl groups; Y is selected from -C(=O)OR3, -C(=O)NR4R5, -C≡N, -Ph, -Ph-R6, -C(=O)OH, -CH2OH, -SH, -SO3H, -PO3H2 or heterocyclic groups; Wherein: R3 in -C(=O)OR3 is selected from C1-C 20 Alkyl, C3-C 20 cycloalkyl, C6-C 20 The aryl, polyethylene glycol, or hydroxyalkyl group; R4 and R5 in -C(=O)NR4R5 are each independently selected from H, C1-C 20 The alkyl, hydroxyalkyl, or R4 and R5 together with the N atom to which they are attached form a five-membered ring or a six-membered heterocycle; R6 in -Ph-R6 is selected from sulfonic acid group, phosphoric acid group, C1-C6 alkyl, halogen or hydroxyl group; the heterocyclic group is selected from pyrrolidone group, pyridinyl group, piperidinyl group, furanyl group or thiophene group.

[0007] Optionally, the active filler is at least one of liquid metal and piezoelectric material.

[0008] Optionally, the liquid metal is gallium micro / nano particles or gallium-indium alloy droplets, and the size range of the liquid metal is 10 nm-10 μm.

[0009] Optionally, the piezoelectric material is an inorganic piezoelectric material or an organic polymer piezoelectric material; wherein, the inorganic piezoelectric material is selected from at least one of lead titanate, barium titanate, lead zirconate titanate, zinc oxide, potassium niobate, lithium niobate, lithium tantalate, bismuth titanate, bismuth layered perovskite ferroelectric, tungsten bronze ferroelectric, bismuth ferrite, potassium dihydrogen phosphate, ammonium triglycate sulfate, Roche salt, lead magnesium niobate-lead titanate, strontium ruthenium oxide, perovskite-type organometal halide ferroelectric and doped compounds of the above materials, and the inorganic piezoelectric material is in the form of nanoparticles, nanowires, nanosheets or nanorods with a size range of 10 nm-5 μm; The organic polymer piezoelectric material is selected from at least one of polyvinylidene fluoride and polyacrylonitrile.

[0010] Optionally, the active filler accounts for 1%-60% of the mass percentage in the mixture.

[0011] Optionally, the initial gel is placed in a solvent after being photostimulated, or the initial gel is placed in a solvent and subjected to ultrasonic stimulation. The wavelength of the light is 400-1100 nm and the power density is 0.01-10 W / cm²; the frequency of the ultrasound is 10 kHz-10 MHz and the intensity is 0.01-20 W / cm².

[0012] Optionally, light or ultrasound can be used to locally stimulate the gel. By designing the spatiotemporal distribution parameters of the stimulation, the process of continuous cross-linking reaction inside the gel can be programmed to induce and control the gel to achieve a preset three-dimensional deformation over time scales ranging from hours to months.

[0013] By designing different lighting or ultrasound focusing patterns, the gel is induced to produce complex three-dimensional deformations, including bending, curling, twisting, and wrinkling.

[0014] A second aspect of the present invention provides a gel prepared by the method described in the present invention.

[0015] A third aspect of the present invention provides the application of the gel described herein in the preparation of tissue engineering scaffolds, soft robots, or bioelectronic devices.

[0016] The present invention has the following beneficial effects: 1. Self-supply driven: Through the built-in "reaction engine", it achieves continuous self-supply of active substances without the need for external supplementation.

[0017] 2. Continuous polymerization: It breaks through the time limitation of traditional gel polymerization and realizes the long-term and dynamic evolution of network structure.

[0018] 3. Controllable time scale: The polymerization and cross-linking process can last for weeks to months, matching the long time scale of many biological processes.

[0019] 4. Programmability: The continuous polymerization process can be spatiotemporally programmed using external stimuli, making it possible to prepare complex structural materials. Attached Figure Description

[0020] Figure 1 The stress-strain curves of the gallium composite hydrogel over 0-30 days are shown.

[0021] Figure 2 Photographs of the tube deformation and bending angle changes of the gallium composite hydrogel within 0-48 h.

[0022] Figure 3 Images of the helical deformation and bending angle changes of the gallium composite hydrogel over 0-39 days. Detailed Implementation The following embodiments are merely some, not all, of the embodiments of the present invention. Therefore, the detailed descriptions of the embodiments provided below are not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments. 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.

[0023] This invention provides a continuous polymerization method based on self-supplied active substances, comprising the following steps: Provides mixtures comprising monomers, solvents, and active fillers; The mixture is subjected to preliminary polymerization (which can be carried out at room temperature, with polymerization time such as 30 minutes, 2 hours, etc.) to prepare an initial gel with continuous polymerization and cross-linking capabilities; The initial gel is placed in a solvent (referring to a new solvent, i.e., a pure solvent without other components). In the solvent environment (such as an organic solvent or water), the active filler in the initial gel can spontaneously generate active substances that drive the continuous evolution of the network without the need for external supplementation of reactants, or after being triggered by external stimuli (such as light or ultrasound stimulation, the purpose of which is to promote polymerization and cross-linking reactions). The active substances include free radicals, or the active substances include both free radicals and metal ions. The active substances drive the gel network to undergo continuous polymerization and cross-linking reconstruction.

[0024] In this embodiment, monomers with specific structures are blended with active fillers in water or organic solvents and subjected to preliminary polymerization to form an initial gel with an initial network structure. Subsequently, under the triggering of external stimuli (such as light or ultrasound), the active fillers continuously generate active substances (including free radicals, or the active substances include both free radicals and metal ions) in an organic solvent or water environment to drive the continuous evolution of the network. These self-supplied active substances serve as an endogenous driving force, driving the formed gel network to undergo continuous secondary free radical polymerization and / or cross-linking reactions and coordination with metal ions, thereby achieving long-term, dynamic reconstruction and performance evolution of its chemical and physical cross-linked network.

[0025] In this embodiment, the continuous polymerization and cross-linking reconstruction process can last for hours, weeks or even months, thereby enabling the gel to evolve its structure and properties over a wide timescale.

[0026] The monomer has the structure shown in general formula (a): CH2=C(X)(Y)…General formula (a) in: X is selected from H or C1-C6 alkyl groups, for example, the C1-C6 alkyl groups may include straight-chain alkyl groups, branched alkyl groups or cycloalkyl groups; Y is selected from -C(=O)OR3, -C(=O)NR4R5, -C≡N, -Ph, -Ph-R6, -C(=O)OH, -CH2OH, SH, -SO3H, -PO3H2 or heterocyclic groups; Wherein: R3 in -C(=O)OR3 is selected from C1-C 20 Alkyl, C3-C 20 cycloalkyl, C6-C 20 Aryl, polyethylene glycol or hydroxyalkyl; In the -C(=O)NR4R5, R4 and R5 are each independently selected from H, Cl-C. 20 Alkyl, hydroxyalkyl, or R4 and R5 together with the N atom to which they are attached form a five-membered ring or a six-membered heterocycle; The R6 in -Ph-R6 is selected from sulfonic acid group, phosphoric acid group, C1-C6 alkyl group, halogen or hydroxyl group; The heterocyclic group is selected from pyrrolidone, pyridinyl, piperidinyl, furanyl, or thiophene.

[0027] The Y group in general formula (a) of this embodiment contains a functional group that can interact with the active substance released by the active filler. The interaction includes polymerization or cross-linking with free radicals, or the interaction includes both forming a coordination bond with metal ions and polymerization or cross-linking with free radicals.

[0028] Preferably, the monomer contains at least one molecule having at least two polymerizable groups represented by general formula (a). The polymerizable groups mainly fall into two categories: first, groups that can directly participate in chain growth reactions (such as olefin double bonds); and second, groups that can react during polymerization to form a cross-linked network (such as carboxyl, hydroxyl, and amino groups). A monomer molecule containing at least two polymerizable groups is selected, and a preliminary network is formed through the polymerization reaction of these polymerizable groups.

[0029] In one embodiment, the monomer has a total mass percentage in the mixture of 2%-98%, such as 2%, 5%, 10%, 20%, 40%, 55%, 60%, 80%, 90%, 98%, etc.

[0030] In one embodiment, the active filler is at least one of liquid metal and piezoelectric material.

[0031] When the active filler contains liquid metal, it continuously generates free radicals and releases metal ions through spontaneous oxidation in an aqueous or organic solvent environment. When the active filler contains piezoelectric materials, it continuously generates free radicals under mechanical stress through the piezoelectric effect.

[0032] The continuously generated free radicals initiate continuous secondary polymerization, crosslinking, or chain breakage rearrangement of the polymer network, thereby achieving continuous reconstruction of the chemical crosslinking network.

[0033] The continuously released metal ions can undergo continuous ionic coordination bonding with functional groups (such as carboxyl, amide, hydroxyl, mercapto, sulfonic acid, and phosphate groups) of the side chains in the polymer network, dynamically constructing a physically cross-linked network.

[0034] The free radical can be one or more of hydroxyl radicals and superoxide radicals, and the metal ion can be one or more of gallium ions, barium ions, zinc ions and lead ions.

[0035] Preferably, the liquid metal is gallium micro / nano particles or gallium-indium alloy droplets, and the size range of the liquid metal is 10 nm-10 μm, such as 10 nm, 100 nm, 500 nm, 1 μm, 2 μm, 5 μm, 10 μm, etc.

[0036] In one embodiment, the piezoelectric material is an inorganic piezoelectric material or an organic polymer piezoelectric material; wherein, the inorganic piezoelectric material is selected from at least one of lead titanate, barium titanate, lead zirconate titanate, zinc oxide, potassium niobate, lithium niobate, lithium tantalate, bismuth titanate, bismuth layered perovskite ferroelectric, tungsten bronze ferroelectric, bismuth ferrite, potassium dihydrogen phosphate, ammonium triglycate sulfate, Roche salt, lead magnesium niobate-lead titanate, strontium ruthenate, perovskite-type organometal halide ferroelectrics, and doped compounds of the above materials, and its morphology is nanoparticles, nanowires, nanosheets, or nanorods, with a size range of 10 nm-5 μm, such as 10 nm, 100 nm, 500 nm, 1 μm, 2 μm, 4 μm, 5 μm, etc. The organic polymer piezoelectric material is selected from at least one of polyvinylidene fluoride and polyacrylonitrile.

[0037] In one embodiment, the active filler has a mass percentage of 1%-60% in the mixture, such as 1%, 5%, 10%, 18%, 20%, 30%, 35%, 40%, 48%, 55%, 58%, 60%, etc.

[0038] In one embodiment, the mixture further comprises a crosslinking agent, such as N,N'-methylenebisacrylamide, polyethylene glycol diacrylate, etc.

[0039] In one embodiment, the method further includes using an external stimulus to trigger and modulate a self-sustaining response process within the device; the external stimulus includes light (such as near-infrared light) or ultrasound.

[0040] In one embodiment, the wavelength of the light is 400-1100 nm (e.g., 400 nm, 500 nm, 800 nm, 808 nm, 1100 nm, etc.), and the power density is 0.01-10 W / cm² (e.g., 0.01 W / cm², 0.1 W / cm², 0.5 W / cm², 1 W / cm², 2 W / cm², 5 W / cm², 10 W / cm², etc.); the frequency of the ultrasound is 10 kHz-10 MHz (e.g., 10 kHz, 100 kHz, 1000 kHz, 1 MHz, 5 MHz, 10 MHz, etc.), and the intensity is 0.01-20 W / cm² (e.g., 0.01 W / cm², 0.1 W / cm², 0.5 W / cm², 1 W / cm², 15 W / cm², 20 W / cm², etc.).

[0041] In one embodiment, light or ultrasound is used to locally stimulate the gel. By designing the spatiotemporal distribution parameters of the stimulation, the process of continuous cross-linking reaction inside the gel is programmed, thereby inducing and controlling it to achieve a preset three-dimensional deformation over time scales ranging from hours to months.

[0042] By designing different lighting or ultrasound focusing patterns, the gel is induced to produce complex three-dimensional deformations, including bending, curling, twisting, and wrinkling.

[0043] This invention provides a gel, which is prepared by the method described in this invention.

[0044] This invention provides an application of a gel in the preparation of tissue engineering scaffolds, soft robots, or bioelectronic devices.

[0045] The present invention will be further described in detail below through specific embodiments.

[0046] Example 1 0.9 g of gallium metal was added to 3 mL of methylcellulose aqueous solution (0.1 wt%), and after ultrasonic dispersion and centrifugation, gallium microparticles were obtained. 60 mg of gallium microparticles, 0.1 g of crosslinking agent N,N'-methylenebisacrylamide, and monomers (0.2 g acrylamide and 0.2 g methacrylic acid) were mixed in 1 mL of pure water and polymerized at room temperature for 30 minutes to successfully prepare a gallium composite hydrogel with continuous crosslinking ability (i.e., the initial gel).

[0047] To verify its sustained polymerization effect, the gallium composite hydrogel sample was cut into strips, and one end of the strip was irradiated with 808 nm near-infrared light (power density 2.0 W / cm²) for 1 minute. After irradiation, the strips were placed in pure water for continuous observation (without subsequent light treatment). Figure 1 The results showed that the cross-linking network of the hydrogel continued to evolve after the light exposure ended. From day 0 to day 30, the Young's modulus of the gel gradually increased (0.483 ± 0.022 MPa on day 0; 10.98 ± 0.49 MPa on day 15; and 38.7 ± 7.86 MPa on day 30, with significantly enhanced mechanical properties).

[0048] Example 2 Gallium composite hydrogel strips were prepared according to the method in Example 1. After being irradiated on one side with 808 nm near-infrared light (power density 2.0 W / cm²) for 1 minute, they were placed in pure water for long-term observation (without subsequent light treatment). The results showed that the internal crosslinking density of the hydrogel increased continuously and slowly over 0-39 days, fully demonstrating the continuous polymerization capability across time scales of the method of this invention. By designing different light patterns, the gallium composite hydrogel could undergo tube-like deformation within 48 hours, with the bending angle continuously increasing from 0° to 360°. Figure 2 In addition, spiral deformation can occur within 39 days, with the degree of curling gradually increasing over time. Figure 3 ).

[0049] Example 3 0.9 g of gallium metal was added to 3 mL of dimethyl sulfoxide (DMSO), and after ultrasonic dispersion and centrifugation, gallium microparticles were obtained. 60 mg of gallium microparticles, 0.1 g of crosslinking agent N,N'-methylenebisacrylamide, and monomers (0.2 g acrylamide and 0.2 g methacrylic acid) were blended in 1 mL of DMSO and polymerized at room temperature for 30 minutes to successfully prepare a gallium composite organic gel (i.e., the initial gel) with continuous crosslinking ability.

[0050] To verify its sustained polymerization effect in an organic solvent environment, the gallium composite organic gel sample was cut into strips, and one end of the strips was irradiated with 808 nm near-infrared light (power density 2.0 W / cm²) for 2 minutes. After irradiation, the strips were placed in pure DMSO for continuous observation (without subsequent light treatment). The organic gel exhibited sustained crosslinking characteristics similar to those of pure gallium filler, and its crosslinking network evolution continued throughout the 30-day observation period.

[0051] Example 4 60 mg of cubic barium titanate (BTO) nanoparticles were weighed and mixed with 0.1 g of crosslinking agent polyethylene glycol diacrylate and monomers (0.2 g acrylamide and 0.2 g acrylic acid) in 1 mL of pure water. Polymerization was carried out at room temperature for 30 minutes to prepare a BTO composite hydrogel (i.e., the initial gel). The resulting hydrogel strips were placed in pure water, and ultrasonic stimulation (20 kHz, 5 W / cm²) was applied to one side. 2 Under the alternating stress generated by ultrasonic vibration, the piezoelectric effect of BTO is activated, continuously generating free radicals, which in turn drive the polymer network to undergo slow and continuous chemical crosslinking reconstruction and volume change. This change further enhances the stress response of the piezoelectric material, promotes the generation of more free radicals, and forms a self-reinforcing cycling process. The polymerization reaction forms an initial gel within the first 30 minutes and continues for the next 28 days.

[0052] Example 5 60 mg of cubic barium titanate (BTO) nanoparticles were weighed and mixed with 0.1 g of crosslinking agent polyethylene glycol diacrylate and monomers (0.2 g acrylamide and 0.2 g acrylic acid) in 1 mL of dimethyl sulfoxide (DMSO). Polymerization was carried out at room temperature for 2 hours to prepare a BTO composite organic gel (i.e., the initial gel). The resulting organic gel strip was placed in pure DMSO and subjected to unilateral ultrasonic stimulation (20 kHz, 5 W / cm²). 2 Under the alternating stress generated by ultrasonic vibration, the piezoelectric effect of BTO is activated, continuously generating free radicals, which in turn drive the polymer network to undergo slow and continuous chemical crosslinking reconstruction and volume change. This change further enhances the stress response of the piezoelectric material, promotes the generation of more free radicals, and forms a self-reinforcing cyclic process. The polymerization reaction is initiated within the first 2 hours and continues for the next 28 days.

[0053] Example 6 0.9 g of gallium metal was added to 3 mL of methylcellulose aqueous solution (0.1 wt%), and after ultrasonic dispersion and centrifugation, gallium microparticles were obtained. 60 mg of gallium microparticles and 60 mg of barium titanate (BTO) nanoparticles were mixed at a mass ratio of 1:1, and then blended with 0.1 g of crosslinking agent polyethylene glycol diacrylate and monomers (0.2 g acrylamide and 0.2 g acrylic acid) in 1 mL of pure water to prepare a composite hydrogel. After unilateral irradiation with 808 nm near-infrared light (power density 2.0 W / cm²) for 1 minute, the hydrogel simultaneously triggered continuous crosslinking driven by gallium oxidation and initial crosslinking induced by the piezoelectric effect of BTO. After the light source was removed, the hydrogel further activated the piezoelectric effect of BTO during self-shrinkage, continuously generating free radicals and driving the polymerization reaction. This synergistic and self-sustaining polymerization mechanism caused the hydrogel's network structure to continuously densify over the next 30 days, macroscopically evolving from initial bending to a tight multi-turn helical structure.

[0054] In summary, this invention provides a method for continuous gel polymerization using self-supplying active substances, along with the gel and its applications. The method introduces active fillers such as liquid metals, barium titanate (BTO), or zinc oxide (ZnO) as built-in "reaction engines" into the gel network, enabling it to spontaneously and continuously generate free radicals (and simultaneously metal ions) in an aqueous or organic solvent environment. These self-supplying active substances drive the polymer network to undergo secondary chemical and physical crosslinking over several weeks to months, achieving dynamic evolution of the structure and properties of the gel material over time. This invention provides a novel technological platform for preparing smart soft materials with long-term adaptive properties.

[0055] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A continuous polymerization method based on self-supplied active substances, characterized in that, Includes the following steps: It provides a mixture comprising monomers, solvents, and active fillers. The active filler is capable of spontaneously generating active substances in a solvent or triggered by external stimuli, which drive the continuous gel polymerization of the network. These active substances include free radicals, or both free radicals and metal ions. The monomer contains functional groups that can interact with the active substances released by the active filler, the interaction including polymerization or cross-linking with free radicals, or the interaction simultaneously including forming coordination bonds with metal ions and polymerization or cross-linking with free radicals; The mixture is subjected to preliminary polymerization to prepare an initial gel with continuous polymerization and crosslinking capabilities; The initial gel is placed in a solvent, where the active filler continuously generates active substances, which drive the gel network to undergo continuous polymerization and cross-linking reactions.

2. The method according to claim 1, characterized in that, The monomer has the structure shown in the following general formula (a): CH2=C(X)(Y)…General formula (a). Wherein: X is selected from H or C1-C6 alkyl groups; Y is selected from -C(=O)OR3, -C(=O)NR4R5, -C≡N, -Ph, -Ph-R6, -C(=O)OH, -CH2OH, -SH, -SO3H, -PO3H2 or heterocyclic groups; Wherein: R3 in -C(=O)OR3 is selected from C1-C 20 Alkyl, C3-C 20 cycloalkyl, C6-C 20 The aryl, polyethylene glycol, or hydroxyalkyl group; R4 and R5 in -C(=O)NR4R5 are each independently selected from H, C1-C 20 The alkyl, hydroxyalkyl, or R4 and R5 together with the N atom to which they are attached form a five-membered ring or a six-membered heterocycle; R6 in -Ph-R6 is selected from sulfonic acid group, phosphoric acid group, C1-C6 alkyl, halogen or hydroxyl group; the heterocyclic group is selected from pyrrolidone group, pyridinyl group, piperidinyl group, furanyl group or thiophene group.

3. The method according to claim 1, characterized in that, The active filler is at least one of liquid metal and piezoelectric material.

4. The method according to claim 3, characterized in that, The liquid metal is gallium micro / nano particles or gallium-indium alloy droplets, and the size range of the liquid metal is 10 nm-10 μm.

5. The method according to claim 3, characterized in that, The piezoelectric material is an inorganic piezoelectric material or an organic polymer piezoelectric material; wherein, the inorganic piezoelectric material is selected from at least one of lead titanate, barium titanate, lead zirconate titanate, zinc oxide, potassium niobate, lithium niobate, lithium tantalate, bismuth titanate, bismuth layered perovskite ferroelectric, tungsten bronze ferroelectric, bismuth ferrite, potassium dihydrogen phosphate, ammonium triglycate sulfate, Roche salt, lead magnesium niobate-lead titanate, strontium ruthenium oxide, perovskite-type organometal halide ferroelectric and doped compounds of the above materials, and the inorganic piezoelectric material is in the form of nanoparticles, nanowires, nanosheets or nanorods with a size range of 10 nm-5 μm; The organic polymer piezoelectric material is selected from at least one of polyvinylidene fluoride and polyacrylonitrile.

6. The method according to claim 1, characterized in that, The active filler comprises 1%-60% by mass in the mixture.

7. The method according to claim 1, characterized in that, The initial gel is placed in a solvent after being photostimulated, or the initial gel is placed in a solvent and subjected to ultrasonic stimulation. The wavelength of the light is 400-1100 nm and the power density is 0.01-10 W / cm²; the frequency of the ultrasound is 10 kHz-10 MHz and the intensity is 0.01-20 W / cm².

8. The method according to claim 7, characterized in that, By using light or ultrasound to locally stimulate the initial gel, and by designing the spatiotemporal distribution parameters of the stimulation, the process of continuous cross-linking reaction inside the gel can be programmed to induce and control the gel to achieve a preset three-dimensional deformation across time scales ranging from hours to months. By designing different lighting or ultrasound focusing patterns, the gel is induced to produce complex three-dimensional deformations, including bending, curling, twisting, and wrinkling.

9. A gel prepared by any one of claims 1-8.

10. The use of the gel of claim 9 in the preparation of tissue engineering scaffolds, soft robots or bioelectronic devices.

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