A nanocomposite, nanocomposite phase material, and methods of making and using the same

Abstract

The application provides a nanocomposite, a nanocomposite phase material and a preparation method and application thereof, and the preparation method of the nanocomposite comprises the following steps: (1) mixing and reacting iron calcium phosphate ion oligomers and a polyvinyl alcohol solution to obtain a composite glue; and (2) mixing and reacting the composite glue obtained in the step (1) with a nanosheet dispersion solution to form a nanocomposite. The iron calcium phosphate ion oligomers and the polyvinyl alcohol are introduced into the nanosheet interlayer, in the evaporation self-assembly process, the ion oligomers are in-situ inorganic ion polymerization under the regulation of the polyvinyl alcohol molecular chain, an organic-inorganic interpenetrating homogeneous network is formed through hydrogen bond and coordination bond interaction in the nanosheet interlayer, and thus a firm 'organic-inorganic homogeneous network' structure is constructed between adjacent nanosheets. The nanocomposite prepared by the method has high tensile strength and toughness.

Description

Technical Field

[0001] This invention belongs to the field of materials technology and relates to a nanocomposite material, a nanocomposite phase material, its preparation method and application. Background Technology

[0002] MXenes are a novel class of two-dimensional inorganic nanomaterials with ultra-high specific surface area and excellent mechanical properties, making them ideal building blocks for constructing high-performance nanocomposites. Researchers often combine MXene nanosheets with organic polymers to prepare a series of MXene nanocomposites with superior properties.

[0003] However, since these materials are assembled at the microscopic level by stacked nanosheets and interlayer crosslinking of polymers, their macroscopic mechanical properties depend on the interfacial interactions between the two-dimensional nanosheets and the polymer matrix. Although introducing organic polymers into the nanosheet layers to construct a series of chemical bonds such as hydrogen bonds, ionic bonds, and covalent bonds can enhance the interfacial crosslinking to some extent, the interaction between organic molecules and nanosheets alone has limited effect on improving the strength and toughness of the composite film. The resulting macroscopic materials generally have low toughness and fracture strain, limiting their application in structural engineering fields requiring high strength and toughness.

[0004] To further improve the strength and toughness of the composite film, researchers added inorganic ions such as Ca... 2+ Cu 2+ Fe 3+ Introducing inorganic ions into polymer networks can enhance the crosslinking strength of organic networks, but the crosslinking of inorganic ions forms discrete "dot-like" connections, lacking a continuous nanoscale reinforcing phase, which limits the improvement of material strength and toughness.

[0005] Therefore, it is essential to develop a new nanocomposite material. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a nanocomposite material, a nanocomposite phase material, its preparation method, and its application. This nanocomposite material exhibits excellent tensile strength and toughness.

[0007] To achieve this objective, the present invention adopts the following technical solution: One objective of this invention is to provide a method for preparing nanocomposite materials, comprising the following steps: (1) Mix calcium iron phosphate oligomer with polyvinyl alcohol solution and react to obtain composite adhesive; (2) The composite adhesive obtained in step (1) is mixed with the nanosheet dispersion and reacted to form a nanocomposite material.

[0008] Preferably, the preparation method of the calcium ferric phosphate ion oligomer in step (1) includes: using calcium chloride dihydrate as calcium source, ferric chloride hexahydrate as iron source, phosphoric acid as phosphorus source, and alcohol as solvent, reacting under the action of a capping agent to obtain the calcium ferric phosphate ion oligomer; Preferably, the capping agent is triethylamine; Preferably, the solvent includes any one or a combination of at least two of ethanol, ethylene glycol, or glycerol; Preferably, the molar ratio of calcium to iron in the calcium source and iron source is (2-3):1; Preferably, the molar ratio of calcium to phosphorus in the calcium source and phosphorus source is (1-2):1; Preferably, the concentration of the calcium source in the solvent is 0.001-0.1 mol / L; Preferably, the concentration of triethylamine in the solvent is 0.03-1 mol / L; Preferably, the reaction temperature is 20-30℃ and the reaction time is 6-24 h.

[0009] Preferably, the method for preparing the iron-calcium ion oligomer further includes: performing solid-liquid separation on the mixture obtained after the reaction; Preferably, the solid-liquid separation method is centrifugation; Preferably, the centrifugation rate is 6000-8000 rpm and the centrifugation time is 5-10 min.

[0010] Preferably, the average particle size of the iron-calcium phosphate oligomer in step (1) is 0.5-1 nm; Preferably, the concentration of the calcium iron phosphate oligomer in step (1) is 0.6-60 mg / ml; Preferably, the concentration of the polyvinyl alcohol solution in step (1) is 1-5 wt%; Preferably, the mass ratio of calcium iron phosphate oligomer to polyvinyl alcohol in the composite adhesive in step (1) is (1-2):6; Preferably, the reaction in step (1) is carried out under stirring conditions, the stirring rate is 1000-1500 rpm, and the stirring time is 3-6 h.

[0011] Preferably, the solute in the nanosheet dispersion in step (2) is nanosheets, and the solvent is water; Preferably, the nanosheet is a nanosheet with a surface rich in hydroxyl functional groups; Preferably, the nanosheets include any one or a combination of at least two of MXene nanosheets, vermiculite, or layered bimetallic hydroxides; Preferably, the MXene nanosheets have a thickness of 1-5 nm and a lateral dimension of 500-5000 nm.

[0012] Preferably, the mass ratio of the solute (including oligomers and polyvinyl alcohol) in the composite adhesive in step (2) to the nanosheets in the nanosheet dispersion is (5-7):(5-3); Preferably, the reaction in step (2) is carried out under stirring conditions; Preferably, the stirring rate is 1000-1500 rpm; Preferably, the reaction temperature in step (2) is 20-30℃ and the reaction time is 4-6 h.

[0013] Preferably, step (2) further includes drying the reactants after the reaction by evaporation self-assembly; Preferably, the drying temperature is 20-30℃ and the drying time is 72-96 h.

[0014] The second objective of this invention is to prepare nanocomposite materials according to the preparation method described in the first objective.

[0015] The third objective of this invention is to provide a method for preparing nanocomposite phase materials, the method comprising: The nanocomposite material prepared for at least one of the two objectives is bonded and laminated with a composite adhesive to obtain a nanocomposite phase material; wherein the composite adhesive is a composite adhesive prepared for one of the objectives. Preferably, the lamination pressure is 10-50 kPa and the lamination time is 12-48 h.

[0016] The fourth objective of this invention is to prepare nanocomposite phase materials according to the preparation method described in objective three.

[0017] The fifth objective of this invention is to apply the nanocomposite material described in objective two, or the nanocomposite phase material described in objective four, in the fields of tough components, protective materials, and flexible sensing materials.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: In this application, by introducing calcium iron phosphate ion oligomers and polyvinyl alcohol into the interlayer of nanosheets, the ion oligomers undergo in-situ inorganic ion polymerization under the regulation of the polyvinyl alcohol molecular chains during evaporation self-assembly, forming an organic-inorganic interpenetrating homogeneous network between the nanosheet layers through hydrogen bonds and coordination bonds. This constructs a robust "organic-inorganic homogeneous network" structure between adjacent nanosheets. The nanocomposite material prepared by this method exhibits high tensile strength and toughness. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the process flow for preparing MXene nanocomposites in Example 1; Figure 2 The image shows the flexibility test results of the MXene nanocomposite material prepared in Example 1. Figure 3 The tensile strength versus fracture strain curves of the MXene nanocomposite material prepared in Example 1 are shown below. Figure 4 A comparison of the mechanical properties of the MXene nanocomposites prepared in Example 1 and Comparative Example 1; Figure 5 This is a product image of the MXene nanocomposite phase material prepared in Example 4; Figure 6 The bending strength versus bending strain curve of the MXene nanocomposite phase material prepared in Example 4 is shown. Detailed Implementation

[0020] It should be understood that in the description of this invention, the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0021] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] Those skilled in the art should understand that the present invention necessarily includes the necessary pipelines, conventional valves and general pump equipment for achieving complete process, but the above content is not the main innovation of the present invention. Those skilled in the art can add layouts based on process flow and equipment structure selection, and the present invention does not make any special requirements or specific limitations in this regard.

[0023] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0024] In some embodiments, this application provides a method for preparing a nanocomposite material, comprising the following steps: (1) Mix calcium iron phosphate oligomer with polyvinyl alcohol solution and react to obtain composite adhesive; (2) The composite adhesive obtained in step (1) is mixed with the nanosheet dispersion and reacted to form a nanocomposite material.

[0025] In this application, by mixing composite adhesive with nanosheet dispersion, a robust "organic-inorganic homogeneous network" structure is constructed between nanosheet layers through evaporation-induced self-assembly, thereby improving the tensile strength and toughness of nanocomposite materials.

[0026] In some embodiments, the preparation method of the iron calcium ion oligomer in step (1) includes: using calcium chloride dihydrate as calcium source, ferric chloride hexahydrate as iron source, phosphoric acid as phosphorus source, and alcohol as solvent, reacting under the action of a capping agent to obtain iron calcium ion oligomer; In this application, by controlling the reaction of calcium and iron sources with phosphorus sources in an organic solvent and in the presence of triethylamine end-capping agent, ultra-small-sized (0.5-1 nm particle size) iron-calcium ion oligomers can be stably generated.

[0027] In some embodiments, the capping agent is triethylamine; In some embodiments, the solvent includes any one or a combination of at least two of ethanol, ethylene glycol, or glycerol; In some embodiments, the molar ratio of calcium to iron in the calcium source and iron source is (2-3):1, such as 2:1, 2.2:1, 2.5:1, 2.7:1, 3:1, etc.

[0028] In some embodiments, the molar ratio of calcium to phosphorus in the calcium source and phosphorus source is (1-2):1, such as 1:1, 1.2:1, 1.5:1, 1.7:1, 2:1, etc.

[0029] In some embodiments, the concentration of the calcium source in the solvent is 0.001-0.1 mol / L, for example 0.001 mol / L, 0.005 mol / L, 0.01 mol / L, 0.03 mol / L, 0.05 mol / L, 0.08 mol / L, 0.1 mol / L, etc. In some embodiments, the concentration of triethylamine in the solvent is 0.03-1 mol / L, for example 0.03 mol / L, 0.05 mol / L, 0.08 mol / L, 0.1 mol / L, 0.3 mol / L, 0.5 mol / L, 0.8 mol / L, 1 mol / L, etc. In some embodiments, the reaction temperature is 20-30°C (e.g., 20°C, 23°C, 25°C, 28°C, 30°C, etc.), and the reaction time is 6-24 h (e.g., 6 h, 10 h, 15 h, 20 h, 24 h, etc.).

[0030] In some embodiments, the method for preparing the iron-calcium phosphate oligomer further includes: performing solid-liquid separation on the mixture obtained after the reaction; In this application, centrifuging an alcohol solution of calcium iron phosphate ion oligomers yields a colloidal substance of calcium iron phosphate ion oligomers. Centrifugation removes the alcohol solvent, preventing subsequent mixing with a polyvinyl alcohol solution from causing polyvinyl alcohol precipitation and resulting in undesirable solid-liquid phase separation.

[0031] In some embodiments, the solid-liquid separation is performed by centrifugation; In some embodiments, the centrifugation rate is 6000-8000 rpm (e.g., 6000 rpm, 6500 rpm, 7000 rpm, 8000 rpm, etc.), and the centrifugation time is 5-10 min (e.g., 5 min, 7 min, 9 min, 10 min, etc.).

[0032] In some embodiments, the average particle size of the iron-calcium phosphate oligomer in step (1) is 0.5-1 nm; In this application, the obtained iron-calcium phosphate oligomers possess high reactivity due to their small size effect and high specific surface area, making them easy to interact with nanosheets and polymers, thus providing a basis for subsequent cross-linking polymerization reactions.

[0033] In some embodiments, the concentration of the iron calcium ion oligomer in step (1) is 0.6-60 mg / ml (e.g., 0.6 mg / ml, 10 mg / ml, 20 mg / ml, 30 mg / ml, 40 mg / ml, 50 mg / ml, 60 mg / ml, etc.). In some embodiments, the concentration of the polyvinyl alcohol aqueous solution in step (1) is 1-5 wt% (e.g., 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, etc.). In some embodiments, the mass ratio of calcium iron phosphate oligomer to polyvinyl alcohol in the composite adhesive in step (1) is (1-2):6 (e.g., 1:6, 1.2:6, 1.5:6, 1.8:6, 2:6, etc.). In some embodiments, the reaction in step (1) is carried out under stirring conditions, the stirring rate is 1000-1500 rpm (e.g., 1000 rpm, 1300 rpm, 1500 rpm, etc.), and the stirring time is 3-6 h (e.g., 3 h, 4 h, 5 h, 6 h, etc.).

[0034] In some embodiments, the solute in the nanosheet dispersion in step (2) is nanosheets, and the solvent is water; In some embodiments, the nanosheet is a nanosheet with a surface rich in hydroxyl functional groups; In some embodiments, the nanosheets include any one or a combination of at least two of MXene nanosheets, vermiculite, or layered bimetallic hydroxides; In this application, the surface of the nanosheet is rich in hydroxyl functional groups. As a highly reactive functional group, hydroxyl groups can form hydrogen bonds or covalent bonds with the polymer matrix (polyvinyl alcohol) and small molecule nanomaterials (oligomers) to build a stable interface and achieve the formation of an efficient stress transfer structure.

[0035] In some embodiments, the thickness of the MXene nanosheet is 1-5 nm (e.g., 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, etc.), and the lateral dimension is 500-5000 nm (e.g., 500 nm, 1000 nm, 2000 nm, 3000 nm, 4000 nm, 5000 nm, etc.).

[0036] In some embodiments, the mass ratio of the solute (including oligomer and polyvinyl alcohol) in the composite adhesive in step (2) to the nanosheets in the nanosheet dispersion is (5-7):(5-3); In this application, inorganic iron-calcium phosphate oligomers and organic polyvinyl alcohol are introduced into the interlayer of nanosheets, wherein the iron-calcium phosphate oligomers are rich in phosphate groups and Fe... 3+ It can form hydrogen bonds and coordination bonds with the hydroxyl groups on the nanosheets. The hydroxyl groups rich in polyvinyl alcohol can form hydrogen bonds with the nanosheets, thereby building multiple cross-linking effects between the nanosheet layers and improving the interfacial bonding strength.

[0037] In some embodiments, the reaction in step (2) is carried out under stirring conditions; In some embodiments, the stirring rate is 1000-1500 rpm (e.g., 1000 rpm, 1300 rpm, 1500 rpm, etc.). In some embodiments, the reaction temperature in step (2) is 20-30°C (e.g., 20°C, 23°C, 25°C, 28°C, 30°C, etc.), and the reaction time is 4-6 h (e.g., 4 h, 5 h, 6 h, etc.).

[0038] In some embodiments, step (2) further includes drying the reactants after the reaction by evaporation self-assembly; In this application, during the evaporation self-assembly drying process, the calcium iron phosphate ion oligomer undergoes in-situ inorganic ion polymerization under the regulation of the polyvinyl alcohol molecular chain, forming an organic-inorganic interpenetrating homogeneous network between the nanosheet layers. The inorganic network, organic network, and nanosheets interact through hydrogen bonds and coordination bonds, thereby constructing a robust "organic-inorganic homogeneous network" structure between adjacent nanosheets.

[0039] In some embodiments, the drying temperature is 20-30°C and the drying time is 72-96 h.

[0040] In some embodiments, this application provides a method for preparing a nanocomposite phase material, the method comprising: At least two prepared nanocomposite materials are bonded together with composite adhesive and laminated to obtain a nanocomposite phase material; In some embodiments, the lamination pressure is 10-50 kPa (e.g., 10 kPa, 15 kPa, 20 kPa, 25 kPa, 30 kPa, 35 kPa, 40 kPa, 45 kPa, 50 kPa, etc.), and the lamination time is 12-48 h (e.g., 12 h, 16 h, 20 h, 24 h, 28 h, 32 h, 36 h, 40 h, 44 h, 48 h, etc.).

[0041] Example 1 This embodiment provides a method for preparing nanocomposite materials, such as... Figure 1 As shown, it includes: (1) Preparation of calcium ferric phosphate oligomer: Prepare an ethanolic mixed solution of calcium chloride and ferric chloride. Dissolve 1.76 g of calcium chloride dihydrate and 1.08 g of ferric chloride hexahydrate in 400 mL of anhydrous ethanol. Add an ethanolic solution of phosphoric acid (0.63 mL of phosphoric acid dissolved in 10 mL of ethanol) and stir for 30 min. Add 33.36 mL of triethylamine, and then stir vigorously for 12 h. Obtain a yellow precipitate by centrifugation. After standing for 24 h, remove the supernatant to prepare a 12 mg / mL oligomer. -1Calcium iron phosphate oligomers.

[0042] (2) Preparation of nanocomposite materials: MXene nanocomposite materials were obtained by introducing an organic-inorganic composite adhesive, formed by mixing calcium iron phosphate ion oligomers with organic polymer polyvinyl alcohol, into the interlayer evaporation self-assembly of MXene nanosheets. First, 10 mL of a 12 mg / mL solution was taken. -1 The calcium iron phosphate oligomer was placed in a centrifuge tube and centrifuged at 6000 rpm for 5 min. The supernatant was discarded, and 20 mL of a 3.0 wt% polyvinyl alcohol aqueous solution was added and mixed thoroughly. The mixture was then transferred to a 50 mL beaker and stirred for 3 h to obtain an organic-inorganic composite adhesive. Subsequently, 30 mL of a 10 mg / mL solution was taken... -1 The MXene aqueous dispersion was placed in a 100 ml beaker, and 20 ml of well-mixed composite adhesive was slowly added. The mixture was vigorously stirred at 1500 rpm for 6 hours to form a homogeneous and stable slurry. The slurry was transferred to a 12 cm × 12 cm square petri dish, with the slurry depth controlled at approximately 5 mm. It was then placed in a vibration-free environment at 25°C for evaporation-induced self-assembly. After approximately 3 days, the solvent completely evaporated, and the self-supporting nanocomposite material was exfoliated from the petri dish.

[0043] Figure 2 The image shows the flexibility test results of the MXene nanocomposite material prepared in Example 1. Figure 2 It can be seen that the MXene nanocomposite material prepared in this embodiment has good bending, folding and load-bearing effects.

[0044] Figure 3 The tensile strength and fracture strain curves of the MXene nanocomposite material prepared in Example 1 are shown below. Figure 3 It can be seen that its tensile strength is 425.4 MPa and its fracture strain is 53.7%.

[0045] Figure 4 The graph shows the mechanical properties of the MXene nanocomposite material prepared in Example 1. Figure 4 It can be seen that the tensile strength of this MXene nanocomposite is 425.4 MPa and the toughness is 125.9 MJ / m. -3 .

[0046] Example 2 This embodiment provides a method for preparing a nanocomposite material, including: (1) Preparation of calcium ferric phosphate oligomer: Prepare an ethanolic mixed solution of calcium chloride and ferric chloride. Dissolve 0.059 g of calcium chloride dihydrate (calcium source concentration approximately 0.001 mol / L) and 0.054 g of ferric chloride hexahydrate (calcium-iron molar ratio approximately 2:1) in 400 mL of anhydrous ethanol. Add an ethanolic solution of phosphoric acid (0.032 mL of phosphoric acid dissolved in 10 mL of ethanol) and stir for 30 min. Add 1.67 mL of triethylamine (triethylamine concentration approximately 0.03 mol / L). Then, stir vigorously for 6 h. Obtain a yellow precipitate by centrifugation. After standing for 24 h, remove the supernatant to prepare a 0.6 mg / mL oligomer. -1 Calcium iron phosphate oligomers.

[0047] (2) Preparation of nanocomposite materials: Vermiculite nanocomposite materials are obtained by introducing an organic-inorganic composite adhesive, formed by mixing calcium iron phosphate ion oligomers with organic polymer polyvinyl alcohol, into the interlayer of vermiculite nanosheets for evaporative self-assembly. First, 200 mL of a 0.6 mg / mL solution was prepared. -1 The calcium iron phosphate oligomer was placed in a centrifuge tube and centrifuged at 7000 rpm for 8 min. The supernatant was discarded, and 60 mL of a 1.0 wt% polyvinyl alcohol aqueous solution was added and mixed thoroughly. The mixture was then transferred to a 100 mL beaker and stirred for 3 h to obtain an organic-inorganic composite adhesive. Subsequently, 30 mL of a 10 mg / mL solution was taken. -1 A dispersion of vermiculite nanosheets was placed in a 200 ml beaker, and 60 mL of a well-mixed composite adhesive was slowly added. The mixture was then vigorously stirred at 1000 rpm for 4 hours to form a homogeneous and stable slurry. The slurry was transferred to a 10 cm × 10 cm square petri dish, with the slurry depth controlled at approximately 5 mm. The dish was then placed in a vibration-free environment at 20°C to allow for evaporation-induced self-assembly. After approximately 3 days, the solvent completely evaporated, and the self-supported vermiculite nanocomposite material was exfoliated from the petri dish.

[0048] The nanocomposite material prepared in Example 2 was tested using the same methods as in Example 1, and the strength of Example 2 was found to be 255.7 MPa and the toughness was 74.1 MJ / m. -3 .

[0049] Example 3 This embodiment provides a method for preparing a nanocomposite material, including: (1) Preparation of calcium ferric phosphate oligomer: Prepare an ethanolic mixed solution of calcium chloride and ferric chloride. Dissolve 5.9 g of calcium chloride dihydrate (calcium source concentration approximately 0.1 mol / L) and 3.6 g of ferric chloride hexahydrate (calcium-iron molar ratio approximately 3:1) in 400 mL of anhydrous ethanol. Add an ethanolic solution of phosphoric acid (3.2 mL of phosphoric acid dissolved in 10 mL of ethanol) and stir for 30 min. Add 55.6 mL of triethylamine (triethylamine concentration approximately 1 mol / L). Then, stir vigorously for 24 h. Obtain a yellow precipitate by centrifugation. After standing for 24 h, remove the supernatant to prepare a 60 mg / mL oligomer. -1 Calcium iron phosphate oligomers.

[0050] (2) Preparation of nanocomposite materials: LDH nanocomposite materials are obtained by introducing an organic-inorganic composite adhesive formed by mixing calcium iron phosphate ion oligomers with organic polymer polyvinyl alcohol into the interlayer evaporation self-assembly of LDH nanosheets. First, take 2 mL of 60 mg / mL... -1 The calcium iron phosphate oligomer was placed in a centrifuge tube and centrifuged at 8000 rpm for 10 min. The supernatant was discarded, and 12 mL of a 5.0 wt% polyvinyl alcohol aqueous solution was added and mixed thoroughly. The mixture was then transferred to a 50 mL beaker and stirred for 3 h to obtain an organic-inorganic composite adhesive. Subsequently, 30 mL of a 10 mg / mL solution was taken. -1 The LDH nanosheet dispersion was placed in a 100 ml beaker, and 12 mL of well-mixed composite adhesive was slowly added. The mixture was then vigorously stirred at 1500 rpm for 6 hours to form a homogeneous and stable slurry. The slurry was transferred to a 13 cm × 13 cm square petri dish, with the slurry depth controlled at approximately 5 mm. The dish was then placed in a vibration-free environment at 30°C to induce evaporation-induced self-assembly. After approximately 3 days, the solvent completely evaporated, and the self-supporting LDH nanocomposite material was exfoliated from the petri dish.

[0051] The nanocomposite material prepared in Example 3 was tested using the same methods as in Example 1, and the strength of Example 3 was found to be 202.4 MPa, and the toughness was 86.3 MJ / m. -3 .

[0052] Comparative Example 1 The difference from Example 1 is that the preparation process does not include the addition of calcium iron phosphate ion oligomers. Instead, the subsequent film-forming steps are carried out directly using an aqueous dispersion of MXene nanosheets and a polyvinyl alcohol solution. The remaining steps and parameters are exactly the same as in Example 1.

[0053] The product prepared in Comparative Example 1 was subjected to the same tests as in Example 1, and the results showed that the strength of Comparative Example 1 was 107.9 MPa and the toughness was 6.37 MJ / m.-3 .

[0054] By comparing Example 1 and Comparative Example 1, such as Figure 4 As shown, the MXene nanocomposite material prepared in Example 1 exhibits high tensile strength (425.4 MPa) and ultra-high toughness (125.9 MJ / m²). -3 This is significantly higher than that of Comparative Example 1 (strength 107.9 MPa, toughness 6.37 MJ / m). -3 This indicates that the organic-inorganic homogeneous network structure formed by introducing calcium iron phosphate oligomers and using an interlayer inorganic ion polymerization strategy can effectively enhance the mechanical properties of materials.

[0055] Example 4 This embodiment provides a method for preparing nanocomposite phase materials, including: Preparation of nanocomposite phase materials: The MXene nanocomposite film (12 cm × 12 cm) prepared in Example 1 was immersed in deionized water to fully wet its surface. After removal, excess moisture was absorbed with lint-free paper. A layer of the prepared organic-inorganic composite adhesive was uniformly coated on the surface of each film, and then the layers were stacked one by one until the desired thickness (e.g., 30 layers) was achieved. The stacked preforms were placed between plates, and a constant pressure of 10 kPa was applied and maintained at 25°C for 24 hours. After depressurization, the samples were allowed to air dry at 25°C for 48 hours to obtain a structurally complete MXene nanocomposite phase material with tight interlayer bonding.

[0056] Figure 5 The image shows the MXene nanocomposite phase material prepared in Example 4, which is found to have a complete and dense interlayer structure.

[0057] Figure 6 The bending strength versus bending strain curves of the MXene nanocomposite phase material prepared in Example 4 show that its bending strength reaches 194.2 MPa and its bending energy is as high as 42.88 MJ / m². -3 .

[0058] Example 5 This embodiment provides a method for preparing a nanocomposite phase material, including: Preparation of nanocomposite phase materials: The vermiculite nanocomposite film (10 cm × 10 cm) prepared in Example 2 was immersed in deionized water to fully wet its surface. After removal, excess moisture was absorbed with lint-free paper. A layer of the prepared organic-inorganic composite adhesive was uniformly coated on the surface of each film layer, and then the layers were stacked one by one until the desired thickness (e.g., 15 layers) was achieved. The stacked preforms were placed between plates, and a constant pressure of 10 kPa was applied and maintained at 20°C for 48 hours. After depressurization, the samples were allowed to air dry at 20°C for 48 hours to obtain a structurally complete and compact vermiculite nanocomposite phase material.

[0059] The nanocomposite phase material prepared in Example 5 was tested using the same methods as in Example 4. The results showed that the flexural strength of Example 5 reached 164.6 MPa, and the flexural energy was as high as 36.32 MJ / m². -3 .

[0060] Example 6 This embodiment provides a method for preparing a nanocomposite phase material, including: Preparation of nanocomposite phase materials: The LDH nanocomposite film (13 cm × 13 cm) prepared in Example 3 was immersed in deionized water to fully wet its surface. After removal, excess moisture was absorbed with lint-free paper. A layer of the prepared organic-inorganic composite adhesive was uniformly coated on the surface of each film, and then the layers were stacked one by one until the desired thickness (e.g., 20 layers) was achieved. The stacked preforms were placed between plates, and a constant pressure of 50 kPa (pressure limit) was applied and maintained at 30°C for 12 hours. After depressurization, the samples were allowed to air dry at 30°C for 48 hours to obtain structurally complete LDH nanocomposite phase materials.

[0061] The nanocomposite phase material prepared in Example 6 was tested using the same methods as in Example 4. The results showed that the flexural strength of Example 6 reached 171.9 MPa, and the flexural energy was as high as 37.58 MJ / m². -3 .

[0062] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for producing a nanocomposite material, characterized by, The preparation method includes: (1) Mix calcium iron phosphate oligomer with polyvinyl alcohol solution and react to obtain composite adhesive; (2) The composite adhesive obtained in step (1) is mixed with the nanosheet dispersion and reacted to form a nanocomposite material.

2. The production method according to claim 1, characterized by, The preparation method of the calcium ferric phosphate ion oligomer in step (1) includes: using calcium chloride dihydrate as calcium source, ferric chloride hexahydrate as iron source, phosphoric acid as phosphorus source, and alcohol as solvent, reacting under the action of end-capping agent to obtain calcium ferric phosphate ion oligomer; Preferably, the capping agent is triethylamine; Preferably, the solvent includes any one or a combination of at least two of ethanol, ethylene glycol, or glycerol; Preferably, the molar ratio of calcium to iron in the calcium source and iron source is (2-3):1; Preferably, the molar ratio of calcium to phosphorus in the calcium source and phosphorus source is (1-2):1; Preferably, the concentration of the calcium source in the solvent is 0.001-0.1 mol / L; Preferably, the concentration of triethylamine in the solvent is 0.03-1 mol / L; Preferably, the reaction temperature is 20-30℃ and the reaction time is 6-24 h.

3. The preparation method according to claim 2, characterized in that, The method for preparing the iron calcium ion oligomer further includes: performing solid-liquid separation on the mixture obtained after the reaction; Preferably, the solid-liquid separation method is centrifugation; Preferably, the centrifugation rate is 6000-8000 rpm and the centrifugation time is 5-10 min.

4. The method of claim 1, wherein, The average particle size of the iron-calcium phosphate oligomers in step (1) is 0.5-1 nm; Preferably, the concentration of the calcium iron phosphate oligomer in step (1) is 0.6-60 mg / ml; Preferably, the concentration of the polyvinyl alcohol solution in step (1) is 1-5 wt%; Preferably, the mass ratio of calcium iron phosphate oligomer to polyvinyl alcohol in the composite adhesive in step (1) is (1-2):6; Preferably, the reaction in step (1) is carried out under stirring conditions, the stirring rate is 1000-1500 rpm, and the stirring time is 3-6 h.

5. The preparation method according to claim 1, characterized in that, In step (2), the solute in the nanosheet dispersion is nanosheets, and the solvent is water; Preferably, the nanosheet is a nanosheet with a surface rich in hydroxyl functional groups; Preferably, the nanosheets include any one or a combination of at least two of MXene nanosheets, vermiculite, or layered bimetallic hydroxides; Preferably, the MXene nanosheets have a thickness of 1-5 nm and a lateral dimension of 500-5000 nm.

6. The preparation method according to claim 1, characterized in that, In step (2), the mass ratio of the solute in the composite adhesive to the nanosheets in the nanosheet dispersion is (5-7):(5-3). Preferably, the reaction in step (2) is carried out under stirring conditions; Preferably, the stirring rate is 1000-1500 rpm; Preferably, the reaction temperature in step (2) is 20-30℃ and the reaction time is 4-6 h.

7. The preparation method according to claim 1, characterized in that, Step (2) also includes drying the reactants after the reaction; Preferably, the drying temperature is 20-30℃ and the drying time is 72-96 h.

8. The nanocomposite material is prepared by the preparation method according to any one of claims 1-7.

9. A nanocomposite phase material, characterized in that, The method for preparing the nanocomposite phase material includes: bonding at least two nanocomposite materials as described in claim 8 together with a composite adhesive and laminating them to obtain the nanocomposite phase material; wherein the composite adhesive is the composite adhesive prepared according to claim 6; Preferably, the lamination pressure is 10-50 kPa and the lamination time is 12-48 h.

10. The application of the nanocomposite material according to claim 8, or the nanocomposite phase material according to claim 9, in the fields of tough components, protective materials, and flexible sensing materials.

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