Polyvinyl alcohol-based stab-resistant film and preparation method thereof

Abstract

The invention relates to the field of flexible protective materials, in particular to a polyvinyl alcohol-based stab-resistant film and a preparation method thereof. The polyvinyl alcohol-based stab-resistant film comprises a base film and reinforcing particles, the base film comprises polyvinyl alcohol and a polyphenol compound which are cross-linked with each other, the base film is provided with a first side face and a second side face opposite to the first side face, and the reinforcing particles are micron-sized hard materials and are doped in the base film. A rigid region is formed at a position adjacent to the second side of the base film. A solution method is combined with reinforced particle self-settling to form a rigid and flexible asymmetric puncture-proof film, so that the puncture-proof performance of a polyvinyl alcohol-based film material is improved, the flexibility is higher, and the application of the polyvinyl alcohol-based film material in the field of protection is facilitated.

Description

Technical Field

[0001] The present invention relates to the field of flexible protective materials, and in particular to a polyvinyl alcohol-based stab-proof film and a preparation method thereof. Background Art

[0002] Stab-resistant materials are materials that have the ability to resist attacks from sharp objects. Existing stab-resistant materials are typically rigid, such as metals, ceramics, and high-performance resins. While these materials offer excellent stab resistance, they also suffer from poor conformability and high density, making them unsuitable for applications requiring high flexibility and comfort. In contrast, flexible stab-resistant materials, such as high-performance fiber fabrics, offer excellent flexibility and comfort, but their stab resistance is relatively low, and their effectiveness is limited, particularly against sharp objects.

[0003] Polyvinyl alcohol (PVA) is a biodegradable material with excellent solid and liquid barrier properties. Its low density and good flexibility make it a promising material for protective clothing. However, PVA's poor stab resistance makes it susceptible to breakage in the presence of sharp objects, hindering its application in protective clothing. Summary of the Invention

[0004] The object of the present invention is to provide a polyvinyl alcohol-based stab-proof film having both high flexibility and stab-proof performance and a preparation method thereof.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A polyvinyl alcohol-based stab-proof film includes a base film and reinforcing particles. The base film includes cross-linked polyvinyl alcohol and a polyphenol compound, and the base film has a first side and a second side opposite to the first side. The reinforcing particles are micron-sized hard materials and are doped inside the base film to form a rigid area at a position adjacent to the second side of the base film.

[0007] Optionally, the mass ratio of the reinforcing particles to the polyvinyl alcohol-based stab-proof film is 1:(3.8-9.8) or any value thereof.

[0008] Optionally, the reinforcing particles include one or more of silica microspheres and graphene oxide flakes, the diameter of the silica microspheres is any value between 5 μm and 30 μm, and the lateral size of the graphene oxide flakes is any value between 3 μm and 30 μm.

[0009] Optionally, the polyphenol compound includes one or more of tannic acid, gallic acid, tea polyphenol, polyacrylic acid, acetylated tannic acid and sulfonated tannic acid.

[0010] Optionally, the polyphenol compound is tannic acid, and the mass ratio of the polyvinyl alcohol to the tannic acid in the base film is any value between (20 and 30):1.

[0011] Optionally, the puncture strength of the polyvinyl alcohol-based puncture-proof film is greater than or equal to 65 N / mm.

[0012] The present invention also provides a method for preparing the above-mentioned polyvinyl alcohol-based stab-proof film, comprising:

[0013] preparing the polyvinyl alcohol and the polyphenol compound into solutions respectively and mixing them with each other to obtain a mixed solution;

[0014] adding reinforcing particles to the mixed solution and performing a dispersion treatment to obtain a doping solution, wherein the reinforcing particles are insoluble in the mixed solution;

[0015] The doping liquid is poured into a mold, allowed to stand and settle for a first time, and then dried and film-formed to obtain the polyvinyl alcohol-based stab-proof film.

[0016] Optionally, the total mass fraction of the polyvinyl alcohol and the polyphenol compound in the mixed solution is less than or equal to 6 wt.%, and the first time is any value between 2 h and 24 h.

[0017] Optionally, the mixed solution is magnetically stirred for any value between 3h and 5h under the condition that the water bath temperature is any value between 75°C and 85°C, and then the reinforcing particles are added.

[0018] Optionally, the drying and film-forming treatment includes standing at a temperature of any value between 55° C. and 70° C. for any value between 5 hours and 8 hours.

[0019] The beneficial effects of the present invention lie in the fact that tannic acid (TA) and PVA are cross-linked through dynamic hydrogen bonds, forming a dynamic hydrogen bond network substrate, which imparts higher strength to the basement membrane compared to PVA films. Hard reinforcing particles are doped into the basement membrane to form a dense rigid region, creating a rigid-flexible asymmetric structure. This structure achieves synergistic protection under puncture loads through particle deflection cracking in the rigid layer, interfacial debonding, and viscoelastic energy dissipation in the flexible layer, significantly improving puncture strength and achieving a synergistic combination of rigidity and flexibility in the puncture-resistant material.

[0020] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a flow chart of a method for preparing a polyvinyl alcohol-based stab-proof film according to Example 1 of the present invention;

[0022] Figure 2 sectional electron micrographs of the polyvinyl alcohol-based stab-proof films in Example 1, Example 2, and Example 3 of the present invention;

[0023] Figure 3 Surface and cross-sectional electron micrographs of the polyvinyl alcohol-based stab-proof films in Examples 1 and 5 of the present invention;

[0024] Figure 4 This is a principle analysis diagram of the puncture process of the polyvinyl alcohol-based puncture-proof film in the present invention. DETAILED DESCRIPTION

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0028] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0029] The present invention applies to protect a polyvinyl alcohol-based stab-proof film, including a base film and reinforcing particles. The base film includes cross-linked polyvinyl alcohol and a polyphenol compound, and the base film has a first side and a second side opposite to the first side. The reinforcing particles are micron-level hard materials, which are doped inside the base film to form a rigid area at a position adjacent to the second side of the base film.

[0030] Polyphenol compounds have multiple phenolic hydroxyl groups, providing a large number of hydrogen bonding sites, forming a high-density cross-linked network with PVA, making the basement membrane stronger than the PVA film. The hydrogen bond network can be broken or reorganized, giving the material the potential for self-repair. Hard reinforcing particles are doped into the basement membrane to form a dense rigid region. At this time, the reinforcing particles and the hydrogen bond network together form a stronger three-dimensional network, forming a rigid-flexible asymmetric structure. This structure achieves synergistic protection under puncture loads through deflection cracks in the rigid layer particles, interface debonding, and viscoelastic energy dissipation in the flexible layer, significantly improving the puncture strength of the basement membrane and thus achieving the synergy between the rigidity and flexibility of the puncture-proof material.

[0031] In some embodiments, the mass ratio of the reinforcing particles to the polyvinyl alcohol-based stab-proof film is 1: any value in the range of (3.8 to 9.8), for example, it can be any value in the range of (1:3.8), (1:5.8), (1:7.8), and (1:9.8), which helps to balance the rigidity and flexibility of the polyvinyl alcohol-based stab-proof film.

[0032] In some embodiments, the reinforcing particles include one or more of silica microspheres and graphene oxide flakes. Both silica microspheres and graphene oxide flakes have great strength and rigidity, and can provide high puncture resistance. Silica microspheres have a regular spherical morphology, and graphene flakes have a large specific surface area. Both are easy to disperse, which helps to form a dense and dispersed rigid zone, thereby ensuring that the rigid zone has both flexibility and rigidity. In some embodiments, the diameter of the silica microspheres is any value between 5 μm and 30 μm, for example, it can be any value between 5 μm, 10 μm, 15 μm, 20 μm, 25 μm and 30 μm, and the lateral size of the graphene oxide flakes is any value between 3 μm and 30 μm, for example, it can be any value between 3 μm, 6 μm, 9 μm, 12 μm, 15 μm, 20 μm, 25 μm and 30 μm.

[0033] In some embodiments, the polyphenol compound includes one or more of tannic acid, gallic acid, tea polyphenols, polyacrylic acid, acetylated tannic acid, and sulfonated tannic acid. Selecting natural plant polyphenols and their derivatives as polyphenol compounds meets the biodegradability requirements of PVA-based materials. Structural modification of natural plant polyphenols facilitates adjustment of their properties to reduce process complexity. For example, acetylated tannic acid is highly hydrophobic, facilitating dehydration and film formation, while sulfonated tannic acid is highly water-soluble, facilitating the formation of cross-linked structures in solution.

[0034] In some embodiments, the polyphenol compound is tannic acid, and the mass ratio of polyvinyl alcohol to tannic acid in the basement membrane is any value between (20 and 30):1, for example, any value between (20:1), (22:1), (24:1), (26:1), (28:1), and (30:1). Tannic acid (TA) contains 25 hydroxyl groups, can provide a large number of hydrogen bonding sites, is easily degradable, and is readily available. Restricting the ratio of polyvinyl alcohol to tannic acid helps ensure sufficient cross-linking between the polyvinyl alcohol and tannic acid, thereby improving the puncture resistance of the basement membrane.

[0035] In some embodiments, the puncture strength of the polyvinyl alcohol-based puncture-resistant film is greater than or equal to 65 N / mm, for example, it can be any value among 65 N / mm, 70 N / mm, 75 N / mm, 80 N / mm, 85 N / mm, 90 N / mm and 92 N / mm.

[0036] The present invention claims a method for preparing the above-mentioned polyvinyl alcohol-based stab-proof film, comprising:

[0037] S1. Prepare polyvinyl alcohol and a polyphenol compound into solutions respectively and mix them with each other to obtain a mixed solution.

[0038] S2. Add reinforcing particles to the mixed solution and perform dispersion treatment to obtain a doped solution, wherein the reinforcing particles are insoluble in the mixed solution.

[0039] S3. Pour the doped liquid into a mold, let it stand for a first period of time, and then dry it to form a film to obtain a polyvinyl alcohol-based anti-stab film.

[0040] The rigid region is formed by a solution method combined with a self-sedimentation method after sufficient dispersion. The method is simple and can effectively form a densely doped rigid region, so that the rigid region has both flexibility and rigidity.

[0041] In some embodiments, the total mass fraction of polyvinyl alcohol and polyphenol compounds in the mixed solution is less than or equal to 6 wt.%, for example, 2 wt.%, 3 wt.%, 4 wt.%, 5 wt.%, and 6 wt.%. The first time is any value between 2 hours and 24 hours, for example, any value between 2 hours, 6 hours, 12 hours, 18 hours, and 24 hours. By restricting the concentration of the doping solution, it helps to ensure that the doping solution has appropriate viscosity, which facilitates enhanced dispersion and sedimentation of the particles. Restricting the sedimentation time helps to balance the rigidity and flexibility of the rigid region.

[0042] In some embodiments, the mixed solution is magnetically stirred for any value between 3 hours and 5 hours under the condition of a water bath temperature of any value between 75° C. and 85° C. The water bath temperature can be, for example, any value between 75° C., 77° C., 79° C., 81° C., 83° C., and 85° C., and then the reinforcing particles are added. The magnetic stirring time is any value between 3 hours, 3.5 hours, 4 hours, 4.5 hours, and 5 hours, which facilitates sufficient crosslinking of the polyphenol compound and the polyvinyl alcohol.

[0043] In some embodiments, the drying film-forming process includes standing at a temperature of 55° C. to 70° C. for 5 to 8 hours. The drying temperature can be, for example, 55° C., 60° C., 65° C., and 70° C., and the drying time can be 5 hours, 6 hours, 7 hours, and 8 hours.

[0044] Please refer to the following examples for details.

[0045] Example 1:

[0046] See Figure 1 The method for preparing a polyvinyl alcohol-based stab-proof film shown in a preferred embodiment of the present application includes:

[0047] S1. Prepare polyvinyl alcohol and a polyphenol compound into solutions respectively and mix them with each other to obtain a mixed solution.

[0048] S2. Add reinforcing particles to the mixed solution and perform dispersion treatment to obtain a doped solution, wherein the reinforcing particles are insoluble in the mixed solution.

[0049] S3. Pour the doped liquid into a mold, let it stand for a first period of time, and then dry it to form a film to obtain a polyvinyl alcohol-based anti-stab film.

[0050] Step S1 includes:

[0051] S110. Take 2.1 g of PVA and add it to 40 g of deionized water. Stir it magnetically in an 80° C. water bath for 4 h to fully dissolve it, thereby obtaining a 5 wt.% polyvinyl alcohol aqueous solution.

[0052] S120. Dissolve TA in deionized water and stir the mixture magnetically at room temperature for 1 h to prepare a 1 wt.% tannic acid aqueous solution.

[0053] S130. Mix the polyvinyl alcohol aqueous solution and the tannic acid aqueous solution in a proportioned manner to obtain a mixed solution such that the mass ratio of PVA to TA in the mixed solution is 25:1. The total mass of the mixed solution is approximately 50.5 g, of which the total mass of PVA and TA is 2.284 g. The mixture is magnetically stirred in an 80°C water bath for 4 hours to fully crosslink the polyvinyl alcohol and tannic acid.

[0054] In step S2, 0.51 g of SiO2 microspheres with an average diameter of 30 μm were added to the fully cross-linked mixed solution as reinforcing particles, and magnetic stirring was performed for 2 h to break up the agglomeration and make the particles evenly dispersed. The solution was then vibrated using an ultrasonic cleaner to eliminate internal bubbles to obtain a doping solution.

[0055] In step S3, the solution is poured into a mold and allowed to stand for 12 hours to allow the particles to complete self-sedimentation under the induction of gravity. Finally, the mixed solution is placed in an oven at 60°C for 6 hours to dry into a film to obtain a polyvinyl alcohol-based anti-stab film.

[0056] The polyvinyl alcohol-based stab-resistant film in this embodiment was weighed to have a total mass of approximately 2.8 g and a total thickness of 0.3 mm. A puncture resistance test was conducted by piercing the second surface of the polyvinyl alcohol-based stab-resistant film adjacent to the rigid region with a needle, and the puncture strength was found to be approximately 81.79 N / mm.

[0057] Example 2:

[0058] The only difference between this embodiment and the first embodiment is that in step S3 of this embodiment, the film is dried directly without static settling. The polyvinyl alcohol-based stab-resistant film of this embodiment was tested for its stab resistance, and its puncture strength was found to be approximately 62.79 N / mm.

[0059] Example 3:

[0060] The only difference between this embodiment and the first embodiment is that the settling time in step S3 of this embodiment is 24 hours. The polyvinyl alcohol-based stab-resistant film of this embodiment was tested for stab resistance, and its puncture strength was found to be approximately 68.34 N / mm. In this case, the density of the reinforcing particles in the rigid layer is high, but the rigid layer thickness is small, which is not conducive to stab resistance.

[0061] Example 4:

[0062] The only difference between this embodiment and Example 1 is that the total mass of the reinforcing particles in step S2 of this embodiment is adjusted to 0.77g and 0.25g, respectively. The mass ratios of the reinforcing particles to the base film are now approximately 1:3.8 and 1:9.8, respectively. The polyvinyl alcohol-based stab-resistant films of this embodiment were tested for puncture resistance. The results showed that after adding 0.25g of reinforcing particles, the puncture strength of the polyvinyl alcohol-based stab-resistant films was approximately 68.29 N / mm, and after adding 0.77g of reinforcing particles, the puncture strength of the polyvinyl alcohol-based stab-resistant films was approximately 76.74 N / mm.

[0063] By comparison, it can be seen that as the total mass of the doped reinforcing particles increases, the puncture strength of the polyvinyl alcohol-based puncture-resistant film first increases and then decreases, reaching a maximum value when the mass ratio of reinforcing particles to base film is approximately 1:5.3. This is because within a certain concentration range, the concentration of reinforcing particles is positively correlated with the thickness of the rigid zone and the surface hardness of the film, and the three-dimensional stress transfer network constructed by the particles in the hard layer improves the stress transfer efficiency and enhances puncture resistance. However, when the concentration of reinforcing particles exceeds a critical value, micron-sized aggregates are easily formed between the particles, which destroys the spatial distribution uniformity of the particles and weakens the particle-matrix interface bonding strength, which is not conducive to improving the puncture resistance performance.

[0064] Embodiment 5:

[0065] This embodiment differs from the first embodiment only in that the reinforcing particles in step S2 of this embodiment are SiO2 microspheres with an average diameter of 5 μm. The polyvinyl alcohol-based stab-resistant film in this embodiment was tested for puncture resistance, and its puncture strength was found to be approximately 91.49 N / mm. This indicates that reducing the diameter of the reinforcing particles improves puncture resistance.

[0066] Example 6:

[0067] This embodiment differs from Example 1 only in that the reinforcing particles in step S2 of this embodiment include 0.3g of SiO2 microspheres with an average diameter of 30μm and 0.22g of graphene oxide flakes with a lateral dimension of 5μm. The polyvinyl alcohol-based stab-resistant film in this embodiment was tested for its puncture resistance, and its puncture strength was found to be approximately 82.01N / mm.

[0068] Comparative Example 1:

[0069] The only difference between this comparative example and Example 1 is that no reinforcing particles are added in step S2 of this example to obtain a base film. The base film in this comparative example was tested for puncture resistance, and its puncture strength was found to be approximately 60.73 N / mm.

[0070] The cross sections of the polyvinyl alcohol-based stab-proof films obtained in Examples 1 to 5 were observed using an electron microscope. Figure 2, comparing the cross-sectional images of the polyvinyl alcohol-based anti-stab films obtained in Example 1, Example 2, and Example 3, it can be seen that the cross-sectional images of the anti-stab film exhibit rough characteristics throughout the thickness direction when no deposition is performed, while after deposition and subsequent drying, an obvious particle deposition phenomenon can be observed. The texture transitions from smooth to rough in the direction of particle deposition, and a phase separation interface appears. The smooth and rough areas are the flexible layer and rigid layer of the polyvinyl alcohol-based anti-stab film, respectively, forming a double-layer structure. Compared with the polyvinyl alcohol-based anti-stab films obtained in Example 1 and Example 3, the polyvinyl alcohol-based anti-stab film obtained in Example 2 exhibits a uniform phase separation structure, showing alternating rough and smooth areas. This structural evolution stems from different degrees of particle self-sedimentation. By comparison, it can be seen that after 12 hours of deposition, the particles self-assemble into a tightly packed rigid layer in the matrix, and the polyvinyl alcohol-based anti-stab film exhibits the best performance at this time.

[0071] The composition of the polyvinyl alcohol-based stab-proof film was detected by Fourier transform infrared (FTIR) spectroscopy. The part without reinforcing particles was taken for detection. It can be seen that the characteristic peak of TA exists alone, and the hydroxyl stretching vibration peak of PVA is shifted, but no new chemical bond peak appears, indicating that PVA and TA are only connected by hydrogen bonds and no chemical reaction occurs.

[0072] The morphology of the second surface of the polyvinyl alcohol-based stab-proof film obtained in Example 1 and Example 5 was observed and compared by electron microscopy, and combined with its cross-sectional image and local magnified image, see Figure 3 , it can be seen that as the size of the reinforcing particles decreases, they are distributed more densely in the matrix film, thus forming a denser rigid layer in the structure.

[0073] In addition, the morphology of the reinforcing particles near the puncture position formed in the puncture resistance test in the cross-sectional electron micrographs was observed, and no phenomenon of the reinforcing particles being damaged by the needle was found. This indicates that during the puncture process, the reinforcing particles dissipated energy through deflection and slippage, thereby resisting the movement of the needle.

[0074] For an analysis of the principle of the polyvinyl alcohol-based puncture-proof film in the present invention, please refer to Figure 4When a needle penetrates a polyvinyl alcohol-based puncture-resistant film, it undergoes four stages. The first stage is the elastic contact phase, during which the needle directly contacts the second surface. The rigid layer absorbs most of the energy, while the flexible layer dissipates some of the energy through slight bending deformation. The second stage is the rigid blocking phase, during which the needle enters the rigid layer formed by the non-agglomerated reinforcing particles doped within the base film. The needle collides with the numerous reinforcing particles. The three-dimensional network formed by the reinforcing particles and the base film allows for rapid and efficient stress transmission through the particles, increasing friction and hindering needle penetration. Simultaneously, crack deflection caused by the debonding of the reinforcing particles from the base film creates more microcracks, dissipating even more energy. When the needle reaches the microinterface between the rigid and flexible layers, the cracks created by the needle deflect and branch, enhancing energy dissipation. The third stage is the flexible blocking phase, during which the needle passes through the rigid layer and into the flexible layer. The rigid layer's resistance to the needle decreases, and molecular chain breakage becomes the primary method for dissipating energy and resisting the needle's advance, until the needle completely penetrates the film. During this phase, both the rigid and flexible layers directly impact the needle, resulting in maximum penetration strength. The fourth stage is the friction blocking period, in which the needle tip completely penetrates the anti-puncture film. However, due to the thin needle tip and thick needle body, there is friction between the anti-puncture film and the needle, which still has a blocking effect on the needle.

[0075] The beneficial effect of the present invention is that it provides a polyvinyl alcohol-based stab-proof film that is both rigid and flexible and has strong puncture-proof ability, which has high practical value in the fields of protective clothing and the like.

[0076] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0077] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A polyvinyl alcohol-based stab-proof film, characterized in that: The invention comprises a base film and reinforcing particles, wherein the base film comprises cross-linked polyvinyl alcohol and polyphenol compounds, and the base film has a first side and a second side opposite to the first side, and the reinforcing particles are micron-sized hard materials, which are doped inside the base film to form a rigid area at a position adjacent to the second side of the base film.

2. The polyvinyl alcohol-based stab-proof film according to claim 1, wherein: The mass ratio of the reinforcing particles to the polyvinyl alcohol-based stab-proof film is 1:(3.8-9.8) or any value thereof.

3. The polyvinyl alcohol-based stab-proof film according to claim 2, wherein: The reinforcing particles include one or more of silica microspheres and graphene oxide flakes. The diameter of the silica microspheres is any value between 5 μm and 30 μm, and the lateral size of the graphene oxide flakes is any value between 3 μm and 30 μm.

4. The polyvinyl alcohol-based stab-proof film according to claim 1, wherein: The polyphenol compound includes one or more of tannic acid, gallic acid, tea polyphenol, polyacrylic acid, acetylated tannic acid and sulfonated tannic acid.

5. The polyvinyl alcohol-based stab-proof film according to claim 4, wherein: The polyphenol compound is tannic acid, and the mass ratio of the polyvinyl alcohol to the tannic acid in the base film is any value between (20 and 30):

1.

6. The polyvinyl alcohol-based stab-proof film according to claim 1, wherein: Its puncture strength is greater than or equal to 65N / mm.

7. A method for preparing a polyvinyl alcohol-based stab-proof film according to any one of claims 1 to 6, characterized in that: include: preparing the polyvinyl alcohol and the polyphenol compound into solutions respectively and mixing them with each other to obtain a mixed solution; adding reinforcing particles to the mixed solution and performing a dispersion treatment to obtain a doping solution, wherein the reinforcing particles are insoluble in the mixed solution; The doping liquid is poured into a mold, allowed to stand and settle for a first time, and then dried and film-formed to obtain the polyvinyl alcohol-based stab-proof film.

8. The method for preparing the polyvinyl alcohol-based stab-proof film according to claim 7, wherein: The total mass fraction of the polyvinyl alcohol and the polyphenol compound in the mixed solution is less than or equal to 6 wt.%, and the first time is any value between 2 hours and 24 hours.

9. The method for preparing a polyvinyl alcohol-based stab-proof film according to claim 7, wherein: The mixed solution is magnetically stirred for any value between 3 hours and 5 hours under the condition that the water bath temperature is any value between 75° C. and 85° C., and then the reinforcing particles are added.

10. The method for preparing a polyvinyl alcohol-based stab-proof film according to claim 7, wherein: The drying film-forming treatment includes leaving the film at rest at a temperature of 55° C. to 70° C. for 5 hours to 8 hours.

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