Preparation method of thermoplastic polyimide composite spiral wound layer type IV gas cylinder

Abstract

This invention belongs to the field of pressure vessel and hydrogen energy technology, and discloses a method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer. The method involves preparing a monomer resin solution using dianhydride and diamine monomers, placing it in an impregnation tank, and then transversely penetrating it with continuous fiber bundles. Heating causes in-situ amidation polymerization to form a polyamic acid prepreg, which is then wound onto the surface of the Type IV plastic gas cylinder liner. Heating is then used to produce thermoplastic polyimide, and airtightness testing is performed. This invention proposes a method for impregnating fibers with polyimide monomers, which effectively improves the degree of fiber impregnation, thereby significantly enhancing the strength and reliability of the entire gas cylinder. Compared to the original process, the improved process is less complex, reduces resin performance degradation, and improves preparation efficiency. Both the gas cylinder liner and the winding layer resin matrix are made of thermoplastic resin, which is recyclable and meets national environmental protection policy requirements. The gas cylinder liner is made of plastic, and the working pressure can reach 35 MPa.

Description

Technical Field

[0001] This invention belongs to the field of pressure vessel and hydrogen energy technology, and particularly relates to a method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer. Background Technology

[0002] Currently, hydrogen, as a recognized clean energy source, has experienced rapid development in recent years. Compared to traditional fossil fuels such as oil, natural gas, and coal, the product of hydrogen combustion is water, and there are no emissions of nitrogen oxides or carbon dioxide. It has significant advantages in improving air quality and saving energy and reducing emissions, which has prompted countries around the world to vigorously develop the hydrogen energy industry.

[0003] Traditional gas cylinders are typically made of metal, which is not only heavy and increases the difficulty of transportation, but also prone to corrosion and breakage. If hydrogen leaks, it can easily explode, posing a significant safety risk. To meet the requirements of lightweight, high strength, and durability, continuous fiber-reinforced thermosetting composites have experienced rapid development and gained widespread acceptance. However, the recycling and reuse of thermosetting composites remains a persistent challenge hindering the industry's further development.

[0004] Continuous fiber reinforced thermoplastic composites offer advantages such as high molding efficiency, secondary molding capability, and recyclability, making them an effective solution to recycling and reuse issues, and have experienced rapid development in recent years. Furthermore, these composites exhibit good environmental aging resistance, high fatigue strength, and high impact damage tolerance, meeting the high damage tolerance requirements for airworthiness certification in the aerospace industry. In addition, compared to thermosetting prepregs, thermoplastic prepregs can be stored at room temperature for extended periods. Traditional thermoplastic composite winding processes require the pre-preparation of thermoplastic prepreg tapes, a cumbersome process that wastes manpower and resources. Moreover, the large molecular weight and high melt viscosity of thermoplastic polymers make impregnation of the prepreg tapes difficult; repeated heating and cooling can lead to degradation of the resin matrix properties, affecting the overall structural performance. Therefore, there is an urgent need to design a new method for preparing Type IV gas cylinders with thermoplastic polyimide composite winding layers.

[0005] Based on the above analysis, the problems and shortcomings of the existing technology are as follows:

[0006] (1) Traditional thermoplastic composite winding process requires the pre-preparation of thermoplastic prepreg tape, which is complicated and wastes manpower and resources.

[0007] (2) Thermoplastic polymers have large molecular weights and high melt viscosity, making it difficult to impregnate prepreg tapes.

[0008] (3) Repeated heating and cooling will cause the resin matrix to degrade and affect the overall structural performance.

[0009] (4) The thermoplastic prepreg tape winding process has high requirements for equipment automation. Currently, the mainstream prepreg tape heating methods (such as laser heating) are expensive and have poor interlayer bonding performance.

[0010] (5) During the compaction process of the thermoplastic prepreg tape winding process, the fiber is prone to in-plane buckling deformation, which can lead to manufacturing defects. Summary of the Invention

[0011] To address the problems existing in the prior art, this invention provides a method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer.

[0012] This invention is achieved by providing a method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer, the method comprising:

[0013] After preparing a monomer resin solution using dianhydride monomer and diamine monomer, the solution is placed in an impregnation tank, and continuous fiber bundles are used to penetrate laterally to ensure sufficient fiber impregnation. The fiber bundles are heated to induce in-situ amidation polymerization to form a polyamic acid prepreg, which is then wound onto the surface of the inner liner of a type IV plastic gas cylinder. The winding layer is further heated to react and generate a fiber-reinforced thermoplastic polyimide reinforcing layer, thus obtaining a type IV gas cylinder, which is then subjected to airtightness testing.

[0014] Furthermore, the method for preparing the thermoplastic polyimide composite winding layer type IV gas cylinder includes the following steps:

[0015] Step 1: Prepare a monomer resin solution mixture for the preparation of thermoplastic polyimide, which is used for fiber impregnation and preparation of polyamic acid prepreg;

[0016] Step 2: A continuous fiber bundle is transversely inserted into an impregnation tank containing the monomer resin solution mixture to obtain a monomer solution impregnated material. This method can ensure that the fibers are fully impregnated.

[0017] Step 3: The monomer solution impregnating material is heated at a certain temperature to remove residual organic solvents and then subjected to in-situ amidation polymerization to form polyamic acid prepreg. The prepreg is fully impregnated and has a certain viscosity, making it suitable for winding processes.

[0018] Step 4: Using a variety of winding angle combinations, the polyamic acid prepreg is wound onto the surface of the inner liner of the inflatable Type IV plastic gas cylinder to obtain a winding structure;

[0019] Step 5: Increase the temperature of the winding structure. The amyl acid in the polyamic acid prepreg undergoes an imidization reaction upon heating to produce thermoplastic polyimide, thereby improving the strength of the winding layer within and between layers.

[0020] Step six: Perform an airtightness test on the thermoplastic polyimide structure to obtain a Type IV gas cylinder with a thermoplastic polyimide composite winding layer.

[0021] Furthermore, the polyimide monomer resin solution mixture in step one includes dianhydride monomer and diamine monomer.

[0022] The dianhydride monomer of the polyimide monomer is selected from any one or a mixture of two or more of the following dianhydride monomers: pyromellitic dianhydride, isomerized biphenyltetracarboxylic dianhydride, isomerized 4,4'-oxydiphthalic anhydride, isomerized triphenyl diether tetracarboxylic dianhydride, benzophenone dianhydride, 2,2'-bis[4-(3,4-carboxyphenoxy)benzene]propane dianhydride, 4,4'-(hexafluoroisopropyl)diphthalic anhydride, cyclobutane dianhydride, cyclohexane dianhydride, and dicyclopentadiene dianhydride.

[0023] The dianhydride monomer of the polyimide monomer is selected from any one or a mixture of two or more of the following diamine monomers: p-phenylenediamine, m-phenylenediamine, mesitylene-m-phenylenediamine, 2,2'-dimethylbenzidine, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 2,2'-bis(trifluoromethylbenzidine), 4,4'-diaminodiphenylmethane, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, etc. Diphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,4-bis(2-trifluoromethyl-4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 4,4'-bis(3-aminophenoxy)diphenyl sulfone, 9,9-bis(4-aminophenyl)fluorene, 9,9-bis[4-(aminophenoxy)phenyl]fluorene.

[0024] Furthermore, the continuous fiber bundle in step two is selected from one or more of continuous glass fibers, aramid fibers, basalt fibers, PBO fibers, carbon fibers, natural fibers, and ultra-high molecular weight polyethylene fibers.

[0025] Furthermore, the heating temperature in step three is 100–150°C, preferably 110–140°C; the heating time is 3–60 min, preferably 5–50 min.

[0026] Furthermore, the winding angle combination in step four includes one or more combinations of helical winding, circumferential winding, and longitudinal winding.

[0027] Furthermore, the plastic cylinder liner material in step four includes general-purpose plastics such as polypropylene, polyethylene, polystyrene, and polyvinyl chloride; engineering plastics such as polyamide and polycarbonate; and special engineering plastics such as polyphenylene sulfide, polyether ketone ketone, polyether ether ketone, and polyetherimide.

[0028] Furthermore, the molding method for the plastic gas cylinder liner in step four is injection molding, blow molding, or rotational molding.

[0029] Furthermore, the heating temperature in step five is 200–290°C, preferably 230–260°C; the heating time is 3–60 min, preferably 5–50 min.

[0030] Another object of the present invention is to provide a thermoplastic polyimide composite winding layer type IV gas cylinder prepared by the method described above.

[0031] Based on the above technical solutions and the technical problems solved, please analyze the advantages and positive effects of the technical solution to be protected by this invention from the following aspects:

[0032] First, addressing the technical problems existing in the prior art and the difficulty of solving them, this paper closely analyzes, in conjunction with the technical solution to be protected by this invention and the results and data obtained during the research and development process, how the technical solution of this invention solves the technical problems, and the inventive technical effects brought about by solving these problems. The specific description is as follows:

[0033] Traditional thermoplastic composite winding processes require the pre-preparation of thermoplastic prepreg tape. However, the prepreg tape is difficult to impregnate, and repeated heating and cooling can lead to resin matrix performance degradation, resulting in insufficient overall structural strength and sealing of the gas cylinder, significantly reducing its reliability and safety. Considering that the basic material type of the winding layer and the material of the plastic liner are difficult to change, improvements must be made to the material synthesis process. To this end, the inventors have creatively solved the problem of poor impregnation of the prepreg tape for Type IV thermoplastic composite gas cylinders by combining low-viscosity polyimide monomers with continuous fibers. This also reduces the number of preparation steps, avoids resin matrix performance degradation caused by repeated heating and cooling, and improves preparation efficiency.

[0034] Second, considering the technical solution as a whole or from a product perspective, the technical effects and advantages of the technical solution to be protected by this invention are specifically described as follows:

[0035] This invention provides a Type IV gas cylinder with a thermoplastic polyimide composite winding layer, which solves the problems of non-recyclability of current thermosetting composite gas cylinders and insufficient wetting of the winding layer and complex process of traditional thermoplastic composite gas cylinders, ensuring that the gas cylinder has sufficient strength and simplifying the manufacturing process.

[0036] This invention addresses the problems of traditional thermosetting composite gas cylinders being non-recyclable, traditional thermoplastic composite winding processes being cumbersome, and difficulties in impregnating prepreg tapes. It adopts a method of impregnating fibers with low-viscosity polyimide monomers, which significantly improves the quality and reliability of gas cylinder products.

[0037] Third, as supplementary evidence of the inventive step of the claims of this invention, it is also reflected in the following important aspects:

[0038] Compared with the prior art, the beneficial effects of the present invention are mainly reflected in the following aspects:

[0039] (1) The present invention proposes a method for impregnating fibers with polyimide monomers, which can effectively improve the degree of fiber impregnation and effectively improve the strength and reliability of the entire gas cylinder;

[0040] (2) Compared with the original process, the improved process of the present invention reduces the complexity of the process, reduces the degree of resin performance degradation, and improves the preparation efficiency.

[0041] (3) The inner liner of the gas cylinder and the resin matrix of the winding layer are both made of thermoplastic resin, which can be recycled and reused, and meets the requirements of national environmental protection policies.

[0042] (4) The inner liner of the gas cylinder is made of plastic, which is lighter than metal liner. The plastic liner is not affected by chemical gas corrosion and the working pressure can reach 35MPa. Attached Figure Description

[0043] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a flowchart of the method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer according to an embodiment of the present invention;

[0045] Figure 2 This is a schematic diagram illustrating the preparation of a Type IV gas cylinder with a thermoplastic composite winding layer provided in an embodiment of the present invention;

[0046] Figure 3 This is a schematic diagram of the thermoplastic composite material wound layer type IV gas cylinder structure provided in an embodiment of the present invention;

[0047] In the diagram: 1. Fiber bundle; 2. Polyimide monomer solution; 3. Gas cylinder liner; 4. Fiber winding layer. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0049] To address the problems existing in the prior art, the present invention provides a method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer. The present invention will be described in detail below with reference to the accompanying drawings.

[0050] I. Explanatory and Illustrative Embodiments. To enable those skilled in the art to fully understand how the present invention is specifically implemented, this section provides an explanatory and illustrative description of the embodiments described in the claims.

[0051] like Figure 1 As shown, the method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer provided in this embodiment of the invention includes the following steps:

[0052] S101, Prepare a monomer resin solution mixture for preparing thermoplastic polyimide;

[0053] S102, a continuous fiber bundle transversely penetrates an impregnation tank containing a mixture of monomer resin solutions to form a monomer solution impregnated material;

[0054] S103 involves heating the monomer solution impregnated material at a certain temperature to remove residual organic solvents and then performing in-situ amidation polymerization to form a polyamic acid prepreg.

[0055] S104, using a variety of winding angle combinations, polyamic acid prepreg is wound onto the surface of the inner liner of a type IV plastic gas cylinder that is filled with gas, to obtain a winding structure;

[0056] S105, the temperature of the winding structure is increased, and the amyl acid in the polyamic acid prepreg undergoes an imidization reaction to produce thermoplastic polyimide;

[0057] S106, the airtightness of the thermoplastic polyimide structure was tested to obtain the Type IV gas cylinder with thermoplastic polyimide composite winding layer.

[0058] The polyimide monomer resin solution mixture in step S101 provided in this embodiment of the invention includes dianhydride monomer and diamine monomer.

[0059] The dianhydride monomer of the polyimide monomer can be one or a mixture of two or more of the following dianhydride monomers: pyromellitic dianhydride, biphenyl dianhydride (including isomers), 4,4'-oxophthalic anhydride (including isomers), triphenyl diether tetracarboxylic anhydride (including isomers), benzophenone dianhydride, 2,2'-bis[4-(3,4-carboxyphenoxy)benzene]propane dianhydride, 4,4'-(hexafluoroisopropyl)diphthalic anhydride, cyclobutane dianhydride, cyclohexane dianhydride, and dicyclopentadiene dianhydride.

[0060] The dianhydride monomer of the polyimide monomer can be one or a mixture of two or more of the following diamine monomers: p-phenylenediamine, m-phenylenediamine, mesitylene-m-phenylenediamine, 2,2'-dimethylbenzidine, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 2,2'-bis(trifluoromethylbenzidine), 4,4'-diaminodiphenylmethane, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, etc. Phenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,4-bis(2-trifluoromethyl-4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 4,4'-bis(3-aminophenoxy)diphenyl sulfone, 9,9-bis(4-aminophenyl)fluorene, 9,9-bis[4-(aminophenoxy)phenyl]fluorene.

[0061] The continuous fiber bundle in step S102 of the present invention is selected from one or more of continuous glass fiber, aramid fiber, basalt fiber, PBO fiber, carbon fiber, natural fiber and ultra-high molecular weight polyethylene fiber.

[0062] In step S103 of this embodiment of the invention, the heating temperature is 100-150°C, preferably 110-140°C; and the heating time is 3-60 min, preferably 5-50 min.

[0063] The winding angle combination in step S104 provided in this embodiment of the invention includes one or more combinations of helical winding, circumferential winding and longitudinal winding.

[0064] The plastic cylinder liner material in step S104 of this embodiment includes general-purpose plastics such as polypropylene (PP), polyethylene (PE), polystyrene (PS), and polyvinyl chloride (PVC); engineering plastics such as polyamide (PA) and polycarbonate (PC); and special engineering plastics such as polyphenylene sulfide (PPS), polyether ketone ketone (PEKK), polyether ether ketone (PEEK), and polyether imide (PEI).

[0065] The plastic gas cylinder liner forming method in step S104 of the present invention is injection molding, blow molding or rotational molding.

[0066] In step S105 of this embodiment of the invention, the heating temperature is 200-290°C, preferably 230-260°C; and the heating time is 3-60 min, preferably 5-50 min.

[0067] II. Application Examples. To demonstrate the inventiveness and technical value of the technical solution of this invention, this section provides application examples of the technical solution of the claims on specific products or related technologies.

[0068] As a preferred embodiment, such as Figure 2 As shown, the preparation method of the thermoplastic polyimide composite winding layer type IV gas cylinder provided in this embodiment of the invention specifically includes the following steps:

[0069] Step 1: Add 20 mol (8046.2 g) of 4,4'-terephthalic anhydride with a purity greater than 99.9% to 22380.4 mL of anhydrous ethanol, heat to 78 °C to completely dissolve, cool to room temperature, add 20 mol (4004.8 g) of 4,4'-diaminodiphenyl ether, stir for 20 min to form a monomer resin solution with a monomer concentration of about 35%.

[0070] Step 2: Use a special fiber spreading equipment to spread out the T70012K unidirectional fiber bundle 1, and use monomer resin solution 2 to continuously impregnate the fiber. The pre-impregnation speed is 0.5m / min, and the monomer content of the pre-impregnated material is 38%±2%.

[0071] Step 3: The monomer solution impregnated material is heated and dried at 120°C to remove residual organic solvents, and then in-situ amidation polymerization is performed to form polyamic acid prepreg.

[0072] Step 4: First, install the plastic gas cylinder liner on the tooling of the winding machine, inflate it and apply a certain tension to the gas cylinder liner. Then, after the carbon fiber-polyamic acid prepreg is pre-tensioned to a certain extent, the reinforcing layer 4 is first wound evenly around the outer wall of the liner 3 in a circumferential and spiral winding manner. In order to achieve the goal of lightweighting, the number of winding layers and the angle are optimized in this embodiment.

[0073] Step 5: Place the Type IV gas cylinder wrapped with carbon fiber-polyamic acid prepreg into a continuous curing oven and keep the gas cylinder horizontally rotating. First, raise the temperature to 100℃ to 150℃, then raise it to 230℃ to 160℃ and cure for 0.5h to 2h. After the oven temperature is lowered to below 60℃, remove the gas cylinder from the oven.

[0074] A schematic diagram of the thermoplastic composite spiral wound layer type IV gas cylinder structure provided in this embodiment of the invention is shown below. Figure 3 As shown.

[0075] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer, characterized in that, The method for preparing the thermoplastic polyimide composite winding layer type IV gas cylinder includes: After preparing a monomer resin solution using dianhydride monomer and diamine monomer, the solution is placed in an impregnation tank, and continuous fiber bundles are used to penetrate laterally to ensure thorough fiber wetting. The fiber bundles are heated to induce in-situ amidation polymerization to form a polyamic acid prepreg, which is then wound onto the surface of the inner liner of a Type IV plastic gas cylinder. The wound layer is heated to react and generate a fiber-reinforced thermoplastic polyimide reinforcing layer, thus obtaining a Type IV gas cylinder, which is then subjected to airtightness testing. The method for preparing the thermoplastic polyimide composite winding layer type IV gas cylinder includes the following steps: Step 1: Prepare a monomer resin solution mixture for the preparation of thermoplastic polyimide; Step 2: A continuous fiber bundle is transversely inserted into an impregnation tank containing the monomer resin solution mixture to form a monomer solution impregnated material. Step 3: The monomer solution impregnating material is subjected to a certain temperature heating treatment to remove the residual organic solvent, and then in-situ amidation polymerization is performed to form polyamic acid prepreg. Step 4: Using a variety of winding angle combinations, the polyamic acid prepreg is wound onto the surface of the inner liner of the inflatable Type IV plastic gas cylinder to obtain a winding structure; Step 5: Increase the temperature of the winding structure, and the amyl acid in the polyamic acid prepreg undergoes an imidization reaction to produce thermoplastic polyimide. Step six: Perform an airtightness test on the thermoplastic polyimide structure to obtain a Type IV gas cylinder with a thermoplastic polyimide composite winding layer. The heating temperature in step three is 110–140°C; the heating time is 5–50 min. The heating temperature in step five is 230–260°C; the heating time is 5–50 minutes.

2. The method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer as described in claim 1, characterized in that, The polyimide monomer resin solution mixture in step one includes dianhydride monomer and diamine monomer; The dianhydride monomer of the polyimide monomer is selected from any one or a mixture of two or more of the following dianhydride monomers: pyromellitic dianhydride, isomer-containing biphenyltetracarboxylic dianhydride, isomer-containing 4,4'-oxydiphthalic anhydride, isomer-containing triphenyl diether tetracarboxylic dianhydride, benzophenone dianhydride, 2,2'-bis[4-(3,4-carboxyphenoxy)benzene]propane dianhydride, 4,4'-(hexafluoroisopropyl)diphthalic anhydride, cyclobutane dianhydride, cyclohexane dianhydride, and dicyclopentadiene dianhydride; The diamine monomer of the polyimide monomer is selected from any one or a mixture of two or more of the following diamine monomers: p-phenylenediamine, m-phenylenediamine, mesitylene-m-phenylenediamine, 2,2'-dimethylbenzidine, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 2,2'-bis(trifluoromethylbenzidine), 4,4'-diaminodiphenylmethane, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, etc. Diphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,4-bis(2-trifluoromethyl-4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 4,4'-bis(3-aminophenoxy)diphenyl sulfone, 9,9-bis(4-aminophenyl)fluorene, 9,9-bis[4-(aminophenoxy)phenyl]fluorene.

3. The method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer as described in claim 1, characterized in that, The continuous fiber bundle in step two is selected from one or more of continuous glass fiber, aramid fiber, basalt fiber, PBO fiber, carbon fiber, natural fiber and ultra-high molecular weight polyethylene fiber.

4. The method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer as described in claim 1, characterized in that, The winding angle combination in step four includes one or more combinations of helical winding, circumferential winding, and longitudinal winding.

5. The method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer as described in claim 1, characterized in that, The plastic cylinder liner material in step four includes general-purpose plastics such as polypropylene, polyethylene, polystyrene, and polyvinyl chloride; engineering plastics such as polyamide and polycarbonate; and special engineering plastics such as polyphenylene sulfide, polyether ketone ketone, polyether ether ketone, and polyetherimide.

6. The method for preparing a Type IV gas cylinder with a thermoplastic polyimide composite winding layer as described in claim 1, characterized in that, The molding method for the plastic gas cylinder liner in step four is injection molding, blow molding, or rotational molding.

7. A thermoplastic polyimide composite wound layer type IV gas cylinder prepared by the method of preparing thermoplastic polyimide composite wound layer as described in any one of claims 1 to 6.

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