A fire-resistant plastic liner full carbon fiber wrapped gas cylinder and preparation method thereof

Abstract

The present application discloses a highly fire-resistant plastic liner fully carbon fiber wrapped gas cylinder and its preparation method, belonging to the technical field of hydrogen storage gas cylinder preparation. The preparation method comprises the following steps: (1) using PA6 as a substrate, obtaining a plastic liner by an injection molding process, and reserving a bottle mouth at the top of the plastic liner; (2) mixing a water-based epoxy resin, a flame retardant additive, ethanol and a curing agent to obtain a slurry, wherein the flame retardant additive is prepared by reacting a diamine monomer and bis(2,3-dibromopropyl) phosphate; (3) impregnating carbon fiber in the slurry to obtain an impregnated fiber, and the impregnated fiber is wound around the outside of the plastic liner, heated and cured to form a fiber winding layer, and a bottle mouth joint is installed at the bottle mouth. The flame retardant additive added to the slurry of the present application can give the gas cylinder a good fire retardant effect, and can form a dense cross-linked network with the epoxy resin, thereby improving the overall fireproof uniformity, sealing and deformation resistance of the gas cylinder and extending the service life.

Description

Technical Field

[0001] The present application relates to a fully carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance and a preparation method thereof, and belongs to the technical field of preparation of hydrogen storage gas cylinders. Background Art

[0002] On-board high-pressure hydrogen storage cylinders are important components of hydrogen fuel cell vehicles. They are the basis for ensuring stable driving of the vehicle. At present, plastic liner full carbon fiber wrapped cylinders are gradually replacing the original high-pressure hydrogen storage containers due to their light weight, large capacity, and high pressure resistance, and are widely used in hydrogen fuel cell vehicles.

[0003] At present, the main research focus is on reducing the generation of cracks and hydrogen leakage in hydrogen storage cylinders, improving the sealing and low-temperature impact resistance of hydrogen storage cylinders, and little attention is paid to the fire prevention function of hydrogen storage cylinders. Since there may be a fire in a car collision, if the fire prevention performance of the hydrogen storage cylinder is poor, it is easy to cause an explosive fire and cause serious casualties. Therefore, it is necessary to develop a hydrogen storage cylinder with high fire resistance.

[0004] Patent CN112303478A records a fire-retardant high-pressure hydrogen storage cylinder, which mainly utilizes carbon fiber impregnated in epoxy resin with flame retardant added. Although this method can have a certain flame retardant effect, the flame retardant is prone to uneven distribution and poor bonding with the epoxy resin, which makes the fireproof effect of the hydrogen storage cylinder poor, and may also affect the sealing and mechanical protection of the fiber winding layer formed by the epoxy resin. Summary of the invention

[0005] In order to solve the above problems, a plastic liner full carbon fiber wrapped gas cylinder with high fire resistance and a preparation method thereof are provided. According to the method, a flame retardant additive prepared by reacting a diamine monomer and bis(2,3-dibromopropyl) phosphate is added to the impregnation slurry. The flame retardant additive not only has a flame retardant function, but also can participate in the curing of the epoxy resin to form a dense cross-linked network with the epoxy resin, thereby improving the overall fire resistance and fire uniformity of the gas cylinder, and can maintain a good fire retardant effect after long-term use.

[0006] According to one aspect of the present application, a method for preparing a fully carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance is provided, comprising the following steps:

[0007] (1) Using PA6 as a base material, a plastic liner is obtained by injection molding, and a bottle mouth is reserved at the top of the plastic liner;

[0008] (2) Mixing 50-60 parts by weight of a waterborne epoxy resin, 5-10 parts of a flame retardant additive, 10-15 parts of ethanol and 2-5 parts of a curing agent to obtain a slurry, wherein the flame retardant additive is prepared by reacting a diamine monomer and bis(2,3-dibromopropyl) phosphate;

[0009] (3) The carbon fiber is impregnated in a slurry to obtain an impregnated fiber, the impregnated fiber is wound around the outside of the plastic liner, heated and cured to form a fiber winding layer, and a bottle mouth joint is installed at the bottle mouth.

[0010] The above slurry uses water-based epoxy resin as the main body and ethanol as a co-solvent to promote the dissolution and dispersion of the flame retardant additive, thereby improving the dispersion uniformity of the slurry, and then improving the reaction uniformity of the flame retardant additive and the water-based epoxy resin in the fiber winding layer to obtain a dense and uniform fiber winding layer.

[0011] Optionally, the reaction conditions of the diamine monomer and bis(2,3-dibromopropyl) phosphate are as follows: placing the diamine monomer and bis(2,3-dibromopropyl) phosphate in a molar ratio of (2-3):1 in a solvent, heating under reflux for 20-24 hours, and obtaining the auxiliary agent after post-treatment.

[0012] Bis(2,3-dibromopropyl)phosphate contains four bromine groups, two bromine groups on each side of the phosphate. The above molar ratio allows the diamine monomer to react with one bromine group on each side of the phosphate. Due to the steric effect, after one of the bromine groups on one side of the phosphate reacts, the other bromine group is difficult to react with the diamine monomer. Therefore, the above molar ratio can ensure that the flame retardant additive contains one bromine group and one diamine monomer on each side of the phosphate. Under this setting, cross-linking of monomers will not occur during the preparation of the flame retardant additive, ensuring the functionality of the flame retardant additive compound. After the above reaction, the diamine monomer and the bromine group can generate a quaternary ammonium salt group, which can give the fiber winding layer antibacterial properties and further improve the flame retardant properties of the flame retardant additive. The other amino group in the diamine monomer that does not generate a quaternary ammonium salt is used to participate in the curing of the epoxy resin.

[0013] Optionally, the diamine monomer is selected from diamine monomers containing an aromatic group.

[0014] The introduction of aromatic groups can reduce the temperature resistance and thermal expansion coefficient of the fiber winding layer, thereby enabling the fiber winding layer to be tightly combined with the plastic liner.

[0015] Preferably, the diamine monomer containing an aromatic group is selected from 2,6-naphthalene diamine and / or 9,10-phenanthrene diamine.

[0016] Optionally, the diamine monomer is selected from diamine monomers containing an aromatic group and an ester group.

[0017] The diamine monomer contains an ester group in addition to an aromatic group. The ester group can improve the compatibility with the epoxy resin, and improve the toughness of the fiber winding layer, reduce its deformation under long-term use of gas filling and degassing, thereby extending the service life of the gas cylinder. At the same time, after the flame retardant prepared from the diamine monomer of this structure reacts with the epoxy resin, it can improve the overall flatness and density of the fiber winding layer, thereby reducing hydrogen leakage.

[0018] Optionally, the preparation steps of the diamine monomer containing an aromatic group and an ester group are as follows:

[0019] S1: p-nitrobenzoic acid reacts with thionyl chloride to obtain p-nitrobenzoyl chloride;

[0020] S2: p-nitrobenzoyl chloride, a monomer containing two hydroxyl groups and triethylamine react to obtain intermediate A;

[0021] S3: Intermediate A is reacted with stannous chloride dihydrate, and then an alkaline solution is added to adjust to weak alkalinity, and a diamine monomer is obtained after treatment.

[0022] Optionally, in step S1, the molar ratio of p-nitrobenzoic acid to thionyl chloride is 1:(2.5-3), the reaction temperature is 60-70° C., and the reaction time is 10-12 h.

[0023] Optionally, in step S2, the molar ratio of p-nitrobenzoyl chloride, the monomer containing two hydroxyl groups and triethylamine is 1:2:2, the reaction temperature is 20-30°C, and the reaction time is 8-10h.

[0024] Optionally, in step S2, the monomer containing two hydroxyl groups is selected from alkyl diols containing 3 to 6 carbon atoms.

[0025] The monomer containing two hydroxyl groups is used to form an ester group with p-nitrobenzoyl chloride, so its structure can affect the performance of the diamine monomer. The present application uses alkyl glycol, which can avoid introducing a large sterically hindered group into the diamine monomer, reduce the steric effect, and thus increase the reactivity of the diamine monomer with bis(2,3-dibromopropyl)phosphate, so as to increase the yield of the flame retardant additive and reduce the production cost of the flame retardant additive. In addition, since the flame retardant additive has the function of acting as an epoxy resin crosslinking point through the amino group, the number of carbon atoms contained in the alkyl glycol will affect the length of the diamine monomer, so the number of carbon atoms in the alkyl glycol is related to the compactness of the epoxy resin crosslinking network. If the number of carbon atoms is too small, the crosslinking points are too dense, the toughness of the fiber winding layer is insufficient, and it is easy to crack during the charging and discharging. If the number of carbon atoms is too large, the density of the fiber winding layer is poor, which increases the hydrogen leakage.

[0026] Optionally, in step S3, the molar ratio of the intermediate A to stannous chloride dihydrate is 1:(1-2), the reaction temperature is 50-70° C., and the reaction time is 15-20 h.

[0027] Optionally, the plastic liner includes 80-100 parts of PA6, 10-20 parts of EVOH, 5-8 parts of polyisocyanate, 2-5 parts of plasticizer, 10-20 parts of epoxy resin, 2-3 parts of curing agent and 1-3 parts of catalyst.

[0028] The plastic liner uses PA6 as the base material, and has good processing performance when compounded with polyisocyanate and EVOH. EVOH itself can improve the plastic liner's resistance to hydrogen permeability, and polyisocyanate can form a cross-linked network, thereby tightly combining with EVOH, thereby improving the density of the plastic liner. It also contains epoxy resin and curing agent. During the injection molding process, the epoxy resin and polyisocyanate can form a cross-linked network respectively, and the cross-linked network can be interspersed inside the plastic liner, thereby improving the mechanical properties and deformation resistance of the plastic liner.

[0029] Optionally, the thickness of the plastic liner is 5-6 mm, the thickness of the fiber winding layer is 30 mm, and the amount of carbon fiber impregnation is 20-30 wt%.

[0030] According to another aspect of the present application, there is provided a method for preparing a plastic liner full carbon fiber wrapped gas cylinder with high fire resistance as described in any of the above items, and a plastic liner full carbon fiber wrapped gas cylinder with high fire resistance obtained by the method.

[0031] The beneficial effects of this application include but are not limited to:

[0032] 1. The highly fireproof plastic liner all-carbon fiber wrapped gas cylinder according to the present application can significantly improve the fireproof and flame retardant effect of the gas cylinder, and the fireproof and flame retardant uniformity at various positions of the gas cylinder is high, thereby achieving long-term and effective protection for the gas cylinder and improving the safety of the gas cylinder.

[0033] 2. According to the highly fire-resistant plastic liner all-carbon fiber wrapped gas cylinder of the present application, the flame retardant additive not only has flame retardant properties, but also can participate in the curing reaction of the epoxy resin, so that the flame retardant additive reacts with the epoxy resin to form a dense cross-linked network, protecting and flame retardant the gas cylinder.

[0034] 3. According to the highly fire-resistant plastic liner all-carbon fiber wrapped gas cylinder of the present application, the bis(2,3-dibromopropyl) phosphate used in the flame retardant additive is obtained by reacting with a diamine monomer, wherein the bis(2,3-dibromopropyl) phosphate contains a phosphate group and a bromine element, which can play a good flame retardant effect, and the amino group contained in the diamine monomer participates in the curing of the epoxy resin and can act as a cross-linking agent, thereby increasing the number of cross-linking points of the epoxy resin network, thereby improving the density of the epoxy resin network and improving the protective effect. DETAILED DESCRIPTION

[0035] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0036] Unless otherwise specified, the raw materials in the examples and comparative examples of the present application were purchased through commercial channels.

[0037] The curing agent in the present application can be any one or more of an alkaline curing agent and an acidic curing agent, and the plasticizer and catalyst can also be selected from existing plasticizers and catalysts in the prior art. The specific types of the above curing agent, plasticizer and catalyst do not constitute a limitation to the present application. In the following examples, diethylenetriamine is used as a curing agent, dibutyl phthalate is used as a plasticizer, and dibutyltin dilaurate is used as a catalyst.

[0038] Unless otherwise specified, the methods used in the examples and comparative examples of the present application are conventional methods in the prior art. The solvents used may be methanol, ethanol, DMF, DMSO, ethyl acetate, chloroform, dichloromethane, acetone, etc. The type of solvent used does not limit the reaction process, so in the following examples, a suitable solvent can be selected according to the properties of the raw materials and actual needs.

[0039] Example 1

[0040] This embodiment relates to a method for preparing a carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance, comprising the following steps:

[0041] (1) Mix 80 parts of PA6, 10 parts of EVOH, 5 parts of polyisocyanate, 10 parts of epoxy resin, 2 parts of curing agent, 2 parts of plasticizer, and 1 part of catalyst, and injection mold them into a plastic liner with a thickness of 5 mm. The top of the plastic liner is reserved for the bottle mouth;

[0042] (2) 60 parts of waterborne epoxy resin, 10 parts of flame retardant additive, 15 parts of ethanol and 5 parts of curing agent are mixed to obtain a slurry, wherein the flame retardant additive is composed of 2,6-naphthalene diamine and bis(2,3-dibromopropyl) phosphate in a molar ratio of 2:1 in a solvent, heated to reflux for 20 hours, rotary evaporated, extracted with a mixed solvent of ether and acetonitrile in a volume ratio of 1:1 for 5 times, and dried to obtain a slurry;

[0043] (3) The carbon fiber is impregnated in the slurry to obtain impregnated fiber, the impregnation amount of the carbon fiber is 30wt%, the impregnated fiber is wound around the outside of the plastic liner, and after heating and curing at 120°C for 4 hours, a fiber winding layer with a thickness of 30mm is formed, and a bottle mouth joint is installed at the bottle mouth.

[0044] Example 2

[0045] This embodiment relates to a method for preparing a carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance, comprising the following steps:

[0046] (1) 100 parts of PA6, 20 parts of epoxy resin, 20 parts of EVOH, 8 parts of polyisocyanate, 3 parts of curing agent, 5 parts of plasticizer and 3 parts of catalyst were mixed and injection molded into a plastic liner with a thickness of 6 mm. A bottle mouth was reserved at the top of the plastic liner.

[0047] (2) 50 parts of waterborne epoxy resin, 5 parts of flame retardant additive, 10 parts of ethanol and 2 parts of curing agent are mixed to obtain a slurry, wherein the flame retardant additive is composed of 9,10-phenanthrene diamine and bis(2,3-dibromopropyl) phosphate in a molar ratio of 3:1 in a solvent, heated to reflux for 24 hours, rotary evaporated, extracted with a mixed solvent of ether and acetonitrile in a volume ratio of 1:1 for 5 times, and dried to obtain a slurry;

[0048] (3) The carbon fiber is impregnated in the slurry to obtain impregnated fiber, the impregnation amount of the carbon fiber is 20wt%, the impregnated fiber is wound around the outside of the plastic liner, and after heating and curing at 120°C for 4 hours, a fiber winding layer with a thickness of 30mm is formed, and a bottle mouth joint is installed at the bottle mouth.

[0049] Example 3

[0050] This embodiment relates to a method for preparing a carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance, comprising the following steps:

[0051] (1) Same as Example 2;

[0052] (2) 55 parts of waterborne epoxy resin, 8 parts of flame retardant additive, 12 parts of ethanol and 2 parts of curing agent are mixed to obtain a slurry, wherein the flame retardant additive is composed of p-phenylenediamine and bis(2,3-dibromopropyl) phosphate in a molar ratio of 2.5:1 in a solvent, heated to reflux for 24 hours, rotary evaporated, extracted with a mixed solvent of ether and acetonitrile in a volume ratio of 1:1 for 5 times, and dried to obtain;

[0053] (3) Same as Example 2.

[0054] Example 4

[0055] The difference between this embodiment and embodiment 3 is that a diamine monomer containing an aromatic group and an ester group is used to replace p-phenylenediamine. The preparation steps of the diamine monomer containing an aromatic group and an ester group are as follows:

[0056] S1: adding p-nitrobenzoic acid and thionyl chloride in a molar ratio of 1:2.5 to a solvent, reacting at 70°C for 10 h, and removing excess thionyl chloride under reduced pressure to obtain p-nitrobenzoyl chloride;

[0057] S2: dissolving p-nitrobenzoyl chloride in a solvent to obtain solution A, dissolving 1,3-propylene glycol and triethylamine in a solvent to obtain solution B, wherein the molar ratio of p-nitrobenzoyl chloride, 1,3-propylene glycol and triethylamine is 1:2:2, and adding solution B dropwise to solution A at room temperature, and then reacting at 30°C for 8h, filtering, washing and drying to obtain intermediate A;

[0058] S3: Add intermediate A and stannous chloride dihydrate in a molar ratio of 1:2 to a solvent, react at 50°C for 20 hours, then add 5% sodium bicarbonate solution to adjust the solution to alkalinity, filter, separate, rotary evaporate, and dry to obtain a diamine monomer.

[0059] Example 5

[0060] The difference between this embodiment and embodiment 3 is that a diamine monomer containing an aromatic group and an ester group is used to replace p-phenylenediamine. The preparation steps of the diamine monomer containing an aromatic group and an ester group are as follows:

[0061] S1: adding p-nitrobenzoic acid and thionyl chloride in a molar ratio of 1:3 to a solvent, reacting at 60°C for 12 hours, and removing excess thionyl chloride under reduced pressure to obtain p-nitrobenzoyl chloride;

[0062] S2: dissolving p-nitrobenzoyl chloride in a solvent to obtain solution A, dissolving 1,6-hexanediol and triethylamine in a solvent to obtain solution B, wherein the molar ratio of p-nitrobenzoyl chloride, 1,6-hexanediol and triethylamine is 1:2:2, and adding solution B dropwise to solution A at room temperature, and then reacting at 20°C for 10 hours, filtering, washing and drying to obtain intermediate A;

[0063] S3: Add intermediate A and stannous chloride dihydrate in a molar ratio of 1:1 to a solvent, react at 70°C for 15 hours, then add 5% sodium bicarbonate solution to adjust the solution to alkalinity, filter, separate, rotary evaporate, and dry to obtain a diamine monomer.

[0064] Example 6

[0065] The difference between this embodiment and embodiment 5 is that 1,8-octanediol is used to replace 1,6-hexanediol, and the rest is the same as embodiment 5.

[0066] Example 7

[0067] The difference between this embodiment and embodiment 5 is that hydroquinone is used to replace 1,6-hexanediol, and the rest is the same as embodiment 5.

[0068] Comparative Example 1

[0069] The difference between this comparative example and Example 1 is that tris(2,3-dibromopropyl) phosphate is used in the slurry to replace the flame retardant additive prepared by reacting 2,6-naphthalenediamine and bis(2,3-dibromopropyl) phosphate, and the rest is the same as Example 1.

[0070] Comparative Example 2

[0071] The difference between this comparative example and Example 1 is that bis(2,3-dibromopropyl)phosphate is directly used as a flame retardant auxiliary agent, and the rest is the same as Example 1.

[0072] Test Example 1

[0073] The hydrogen permeability coefficient of the hydrogen storage cylinders prepared in the above embodiments and comparative examples was tested with reference to GB / T42610-2023; the minimum bursting pressure, anti-aging performance, and weather resistance performance of the hydrogen storage cylinders were tested with reference to GB / T42612-2023; wherein, the anti-aging performance was evaluated using the number of 2-87.5MPa water pressure cycle fatigue failures A; the weather resistance was evaluated using the number of 2-56MPa pressure cycle fatigue failures B at -40°C and the number of 2-87.5MPa cycle pressure cycle fatigue failures C at 270°C. In the peel strength test, the gas cylinder is cut into strips with a width of 150mm×200mm, and the plastic liner and the fiber winding layer are pre-peeled off 50mm along the length direction. The sample is placed in an environment with a temperature of 23±2℃ and a relative humidity of 50±5% for 4 days. The two ends of the peeled part of the sample are clamped on the upper and lower clamps of the tensile testing machine respectively, so that the peeled part of the sample is in a vertical state and the unpeeled part is in a horizontal state. The testing machine is turned on for peeling, and the test speed is set to 100mm / min. The peel strength is calculated.

[0074] The specific test results are shown in Table 1 below:

[0075] Table 1

[0076]

[0077] Test Example 2

[0078] The highly fire-resistant plastic liner all-carbon fiber wrapped gas cylinders prepared in the above embodiments and comparative examples were cut into 10×10 cm samples and subjected to a fire resistance test. The samples were exposed to the flame of an oil pan for 60 seconds to observe whether the samples burned. If there was a flame in the gas cylinder, the extinguishing time of the flame was observed after the fire source was removed. The test results are shown in Table 2.

[0079] Table 2

[0080]

[0081] The corrosion resistance and aging resistance tests were carried out on the highly fire-resistant plastic liner all-carbon fiber wrapped gas cylinders prepared in the above embodiments and comparative examples. The above gas cylinders can meet the corrosion resistance and aging resistance requirements of hydrogen cylinders in the industry.

[0082] The above is only the embodiment of the present application, and the protection scope of the present application is not limited by these specific embodiments, but is determined by the claims of the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the technical ideas and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for preparing a fully carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance, characterized in that: The steps include: (1) Using PA6 as a substrate, a plastic liner is obtained by injection molding, wherein a bottle mouth is reserved at the top of the plastic liner, and the plastic liner comprises 80-100 parts of PA6, 10-20 parts of EVOH, 5-8 parts of polyisocyanate, 2-5 parts of plasticizer, 10-20 parts of epoxy resin, 2-3 parts of curing agent and 1-3 parts of catalyst; (2) Mixing 50-60 parts by weight of a waterborne epoxy resin, 5-10 parts of a flame retardant additive, 10-15 parts of ethanol and 2-5 parts of a curing agent to obtain a slurry, wherein the flame retardant additive is prepared by reacting a diamine monomer and bis(2,3-dibromopropyl) phosphate; (3) impregnating carbon fiber into slurry to obtain impregnated fiber, winding the impregnated fiber to the outside of the plastic liner, heating and curing to form a fiber winding layer, and installing a bottle mouth joint at the bottle mouth; The reaction conditions of the diamine monomer and bis(2,3-dibromopropyl) phosphate are as follows: placing the diamine monomer and bis(2,3-dibromopropyl) phosphate in a molar ratio of (2-3):1 in a solvent, heating under reflux for 20-24 hours, and obtaining the auxiliary agent after post-treatment; The diamine monomer is selected from diamine monomers containing an aromatic group.

2. The method for preparing a fully carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance according to claim 1, characterized in that: The diamine monomer is selected from diamine monomers containing an aromatic group and an ester group.

3. The method for preparing a fully carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance according to claim 2, characterized in that: The preparation steps of the diamine monomer containing an aromatic group and an ester group are as follows: S1: p-nitrobenzoic acid reacts with thionyl chloride to obtain p-nitrobenzoyl chloride; S2: p-nitrobenzoyl chloride, a monomer containing two hydroxyl groups and triethylamine react to obtain an intermediate A, wherein the monomer containing two hydroxyl groups is selected from an alkyl diol containing 3 to 6 carbon atoms; S3: Intermediate A is reacted with stannous chloride dihydrate, and then an alkaline solution is added to adjust to weak alkalinity, and a diamine monomer is obtained after treatment.

4. The method for preparing a fully carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance according to claim 3, characterized in that: In step S1, the molar ratio of p-nitrobenzoic acid to thionyl chloride is 1:(2.5-3), the reaction temperature is 60-70°C, and the reaction time is 10-12h.

5. The method for preparing a fully carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance according to claim 3, characterized in that: In step S2, the molar ratio of p-nitrobenzoyl chloride, the monomer containing two hydroxyl groups and triethylamine is 1:2:2, the reaction temperature is 20-30°C, and the reaction time is 8-10h.

6. The method for preparing a fully carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance according to claim 3, characterized in that: In step S3, the molar ratio of the intermediate A to stannous chloride dihydrate is 1:(1-2), the reaction temperature is 50-70° C., and the reaction time is 15-20 h.

7. A highly fire-resistant plastic liner fully carbon fiber wrapped gas cylinder, characterized in that: The gas cylinder is prepared by the method for preparing a fully carbon fiber wrapped gas cylinder with a plastic liner having high fire resistance as described in any one of claims 1 to 6.

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