QUICK-COOKING COMPOSITION FOR THE MANUFACTURE OF SEMI-FINISHED PRODUCTS ALLOWING THE MANUFACTURE OF TYPE IV COMPOSITE PRESSURE TANKS FOR THE ON-BOARD STORAGE OF HYDROGEN GAS.

Abstract

The invention relates to a composition (C) comprising (A) 70 to 95 parts by mass of an epoxy resin with a viscosity of between 1 and 150 kPa.s at a temperature of between 20°C and 25°C, and (B) 5 to 30 parts by mass of a hardener dispersed in the resin, per 100 parts by mass of resin present in the composition, the hardener being an ionic liquid containing a phosphonium cation. The invention also relates to a semi-finished product or towpreg, comprising - a bundle of fibers (F) chosen from carbon fibers, glass fibers, aramid fibers, silicon carbide fibers, organic fibers and - a composition (C), said bundle of fibers being impregnated with said composition, and the volume ratio of (F) is between 40 and 70% and that of (C) is between 30 and 60%.Another subject of the invention is the use of a composition (C) or a semi-finished product according to the invention, for the manufacture of a hydrogen tank, in particular a pressure tank, type IV, made of composite material, for the on-board storage of gaseous hydrogen. Figure for the abstract: None.

Description

Title of the invention: FAST-COOKING COMPOSITION FOR THE MANUFACTURE OF SEMI-FINISHED PRODUCTS ALLOWING THE MANUFACTURE OF TYPE IV COMPOSITE PRESSURE TANKS FOR THE ON-BOARD STORAGE OF HYDROGEN GAS. Technical field of the invention

[0001] The present invention relates to the field of manufacturing type IV pressure tanks, made of composite material, for the storage of gaseous hydrogen, for both fixed and mobile applications, such as, for example, hydrogen storage infrastructures, the transport of hydrogen for refueling, hydrogen rail vehicles, buses, trucks, airplanes, boats and other hydrogen vehicles, and hydrogen cars. Technical background

[0002] Today, on-board storage systems for hydrogen gas in pressurized tanks for transportation applications exist but only a few manufacturers market a few thousand approved tanks per year. With the emergence of the market related to low-carbon mobility, pressurized storage, there is no supply chain (transformation of raw materials and components into a finished product that is delivered to the end customer) ready for mass production (millions of units per year) at a moderate cost. For example, the compact, reliable, safe and economical storage of hydrogen gas under 700 bar is a major challenge for the widespread commercialization of fuel cell electric vehicles (FCEV) and other fuel cell applications.While some lightweight FECVs with a range of more than 500 km have been introduced since 2015, affordable on-board hydrogen storage still remains a major obstacle and the quantity of manufactured tanks remains low. Much of the effort in hydrogen storage programs is focused on developing cost-effective hydrogen storage technologies with improved energy density (gravimetric capacity close to 6%, i.e. 6% of the mass of the storage system is hydrogen).

[0003] Hydrogen tanks for automotive applications, buses, trucks, trains, airplanes, boats, are already available but they do not yet meet all the expectations of manufacturers in the perspective of mass production of systems operating on hydrogen. This is true with regard to the manufacture of H2 tanks but also for the deployment and use of fuel cell means of transport.

[0004] Even though the manufacturing cost of Type IV pressure tanks made of composite material for on-board storage of gaseous hydrogen only represents about 10% to 30% of the cost of the storage system, mass production capacity is a major challenge for automotive integrators. The polymerization (or hardening) step of the composite material matrix ensuring resistance to high pressure is the main step that currently limits the manufacturing speed of the tank. The matrix of the composite material of composite pressure tanks is generally an epoxy matrix.

[0005] In order to be able to produce several million vehicles per year, the polymerization (or hardening) time of the composite matrices for type IV tanks must be considerably reduced.

[0006] Today, with epoxy matrices, the duration of the polymerization (or curing) process for a 700 bar pressure vessel is approximately 12 to 16 hours, which is too long for mass production such as that required for the automotive industry.

[0007] There is therefore a real need to make the manufacture of type IV pressure tanks in composite material for the on-board storage of gaseous hydrogen efficient for mass production and industrially interesting.

[0008] In particular, there is a real need to significantly reduce the duration of the polymerization (or hardening) step of the matrix of the composite material in order to minimize the manufacturing cycle time of a tank.

[0009] To achieve this, the present invention proposes a new composition for the composite material which takes into account the technical and regulatory constraints linked to high-pressure composite tanks for the storage of on-board hydrogen. Summary of the invention

[0010] The present invention relates to a composition (C) comprising

[0011] (A) 70 to 95 parts by mass of an epoxy resin with a viscosity of between 1 Pa.s and 150 kPa.s at a temperature between 20°C and 25°C, and

[0012] (B) 5 to 30 parts by mass of a hardener dispersed in the resin,

[0013] per 100 parts by mass of resin present in the composition,

[0014] characterized in that the hardener is an ionic liquid containing a phosphonium cation of formula P(RiR2R3R4)+ in which RB R2, R3 and R4, identical or different, represent a hydrogen atom, an alkyl radical having 1 to 18 carbon atoms, an aryl radical having 6 to 20 carbon atoms, said alkyl and aryl radicals being optionally substituted.

[0015] The type IV high-pressure tank, made of composite material, consists of an internal shell made of polymer material, called a bladder or liner in English, most often thermoplastic, with metal connectors, called bases or bosses in English, at one or both ends. The bases ensure the connection of the tank with the storage system. The liner ensures the hydrogen seal. This assembly is covered with a structuring composite material, ensuring the structuring to the internal pressure, usually comprising a thermosetting matrix, most often an epoxy resin, and a reinforcement most often based on long fibers, for example, carbon or glass.

[0016] The present invention therefore aims to support the development of on-board storage systems for gaseous hydrogen (CGH2 compressed gaseous hydrogen in English, CPV Composite Pressure Vessel) in pressure tanks which are improved, in order to anticipate the future massive deployment of the aforementioned technologies, in particular by focusing on the composition of the composite material of the tank, and more precisely on the resin and its polymerization reaction which strongly impacts the manufacturing rates over durations greater than 10 hours in general.

[0017] The composition of the invention is particularly advantageous because it has rapid polymerization (or hardening) in comparison with the compositions based on epoxy matrices used today, and this in particular thanks to the use of phosphorus-containing ionic liquids as hardener. Indeed, the polymerization (or hardening) time of the epoxy matrix in a composition according to the invention is less than 12 hours, less than 10 hours, in particular less than 8 hours, and more particularly less than 6 hours.

[0018] Another object of the invention is a semi-product called a semi-finished product or towpreg in English, characterized in that it comprises

[0019] - a bundle of fibers (F) chosen from carbon, glass, aramid, silicon carbide, organic fibers and

[0020] - a composition (C) according to the invention,

[0021] said bundle of fibers being impregnated with said composition, and

[0022] the volume rate of (F) is between 40 and 70% and that of (C) is between 30 and 60%.

[0023] The fiber bundle may be in the form of a non-woven loose fiber web or aggregate, or in woven form.

[0024] The semi-finished product or towpreg can be polymerized after impregnation of the fibers (F) with the composition (C).

[0025] The semi-finished product or towpreg may, optionally, be wound around a reel after impregnation of the fibers (F) with the composition (C) and polymerization (or hardening) thereof.

[0026] Composition (C) and the semi-finished product or tow preg according to the invention can be used for the manufacture of type IV pressure tanks, made of composite material, for the on-board storage of gaseous hydrogen, in particular for both fixed and mobile applications, such as, for example, hydrogen storage infrastructures, the transport of hydrogen for refueling, hydrogen rail vehicles, buses, trucks, airplanes, boats and other hydrogen vehicles, and hydrogen cars.

[0027] The invention also relates to the use of a composition (C) or a semi-finished product, according to the invention, for the manufacture of a hydrogen tank, in particular a pressure tank, of type IV, made of composite material, for the on-board storage of gaseous hydrogen.

[0028] Another object of the invention is a structure, made of composite material, comprising a polymerized semi-finished product or towpreg.

[0029] More particularly, the structure is a pressure tank.

[0030] Preferably, the tank is a type IV pressure tank for the on-board storage of gaseous hydrogen. Detailed description of the invention

[0031] The present invention relates to a composition (C) characterized in that it comprises

[0032] (A) 70 to 95 parts by mass of an epoxy resin with a viscosity of between 1 Pa.s and 150 kPa.s at a temperature between 20°C and 25°C, and

[0033] (B) 5 to 30 parts by mass of a hardener dispersed in the resin,

[0034] per 100 parts by mass of resin present in the composition,

[0035] characterized in that the hardener is an ionic liquid containing a phosphonium cation of formula P(RiR2R3R4)+ in which Rb R2, R3 and R4, identical or different, represent a hydrogen atom, an alkyl radical having 1 to 18 carbon atoms, an aryl radical having 6 to 20 carbon atoms, said alkyl and aryl radicals being optionally substituted.

[0036] For the purposes of the present invention, the term "alkyl" means a linear, branched or cyclic, saturated, optionally substituted carbon radical comprising 1 to 18 carbon atoms, for example 1 to 12 carbon atoms, for example 1 to 6 carbon atoms. As saturated, linear or branched alkyl, mention may be made, for example, of methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, nonyl, decyl, undecyl, dodecanyl radicals and their branched isomers. As cyclic alkyl, mention may be made of cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, bicylco[2,1,1]hexyl, bicyclo[2,2,1]heptyl radicals.

[0037] The term "aryl" denotes a mono- or polycyclic aromatic substituent comprising 6 to 20 carbon atoms, for example, 6 to 10 carbon atoms. For information purposes, phenyl, benzyl, naphthyl, phenanthrenyl groups may be mentioned.

[0038] The alkyl and aryl radicals may be optionally substituted by one or more hydroxyl groups (-OH), one or more alkoxy groups (-O-alkyl); one or more aryloxy groups (-O-aryl); one or more halogen atoms chosen from fluorine, chlorine, bromine and iodine atoms; with alkyl and aryl as defined in the context of the present invention.

[0039] In one embodiment, in the phosphonium cation, R2, R3 and R4, identical or different, represent

[0040] a hydrogen atom,

[0041] an alkyl radical chosen from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and their branched isomers,

[0042] an aryl radical chosen from phenyl, benzyl,

[0043] said alkyl and aryl radicals being optionally substituted.

[0044] The phosphonium cation can be chosen from PH4+, P(CH3)4+, P(Ph)4+, P(CH3)(Ph)3+, P(CH2OH)4+.

[0045] According to one embodiment of the invention, in the composition, the ionic liquid contains a dicyanamide anion (C2N3).

[0046] In this embodiment, the composition (C) comprises 10 to 30 parts by mass of ionic liquid, per 100 parts by mass of epoxy resin present in the composition.

[0047] In all variants and embodiments of the invention, composition (C) can be polymerized under the action of temperature depending on the desired application and the desired characteristics. Those skilled in the art will know how to choose and adapt these conditions.

[0048] According to another embodiment of the invention, the composition comprises an ionic liquid which contains a phosphinate anion of formula (PO2R5R6) in which R5 and R6, identical or different, represent a hydrogen atom, an alkyl radical having 1 to 18 carbon atoms, an aryl radical having 6 to 20 carbon atoms, said alkyl and aryl radicals being optionally substituted.

[0049] In this other embodiment, in the phosphinate anion, R5 and R6, identical or different, represent

[0050] a hydrogen atom,

[0051] an alkyl radical chosen from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and their branched isomers,

[0052] an aryl radical chosen from phenyl, benzyl,

[0053] said alkyl and aryl radicals being optionally substituted.

[0054] The phosphinate anion can be chosen from (PO2H2), (PO2(CH3)2), (PO2(C7H30)2), (PO2Ph2).

[0055] In this other embodiment, when the ionic liquid contains a phosphinate anion as described above, the composition comprises 5 to 20 parts by mass of ionic liquid, per 100 parts by mass of epoxy resin present in the composition.

[0056] The epoxy resin (A) present in the composition may be, for example, of bisphenol type, such as bisphenol A, bisphenol B, bisphenol F, bisphenol S, ortho-, meta-, para-cresol novolac.

[0057] The epoxy resin (A) has a viscosity of between 1 Pa.s and 150 kPa.s at a temperature of between 20°C and 25°C. The epoxy resin (A) may be, for example, a resin with a viscosity of 16.9 kPa.s (+ / - 20%) at 25°C and 113.0 kPa.s at 20°C.

[0058] The viscosity is measured at a temperature between 20°C and 25°C, using an ARES Rheometer device, from TA® instruments Brookfield LV DV 1+ from BROOKFIELD ENGINEERING LABORATORIES, INC. The ARES rheometer uses a plane / plane geometry with 25 mm (upper geometry) and 40 mm (lower geometry) aluminum discs. The composition is hot-deposited (60°C) on the geometries and then cooled to a temperature between 20°C and 25°C to perform the viscosity measurement. The “DFS” Dynamic Frequency Sweep (strain controlled) 1-100 rad / s test is performed with a deformation of approximately 1%. The viscosity measurement is recorded for a frequency of 1 rad / s.

[0059] The composition according to the invention can be prepared by mixing the components (A) and (B) as indicated in the examples. In particular, the process consists in mixing an epoxy resin (A) and an ionic liquid (B) as defined above, until a homogeneous composition is obtained, at a temperature which prevents the initiation of the polymerization of (A).

[0060] The composition can be prepared in a simple (glass) reactor equipped with a stirring blade and under air. The temperature can be controlled by a heating plate and a silicone oil bath.

[0061] Continuous mixing is a process of continuously dosing ingredients directly into the mixing zone and, consequently, generating a continuous flow of mixed product at the outlet of the mixer. This principle guarantees perfect control of the meeting point of the ingredients and therefore a unique distribution quality for the mixed product. The product obtained is therefore in the form of a homogeneous mixture. All continuous mixer known to those skilled in the art may be suitable for the manufacture of the composition.

[0062] Without wishing to be bound by theory, the inventors have found that the use of ionic liquids as hardeners in a composition according to the invention allows crosslinking via a catalytic mechanism and not an addition mechanism. In addition to reduced curing times, ionic liquids make it possible to reduce the amount of polymerization (or hardening) agent necessary for complete crosslinking of the epoxy matrix (i.e. 20-50 parts per 100 parts of resin or phr, for standard amine systems). Indeed, the ionic liquid, under the effect of temperature, will allow the opening of the oxirane ring by the nucleophilic attack of the anion on the a carbon of this function.

[0063] This so-called activation reaction leads to the formation of alcoholate, a reactive function with respect to the other epoxide units. A second step called propagation consists of the homopolymerization of the alcoholate units formed on the oxirane rings.

[0064] Under suitable temperature conditions, this reaction continues until complete crosslinking of the epoxy matrix (conversion > 95%).

[0065] Another object of the invention is a semi-product also called a semi-finished product or towpreg in English, characterized in that it comprises

[0066] - a bundle of fibers (F) chosen from carbon, glass, aramid, silicon carbide, organic fibers and

[0067] - a composition (C) according to the invention,

[0068] said bundle of fibers being impregnated with said composition, and

[0069] the volume rate of (F) is between 40 and 70% and that of (C) is between 30 and 60%.

[0070] The terms “semi-finished product” and “semi-finished product” and “towpreg” are interchangeable and can be used interchangeably to designate the same product.

[0071] By organic fibers we mean fibers based on carbon and hydrogen. They can be natural (cellulose, silk, linen), derived from cellulose (cellulose acetate, etc.), synthetic (polyester, polyethylene, etc.).

[0072] The fiber bundle may be in the form of a non-woven loose fiber web or aggregate, or in woven form.

[0073] The reinforcing fiber bundle preferably comprises 1000 to 70000 filaments having a diameter of 3 to 100 μm.

[0074] Preferably, the fibers (D) are carbon fibers. In this respect, mention may be made of TORAYCA T720 carbon fibers from the company Toray®.

[0075] The semi-finished product, also called a semi-finished product or towpreg in English, as its name indicates, is an intermediate product, intended to be used for the manufacturing of composite material structures, such as type IV pressure tanks made of composite material, particularly after hot molding.

[0076] The semi-finished product or towpreg may be manufactured by a continuous production process comprising the steps of

[0077] (i) heating a composition (C) comprising the resin (A) and the ionic liquid (B) at a temperature between 40 and 60°C, and

[0078] (ii) continuous impregnation of the moving fiber bundle (F) with the composition (C).

[0079] Thus, continuous production is carried out without interruption, by a continuous flow of composition and fibers (F), and is concentrated in a single location. The final product, here the semi-finished product or towpreg, is discharged without interruption of the process.

[0080] The continuous impregnation of the fiber bundle (F) by the composition (C) takes place at a temperature which can range from 20°C to 80°C.

[0081] The duration of this impregnation can range from a few seconds to a few minutes, for example, 10 seconds to 5 minutes.

[0082] After step (ii), the impregnated fibers are cooled to a temperature below 30°C.

[0083] In step (ii), the impregnation of the fiber bundle (F) with the composition (C) can be done in several ways, by methods well known to those skilled in the art, including by spraying, by immersion or by transfer.

[0084] Once manufactured, the semi-finished product or towpreg can be stored as is. The semi-finished product can also be wound, for example around a reel.

[0085] The semi-finished product can be used for filament winding on a polymer bladder or liner, in particular a polyethylene or polyamide bladder or liner.

[0086] The bladder (or liner) may be that of a tank, for example a hydrogen tank, in particular a type IV pressurized tank made of composite material, for the on-board storage of gaseous hydrogen.

[0087] The invention also relates to the use of a composition (C) according to the invention, or of a semi-finished product or towpreg according to the invention, for the manufacture of a hydrogen tank, in particular a type IV pressurized tank made of composite material, for the on-board storage of gaseous hydrogen, in particular for both fixed and mobile applications, such as, for example, hydrogen storage infrastructures, the transport of hydrogen for refueling, hydrogen rail vehicles, buses, trucks, airplanes, boats and other hydrogen vehicles, and hydrogen cars.

[0088] Another object of the invention is a structure, made of composite material, comprising a polymerized semi-finished product or towpreg.

[0089] The polymerization can be carried out by polymerization methods known to those skilled in the art, for example under the action of temperature.

[0090] More particularly, the structure is a pressure tank.

[0091] Preferably, the tank is a type IV pressure tank for the on-board storage of gaseous hydrogen.

[0092] According to one embodiment, the polymerized towpreg is wound on a polymer bladder or liner, in particular a polyethylene bladder or liner.

[0093] According to another embodiment, the polymerized towpreg is wound on a polymer bladder or liner, in particular a polyamide bladder or liner.

[0094] Preferably, the tank is a type IV pressure tank for the on-board storage of gaseous hydrogen.

[0095] The composition (C) according to the invention has a rapid curing (only a few hours) during the manufacture of type IV pressure composite tanks for the on-board storage of gaseous hydrogen. The rapid curing of the composition is essentially due to the use of the ionic liquid as a hardener.

[0096] The composition of the invention comprises an epoxy resin (A) because this type of thermosetting polymer is most commonly used for the manufacture of pressure tanks for the on-board storage of hydrogen.

[0097] It is adapted to present the characteristics required to allow the manufacture of a semi-finished product called tow-preg in English by the hot-melt method, by impregnation of the carbon fiber bundles / sheets, for example. This semi-finished product or tow-preg, which can be in the form of a coil, is then used to manufacture the tanks. Once deposited around the bladder or liner, most often by filament winding, the epoxy matrix is ​​then polymerized most often in an oven or a tunnel furnace. The tanks thus obtained can be approved according to the criteria of the regulations currently in force (406 2010, R134). EXAMPLES

[0098] Protocol for preparing a composition according to the invention

[0099] SR 1228 resin, marketed by the Sicomin company, and of the hot-melt type, has a viscosity of 113 kPa.s at 20°C. Sicomin SR 1228 resin is semi-solid and non-crystalline at room temperature (20°C -25°C). Consequently, it is necessary to heat it to approximately 50°C for use.

[0100] The resin is introduced into a thermostatically controlled reactor and then the ionic liquid Cyphos® LI 105 (trihexyl(tetradecyl)phosphonium bis-2,4,4-(trimethylpentyl) phosphinate or [R4PA]), marketed by the company Strem Chemicals, is added at a rate of 15 parts by weight or pp or phr in English (15 parts Cyphos® LI 105 per 100 parts of SR 1228 resin). The mixture is stirred for approximately 30 minutes at 60°C.

[0101] Once homogenized, a composition according to the invention is obtained and can be used for impregnating the reinforcing fibers. During this step, the composition is continuously sprayed onto a wick of TORAYCA T720 carbon fiber from the company Toray® at a temperature between 60 and 80°C maximum.

[0102] The wick impregnated with the composition (resin + ionic liquid) can then be wound in the form of a semi-finished product or tow-preg and left to cool as is. Storage must be carried out in a clean, dry area, away from light, up to a temperature of 20°C. Under these conditions, and depending on the ionic liquid used, the invention makes it possible to guarantee a useful life of the semi-finished product or tow-preg of at least two weeks and up to more than four weeks. Cooking cycle

[0103] The cooking cycles proposed for the polymerization of a composition as prepared above are 5 hours with a polymerization step lasting 0.5 hours at 100°C, then 1.5 hours at 120°C, then 2 hours at 130°C.

[0104] In summary, the compositions according to the invention can be used for the preparation of tow-preg usable within 2 to 4 weeks for filament winding applications for type IV hydrogen tanks. These compositions address the problem of curing times by offering polymerization times on thick composite (> 30 mm) of less than 5 hours. In addition, these compositions can be used with both PE (polyethylene) and PA (polyamide) liners, the two main polymer materials used for the manufacture of hydrogen tanks. Finally, these compositions make it possible to replace amine hardeners, which are reprehensible in terms of health.

Claims

Claims

1. Composition (C) comprising (A) 70 to 95 parts by mass of an epoxy resin with a viscosity of between 1 Pa.s and 150 kPa.s at a temperature of between 20°C and 25°C, and (B) 5 to 30 parts by mass of a hardener dispersed in the resin, per 100 parts by mass of resin present in the composition, characterized in that the hardener is an ionic liquid containing a phosphonium cation chosen from PH4+, P(CH3)4+, P(Ph)4+, P(CH3) (Ph)3+, P(CH2OH)4+, and the viscosity is measured at a temperature of between 20°C and 25°C, using an ARES Rheometer device, from TA® instruments Brookfield LV DV 1+ from BROOKFIELD ENGINEERING LABORATORIES, INC.

2. Composition according to claim 1, characterized in that the ionic liquid contains a dicyanamide anion (C2N3).

3. Composition according to claim 2, characterized in that it comprises 10 to 30 parts by mass of ionic liquid, per 100 parts by mass of epoxy resin present in the composition.

4. Composition according to claim 1, characterized in that the ionic liquid contains a phosphinate anion of formula (PO2R5R6) in which R5 and R6, identical or different, represent a hydrogen atom, an alkyl radical having 1 to 18 carbon atoms, an aryl radical having 6 to 20 carbon atoms, said alkyl and aryl radicals being optionally substituted.

5. Composition according to claim 4, characterized in that Tanion phosphinate is chosen from (PO2H2), (PO2(CH3)2), (PO2(C7H30)2), (PO2Ph2).

6. Composition according to one of claims 4 or 5, characterized in that it comprises 5 to 20 parts by mass of ionic liquid, per 100 parts by mass of epoxy resin present in the composition.

7. Composition according to any one of claims 1 to 6, characterized in that the epoxy resin (A) has a viscosity of 16.9 kPa.s (+ / - 20%) at 25°C and of 113.0 kPa.s at 20°C, the viscosity is measured at a temperature between 20°C and 25°C, using an ARES Rheometer device, from the company TA® instruments Brookfield LV DV 1+ from BROOKFIELD ENGINEERING LABORATORIES, INC.

8. Semi-finished product, characterized in that it comprises - a bundle of fibers (F) chosen from carbon, glass, aramid, silicon carbide fibers, organic fibers and - a composition (C) according to any one of claims 1 to 7, said bundle of fibers being impregnated with said composition, and the volume rate of (F) is between 40 and 70% and that of (C) is between 30 and 60%.

9. Use of a composition (C) comprising (A) 70 to 95 parts by mass of an epoxy resin with a viscosity of between 1 Pa.s and 150 kPa.s at a temperature of between 20°C and 25°C, and (B) 5 to 30 parts by mass of a hardener dispersed in the resin, per 100 parts by mass of resin present in the composition, characterized in that the hardener is an ionic liquid containing a phosphonium cation of formula P(RiR2R3R4)+ in which Ri, R2, Ri and R4, which may be identical or different, represent a hydrogen atom, an alkyl radical having 1 to 18 carbon atoms, an aryl radical having 6 to 20 carbon atoms, said alkyl and aryl radicals being optionally substituted, of a composition according to any one of claims 1 to 7, or of a semi-finished product according to claim 8, for the manufacture of a hydrogen tank, in particular a type IV pressure tank, made of composite material, for the on-board storage of gaseous hydrogen.

10. Structure, made of composite material, comprising a semi-finished product or towpreg according to claim 8 polymerized.

11. Structure according to claim 10, characterized in that it is a type IV pressure tank for the on-board storage of gaseous hydrogen.