Rapidly curing low-temperature composition for manufacturing a composite material pressure vessel for storing gaseous hydrogen

Abstract

The present invention relates to a composition (C) comprising, based on 100 parts by mass of the resin present in the composition, 70 to 95 parts by mass of an epoxy resin (A) having a viscosity at a temperature between 20°C and 25°C of 20 Pa·s or less, preferably between 1 and 20, more preferably between 1 and 10, and 5 to 30 parts by mass of a curing agent (B) dispersed in the resin. The curing agent is a phosphonium cation of the formula P(R 1 R 2 R 3 R 4 ) + (wherein R 1 , R 2 , R 3 and R 4 may be the same or different and represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted), and an acetate anion of the formula (R 5 CO 2 ) - (wherein R 5 represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted), or a phosphinate anion of the formula [[(CH 3 ) 3 CCH 2 CH(CH 3 )CH 2 2 P(O)O] - . The present invention also relates to the use of the composition (C) for manufacturing a hydrogen container, in particular a container for storing gaseous hydrogen under pressure and containing a composite material, of types II, III, IV, and V.​

Description

Technical Field

[0001] The present invention relates to containers of types II, III, IV, and V that contain composite materials and function under pressure, and are containers for storing gaseous hydrogen and any other optional gases of interest under pressure, for example, for applications such as hydrogen storage infrastructure, hydrogen transportation for fueling, hydrogen-powered railway vehicles, buses, trucks, aircraft, ships, and other hydrogen-powered vehicles, and hydrogen-powered automobiles, which are fixed, transportable, and mobile, and relates to the field of manufacturing containers for such applications.

Background Art

[0002] Today, although there are onboard storage systems for gaseous hydrogen in pressurized containers for mobile applications, only a few manufacturers are selling thousands or tens of thousands of approved containers per year. Although markets related to low-carbon mobility and pressure storage have emerged, there is no supply chain (transforming raw materials and components into finished products delivered to end customers) that is ready for mass production (in the millions per year) at reasonable costs. For example, storing gaseous hydrogen compactly, reliably, safely, and economically at 700 bar is a major challenge for the widespread commercialization of fuel cell electric vehicles (FCEVs) and other fuel cell applications. Since 2015, several lightweight FCEVs with a range exceeding 500 km have emerged, but onboard hydrogen storage at affordable prices remains a major obstacle, and the number of containers produced remains small. Much of the focus of planned hydrogen storage is on developing cost-effective hydrogen storage technologies with improved energy density (weight capacity of about 6%, i.e., 6% of the mass of the storage system is hydrogen).

[0003] Hydrogen containers for use in automobiles, buses, trucks, trains, aircraft, and ships are already available, but they do not yet meet all the expectations of manufacturers with mass production of hydrogen-powered systems in mind. This also applies to not only the manufacture of H 2 containers but also the deployment and use of fuel cell mobility means.

[0004] The manufacturing costs of type II, III, IV, and V pressure vessels containing composite materials for onboard storage of gaseous hydrogen correspond to approximately 10% - 30% of the cost of the storage system, but high-volume production capacity is a major challenge for automotive integrators. The polymerization process (also called curing or firing) of the composite material matrix that ensures resistance to pressure is currently the main process limiting the speed of container manufacturing. The matrix of the composite material used in pressure vessels is generally an epoxy matrix.

[0005] To produce millions of vehicles per year, the curing time of the matrix of the composite materials used in type II, III, IV, and V fuel containers must be significantly reduced.

[0006] Currently, when using an epoxy matrix, the polymerization (or curing) process of a 700 bar pressure vessel takes about 12 - 16 hours, which is too long for high-volume production as required in the automotive industry.

[0007] For the manufacture of type II, III, IV, and V pressure vessels, the wet filament winding method is generally the most widely used by manufacturers.

[0008] Therefore, there is an actual need for a novel epoxy resin-based composition specialized for the wet filament winding method for the manufacture of type II, III, IV, and V pressure vessels containing composite materials, especially for onboard storage of gaseous hydrogen, which can meet the constraints of high-volume production and is industrially interesting.

[0009] In particular, there is an actual need for the above-mentioned epoxy resin-based composition that can substantially shorten the required time of the polymerization process of the composite material matrix in order to minimize the cycle time of container manufacturing.

[0010] In some cases, especially when the container has an internal coating or liner of polyethylene, the manufacturer may need polymerization at a temperature of 170 °C or lower.

[0011] Therefore, an epoxy resin-based composition as described above is actually required. With this epoxy resin-based composition, when a liner is present, the manufacturer can easily adapt the temperature of the polymerization step to the properties of the liner. In this way, the polymerization step can be optimally carried out at any temperature, even at low temperatures, that is, with a maximum temperature of 170 °C or lower, for example, in the range of 60 °C to 170 °C, 60 °C to 150 °C, 60 °C to 130 °C, 60 °C to 110 °C, 60 °C to 105 °C.

[0012] This low temperature broadens the selection range of materials used for the liner (also called the internal coating), and especially when the thickness of the composite material is large, for example, 2 to 5 cm, the allowable range for controlling the heat generation during curing also increases.

[0013] To achieve the above, the present invention proposes a novel epoxy resin-based composition for composite materials in consideration of the technical and regulatory constraints related to composite material pressure vessels for on-board hydrogen storage of types II, III, IV, and V.

Summary of the Invention

[0014] The present invention is a composition (C) comprising: Based on 100 parts by mass of the resin present in the composition, (A) 70 to 95 parts by mass of an epoxy resin having a viscosity at a temperature between 20 °C and 25 °C of 20 Pa·s or less, preferably between 1 and 20 Pa·s, more preferably between 1 and 10 Pa·s, and (B) 5 to 30 parts by mass of a curing agent dispersed in the resin and the curing agent has the formula P(R 1 R 2 R 3 R 4 ) + (wherein R 1 , R 2 , R3 and R 4 may be the same or different and represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted), a phosphonium cation, and - formula (R 5 CO 2 ) - (wherein R 5 represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted), an acetate anion, or - formula (PO 2 R 6 R 7 ) - (wherein R 6 and R 7 are the same or different and represent a hydrogen atom, an alkyl group having 2 to 16 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted), a phosphinate anion and is an ionic liquid containing relates to a composition (C) characterized by this.

[0015] A container that includes a composite material and functions under pressure is classified into the following categories. - A type II container, called a hoop container, is a metal container generally reinforced by winding fibers circumferentially only on the cylindrical part using carbon or glass (composite reinforcement). - A type III container, which has a metal cover (also called an internal coating or internal liner) that acts as a barrier to gas and a composite reinforcement over the entire outer surface. - A type IV container, which is different from a type III container in that it has a polymer liner. - A type V container, which is different from type IV in that it does not have a polymer liner.

[0016] For example, a type IV pressure vessel made of a composite material consists of an inner coating, also called a liner, made of a polymeric material that is mostly thermoplastic, and has metal connectors called bosses at one or both ends. The bosses connect the container to the storage system. The liner provides a hydrogen tight seal. This assembly is covered with a structured composite material, which ensures that it is structured under internal pressure and usually includes a thermosetting matrix, which is mostly an epoxy resin in most cases, and a reinforcing material based mostly on long fibers, such as carbon or glass.

[0017] Accordingly, an object of the present invention is to assist in the development of an improved onboard compressed gaseous hydrogen storage system (CGH 2 (compressed gaseous hydrogen) compressed gaseous hydrogen, CPV (Composite Pressure Vessel) composite material pressure vessel), which, in particular, focuses on the composition of the composite material of the container, more specifically, the resin and its polymerization reaction that generally have a great influence on the production rate over more than 10 hours, in order to address the future mass deployment of the above-mentioned technology.

[0018] The composition of the present invention is particularly advantageous because it polymerizes rapidly compared to the epoxy matrix compositions currently in use, especially by using a phosphorus ionic liquid as a curing agent. The polymerization time of the epoxy matrix in the composition according to the present invention is less than 12 hours, less than 10 hours, particularly less than 8 hours, particularly less than 6 hours, more specifically less than 4 hours, and even more specifically less than 2 hours.

[0019] The composition of the present invention is also particularly advantageous because, by using an ionic liquid (B) as a curing agent, the polymerization process can be optimally carried out at any temperature, even at low temperatures, i.e., the maximum temperature is 170 °C or less, for example, the maximum temperature is 60 °C to 170 °C, 60 °C to 150 °C, 60 °C to 130 °C, 60 °C to 110 °C, 60 °C to 105 °C.

[0020] As described above, the composition according to the invention takes into account the technical and regulatory constraints associated with composite material containers for on-board hydrogen storage that function under pressure, for example between 200 and 900 bar. This new composition is specifically tailored to the method of wet filament winding most widely used by manufacturers in general.

[0021] Another object of the present invention is - organic fibers selected from polyethylene, poly(p-phenylene-2,6-benzobisoxazole) or PBO, aramid, polyamide, flax, polyester or other organic fibers, - inorganic fibers selected from glass, carbon, silicon carbide, basalt or other inorganic fibers The use of the composition (C) according to the invention for impregnating a bundle of fibers (F) selected therefrom by a wet process.

[0022] The fibers can be impregnated by immersion, contact, injection, or spraying into the bath. These impregnation techniques are well known to those skilled in the art.

[0023] Another object of the present invention is a method for manufacturing a component containing a composite material that functions under pressure, for example between 200 and 900 bar, by wet filament winding, comprising - organic fibers selected from polyethylene, poly(p-phenylene-2,6-benzobisoxazole) or PBO, aramid, polyamide, flax, polyester or other organic fibers, - inorganic fibers selected from glass, carbon, silicon carbide, basalt or other inorganic fibers A method comprising at least one step of impregnating a bundle of fibers (F) selected therefrom with the composition (C) according to the invention.

[0024] More specifically, the method for manufacturing a component containing a composite material that functions under pressure comprises at least the following steps, namely i) a bundle of fibers (F), - Organic fibers selected from polyethylene, poly(p-phenylene-2,6-benzobisoxazole) or PBO, aramid, polyamide, linen, polyester or other organic fibers, - Inorganic fibers selected from glass, carbon, silicon carbide, basalt or other inorganic fibers A step of impregnating a bundle of fibers (F) selected from the above with the composition (C) according to the present invention, ii) A step of winding the impregnated fibers around a liner or mandrel, iii) A step of polymerizing the composition (C) at a temperature of 170 ° C or lower including.

[0025] The above method may also be used, within the scope of the present invention, to manufacture parts including composite materials that do not need to function under pressure.

[0026] The composite part can be a type II, III, IV or V pressure vessel for gaseous hydrogen storage. Preferably, the part is a type IV container.

[0027] The impregnation can be carried out by immersion in a bath containing the composition (C) according to the present invention, contact with the composition (C) according to the present invention, injection or spraying of the composition (C) according to the present invention.

[0028] The polymerization can be carried out at a maximum temperature of 170 ° C or lower, for example, at a maximum temperature of 60 ° C to 170 ° C, 60 ° C to 150 ° C, 60 ° C to 130 ° C, 60 ° C to 110 ° C, 60 ° C to 105 ° C. The temperature is selected by the manufacturer according to the respective manufacturing constraints.

[0029] The bundle of the fibers (F) is impregnated with the composition (C) such that the mass ratio of (F) is between 40 and 70% and the mass ratio of (C) is between 30 and 60%.

[0030] The bundle of fibers can be in the form of rovings, ribbons, non-woven webs, or loose fiber aggregates, or in a woven form.

[0031] Using the composition (C) according to the present invention, containers for gaseous hydrogen storage under pressure, of types II, III, IV and V, containing composite materials, are manufactured, in particular, for both stationary and mobile applications such as, for example, hydrogen storage infrastructure, hydrogen transport for refueling, hydrogen-powered railway vehicles, buses, trucks, aircraft, ships and other hydrogen-powered vehicles, and hydrogen-powered motor vehicles.

[0032] Accordingly, an object of the present invention is the use of the composition (C) according to the present invention for the manufacture of hydrogen containers, in particular pressure vessels for gaseous hydrogen storage made of composite materials, of types II, III, IV and V.

[0033] In the context of the present invention, a component or a container is considered to function under pressure when the nominal functional pressure is on the order of several hundred bar, for example when the nominal functional pressure is between 200 and 900 bar.

Embodiments for Carrying Out the Invention

[0034] Detailed Description of the Invention The present invention relates to a composition (C) comprising, with respect to 100 parts by mass of the resin present in the composition, (A) 70 to 95 parts by mass of an epoxy resin having a viscosity at a temperature between 20°C and 25°C of 20 Pa·s or less, preferably between 1 and 20 Pa·s, more preferably between 1 and 10 Pa·s, and (B) 5 to 30 parts by mass of a curing agent dispersed in the resin and the curing agent is of the formula P(R 1 R 2 R 3 R 4 ) + (wherein R 1 , R 2 , R 3 and R 4 may be the same or different and represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted), a phosphonium cation, and - A formula (R 5 CO 2 ) - (wherein, R 5 represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted), or an acetate anion, or - A formula (PO 2 R 6 R 7 ) - (wherein, R 6 and R 7 are the same or different and represent a hydrogen atom, an alkyl group having 2 to 16 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted), and a phosphinate anion, and is an ionic liquid containing Characterized in that it relates to a composition (C).

[0035] Regarding the object of the present invention, the "alkyl" group generally includes 1 to 18 carbon atoms, for example 1 to 14 carbon atoms, for example 1 to 10 carbon atoms, and may be a linear, branched or cyclic saturated carbon group which may be substituted. Examples of linear or branched saturated alkyls include methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, and their branched isomers. Examples of cyclic alkyl groups include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, bicyclo[2,1,1]hexyl group, and bicyclo[2,2,1]heptyl group.

[0036] In a specific case of the phosphinate anion, the "alkyl" group generally includes 2 to 16 carbon atoms, for example 4 to 16 carbon atoms, and may be a linear, branched or cyclic saturated carbon group which may be substituted.

[0037] The term "aryl" generally refers to a monocyclic or polycyclic aromatic substituent containing 6 to 20 carbon atoms, for example 6 to 10 carbon atoms. Examples include phenyl group, benzyl group, naphthyl group, and phenanthrenyl group.

[0038] The alkyl group and the aryl group may be substituted with 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 selected from fluorine atom, chlorine atom, bromine atom and iodine atom, and alkyl and aryl are as defined in the context of the present invention.

[0039] In the phosphonium cation, R 1 , R 2 , R 3 , and R 4 may be the same or different, - a hydrogen atom, - an alkyl group selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl and their branched isomers, - an aryl group selected from phenyl and benzyl represents, the alkyl group and the aryl group may be substituted.

[0040] The phosphonium cation is [(C 6 H 13 ) 3 (C 14 H 29 )P] + , [(C 4 H 9 ) 3 (C 14 H 29 )P] + , [(C 4 H 9 ) 3 (C 2 H 5 )P] + , [(C 8 H17 ) 4 P] + 、[(C 4 H 9 ) 3 (CH 3 )P] + 、[(iso-C 4 H 9 ) 3 (CH 3 )P] + 、[(H) 4 P] + 、[(CH 3 ) 4 P] + 、[(Ph) 4 P] + 、[(Ph) 3 (CH 3 )P] + 、[(C 6 H 13 ) 3 (C 14 H 29 )P] + 、[(CH 2 OH) 4 P] + and can be selected from the following.

[0041] More specifically, the phosphonium cation is [(C 6 H 13 ) 3 (C 14 H 29 )P] + 、[(C 4 H 9 ) 3 (C 14 H 29 )P] + 、[(C 4 H 9 ) 3 (C 2 H 5 )P] + 、[(C 8 H 17 ) 4 P] + 、[(C 4 H 9 ) 3 (CH 3 )P] + 、[(iso-C 4 H9 ) 3 (CH 3 )P] + 、[(C 6 H 13 ) 3 (C 14 H 29 )P] + may be selected from.

[0042] According to the first embodiment of the present invention, in the composition, the ionic liquid is of the formula (PO 2 R 6 R 7 ) - (wherein R 6 and R 7 may be the same or different and represent a hydrogen atom, an alkyl group having 2 to 16 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted) phosphinate anion and the phosphonium cation defined above.

[0043] In this first embodiment, the phosphinate anion of the formula (PO 2 R 6 R 7 ) - , wherein R 6 and R 7 may be the same or different, - a hydrogen atom, - an alkyl group selected from butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl and their branched isomers, - an aryl group selected from phenyl and benzyl is represented, and the alkyl group and the aryl group may be substituted.

[0044] The phosphinate anion is (PO 2 H 2 ) - , (PO 2 (C 7 H 30 ) 2 ) -, [[(CH 3 ) 3 CCH 2 CH(CH 3 )CH 2 2 P(O)O] - , (PO 2 Ph 2 ) - may be selected from.

[0045] The ionic liquid may contain a phosphinate anion of the formula [[(CH 3 ) 3 CCH 2 CH(CH 3 )CH 2 2 P(O)O] - and the phosphonium cation defined above.

[0046] In this first embodiment, the ionic liquid may be trihexyl(tetradecyl)phosphonium bis-2,4,4-(trimethylpentyl)phosphinate, or CYPHOS® IL104 of Cytec Industries Inc.

[0047] In this first embodiment, when the ionic liquid contains the above phosphinate anion, the composition contains 5 to 20 parts by mass of the ionic liquid or ionic liquids with respect to 100 parts by mass of the epoxy resin present in the composition.

[0048] In all variations and embodiments of the present invention, the composition (C) may be polymerized under the action of a temperature according to the desired use and desired properties. Those skilled in the art can select and adapt these conditions.

[0049] According to a second embodiment of the present invention, the composition has the formula (R 5 CO 2 ) - (wherein R 5 ​​represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted), and an ionic liquid containing an acetate anion and the phosphonium cation defined above.

[0050] In this second embodiment, in the acetate anion, R 5 is - a hydrogen atom, - methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, and their branched isomers, and an alkyl group selected from their branched isomers, - an aryl group selected from phenyl and benzyl represents, and the alkyl group and the aryl group may be substituted.

[0051] The acetate anion is ((CH 3 )CO 2 ) - , ((C 5 H 11 )CO 2 ) - , ((CH 3 CH 2 CH(CH 3 )CH 2 CH 2 )CO 2 ) - , ((C 7 H 15 )CO 2 ) - , ((CH 3 CH 2 CH 2 CH 2 CH(CH 3 )CH 2 CH 2 )CO 2 ) - , ((CH 3 ) 3 CCH 2 CH(CH 3 )CH 2 CH 2CH 2 )CO 2 ) - 、(CH 3 CH(CH 3 )CH 2 CH 2 CH 2 CH(CH 3 )CH 2 )CO 2 ) - 、((C 9 H 19 )CO 2 ) - may be selected from.

[0052] In this second embodiment, when the ionic liquid contains the above-mentioned acetate anion, the composition contains 5 to 20 parts by mass of the ionic liquid with respect to 100 parts by mass of the epoxy resin present in the composition.

[0053] On the other hand, in this embodiment, the ionic liquid may be trihexyl(tetradecyl)phosphonium decanoate or CYPHOS® IL 103 of Strem Chemicals Inc.

[0054] The epoxy resin (A) present in the composition may be, for example, a bisphenol type such as bisphenol A, bisphenol B, bisphenol F, bisphenol S, ortho-, meta-, para-cresol novolak.

[0055] The epoxy resin (A) may be Araldite® LY 566 bisphenol A resin commercially available from Huntsman.

[0056] The epoxy resin (A) has a viscosity at a temperature between 20 °C and 25 °C of 20 Pa·s or less, preferably between 1 and 20 Pa·s, more preferably between 1 and 10 Pa·s.

[0057] Viscosity was measured at a temperature between 20 °C and 25 °C using an ARES rheometer device from TA (registered trademark) Instruments. For the ARES rheometer, a plane / plane configuration of aluminum disks with 25 mm (upper shape) and 40 mm (lower shape) was used. The composition was deposited onto those shapes at an elevated temperature (60 °C) and then cooled between 20 °C and 25 °C to measure the viscosity. A dynamic frequency sweep (DFS) (strain control) test from 1 to 100 rad / s was performed at a strain of approximately 10%. Viscosity measurements were taken at a frequency of 6 rad / s.

[0058] The composition according to the present invention can be prepared, as shown in the examples, by mixing elements (A) and (B). In particular, this method consists of mixing the epoxy resin (A) and the ionic liquid (B) as defined above at a temperature at which the polymerization of (A) is not initiated to obtain a homogeneous composition.

[0059] The composition can be prepared in air in a simple reactor (made of glass) equipped with a stirring blade. The temperature can be controlled by a hot plate and a silicone oil bath.

[0060] Continuous mixing is a method in which components are directly and continuously introduced into a mixing zone to generate a continuous flow of the mixed product at the outlet of the mixer. By this principle, complete control of the confluence point of the components is ensured, thereby guaranteeing the specific distribution quality of the mixed product. Thus, the resulting product is in the form of a homogeneous mixture. Any continuous mixer known to those skilled in the art may be suitable for making the composition.

[0061] Although not wishing to be bound by theory, the inventors have found that when the above ionic liquid is used as a curing agent in the compositions according to the invention, polymerization by a catalytic mechanism rather than an addition mechanism becomes possible. The ionic liquid makes it possible to reduce the amount of curing agent (curing agent or hardener) necessary to fully cure the epoxy matrix (i.e., in the case of standard amines, 20 to 50 parts or 20 to 50 phr per 100 parts of resin). In fact, the ionic liquid causes the oxirane ring to open by nucleophilic attack of the anion on the α-carbon of the functional group under the influence of temperature.

[0062] This reaction, called the activation reaction, forms a functional group, an alcoholate, which is reactive towards other epoxide units. The second step, called propagation, consists of the homopolymerization of the alcoholate units formed in the oxirane ring.

[0063] Under suitable temperature conditions, this reaction continues until the epoxy matrix is fully crosslinked (polymerization rate > 95%).

[0064] It should be noted that by using the above ionic liquid, in composition (C), the polymerization is rapid compared to the epoxy matrix compositions currently in use. The polymerization time of the epoxy matrix in composition (C) according to the invention is less than 12 hours, less than 10 hours, particularly less than 8 hours, particularly less than 6 hours, more particularly less than 4 hours, and even more particularly less than 2 hours.

[0065] Another object of the present invention is the use of composition (C) according to the invention for impregnating bundles of fibers (F) by a wet process, the fibers (F) being - organic fibers selected from polyethylene, poly(p-phenylene-2,6-benzobisoxazole) or PBO, aramid, polyamide, linen, polyester or other organic fibers, - inorganic fibers selected from glass, carbon, silicon carbide, basalt or other inorganic fibers selected from.

[0066] The bundle of fibers (F) can be in the form of rovings, ribbons, non-woven webs, or assemblies of loose fibers, or in a woven form.

[0067] The bundle of reinforcing fibers preferably contains 1,000 to 70,000 filaments with a diameter of 3 to 100 μm.

[0068] Preferably, the fiber (F) is a carbon fiber. Examples of carbon fibers include Toray (registered trademark) T720 carbon fiber.

[0069] Another object of the present invention is a method for manufacturing a component containing a composite material that functions under pressure, which is carried out by wet filament winding, - an organic fiber selected from polyethylene, poly(p-phenylene-2,6-bisoxazole) or PBO, aramid, polyamide, linen, polyester or other organic fibers, - an inorganic fiber selected from glass, carbon, silicon carbide, basalt or other inorganic fibers A method including at least one step of impregnating a bundle of fibers (F) selected from the above. The composition (C) according to the present invention.

[0070] More specifically, the method for manufacturing a component containing a composite material that functions under pressure includes at least the following steps, namely i) A bundle of fibers (F), - an organic fiber selected from polyethylene, poly(p-phenylene-2,6-bisoxazole) or PBO, aramid, polyamide, linen, polyester or other organic fibers, - an inorganic fiber selected from glass, carbon, silicon carbide, basalt or other inorganic fibers A step of impregnating the bundle of fibers (F) selected from the above with the composition (C) according to the present invention, ii) A step of winding the impregnated fibers around a liner or mandrel, iii) A step of polymerizing the composition (C) at a temperature of 170 °C or lower is included.

[0071] As already described, the method of the present invention also enables the production of parts containing composite materials that do not need to function under pressure, within the scope of the meaning of the present invention.

[0072] The parts containing the composite material can be containers for storing gaseous hydrogen under pressure of types II, III, IV and V. Preferably, the part is a type IV container.

[0073] Implementation by wet filament winding is a method well known to those skilled in the art. In the context of this method, the fiber (F) is continuously supplied from a roller, passes through a bath containing the composition (C), and is then wound around a liner or mandrel.

[0074] The bundle of the fibers (F) is impregnated with the composition (C) such that the mass ratio of (F) is between 40% and 70%, and the mass ratio of (C) is between 30% and 60%.

[0075] The bundle of fibers (F) can be in the form of rovings, ribbons, non-woven webs, or an assembly of loose fibers, or in a woven form.

[0076] In step i), the impregnation of the moving fiber bundle (F) with the composition (C) is carried out continuously in a bath containing the composition (C) according to the present invention at a temperature that can be in the range of 10 to 80 °C, for example 10 to 50 °C.

[0077] The required time for this impregnation can be in the range of several seconds to several minutes, for example 10 seconds to 5 minutes.

[0078] The impregnation bath contains the composition (C) according to the present invention.

[0079] After step (i), the impregnated fibers are wound around a mandrel at a temperature of 30 °C or lower, for example between 20 and 30 °C.

[0080] In step (i), the bundle of fibers (F) can be impregnated with the composition (C) using techniques well known to those skilled in the art as described above.

[0081] The bundle of fibers (F) is impregnated with the composition (C) such that the mass ratio of (F) is between 40% and 70%, and the mass ratio of (C) is between 30% and 60%.

[0082] Implementation by wet filament winding is particularly suitable for the manufacture of parts containing composite materials that function at the nominal functional pressure defined above, such as storage containers that function under pressure.

[0083] The step of winding the impregnated fibers (ii) is carried out continuously around a rotating mandrel. The winding is carried out around a polymer liner for a type IV container, or around a metal mandrel for type II and type III containers, or around a soluble or removable mandrel for type V containers.

[0084] The fiber deposition system is implemented by fiber guidance that moves longitudinally and transversely during rotation of the liner or mandrel so that the fibers are wound and / or deposited uniformly.

[0085] For the manufacture of cylindrical or spherical parts, two fiber deposition methods can be used. Circumferential winding, where the fiber layers are deposited at an angle of 90° with respect to the axis of the liner, and helical winding, where the fiber layers are deposited at an angle other than 90°. These two techniques are well known to those skilled in the art and are described, for example, in Hojjati et al., Composites Engineering, Vol. 5, pp. 51 - 59, 1995; De Carvalho et al., Composites Manufacturing, Vol. 6, pp. 79 - 84, 1995; Koussios et al., Journal of Materials Design and Applications, Vol. 219, pp. 25 - 35, 2005; Zu et al., Interfacial Interactions in Composites and Other Applications, Vol. 41, pp. 1312 - 1320, 2010.

[0086] At the end of the winding deposition stage, in step iii), polymerization can be carried out at a maximum temperature of 170°C or less, for example, at a maximum temperature of 60°C - 170°C, 60°C - 150°C, 60°C - 130°C, 60°C - 110°C, 60°C - 105°C. The temperature is selected by the manufacturer according to their respective manufacturing constraints.

[0087] This step iii) is generally carried out in an oven or a tunnel furnace. The heating is maintained until the epoxy matrix of the composition (C) is completely polymerized (polymerization rate > 95%).

[0088] Filament winding can also be carried out on a polymer liner, particularly a polyethylene or polyamide liner.

[0089] The liner is an internal coating of the container. It has two main functions: sealing the structure and acting as a mandrel. By rotating the liner, the fibers pre - impregnated with the composition (C) are directly deposited on the outer surface of the liner.

[0090] In one embodiment, the liner is made of polyethylene.

[0091] In another embodiment, the liner is made of polyamide.

[0092] In another embodiment, the liner is a metal such as aluminum or stainless steel.

[0093] The composition (C) according to the invention cures rapidly (in a few hours) at low temperature during the manufacture of composite pressure vessels for gaseous hydrogen storage of types II, III, IV and V, as described above. The ability of the composition to cure rapidly and at low temperature is essentially due to the use of the ionic liquid (B) as a curing agent.

[0094] The composition (C) comprises an epoxy resin (A) because this type of thermosetting polymer is most commonly used in the manufacture of pressure vessels for onboard hydrogen storage.

[0095] Thus, using the composition (C) according to the invention, composite pressure vessels of types II, III, IV and V can be manufactured for both stationary and mobile applications, such as hydrogen storage infrastructure, hydrogen transport for refueling, hydrogen-powered railway vehicles, buses, trucks, aircraft, ships and other hydrogen-powered vehicles, and hydrogen-powered automobiles, for gaseous hydrogen storage.

[0096] Accordingly, an object of the present invention is the use of the composition (C) according to the invention for the manufacture of hydrogen containers, in particular containers for gaseous hydrogen storage under pressure, of types II, III, IV and V, which contain composite materials.

[0097] The containers thus obtained can be approved according to the criteria of currently applicable regulations (such as EC 79 or R134).

Examples

[0098] Protocol for the preparation of the composition according to the invention The Araldite® LY 566 bisphenol A epoxy resin commercially available from Huntsman has a viscosity of 10 Pa·s at 20°C. The Araldite® LY 566 epoxy resin is liquid at room temperature (20°C to 25°C).

[0099] The resin is introduced into a thermostat-controlled reactor, and then Cyphos® IL 104 (trihexyl(tetradecyl)phosphonium bis-2,4,4-(trimethylpentyl)phosphinate or [R 4 PA]), an ionic liquid commercially available from Cytec Industries Inc., or Cyphos® IL 103 (trihexyl(tetradecyl)phosphonium decanoate), an ionic liquid commercially available from Strem Chemicals, is added at a ratio of 10 parts by mass or 10 pp or 10 phr (10 parts of Cyphos® LI 103 per 100 parts of LY 556 resin). The mixture is stirred at 40°C for about 20 minutes.

[0100] When homogenized, the composition according to the present invention is obtained, and it can be used to impregnate reinforcing fibers. During this process, the composition is continuously diffused onto Torayca T720 carbon fiber rovings at a temperature between 10 and 50°C. This temperature can be adjusted by those skilled in the art.

[0101] Next, the rovings impregnated with the composition (resin + ionic liquid) can be wound around a liner.

[0102] Curing cycle The curing cycle proposed for polymerizing the composition prepared above is 5 hours, and the duration of the polymerization step is For the Cyphos® IL 104 ionic liquid, 2 hours at 80°C, then 3 hours at 130°C, or 2 hours at 80°C, then 3 hours at 105°C, For Cyphos® IL 103, 1 hour at 50°C, then 1 hour at 70°C, then 3 hours at 105°C or 130°C is.

[0103] In summary, using the composition according to the present invention, containers for wet filament winding applications, particularly for type IV hydrogen vessels, can be prepared in 1 to 2 days. The composition addresses the curing time issue for thick composites (>30 mm) by setting the polymerization time to less than 5 hours. Further, the composition can be used with liners of two main polymer materials, polyethylene (PE) and polyamide (PA), which are used to manufacture type IV hydrogen vessels. Finally, the composition makes it possible to replace the amine curing agent that is harmful to health.

Claims

1. Composition (C), With respect to 100 parts by mass of resin present in the above composition, (A) 70 to 95 parts by mass of epoxy resin having a viscosity of 20 Pa·s or less at a temperature between 20°C and 25°C, (B) 5 to 30 parts by mass of a curing agent dispersed in the resin and Includes, The hardener is of the formula P(R １ R ２ R ３ R ４ ) ＋ (wherein R １ , R ２ , R ３ and R ４ may be the same or different and each represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and the alkyl group and the aryl group may be substituted) and a phosphonium cation of -Formula (R ５ CO ２ ) － (In the formula, R ５ (where represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, and an aryl group having 6 to 20 carbon atoms, and the alkyl group and aryl group may be substituted) an acetate anion and The ionic liquid contains the above, and its viscosity is measured at a temperature between 20°C and 25°C using an ARES rheometer from T.A. Instruments, Inc. A composition (C) characterized by the following.

2. In the phosphonium cation, R １ , R ２ , R ３ , and R ４ However, they may be the same or different. - Hydrogen atom, - Alkyl alkyl groups selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl and their branched isomers, - Aryl group selected from phenyl and benzyl This represents, The alkyl and aryl groups may be substituted. The composition according to claim 1, characterized in that...

3. The phosphonium cation is [(C ６ H １３ ) ３ (C １４ H ２９ ) P] ＋ [(C ４ H ９ ) ３ (C １４ H ２９ ) P] ＋ [(C ４ H ９ ) ３ (C ２ H ５ ) P] ＋ [(C ８ H １７ ) ４ P) ＋ [(C ４ H ９ ) ３ (CH ３ ) P] ＋ [(iso-C ４ H ９ ) ３ (CH ３ ) P] ＋ [(H) ４ P) ＋ [(CH ３ ) ４ P) ＋ [(Ph) ４ P) ＋ [(Ph) ３ (CH ３ ) P] ＋ [(C ６ H １３ ) ３ (C １４ H ２９ ) P] ＋ [(CH ２ OH) ４ P) ＋ The composition according to claim 1 or 2, characterized by being selected from among.

4. The aforementioned ionic liquid is given by formula (R ５ CO ２ ) － It contains the acetate anion, in the formula, R ５ teeth, - Hydrogen atom, - Methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl and their branched isomers, and alkyl groups selected from their branched isomers, - Aryl group selected from phenyl and benzyl This represents, The alkyl and aryl groups may be substituted. The composition according to claim 1 or 2, characterized in that...

5. The acetate anion is ((CH ３ )CO ２ ) － , ((C ５ H １１ )CO ２ ) － , ((CH ３ CH ２ CH(CH ３ )CH ２ CH ２ )CO ２ ) － , ((C ７ H １５ )CO ２ ) － , ((CH ３ CH ２ CH ２ CH ２ CH(CH ３ )CH ２ CH ２ )CO ２ ) － , ((CH ３ ) ３ CCH ２ CH(CH ３ )CH ２ CH ２ CH ２ )CO ２ ) － , (CH ３ CH(CH ３ )CH ２ CH ２ CH ２ CH(CH ３ )CH ２ )CO ２ ) － , ((C ９ H １９ )CO ２ ) － selected from The composition according to claim 4, characterized in that...

6. The composition according to claim 1 or 2, characterized in that it contains 5 to 20 parts by mass of ionic liquid with respect to 100 parts by mass of epoxy resin present in the composition.

7. Use of composition (C) according to claim 1, wherein the composition is With respect to 100 parts by mass of resin present in the above composition, (A) 70 to 95 parts by mass of epoxy resin having a viscosity of 20 Pa·s or less at a temperature between 20°C and 25°C, (B) 5 to 30 parts by mass of a curing agent dispersed in the resin and Includes, The aforementioned hardening agent is of formula P(R １ R ２ R ３ R ４ ) ＋ (In the formula, R １ , R ２ , R ３ and R ４ (as defined in claim 1) a phosphonium cation, -Formula (PO ２ R ６ R ７ ) － A phosphinate anion of which, in the formula, R ６ and R ７ They may be the same or different. - Hydrogen atom, -alkyl groups selected from butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl and their branched isomers, - Aryl group selected from phenyl and benzyl This represents, The alkyl and aryl groups may be substituted with hydrogen atoms, alkyl groups having 2 to 16 carbon atoms, or aryl groups having 6 to 20 carbon atoms, and the alkyl and aryl groups may be substituted. It is an ionic liquid containing a phosphinate anion, The aforementioned use is, - Organic fibers selected from polyethylene, poly(p-phenylene-2,6-benzobisoxazole) or PBO, aramid, polyamide, flax and polyester fibers. - Inorganic fibers selected from glass, carbon, silicon carbide, and basalt fibers A method for impregnating bundles of selected fibers (F) by a wet process.

8. If the composition used contains a curing agent which is an ionic liquid containing a phosphinate anion, then the phosphinate anion is of the formula [[(CH ３ ) ３ CCH ２ CH (CH ３ )CH ２ ] ２ P(O)O] － The use according to claim 7, characterized in that it is of the same nature.

9. A method for manufacturing a component containing a composite material that functions under pressure, comprising at least the following steps: i) A bundle of fibers (F), - Organic fibers selected from polyethylene, poly(p-phenylene-2,6-benzobisoxazole) or PBO, aramid, polyamide, flax and polyester fibers. - Inorganic fibers selected from glass, carbon, silicon carbide, and basalt fibers A step of impregnating a bundle of fibers (F) selected from the above with the composition (C) described in claim 1 or 2, or the composition defined in claim 7 or 8. ii) A step of winding the impregnated fibers around a liner or mandrel, iii) A step of polymerizing composition (C) at a temperature of 170°C or lower. A method characterized by including

10. The method according to claim 9, characterized in that a bundle of the fibers (F) is impregnated with the composition (C) described in claim 1 or 2, or the composition defined in any one of claim 7 or 8, in a mass ratio of (F) between 40% and 70% and a mass ratio of (C) between 30% and 60%.

11. Use of the composition (C) according to claim 1 or 2 for manufacturing hydrogen containers, in particular Type II, III, IV and V, which function under pressure and include composite materials for gaseous hydrogen storage.