Methods and controlled environment assembly line for producing gas storage vessels

Abstract

A controlled environment assembly line suitable for producing articles such as gas storage vessels. The assembly line processes continuous fibers and a resin composition including one or more of cyclic monomers and oligomers under specific conditions to produce articles such as robust, pressure-resistant, high strength gas storage vessels including high continuous fiber loadings in a polymer system derived from the one or more of cyclic monomers and / or oligomers. Methods for producing gas storage vessels utilizing the assembly line are also disclosed.

Description

METHODS AND CONTROLLED ENVIRONMENT ASSEMBLY LINE FOR PRODUCING GAS STORAGE VESSELSFIELD OF THE INVENTION

[0001] The present invention relates to a controlled environment assembly line suitable for producing articles such as gas storage vessels. The assembly line processes continuous fibers and a resin composition including one or more of cyclic monomers and oligomers under specific conditions to produce articles such as robust, pressure-resistant, high strength gas storage vessels including high continuous fiber loadings in a polymer system derived from the one or more of cyclic monomers and / or oligomers. Methods for producing gas storage vessels utilizing the assembly line are also disclosed.BACKGROUND OF THE INVENTION

[0002] Alternative fuel sources are sought throughout the world to replace fossil fuels as primary energy sources, especially for the transportation field.

[0003] While electric batteries provide one means to replace fossil fuels, drawbacks exist. For example, most electric batteries alone are not powerful enough to move heavy trucks, trains and airplanes. In addition, long charging times inhibit adoption of electric battery technology. For commercial vehicles, long charging times mean reduced productivity since the vehicles are idle during charging.

[0004] Hydrogen is another alternative fuel that can be produced using solar power and wind power which can be stored and transported. Hydrogen generated through the use of green energy such as solar power, wind power, wave energy or hydroelectricity is considered green hydrogen.

[0005] Green hydrogen is the ultimate renewable and clean energy for the hydrogen economy. For storage of hydrogen, there are multiple solutions for stationary storage that can be installed and used by power plants, utility microgrids, manufacturing facilities, and even households. However, for cars, trucks, trailers, airplanes, etc., storing and transporting hydrogen is still the most challenging task.

[0006] Traditional gas storage vessels are typically made of metal, which are heavy and difficult to transport. Metal storage vessels are also prone to corrosion and damage.

[0007] Storage vessels for hydrogen, natural gas or other gases in which safety is of utmost importance should be light in weight, durable and able to withstand high pressures, such as at least 700 bar (70 mPa) for hydrogen.

[0008] In order to meet these requirements, storage tanks fabricated with continuous fiber reinforced thermosetting composite materials have been developed in the art. However, recycling and reuse of thermoset composite materials is a drawback, even though relatively high fiber loadings can be achieved, and high strength vessels can be produced.

[0009] In an effort to overcome the drawbacks of gas storage vessels prepared utilizing thermoset composite materials, thermoplastic composite material gas storage vessels have also been developed.

[0010] U.S. 2018 / 0363849 relates to a pressure vessel comprising a hollow body comprising endless fibers embedded in a thermoplastic polymer, in which the thermoplastic polymer comprises one or more polyamides containing one or more aliphatic monomeric units, wherein the one or more polyamides have a CH2-ratio of at least 5.5 and less than 10, calculated by identifying the number of different aliphatic monomeric units in the one or more polyamides; determining the number of CH2 groups per aliphatic monomeric unit for each of these different aliphatic monomeric units; calculating the sum of the so determined numbers of CH2 groups; dividing said sum by the number of different aliphatic monomeric units in the one or more polyamides; taking into account only the aliphatic monomeric units present in the one or more polyamides in an amount of at least 10 wt.% with respect to the total weight of the one or more polyamides.

[0011] CN115625913 relates to the technical field of pressure containers and hydrogen energy sources, and discloses a thermoplastic polyimide composite material winding layer type IV gas cylinder preparation method, which comprises the following steps: preparing a monomer resin solution from a dianhydride monomer and a diamine monomer, placing the monomer resin solution in a gum dipping tank, and transverselypenetrating through a continuous fiber bundle; heating to enable in-situ amidization polymerization to form polyamide acid prepreg, and winding the polyamide acid prepreg on the surface of the liner of the type IV plastic gas cylinder; and heating to produce thermoplastic polyimide and carrying out air tightness detection. The gas cylinder inner container and the winding layer resin base body are both made of thermoplastic resin and can be recycled. The inner container of the gas cylinder is a plastic inner container, and the working pressure can reach 35 MPa. The drawback of this chemistry and process is that it requires the use of a solvent to dissolve dianhydride and diamine monomers and an additional step of heat treatment to remove the residual solvent. In addition, it requires high polymerization temperature in a range that is higher than the melting point or softening point of some of the inner liner plastics such as polyethylene, polypropylene, polystyrene, polycarbonate, polyvinyl chloride, ethylene vinyl alcohol, and some polyesters and polyamides.

[0012] Even in view of these attempts to provide methods for producing storage vessels that are ultimately recyclable and reusable, there is still a need for high strength, pressure- resistant gas storage vessels including a continuous fiber thermoplastic composite material having high fiber loadings, for example at least 60% by weight or at least 70% by weight or more and methods to produce gas storage tanks that are economical and relatively easy to utilize.SUMMARY OF THE INVENTION

[0013] The problems of the prior art and others are solved by the present invention which provides gas storage vessels including a structural layer including a continuous fiber thermoplastic composite material in which the continuous fiber is present at a relatively high loading based on total weight of continuous fiber and polymer in the layer. Continuous fiber thermoplastic composite materials are also disclosed herein. Methods for producing gas storage tanks comprising continuous fiber thermoplastic composite materials are additionally described. Still further, continuous fiber processing assembly lines for producing articles including the gas storage vessels in a controlled environment are discussed in depth.

[0014] In one aspect or embodiment, a gas storage vessel is disclosed, comprising a liner having a hollow body with an internal volume that is adapted to store a gas such as hydrogen, and a pressure-resistant structural layer disposed on at least one portion of an outer surface of the liner. The liner is optional in some embodiments. The structural layer includes a continuous fiber thermoplastic composite material in which the continuous fiber is present at a high loading based on the total weight of the thermoplastic polymer and continuous fiber in the structural layer. The thermoplastic polymer is derived from at least one or more of cyclic monomers and / or oligomers including a cyclic group, that can undergo ring opening polymerization.

[0015] In a further aspect or embodiment, the continuous fiber loading is at least 60%, at least 70%, at least 80% or at least 85% by weight based on the total weight of continuous fiber and polymer in the structural layer.

[0016] In an additional aspect or embodiment, the structural layer includes the continuous fiber wound around at least one portion of the liner in a spiral pattern, in a longitudinal direction, circumferential direction, or in a lateral direction, or a combination thereof.

[0017] In yet a further aspect or embodiment, the continuous fiber comprises one or more of a glass fiber, a carbon fiber, an aramid fiber, a basalt fiber, an ultra-high molecular weight polyethylene fiber, a boron fiber, and a natural fiber.

[0018] Still another aspect or embodiment of the present invention relates to providing a gas storage vessel having an operating pressure between 1 bar (0.1 mPa) and 1 ,500 bars (150 mPa), preferably between 1 bar (0.1 mPa) and 1000 bars (100 mPa), more preferably between 1 bar (0.1 mPa) and 700 bars (70 mPa) meeting type IV pressure vessel requirement.

[0019] Another aspect or embodiment of the present invention relates to a method for producing a gas storage vessel, comprising the steps of: obtaining a continuous fiber processing assembly line located in a controlled environment which has a relative humidity of less than 40%, preferably less than 30%, more preferably less than 20% as measured by a psychrometry following ASTM E337 test standard (2024); wherein the assembly line comprises: a continuous fiber source including at least one continuousfiber; a resin source including a resin composition, wherein the resin composition includes one or more of cyclic monomers and oligomers including a cyclic group; an applicator device for contacting the continuous fiber and the resin composition; and a winding device that receives the continuous fiber thermoplastic composite material produced by the applicator device; contacting a portion of the at least one continuous fiber with the resin composition using the applicator device to produce a resin wetted continuous fiber; transferring the resin wetted continuous fiber to a winding device and using the winding device to form at least a portion of a structural layer of a gas storage vessel with the resin wetted continuous fiber; polymerizing the resin composition at a time after it is contacted with the at least one continuous fiber to form a thermoplastic polymer , wherein the at least one continuous fiber is present at a loading of at least 60% by weight, based on the total weight of the thermoplastic polymer and continuous fiber in the structural layer.

[0020] In a further aspect or embodiment, the continuous fiber source includes a plurality of continuous fibers, wherein the continuous fibers are one or more of a glass fiber, an aramid fiber, a carbon fiber, a basalt fiber, an ultra-high molecular weight polyethylene fiber, a boron fiber, and a natural fiber, and the method includes the step of feeding the plurality of continuous fibers to a fiber spreader which arranges the plurality of continuous fibers at a desired orientation and spacing between the plurality of continuous fibers.

[0021] In an additional aspect or embodiment, the method further includes the step of processing the plurality of continuous fibers in a moisture reduction unit so that a moisture content thereof is at or below 0.1 %, preferably below 0.01 % as measured using a moisture analyzer with a proper detection limit prior to contacting the plurality of continuous fibers with the resin composition using the applicator device.

[0022] In yet a further aspect or embodiment, the assembly line further includes a packing and polymerization unit located downstream from the applicator device, and further including the step of polymerizing the resin composition including the one or more of the cyclic monomers and oligomers in the packing and polymerization unit in the form of a die.

[0023] In still another aspect or embodiment, the resin source includes a first tank with a first feedstock comprising the resin composition and an activator, wherein the resin source includes a second tank with a second feedstock comprising the resin composition and a catalyst, wherein the resin source includes a mixing device, further includes the step of combining the first feedstock and the second feedstock with the mixing device to form a mixed resin composition, and further including the step of feeding the mixed resin composition to the applicator device.

[0024] In still a further aspect or embodiment, the method further includes the step of using the applicator device to contact the plurality of continuous fibers with the mixed resin composition to form a plurality of resin wetted continuous fibers.

[0025] In an additional aspect or embodiment, the method further includes the step of passing the resin wetted continuous fibers through a heating device to a guide and then subsequently to the winding device.

[0026] In a still further aspect or embodiment, the method further includes the step of using the winding device to apply the plurality of resin wetted continuous fibers to a form and creating at least a portion of the structural layer of the gas storage vessel.

[0027] In another aspect or embodiment, the method further includes the steps of heating the first tank and the second tank to a temperature above a melting point of the one or more of cyclic monomers and oligomers including a cyclic group, for example between about 80°C to about 90°C and maintaining the first tank and the second tank under a nitrogen blanket.

[0028] In a still further aspect or embodiment, the method further includes the step of maintaining the mixing device at a temperature above a melting point of the one or more of cyclic monomers and oligomers including a cyclic group, for example between about 100°C and about 140°C.

[0029] In an additional aspect or embodiment, wherein the step of processing the plurality of continuous fibers includes drying the fibers at a temperature between about 70°C and about 100°C.

[0030] In a further aspect or embodiment, the method further includes the step of maintaining the packing and polymerization unit above a melting point of the one or more of cyclic monomers and oligomers including a cyclic group, for example at a temperature between about 140°C and about 180°C, and further including the step of performing the winding step at a temperature between about 140°C to about 180°C.

[0031] In yet another aspect or embodiment, wherein the assembly line further includes a winding chamber with the winding device located therein, and further including the step of one or more of a) maintaining the winding chamber under a nitrogen blanket and b) maintaining the winding chamber at a relative humidity of less than 15%, preferably less than 5% as measured by ASTM E337 (2024).

[0032] In a further aspect or embodiment, the method further includes the step of heating the winding chamber to a temperature between about 140°C to about 180°C.

[0033] In an additional aspect or embodiment, the method further includes the step of transferring the gas storage vessel after winding to an oven, and further including the step of maintaining the oven above a melting point of the one or more of cyclic monomers and oligomers including a cyclic group, for example at a temperature of about 140°C to about 200°C to further polymerize the one or more of the cyclic monomers and oligomers.

[0034] In a further aspect or embodiment, a controlled environment assembly line is disclosed, comprising a chamber having a controlled environment which has a relative humidity of less than 30%, preferably less than 20% as measured by ASTM E337 test standard (2024); an assembly line located within the chamber and comprising: a rack for holding a continuous fiber source including at least one continuous fiber, wherein the rack includes fiber guides adapted to combine continuous fibers from multiple spools and transfer them downstream in a process flow direction for further processing; a resin source including a resin composition, wherein the resin source includes a first tank adapted to hold a first feedstock comprising a first portion of a resin composition comprising one or more of cyclic monomers and oligomers including a cyclic group and an activator, wherein the resin source includes a second tank to hold a second feedstock comprising a second portion of resin composition comprising one or more of cyclicmonomers and oligomers including a cyclic group and a catalyst, wherein the resin source includes a mixing device that combines the first feedstock from the first tank and the second feedstock from the second tank, and wherein the resin source is adapted to maintain the resin composition under an inert gas blanket and at a temperature above a melting point of one the one or more cyclic monomers and oligomers including a cyclic group of the resin composition; an applicator device that is able to contact the continuous fiber with the resin composition to produce a wetted continuous fiber; and a winding device that receives the wetted continuous fiber produced by the applicator device.

[0035] In a further aspect or embodiment, the assembly line further includes a fiber spreader located downstream from the rack, wherein the fibers spreader is suitable for arranging the continuous fibers at a desired orientation and spacing between a plurality of continuous fibers.

[0036] In a still further aspect or embodiment, the assembly line further includes a moisture reduction unit located downstream from the rack, and fiber spreader when present, wherein the moisture reduction unit is adapted for reducing the moisture content of the continuous fibers.

[0037] In yet a further aspect or embodiment, the assembly line further includes a packing and polymerization unit located downstream from the applicator device, wherein the packing and polymerization unit includes a die having a channel that narrows in a downstream direction.

[0038] In a further aspect or embodiment, the assembly line further includes a heating device located downstream from the packing and polymerization unit which is adapted to apply heat to the resin wetted continuous fiber received from the packing and polymerization unit.

[0039] In an additional aspect or embodiment, the assembly line further includes a winding guide located downstream from the applicator device and upstream from the winding device, wherein the winding guide can traverse a travel path in order to aid in winding the resin wetted continuous fibers.

[0040] In a further aspect or embodiment, the winding device includes a winding chamber which is filled with an inert gas, and wherein the winding chamber is maintained at a relatively humidity of less than 15% as measured by ASTM E337 (2024).

[0041] In an additional aspect or embodiment, a gas storage vessel is disclosed, comprising: a liner having a hollow body with an internal volume and at least one aperture; and a pressure-resistant structural layer disposed on at least one portion of an outer surface of the liner, wherein the structural layer includes a continuous fiber thermoplastic composite material comprising a continuous fiber and a thermoplastic polymer in which the continuous fiber is present at a loading of at least 60% by weight, based on the total weight of thermoplastic polymer and continuous fiber in the structural layer, wherein the thermoplastic polymer is derived from a resin composition including one or more of a cyclic monomer or oligomer including a cyclic group, the resin composition having a viscosity less than 50 cP (mPa-s) or between 1 cP (mPa-s) and 50 cP (mPa-s), at the wetting and / or polymerization temperature of the cyclic monomer or oligomer as measured according to ISO 2555 (2024), and wherein the continuous fiber has a length of at least 100 meters.

[0042] In a further aspect or embodiment, the continuous fiber has a length of at least 1000 meters.

[0043] In still a further aspect or embodiment, the continuous fiber loading is at least 70%, 80% or 85% by weight.

[0044] In a further aspect or embodiment, the continuous fiber is wound and / or braided around at least one portion of the liner.

[0045] In a further aspect or embodiment, the continuous fiber is one or more of a glass fiber, an aramid fiber, a carbon fiber, a basalt fiber, an ultra-high molecular weight polyethylene fiber, a boron fiber, and a natural fiber.

[0046] In yet a further aspect or embodiment, thermoplastic polymer has a molecular weight (Mw) that ranges from about 500 to about 2,000,000 g / mol measured according to ASTM by gel permeation chromatography.

[0047] In another aspect or embodiment, the tank has a pressure rating of at least 1500 bars (150 mPa), 700 bars (70 mPa) or 350 bars (35 mPa).

[0048] In an additional aspect or embodiment, the cyclic monomer or oligomer includes an amide group.

[0049] In a further aspect or embodiment, a gas storage vessel, comprises: a pressureresistant structural layer including a continuous fiber thermoplastic composite material comprising a continuous fiber and a thermoplastic polymer in which the continuous fiber is present at a loading of at least 60% by weight, based on the total weight of thermoplastic polymer and continuous fiber in the structural layer, wherein the thermoplastic polymer is derived from a resin composition including one or more of a cyclic monomer or oligomer including a cyclic group, the resin composition having a viscosity less and 50 cP (mPa-s) or between 1 cP (mPa-s) and 50 cP (mPa-s), at the wetting and / or polymerization temperature of the cyclic monomer or oligomer as measured according to ISO 2555 (2024), wherein the continuous fiber has a length of at least 100 meters.

[0050] In an additional aspect or embodiment, the continuous fiber has a length of at least 1000 meters.

[0051] In a further aspect or embodiment, the continuous fiber loading is at least 70%, 80% or 85% by weight.

[0052] In yet a further aspect or embodiment, the continuous fiber is wound and / or braided around at least one portion of the liner.

[0053] In an additional aspect or embodiment, the continuous fiber is one or more of a glass fiber, an aramid fiber, a carbon fiber, a basalt fiber, an ultra-high molecular weight polyethylene fiber, a boron fiber, and a natural fiber.

[0054] In a further aspect or embodiment, the thermoplastic polymer has a molecular weight (Mw) that ranges from about 500 to about 2,000,000 g / mol measured according to ASTM by gel permeation chromatography.

[0055] In a still further aspect or embodiment, the tank has a pressure rating of at least 1500 bars (150 mPa), 700 bars (70 mPa) or 350 bars (35 mPa).

[0056] In yet another aspect or embodiment, the cyclic monomer or oligomer includes an amide group.

[0057] For the avoidance of doubt, it is understood that while various embodiments or aspects of the invention are described individually, it should be clear that two or more embodiments or aspects can be, and often times are, present in a single device or method according to the present invention.BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The invention will be better understood, and other features and advantages will become apparent by reading the detailed description of the invention, taken together with the drawings, wherein:

[0059] FIG. 1 illustrates a gas storage vessel according to one embodiment of the invention;

[0060] FIG. 2 is a schematic view of one embodiment of a manufacturing process for producing a gas storage vessel including structural layer with a continuous fiber thermoplastic composite material according to the invention; and

[0061] FIG. 3 is a process flow diagram describing the primary steps for producing a gas storage vessel of the invention.DETAILED DESCRIPTION OF THE INVENTION

[0062] The present invention includes a gas storage vessel comprising a pressure- resistant structural layer including a continuous fiber thermoplastic composite material wherein the continuous fiber is present at a relatively high loading by weight based on the weight of the thermoplastic polymer and continuous fiber in the structural layer. Methods for preparing gas storage vessels are described herein. Continuous fiber thermoplastic composite materials, methods of their preparation and an assembly line for producing the same are also detailed herein.

[0063] With reference to FIG. 1 , a gas storage vessel 10 is illustrated. Vessel 10 in some embodiments includes a liner 20 having a hollow body 22 with an internal volume 24 and at least one aperture 26. Vessel 10 includes a gas inlet 40 and a gas outlet 42, each preferably including a valve 44. Optionally, vessel 10 can have only one inlet / outlet valve.

[0064] A structural layer 50 including a continuous fiber thermoplastic composite material is disposed on at least a portion of an outer surface of the liner 20 when present. When liner 20 is not present, the internal volume 24 is within structural layer 50. Preferably, the structural layer 50 covers a substantial portion of the liner, for example greater than 80%, greater than 90% or higher. Preferably the structural layer covers substantially all of the liner 20.

[0065] FIG. 2 is a schematic illustration of one embodiment of a manufacturing process for producing a gas storage vessel including a continuous fiber thermoplastic composite material according to the invention. Process or assembly line 100 is shown located within a controlled environment 10 which maintains desired parameters of the atmosphere within the controlled environment. By way of non-limiting example, the controlled environment 10 can have the form of a room, housing or other enclosure in which the assembly line 100 is located. Parameters that can be managed within the controlled environment include relative humidity, temperature, and gas composition. Conditions within the controlled environment can be manipulated for example utilizing dehumidifiers and heating sources. Heating sources include, but are not limited to, furnaces, heated blowers, infrared heaters and ovens.

[0066] Gas composition of the controlled environment can vary within different stations of the assembly line 100 as desired by the user, such as further described herein.

[0067] Assembly line 100 includes a continuous fiber source 110 including at least one continuous fiber 102.

[0068] In a preferred embodiment process or assembly line 100 is equipped with a rack 112 having spools 114 of single fibers, tows or yarns of continuous fibers 102. In some embodiments the continuous fiber source 110 includes fiber guides 116 that combine continuous fibers from multiple spools 114 and transfer them downstream in the processflow direction for further processing. The process flow direction in FIG. 2 is generally from left to right, with for example, the continuous fiber source 110 being located upstream from the remaining stations and components thereof.

[0069] Fiber spreader 120 is located downstream from continuous fiber source 110 and receives at least one and preferably a plurality of continuous fibers 102. When a plurality of continuous fibers is fed to the fiber spreader 120, the latter arranges the continuous fibers at a desired orientation and spacing between the plurality of continuous fibers present. FIG. 2 illustrates a partial cross-sectional view of dry fibers having one embodiment of an orientation. In one embodiment the fiber spreader 120 separates and / or spreads the fibers relatively evenly in a sheet-like form, thereby exposing a larger amount of surface area, which is desirable for subsequent wetting with a resin composition.

[0070] The continuous fibers 102 are transferred from the fiber spreader 120 to a moisture reduction unit 130 which, when necessary, reduces the moisture content of the continuous fibers to a desired level. Moisture reduction can be accomplished utilizing a heating device present in the moisture reduction unit 130. Applying heat to the continuous fiber drives moisture therefrom. In order to accomplish moisture removal, temperature in the moisture reduction unit ranges from about 50°C to about 120°C, and preferably from about 70 to about 100°C. Temperatures that are too low do not remove enough moisture which can interfere with the catalyst utilized to drive polymerization of the one or more cyclic monomers and oligomers. Temperatures which are too high may affect the integrity of the fibers and / or cause premature polymerization when contacted with the resin composition.

[0071] The assembly line 100 further includes an applicator device 150 for contacting the continuous fibers and the resin composition. The applicator device includes an injection and impregnation unit 152 for example as shown in FIG. 2. The continuous fibers and the resin composition contact each other in the applicator device generally by applying the resin composition to the continuous fibers as they travel through the injection and impregnation unit 152 whereby the continuous fibers become wetted with the resin composition. In one embodiment a nozzle is utilized to inject the resin composition suchthat it contacts the continuous fibers adjacent the outlet of the nozzle. The resin tanks, dosing pumps, mixing head / injection unit, applicator, die, and the take-off system are commercially available from suppliers such as KraussMaffei Technologies, GmbH., Pultrex Ltd, and Liberty Pultrusion, etc.

[0072] Resin source 140 houses the resin composition prior to the latter being contacted with the continuous fibers. In a preferred embodiment, for example as shown in FIG. 2, the resin source includes a first tank 142 which holds a first feedstock comprising a first portion of resin composition comprising one or more of cyclic monomers and oligomers including a cyclic group and an activator. The resin source 140 also includes a second tank 144 with a second feedstock comprising a second portion of resin composition comprising one or more of cyclic monomers and oligomers including a cyclic group and a catalyst. The activator and catalyst are maintained separately in order to prevent premature polymerization of the resin composition. The first feedstock and second feedstock are combined in a mixing device 146 and subsequently applied to the continuous fibers through a nozzle operatively connected to the mixing device 146 in the applicator device 150.

[0073] In an important aspect of the invention, the resin composition in the resin source 140 is maintained in an inert environment in order to keep moisture exposure as low as possible, with at least the catalyst being sensitive to water which will kill or otherwise reduce effectiveness of the catalyst. The resin composition comprising one or more of cyclic monomers and oligomers tends to absorb moisture in the ambient air quickly. Thus, both first tank 142 and second tank 144 are maintained under an inert gas blanket to counter the effects of ambient air on the resin composition. The blanketing process controls the atmosphere above the resin composition, which is a liquid. The preferred inert gas is nitrogen, although other gases may be utilized, for example any of the noble gases.

[0074] In order to contact or wet the continuous fibers with the resin composition, the resin composition is maintained at a temperature above the melting point of the one or more cyclic monomers and oligomers including a cyclic group. Thus, it should be readily understood by one of ordinary skill in the art that the temperature of the resin compositionin both the first tank 142 and second tank 144 will vary depending upon monomer or oligomer choice.

[0075] That said, in a preferred embodiment for example when caprolactam is utilized as monomer, the resin composition is maintained at a temperature between from about 70°C and about 100°C and preferably from about 80°C to about 90°C in the first tank 142 and second tank 144. The temperature of the resin composition is increased after the feedstocks are combined in the mixing device 146 before being injected within the applicator device 150. Suitable temperatures range from about 80°C to about 160°C and preferably are about 100°C to about 140°C.

[0076] The assembly line 100 further includes a packing and polymerization unit in the form of a die 160 located downstream from the applicator device 150. Applicator and the die can be combined and connected together to form one continuous unit. In the packing and polymerization unit, the wetted fibers are pulled through a narrowing channel while being heated so that polymerization of the resin composition takes place. For example, when caprolactam is utilized as monomer, the temperature ranges between about 120°C and about 200°C and preferably about 140°C to about 180°C. The cross-sectional geometry determines the shape of the extrude exiting the die. For continuous winding of pressure tanks, a ribbon shape is preferred.

[0077] As the wetted continuous fiber continues downstream in the process flow direction from the packing and polymerization unit 160, heat is applied to the resin wetted continuous fibers so that polymerization continues. Suitable temperatures vary depending upon the monomer and / or oligomer utilized and include those listed for the packing and polymerization unit described herein above. Generally, any suitable heating devices can be utilized, for example heater device 170, which can be an infrared heater or hot air blower or the like.

[0078] At least one and preferably multiple strands of the composite fibers 110 are utilized.

[0079] The one or more resin wetted continuous fibers 104 contacted with the resin composition are transferred to a winding guide 180 including a heating device. The guide180 can traverse a travel path 182 in order to aid in winding the resin wetted continuous fibers into a gas storage vessel or part of a gas storage vessel. The resin wetted continuous fibers 104 are wound utilizing a winding device 200 onto a form 190 such as a liner that becomes part of the gas storage vessel or core such as a mandrel that can be removed from the continuous fiber thermoplastic composite after it is wound into the form of a gas storage vessel and polymerized. The travel path 182 as illustrated is generally lateral to the process flow direction shown in order to aid winding the continuous fiber thermoplastic composite material onto a form 190.

[0080] In a preferred embodiment the winding device 200 includes a winding chamber 210 which can be, for example, a housing or enclosure which can be filled with an inert gas such as described above. Nitrogen is preferably utilized in one embodiment. Filling the winding chamber 210 with an inert gas or nitrogen blanket allows the relative humidity to be maintained below a desired threshold. In the winding chamber 210, it is desirable to maintain a relative humidity of less than 15% and preferably less than 5% as measured by ASTM E337 (2024).

[0081] In order to further polymerize the resin composition, the winding device 200 is also provided with one or more heating devices 230 which can be used to heat the resin wetted continuous fibers in the winding chamber to a suitable temperature, such as about 140°C to about 180°C when caprolactam is utilized as monomer in the resin composition. The heating device may significantly reduce the relative humidity in the winding chamber to a point that an inert gas blanket is not needed. This can be determined by a person skilled in the art.

[0082] In some embodiments, the assembly line 100 winding device 200 includes a vessel manipulating device 220, such as one or more robotic arms, that is able to move the form 190 in one or more of an X, Y and Z direction to aid in forming the gas storage vessel 300. The tank manipulating device 220 is also able to rotate the form 190 in preferred embodiments.

[0083] The heating devices provided with guide 180 and winding device 200 aid in further polymerizing the one or more cyclic monomers and / or oligomers including a cyclic groupof the resin composition contacted with the continuous fibers 102. Suitable temperatures depend on factors such as monomers and oligomers utilized, as well as desired degree of polymerization prior to winding on form 142. Multiple heating devices can be used in different locations to enhance polymerization before, during and after the fiber winding process.

[0084] Optionally the formed pressure vessel can be further heated after winding in an autoclave oven 300 for a period of time to strengthen the mechanical integrity of the pressure vessel. It is preferred to keep the vessel rotating during the autoclave heating process to prevent unevenness of resin distribution and temperature distribution. The residence time in the autoclave oven depends on the resin chemistry and the desired level of polymerization. It is preferred to have the residence time in the autoclave oven for less than 3 hours, more preferred less than 2 hours, even more preferred less than 1 hour, and most preferred less than 30 minutes. Temperatures in the autoclave oven 300 range generally from about 100°C to about 300°C, preferably from about 130°C to about 260°C, and more preferably from 140°C to about 200°C when caprolactam is utilized as monomer in the resin composition. In a preferred embodiment, the autoclave oven is maintained under an inert gas blanket, for example nitrogen in order to minimize the effects of moisture. Optionally autoclave can be pressurized to improve contacts, reduce voids, and to further enhance polymerization in the thermoplastic composite.

[0085] In some embodiments, the process line includes multiple winding devices. The use of multiple winding devices allows for braiding of the continuous fiber thermoplastic material, which enhances strength of the structural layer.

[0086] Methods for producing gas storage vessels utilizing the assembly line 100 according to the invention are further described herein below.

[0087] Gas Storage Vessel

[0088] The gas storage vessel 10 of the invention exhibits desirable structural integrity which allows it to be employed as a hydrogen storage vessel or natural gas storage vessel, or a vessel for other gases as desired by the end user. The gas storage vessel has an internal volume generally disposed within a liner 20 having a hollow body, whenpresent, or within the structural layer 50 when a liner 20 is not present. The liner and structural layer 50 have at least one aperture. Two apertures are shown in FIG. 1 in the form of inlet 40 and outlet 42.

[0089] In a preferred embodiment, the gas storage vessel has a cylindrical shape, such as illustrated, with the one or more outlets being placed or located at the ends of the cylinder. The shape of the vessel and thus the shape of the liner, when present, and structural layer disposed on the liner are generally determined by end use. When cylindrical, the gas storage vessel can have a diameter that ranges between 10 cm and 2 m, preferably between 30 cm and 1 m, and more preferably between 35 and 65 cm. The length of the gas storage vessel also depends upon ends uses thereof. Example lengths ranges between 50 cm and 10 m. Generally longer lengths are usually employed for bulk gas transport.

[0090] Operating temperatures of the gas storage vessel vary depending upon end use as well. When utilized for hydrogen storage, the vessel generally has an operating temperature between -60°C to 300°C, more preferably below 200°C, even more preferably below 100°C, and most preferably below 75°C.

[0091] Liner

[0092] A liner 20 is present in one embodiment of the present invention as a form or foundation for the structural layer 50. The liner may also possess properties which contribute to the gas tightness of the storage vessel.

[0093] The liner is preferably formed from a thermoplastic material that can be recycled once storage vessel has reached its end life. Non limiting examples of suitable liner materials include metal; polyolefins such as polypropylene and polyethylene; polystyrene; polyvinyl chloride; ethylene vinyl alcohol; polyamide; polycarbonate; and polyesters such as polyethylene terephthalate and other suitable thermoplastic polymers. The polymeric liner can be produced through injection molding, blow molding and rotational molding and other suitable processes.

[0094] Liner thickness varies depending upon the gas diffusion barrier required by the particular gas being stored within the gas storage vessel and its mechanical integrity needed during winding and polymerization.

[0095] In other embodiments of the invention, the structural layer 50 including the continuous fiber thermoplastic composite material is formed from the polymerized resin wetted continuous fibers on a removable core that is taken out of the gas storage vessel prior to being put into service, and preferably after the resin wetted continuous fibers have been formed into the continuous fiber thermoplastic composite material of the structural layer. In a preferred embodiment, the continuous fibers contacted with the composition comprising one or more of cyclic monomers and oligomers with a cyclic group which are thermoplastic polymer precursors are wound onto a supporting removable core, such as a mandrel. After polymerization of the monomers or oligomers, the core is taken out.

[0096] Structural Layer

[0097] The structural layer 50 includes a continuous fiber thermoplastic composite material comprising at least a continuous fiber and a thermoplastic polymer which is derived from polymerization of the resin wetted continuous fibers.

[0098] Continuous Fiber

[0099] The structural layer 50 according to the invention includes at least one continuous fiber. Continuous fibers are also known in the art as endless fibers, elongated fibers or the like. For purposes of the invention, the term “continuous fiber” as utilized herein defines a fiber having a length of at least 10 meters, preferably at least 100 meters, more preferably at least 1 ,000 meters, and most preferably at least 10,000 meters. In preferred embodiments the continuous fibers of the invention have a length that ranges between 10 meters and 10,000 meters, and preferably between 100 meters and 1 ,000 meters. The L / D ratio of the fiber is preferably higher than 500.

[0100] The continuous fiber of the present invention may comprise a single fiber, filament and individual strand, or a bundle of multiple strands of continuous fibers and filaments. Bundles of fibers are often considered yams. Carbon fibers are typically made with 1 to 400,000 thousand (1 k to 400k) individual fibers oriented in the same direction and tightlypacked into one tow and wound onto a spool. Both small and large tows of carbon fiber can be used to make pressure vessels of the invention with small tows being preferred for their better mechanical performance. Multiple individual single strands from multiple spools of single fibers, filaments or tows can be individually contacted or wetted with the resin composition comprising one or more of cyclic monomers and oligomers with a cyclic group that are thermoplastic polymer precursors before being wound onto the liner or core together as a bundle or prepreg. It is preferred to have substantially all surface areas of individual fibers wetted in order to increase the strength and physical integrity of the fiber composite.

[0101] The continuous fiber can be cylindrical in shape or non-cylindrical. The cross section of the fiber can be circular or non-circular such as ellipsoidal, triangular, square, rectangular, pentagonal, hexagonal, trapezoidal, parallelogram and other irregular and non-sym metrical shapes.

[0102] The continuous fiber of the present invention may be formed of materials that include, but are not limited to, glass fibers, aramid fibers, carbon fibers, natural fibers, a basalt fiber, ultra-high molecular weight polyethylene, and a boron fiber and combinations thereof.

[0103] In some embodiments, the continuous fiber may be provided with a coating on at least a portion thereof in order to improve compatibility and / or adhesion between the continuous fiber and the cyclic monomers and oligomers with a cyclic group that are thermoplastic polymer precursors before being wound onto the liner or core together as a bundle or prepreg. Suitable coatings are known to those of ordinary skill in the art.

[0104] In an important aspect of the present invention, the continuous fiber is present in the structural layer in a sufficient amount to provide pressure integrity to the gas storage vessel.

[0105] Due to the composition of the structural layer, the continuous fibers are present in an amount of at least 60% by weight, 70% by weight, at least 80% by weight or at least 85% by weight based on the total weight of the continuous fiber and thermoplastic polymer in the structural layer.

[0106] Polymerizable Monomers and Oligomers

[0107] The finished structural layer 50 includes at least one polymer derived from plurality of a) monomers having a cyclic group and b) oligomers including a cyclic group. The monomers and / or oligomers are used to form a resin composition or polymer precursor composition that has a low viscosity at the processing and / or wetting temperature. Different resin compositions require different wetting and polymerization temperatures. A person skilled in the art can find the best or optimal wetting and polymerization temperatures for different cyclic monomers or oligomers with or without polymerization catalysts and / or activators. That said, the viscosity of the resin system has a viscosity less than 50 cP (mPa-s) or between 1 cP (mPa-s) and 50 cP (mPa-s), preferably between 3 cP (mPa-s) and 30 cP (mPa-s) and more preferably between 5 cP (mPa-s) and 25 cP (mPa-s) at the wetting and / or polymerization temperature of the cyclic monomer or oligomer as measured according to ISO 2555 (2024). Examples of the viscosity of some of the cyclic monomers or oligomers are listed in Table 1 .Table 1

[0108] Examples of cyclic monomer or oligomer systems are AP-Nylon and NYRIM systems from Bruggemann. AP-Nylon is a reactive system with cyclic monomer being caprolactam with very low viscosity above its melting point (79°C). Activator and catalyst come in two separate packages. The advantage of such a system is its low wetting and polymerization temperature (typically from 100 to 160°C). NYRIM system is also caprolactam based but with different amount of elastomer component built into its backbone to improve its impact resistance.

[0109] The resin composition including the specific monomers and / or oligomers is contacted with, imbibes, or wets the continuous fiber. Thereafter, polymerization is performed, with or without a suitable catalyst and activator. The low viscosity of the resin composition allows for the relatively high loading of fibers compared to the weight of the polymer produced resin composition. After polymerization, the resulting polymer has a relatively high number average molecular weight (Mn) that ranges generally from about 500 to about 2,000,000, preferably from 2000 to about 500,000, and more preferably from 10,000 to 100,000 g / mol as measured according to by gel permeation chromatography (GPC).

[0110] The number average molecular weight and distribution of any type of polymer described in this application are measured by gel permeation chromatography (GPC). The polymer is dissolved in a suitable solvent, such as THF, (typically 0.001 -0.010 wt.%), and an appropriate quantity is injected into a GPC device. One suitable GPC device is available from Waters of Milford, MA as a Waters Breeze Dual Pump LC. The GPC analysis is performed at an appropriate elution rate (1 to 10 mL / min). The molecular weight distribution is characterized by the signals from UV and refractive index detectors, and number average molecular weights are calculated using a calibration curve generated from a series of narrow molecular weight distribution polystyrenes with peak molecular weights of 500 to 1 ,000,000 as standard.

[0111] Examples of suitable monomers and oligomers include, but are not limited to, caprolactam, lactone, caprolactone (i.e. cyclic poly(caprolactone) oligomer), a cyclic polyester oligomer, a cyclic polyolefin oligomer, a cyclic poly(phenylene oxide) oligomer, a cyclic poly(phenylene sulfide) oligomer, a cyclic polyphenylsulfone oligomer, a cyclic polyetherimide oligomer, and / or co-oligomers thereof. In some embodiments, the cyclic oligomer contains or is a macrocyclic polyester oligomer, for example, a macrocyclic poly(butylene terephthalate) oligomer, a macrocyclic polyethylene terephthalate) oligomer, and / or co-oligomers thereof. Combinations of the monomers and oligomers may be utilized in various embodiments.

[0112] As used herein, a "macrocyclic polyester oligomer" (MPO) is understood to mean a macrocyclic oligomer containing structural repeat units having an esterfunctionality. A macrocyclic polyester oligomer typically refers to multiple molecules of one specific repeat unit formula. However, a macrocyclic polyester oligomer also may include multiple molecules of different or mixed formulae having varying numbers of the same or different structural repeat units. In addition, a macrocyclic polyester oligomer may be a co-polyester or multi-component polyester oligomer, i.e., an oligomer having two or more different structural repeat units having ester functionality within one cyclic molecule.

[0113] The thermoplastic polymer derived from cyclic monomers and / or oligomers offers processing advantages of a thermoset, having low viscosity above the monomer or oligomer’s melting point which is good for fiber wetting, while retaining material properties of a thermoplastic once polymerized, enabling the production of a robust thermoplastic structural layer including the continuous fiber.

[0114] The resulting continuous fiber thermoplastic composite has very high strength, in addition to excellent toughness due to the high molecular weight of the thermoplastic resin. In addition, the structural layer, and preferably gas storage vessel, is fully recyclable as the thermoplastic resin can be melted down and re-used.

[0115] Other Components

[0116] The structural layer may optionally include other components that impart beneficial properties to the gas storage tank formed therewith. Example components include, but are not limited to, heat stabilizers, flame retardants, colorants, lubricants, UV stabilizers, impact modifiers, nucleating agents, antioxidants, activators, and catalysts.

[0117] Polymerization catalysts employed in certain embodiments of the invention are capable of catalyzing the polymerization of the one or more of cyclic monomers and oligomers with a cyclic group. Organotin and organotitanate compounds are preferred catalysts, although other catalysts and activators may be used as desired. When caprolactam is used as a monomer, isocyanate activators including pyrrolidone-free versions, and sodium or magnesium-based catalysts can be used.

[0118] Depending upon the properties desired, the amounts of each optional ingredient can vary.

[0119] Method for Producing the Gas Storage Vessel and Structural Layer Thereof

[0120] The method for producing a gas storage vessel includes the steps of obtaining a continuous fiber having a desired length and contacting the continuous fiber with a resin composition comprising one or more cyclic monomers and oligomers including a cyclic group which are thermoplastic polymer precursors thereby forming a resin wetted continuous fiber which is subsequently polymerized to form a continuous fiber thermoplastic composite material. In one embodiment, the contacting of the continuous fiber with the monomers and / or oligomers takes place in the applicator device. Multiple continuous fibers are preferably unwound from a spool or creel and of the continuous fiber source and fed to the fiber spreader which arranges the plurality of continuous fibers at a desired orientation and spacing between the plurality of continuous fibers. The plurality of continuous fibers are processed in a moisture reduction unit so that a moisture content thereof is at or below 0.1%, preferably below 0.01 % as measured using a moisture analyzer with a proper detection limit prior to contacting the plurality of continuous fibers with the resin composition using the applicator device. Spools of continuous fibers can be pre-dried in a vacuum oven or a heat oven with a desiccant bed at temperatures about 70°C to 110°C, preferably between 80°C and 100°C.

[0121] The resin system or resin composition is maintained at a temperature at, or preferably above, the melting point of the one or more cyclic monomers and oligomers with a cyclic group. Accordingly, temperature of the resin composition will vary depending on particular monomers and / or oligomers selected for use. For example, Cyclic CBT-100 resin has a much higher melting point, therefore, the resin composition should be maintained at temperatures above 180°C to keep it in the liquid form.

[0122] The resin wetted continuous fibers are transferred from the applicator device to a packing and polymerization unit located downstream therefrom where polymerization of the resin composition takes place.

[0123] Thereafter, the resin wetted continuous fiber are passed through a heating device to a guide and subsequently to a winding device wherein the resin wetted continuous fibers are applied to the liner. The plurality of resin wetted continuous fibers create atleast a portion of the structural layer of the gas storage vessel or other article. Preferably the composite material is wound around the liner so that a desired portion thereof is covered. As described herein, the winding can be, but is not limited to, a circumferential winding, a longitudinal winding, a spiral winding, a lateral winding or combinations thereof. During winding or once the desired configuration of composite material on the liner has been achieved, the monomers and / or oligomers are polymerized. Polymerization temperature depends upon the monomers utilized. That said, polymerization temperatures generally range from about 50°C to about 300°C, preferably from about 100°C to about 250°C. When caprolactam is used as a monomer the polymerization temperatures typically range from 100°C to 200°C, and more preferably from 120°C to 180°C. Multiple heaters can be used in different locations to enhance polymerization before, during and after the fiber winding process.

[0124] Optionally the formed pressure vessel can be further heated after winding in an autoclave oven for a period of time to strengthen the mechanical integrity of the pressure vessel. It is preferred to keep the vessel rotating during the autoclave heating process to prevent unevenness of resin distribution and temperature distribution. The residence time in the autoclave oven depends on the resin chemistry and the desired level of polymerization. It is preferred to have the residence time in the autoclave oven for less than 3 hours, more preferred less than 2 hours, even more preferred less than 1 hour, and most preferred less than 30 minutes.

[0125] In view of the above, FIG. 3 presents a process flow diagram describing the primary steps for producing a gas storage vessel of the invention.

[0126] In step 500, a plurality of continuous fibers are arranged utilizing a fiber spreader.

[0127] In step 510, the continuous fibers are processed to reduce moisture content.

[0128] In step 520, the fibers are transferred to an applicator device and contacted with the resin composition.

[0129] In step 530, the resin wetted continuous fibers are packed and begin to undergo polymerization.

[0130] In step 540, the resin wetted continuous fibers are wound onto a core or liner and heated to form a gas storage vessel.

[0131] In step 550, post treatment of the pressure tank is optionally performed if needed to enhance polymerization and reduce residual stress.

[0132] Step 560 involves quality inspection and testing of the produced gas storage vessel.

[0133] For the avoidance of doubt, the compositions and methods of the present invention encompass all possible combinations of the components, including various ranges of said components, disclosed herein. It is further noted that the term ‘comprising’ does not exclude the presence of other elements. However, it is also to be understood that a description of a product comprising certain components also discloses a product consisting of these components. Similarly, it is also to be understood that a description on a process comprising certain steps also discloses a process consisting of these steps.

[0134] In accordance with the patent statutes, the best mode and preferred embodiment have been set forth; the scope of the invention is not limited thereto, but rather by the scope of the attached claims.

Claims

WHAT IS CLAIMED IS:1 . A method for producing a gas storage vessel, comprising the steps of: obtaining a continuous fiber processing assembly line located in a controlled environment which has a relative humidity of less than 30%, preferably less than 20% as measured by ASTM E337 test standard (2024); wherein the assembly line comprises: a continuous fiber source including at least one continuous fiber; a resin source including a resin composition, wherein the resin composition includes one or more of cyclic monomers and oligomers including a cyclic group; an applicator device for contacting the continuous fiber and the resin composition; and a winding device that receives resin wetted continuous fiber produced by the applicator device; contacting a portion of the at least one, and preferably substantially all, continuous fiber with the resin composition using the applicator device to produce a resin wetted continuous fiber; transferring the resin wetted continuous fiber to a winding device and using the winding device to form at least a portion of a structural layer of a gas storage vessel with the resin wetted continuous fiber; polymerizing the resin composition at a time after it is contacted with the continuous fiber to form a thermoplastic polymer, wherein the resin wetted continuous fiber or the subsequent continuous fiber thermoplastic composite has a fiber loading of at least 60% by weight, based on the total weight of the thermoplastic polymer and continuous fiber in the structural layer.

2. The method according to claim 1 , wherein the continuous fiber source includes a plurality of continuous fibers, wherein the continuous fibers are one or more of a glass fiber, an aramid fiber, a carbon fiber, a basalt fiber, an ultra-high molecular weight polyethylene fiber, a boron fiber, and a natural fiber, andfurther including the step of feeding the plurality of continuous fibers to a fiber spreader which arranges the plurality of continuous fibers at a desired orientation and spacing between the plurality of continuous fibers.

3. The method according to claim 2, further including the step of processing the plurality of continuous fibers in a moisture reduction unit so that a moisture content thereof is at or below 0.1 %, preferably below 0.01 % as measured using a moisture analyzer with a proper detection limit prior to contacting the plurality of continuous fibers with the resin composition using the applicator device.

4. The method according to claim 3, wherein the assembly line further incudes a packing and polymerization unit located downstream from the applicator device, and further including the step of polymerizing the resin composition including the one or more of the cyclic monomers and oligomers in the packing and polymerization unit in the form of a die.

5. The method according to any of claims 1-4, wherein the resin source includes a first tank with a first feedstock comprising the resin composition and an activator, wherein the resin source includes a second tank with a second feedstock comprising the resin composition and a catalyst, wherein the resin source includes a mixing device, further including the step of combining the first feedstock and the second feedstock with the mixing device to form a mixed resin composition, and further including the step of feeding the mixed resin composition to the applicator device.

6. The method according to claim 5, further including the step of using the applicator device to contact the plurality of continuous fibers with the mixed resin composition to form a plurality of resin wetted continuous fibers.

7. The method according to claim 6, further including the step of passing the resin wetted continuous fibers through a heating device to a guide and then subsequently to the winding device.

8. The method according to claim 7, further including the step of using the winding device to apply the plurality of resin wetted continuous fibers to a form and creating at least a portion of the structural layer of the gas storage vessel.

9. The method according to any of claims 5-8, further including the steps of heating the first tank and the second tank to a temperature above a melting point of the one or more of cyclic monomers and oligomers including a cyclic group, for example between about 80°C to about 90°C, and maintaining the first tank and the second tank under a nitrogen blanket.

10. The method according to any of claims 5-9, further including the step of maintaining the mixing device at a temperature above a melting point of the one or more of cyclic monomers and oligomers including a cyclic group, for example between about 100°C and about 140°C.

11. The method according to claim 3, wherein the step of processing the plurality of continuous fibers includes drying the fibers at a temperature between about 70°C and about 100°C.

12. The method according to claim 4, further including the step of maintaining the packing and polymerization unit above a melting point of the one or more of cyclic monomers and oligomers including a cyclic group, for example at a temperature between about 140°C and about 180°C, and further including the step of performing the winding step at a temperature between about 140°C to about 180°C.

13. The method according to any of claims 1 -12, wherein the assembly line further includes a winding chamber with the winding device located therein, and further includingthe step of one or more of a ) maintaining the winding chamber under a nitrogen blanket and b) maintaining the winding chamber at a relative humidity of less than 15%, preferably less than 5% as measured by ASTM E337.

14. The method according to claim 13, further including the step of heating the winding chamber to a temperature between about 140°C to about 180°C.

15. The method according to claim 14, further including the step of transferring the gas storage vessel after winding to an oven, and further including the step of maintaining the oven above a melting point of the one or more of cyclic monomers and oligomers including a cyclic group, for example at a temperature of about 140°C to about 200°C to further polymerize the one or more of the cyclic monomers and oligomers.

16. A controlled environment assembly line, comprising: a chamber having a controlled environment which has a relative humidity of less than 30%, preferably less than 20% as measured by ASTM E337 test standard; an assembly line located within the chamber and comprising: a rack for holding a continuous fiber source including at least one continuous fiber, wherein the rack includes fiber guides adapted to combine continuous fibers from multiple spools and transfer them downstream in a process flow direction for further processing; a resin source including a resin composition, wherein the resin source includes a first tank adapted to hold a first feedstock comprising a first portion of a resin composition comprising one or more of cyclic monomers and oligomers including a cyclic group and an activator, wherein the resin source includes a second tank to hold a second feedstock comprising a second portion of resin composition comprising one or more of cyclic monomers and oligomers including a cyclic group and a catalyst, wherein the resin source includes a mixing device that combines the first feedstock from the first tank and the second feedstock from the second tank, and wherein the resin source is adapted to maintain the resin composition under an inert gas blanket and at a temperature above a melting point of one or more cyclic monomers and oligomers including a cyclic group of the resin composition;an applicator device that is able to contact the continuous fiber with the resin composition to produce a wetted continuous fiber; and a winding device that receives the wetted continuous fiber produced by the applicator device.

17. The assembly line according to claim 16, further including a fiber spreader located downstream from the rack, wherein the fibers spreader is suitable for arranging the continuous fibers at a desired orientation and spacing between a plurality of continuous fibers.

18. The assembly line according to any of claims 16-17, further including a moisture reduction unit located downstream from the rack, and fiber spreader when present, wherein the moisture reduction unit is adapted for reducing the moisture content of the continuous fibers.

19. The assembly line according to any of the prior claims, further including a packing and polymerization unit located downstream from the applicator device, wherein the packing and polymerization unit includes a die having a channel that narrows in a downstream direction.

20. The assembly line according to claim 19, further including a heating device located downstream from the packing and polymerization unit which is adapted to apply heat to the resin wetted continuous fiber received from the packing and polymerization unit.21 . The assembly line according to any of claims 16-20, further including a winding guide located downstream from the applicator device and upstream from the winding device, wherein the winding guide can traverse a travel path in order to aid in winding the resin wetted continuous fibers.

22. The assembly line according to any of claims 16-21 , wherein the winding device includes a winding chamber which is filled with an inert gas, and wherein the winding chamber is maintained at a relatively humidity of less than 15% as measured by ASTM E337.

23. A gas storage vessel, comprising: a liner having a hollow body with an internal volume and at least one aperture; and a pressure-resistant structural layer disposed on at least one portion of an outer surface of the liner, wherein the structural layer includes a continuous fiber thermoplastic composite material comprising a continuous fiber and a thermoplastic polymer in which the continuous fiber is present at a loading of at least 60% by weight, based on the total weight of thermoplastic polymer and continuous fiber in the structural layer, wherein the thermoplastic polymer is derived from a resin composition including one or more of a cyclic monomer or oligomer including a cyclic group, the resin composition having a viscosity less than 50 cP (mPa-s) or between 1 cP (mPa-s) and 50 cP (mPa-s), at the wetting and / or polymerization temperature of the cyclic monomer or oligomer as measured according to ISO 2555, and wherein the continuous fiber has a length of at least 100 meters.

24. The vessel according to claim 23, wherein the continuous fiber has a length of at least 1000 meters.

25. The vessel according to claim 23 or claim 24, wherein the continuous fiber loading is at least 70%, 80% or 85% by weight.

26. The vessel according to any of claims 23 to 25, wherein the continuous fiber is wound and / or braided around at least one portion of the liner.

27. The vessel according to any of claims 23 to 26, wherein the continuous fiber is one or more of a glass fiber, an aramid fiber, a carbon fiber, a basalt fiber, an ultra-high molecular weight polyethylene fiber, a boron fiber, and a natural fiber.

28. The vessel according to any of claims 23 to 27, wherein the thermoplastic polymer has a molecular weight (Mw) that ranges from about 500 to about 2,000,000 g / mol measured according to ASTM by gel permeation chromatography.

29. The vessel according to any of claims 23 to 28, wherein the tank has a pressure rating of at least 1500 bars (150 mPa), 700 bars (70 mPa) or 350 bars (35 mPa).

30. The vessel according to any of claims 23 to 29, wherein the cyclic monomer or oligomer includes an amide group.31 . A gas storage vessel, comprising: a pressure-resistant structural layer including a continuous fiber thermoplastic composite material comprising a continuous fiber and a thermoplastic polymer in which the continuous fiber is present at a loading of at least 60% by weight, based on the total weight of thermoplastic polymer and continuous fiber in the structural layer, wherein the thermoplastic polymer is derived from a resin composition including one or more of a cyclic monomer or oligomer including a cyclic group, the resin composition having a viscosity less than 50 cP (mPa-s) or between 1 cP (mPa-s) and 50 cP (mPa-s), at the wetting and / or polymerization temperature of the cyclic monomer or oligomer as measured according to ISO 2555, wherein the continuous fiber has a length of at least 100 meters.

32. The vessel according to claim 31 , where the continuous fiber has a length of at least 1000 meters.

33. The vessel according to claim 31 or claim 32, wherein the continuous fiber loading is at least 70%, 80% or 85% by weight.

34. The vessel according to any of claims 31 to 33, wherein the continuous fiber is wound and / or braided around at least one portion of the liner.

35. The vessel according to any of claims 31 to 34, wherein the continuous fiber is one or more of a glass fiber, an aramid fiber, a carbon fiber, a basalt fiber, an ultra-high molecular weight polyethylene fiber, a boron fiber, and a natural fiber.

36. The vessel according to any of claims 31 to 35, wherein the thermoplastic polymer has a molecular weight (Mw) that ranges from about 500 to about 2,000,000 g / mol measured according to ASTM by gel permeation chromatography.

37. The vessel according to any of claims 31 to 36, wherein the tank has a pressure rating of at least 1500 bars (150 mPa), 700 bars (70 mPa) or 350 bars (35 mPa).

38. The vessel according to any of claims 31 to 37, wherein the cyclic monomer or oligomer includes an amide group.

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