Hollow Rotomolded Products

Abstract

1. A hollow rotomolded product having an interior wall defining an interior of the product and an integrally formed structure with the interior wall, the integrally formed structure projecting away from the interior of the product, the product being formed from a first layer comprising one or more thermoplastic polymers and a second layer comprising one or more fibrous materials.

Description

[Technical Field]

[0001] The present invention relates generally to rotationally molded (rotomolded) products. Specifically, embodiments of the present invention relate to hollow composite containers having at least a thermoplastic layer and a fibrous layer. Aspects of the present invention also relate to the manufacture of containers utilizing a rotational molding process. The containers may find use in the storage and transport of powders, liquids, gases, and cryogenic materials, particularly hazardous materials. [Background technology]

[0002] Tanks are widely used for the transportation of materials such as liquids, gases, powders, etc., both hazardous and non-hazardous. For the transportation of hazardous materials, tanks must meet many local and international regulations.

[0003] Tanks for the transport of hazardous materials are generally constructed from metal to provide structural strength and are lined with a resilient liner to protect the metal from the corrosive properties of the tank contents.

[0004] However, lined metal tanks have many disadvantages, including the excessive weight of the tank, which increases transportation costs, and the possibility that the liner material may deteriorate or become detached from the interior wall of the metal tank over time due to contact with the tank contents, requiring repair or replacement of the liner.

[0005] Additionally, most tanks require nozzles for filling, draining, and / or monitoring purposes. Conventionally, the nozzles are integrated into the tank by drilling holes in suitable locations on the tank and welding or otherwise clamping on prefabricated nozzles.

[0006] It would be desirable to provide an improved tank that overcomes or ameliorates one or more of the above-mentioned shortcomings or problems of the prior art, or at least provides a useful alternative option.

[0007] The reference to any prior art herein is not an admission or suggestion that this prior art forms part of the common general knowledge in any jurisdiction, or that this prior art would be understood by, considered relevant, and / or could reasonably be expected to be combined with other pieces of prior art by a person skilled in the art. Summary of the Invention

[0008] In a first aspect, the present invention provides a hollow rotomolded product having an interior wall defining an interior of the product and a structure integrally formed with the interior wall, the integrally formed structure projecting away from the interior of the product, the product being formed from a first layer comprising one or more thermoplastic polymers and a second layer comprising one or more fibrous materials.

[0009] Preferably, one or more fibrous materials are at least partially infiltrated with one or more thermoplastic polymers. In such an embodiment, an advantageous multilayer structure is produced, comprising a substantially thermoplastic inner / first layer together with a substantially fibrous second layer. The fibrous second layer can function as a suitable tie layer adapted to allow additional layers to be formed therewith. The thermoplastic inner layer can function as a barrier layer that is substantially impermeable to materials that contact the interior of the product. Furthermore, the integrally formed structure of the product is seamlessly integrated into the product having this same multilayer structure. Therefore, there are no welds or bond lines between the product and the integrally formed structure.

[0010] The rotomolded product when having only the first and second layers may be referred to herein as a thermoplastic polymer / fiber material composite (or the like).

[0011] In an embodiment, the structure is configured to allow fluid communication between the interior of the product and the environment external to the product. Preferably, the structure includes one or more nozzles. Advantageously, the or each nozzle is seamlessly integrated into the product having the same multi-layer structure. The or each nozzle may form one or more nozzles of the product, respectively. In an alternative embodiment, the or each nozzle is configured to receive one or more component parts that form the respective one or more nozzles of the product. In such an embodiment, the or each nozzle may facilitate attachment of the one or more component parts to form the respective nozzles of the product.

[0012] The or each nozzle may include a nozzle body having a nozzle base at or toward its first end formed with the interior wall of the product and a nozzle opening at or toward its second end configured to allow fluid communication between the interior of the product and the product's environment. In embodiments where the nozzle is configured to receive one or more component parts forming the product's nozzle, the nozzle opening is configured to allow fluid communication between the interior of the product and the product's nozzle, thereby allowing the product's nozzle to communicate with the product's environment. In embodiments, the nozzle body may be substantially tubular in form. The nozzle body may include an interior wall defining a channel, the channel configured to allow fluid communication between the interior of the product and the nozzle opening. The channel may have a substantially constant cross-section along a substantial length of the channel. Preferably, the channel may be substantially circular in cross-section. However, in other embodiments, the channel may be of another shape in cross-section, such as square, oval, elliptical, or triangular. Alternatively, the channel may have a varying cross section along a substantial length of the channel.

[0013] The inner wall of the nozzle body may be disposed substantially parallel to the longitudinal axis of the nozzle. Alternatively, the inner wall of the nozzle body may not be disposed substantially parallel to the longitudinal axis of the nozzle. For example, the inner wall of the nozzle body may have an inner sidewall surface that converges inward (i.e., is convex). In embodiments, at least a portion of the inner wall of the nozzle body may be angled relative to the longitudinal axis of the nozzle, such that the channel is wider at the exterior-facing end of the channel. In embodiments, the angled portion of the inner wall is located at the exterior end of the channel. In embodiments, the angled portion of the inner wall coincides with a substantial portion of the inner wall. In another embodiment, the angled portion of the inner wall is a chamfered surface at the exterior end of the channel. In embodiments, the angled portion of the inner wall is angled at an angle of about 1° to about 90° relative to the longitudinal axis of the nozzle. In embodiments, the chamfered surface is angled at an angle of about 1° to about 90° relative to the longitudinal axis of the nozzle. In embodiments, the angled portion of the inner wall defines a sealing surface. In embodiments, the sealing surface is configured to engage a sealing device. In embodiments, the sealing surface is configured to accommodate a substantially radially directed load from the sealing device. In embodiments, the sealing surface is configured to accommodate a substantially axially directed load from the sealing device. In embodiments, the sealing surface is configured to accommodate a load directed at between about 1° and about 89° from the sealing device.

[0014] In embodiments, the or each nozzle includes a base transition portion between the inner wall of the article and the nozzle. Preferably, the base transition portion is substantially curved, thereby defining a smooth transition profile between the inner wall of the article and the nozzle. The radius of curvature of the base transition portion can range from about 1 mm to about 1000 mm, or from about 1 mm to about 500 mm, or from about 5 mm to about 1000 mm, or from about 5 mm to about 500 mm, or from about 1 mm to about 100 mm, or from about 5 mm to about 100 mm. Advantageously, in such embodiments, rotomolded articles can be more easily formed during rotational molding due to the provision of a suitable curved surface profile that allows for improved contact time between the mold used to form the article and the one or more thermoplastic polymers and one or more fibrous materials. As a result, a more consistent bond between the one or more fibrous materials and the one or more thermoplastic polymers is achieved.

[0015] In embodiments, the or each nozzle may include multiple nozzle openings at or towards its second end.

[0016] Preferably, the or each nozzle includes a flared region adjacent the nozzle opening, whereby the diameter of the flared region is greater than the diameter of at least a portion of the nozzle body. For example, the diameter of the flared region may be greater than the diameter of the nozzle body immediately adjacent the flared region. Advantageously, the present invention provides an integrally formed, multi-layered nozzle having a greater width dimension at the nozzle opening. In embodiments, the flared region includes a flanged end. The flanged end may be configured to facilitate connection of one or more components to a product. For example, the flanged end may be configured to facilitate a fluidly sealed connection between the one or more components and the product. In embodiments, the flanged end includes an outer wall adapted to engage the one or more components. In such embodiments, the one or more components may abut the outer wall, thereby forming a fluidly sealed connection with the nozzle. In another embodiment, the flanged end includes an inner wall adapted to engage the one or more components. In such embodiments, the one or more components may be received between the inner wall, thereby forming a fluidly sealed connection with the nozzle. Preferably, the flanged end is substantially concentric with the nozzle body.

[0017] In another embodiment, the or each nozzle includes a flared region between the nozzle opening and the interior of the product, whereby the diameter of the flared region is larger than the diameter of at least a portion of the nozzle body. For example, the diameter of the flared region may be larger toward the interior of the container and / or toward the nozzle opening than the diameter of the nozzle body directly adjacent the flared region. Advantageously, the present invention provides an integrally formed, multi-layered nozzle having a larger width dimension between the interior of the container and the nozzle opening. In an embodiment, the flared region includes a flange. The flange may be configured to facilitate connection of one or more components to the product. For example, the flange may be configured to facilitate a fluidly sealed connection between the one or more components and the product. In one embodiment, the flange includes an outer wall adapted to engage the one or more components. In such an embodiment, the one or more components may abut the outer wall, thereby forming a fluidly sealed connection with the nozzle. In another embodiment, the flange includes an inner wall adapted to engage the one or more components. In such an embodiment, the one or more components may be received between the inner walls, thereby forming a fluidly sealed connection with the nozzle. Preferably, the flange is substantially concentric with the nozzle body.

[0018] Preferably, the or each nozzle includes a nozzle transition portion between the flared region and the nozzle body. For example, the or each nozzle may include a nozzle transition portion between the flanged end and the nozzle body. Preferably, the nozzle transition portion is substantially curved, thereby defining a smooth transition profile between the flared region and the nozzle body. The radius of curvature of the transition portion may be in the range of about 1 mm to about 1000 mm, or about 1 mm to about 500 mm, or about 5 mm to about 1000 mm, or about 5 mm to about 500 mm, or about 1 mm to about 100 mm, or about 5 mm to about 100 mm.

[0019] In embodiments, the exterior surface profile of the or each nozzle is substantially continuous with the inner wall, i.e., there is a seamless transition between the inner wall of the product, the nozzle body, and the flared region. In preferred embodiments, the base transition portion and the nozzle transition portion are all substantially curved.

[0020] In one embodiment, the or each nozzle base is substantially formed tangent to the interior wall of the product. In another embodiment, the product includes one or more recesses oriented toward the interior of the product, and the or each nozzle base is formed within the respective recesses. In such an embodiment, the or each nozzle can be substantially within its respective recess, i.e., the nozzle is substantially entirely contained within its respective recess. Such an arrangement can be advantageous when the external clearance around the product does not allow space for the nozzle or any components associated with the nozzle. In another embodiment, the product includes one or more protrusions oriented away from the interior of the product, and the or each nozzle base is formed on the respective protrusion.

[0021] The article may include a reinforcement material to increase the strength and / or stiffness of the nozzle. In an embodiment, the or each nozzle is reinforced with a fiber-reinforced polymer and one or more thermosetting polymers, the fiber-reinforced polymer and one or more thermosetting polymers are disposed on a second layer around the nozzle, and the one or more fiber materials are at least partially infiltrated with both the one or more thermoplastic polymers and the one or more thermosetting polymers.

[0022] In embodiments, the one or more thermoplastic polymers in the first layer include one or more of an ethylene homopolymer, an ethylene copolymer, a propylene homopolymer, a propylene copolymer, a fluoropolymer, a polyvinyl chloride, a polyvinylidene chloride, a polyaryletherketone (e.g., a polyetheretherketone), and a polyamide.

[0023] In an embodiment, the one or more fibrous materials of the second layer include one or more of ceramic fibers and polymeric fibers.

[0024] In an embodiment, the one or more ceramic fibers in the second layer include one or more of glass fibers, carbon fibers, and basalt fibers, or precursors thereof.

[0025] The one or more polymeric fibers may include one or both of a synthetic polymer and a natural polymer.

[0026] The one or more polymeric fibers may comprise one or more of a polyamide and a polyolefin. Suitable polyolefins include polyethylene and polypropylene.

[0027] In embodiments, the one or more fibrous materials comprise one or more textured woven materials. The one or more textured woven materials may comprise one or more of woven, knit, and braided materials. The one or more textured woven materials comprise plied yarns. In embodiments, the spacing between at least some of the yarns of the fibrous material of the second layer is between about 0.01 micrometers and about 5000 micrometers, or between about 0.1 micrometers and about 5000 micrometers, or between about 1 micrometer and about 5000 micrometers, or between about 10 micrometers and about 5000 micrometers.

[0028] The article may include a third layer including a plurality of filaments selected from one or more of carbon, glass, aramid, and basalt filaments and one or more thermosetting polymers, the second layer being disposed between the first and third layers, and the one or more fibrous materials being at least partially infiltrated with both the one or more thermoplastic polymers and the one or more thermosetting polymers. The third layer may be the same as or separate from the reinforcing material for increasing the strength and / or stiffness of the nozzle.

[0029] In embodiments, the one or more thermosetting polymers of the third layer include one or more of vinyl esters, bismaleimides, polyesters, polyacrylates, epoxies, and polyurethanes.

[0030] In embodiments, the plurality of filaments of the third layer have a filament diameter of from about 0.1 micrometers to about 500 micrometers, or from about 0.1 micrometers to about 100 micrometers, or from about 0.1 micrometers to about 50 micrometers, or from about 1 micrometer to about 20 micrometers.

[0031] In embodiments, the plurality of filaments of the third layer are in the form of one or more of wound filaments, a fabric section comprising a plurality of threads, braided yarns, and chopped fibers.

[0032] In an embodiment, the first layer has a thickness of about 0.1 mm to about 50 mm, the second layer has a thickness of about 0.1 mm to about 5 mm, and the third layer has a thickness of about 0.1 mm to about 1000 mm.

[0033] In an embodiment, the thermoplastic polymer is embedded in the interstices between the threads of the fibrous material of the second layer.

[0034] In an embodiment, the thermoplastic polymer is embedded within the structure of the individual threads of the fibrous material of the second layer.

[0035] In an embodiment, tendrils of fibrous material of the second layer extend from the surface of the yarn into the first layer.

[0036] In embodiments, the thermoplastic polymer does not completely infiltrate the thickness of the fibrous layer, i.e., at least a portion of the surface of the fibrous layer is not completely penetrated by the thermoplastic polymer. Preferably, substantially all of the surface of the fibrous layer is not completely penetrated by the thermoplastic polymer.

[0037] In embodiments, the product includes a recess disposed around the periphery of the or each nozzle. The recess may extend through the outer wall of the thermoplastic polymer / fiber material composite. The recess is configured to facilitate engagement of one or more subsequent layers with the first and second layers. For example, the recess may be configured to facilitate engagement between a hollow thermoplastic polymer / fiber material composite and one or more subsequent layers. The recess and the nozzle may be coaxial. Preferably, the recess includes a base adapted to facilitate engagement of the thermoplastic polymer / fiber material composite with one or more subsequent layers. The base may include an engagement surface against which at least a portion of the one or more subsequent layers may abut. The engagement surface may be substantially planar. The recess may have a depth between about 1 mm and about 200 mm, or between about 1 mm and about 100 mm, or between about 5 mm and about 50 mm. The recess may further include a sidewall. Preferably, the sidewall tapers inward from the outer wall of the thermoplastic polymer / fiber material composite to the base of the recess. Advantageously, the inwardly tapered sidewalls facilitate improved introduction and engagement of one or more subsequent layers with the thermoplastic polymer / fiber material composite.

[0038] In embodiments, one or more component parts forming a nozzle of a product include a first adapter configured to connect to a respective one of the nozzles. In embodiments, the first adapter includes a flanged end. The first adapter may be configured to connect to an outer wall of the nozzle. In embodiments, the first adapter is formed of a carbon fiber reinforced polymer. In embodiments, adhesive or other attachment means may be provided between the first adapter and the outer wall of the nozzle to facilitate connection therebetween. In embodiments, the first adapter is configured to connect to the reinforcement material (e.g., a fiber reinforced polymer). Preferably, the adhesive or other attachment means is provided between the first adapter and the reinforcement material. Preferably, the first adapter is configured to facilitate connection of an external component to the product. For example, the first adapter may facilitate connection to one or more of a pipe, a valve, a sensor, a closure, and a probe.

[0039] In embodiments, one or more component parts forming a nozzle for a product include a second adapter configured to connect to a respective one of the nozzles. In embodiments, the second adapter includes a flanged end. The second adapter may be configured to connect to an outer wall of the nozzle. In embodiments, the second adapter is formed of a thermoplastic polymer. For example, the thermoplastic polymer may be polyethylene. In embodiments, the second adapter is configured to be at least partially received in a channel of the nozzle body. Preferably, the second adapter is sealingly engaged with an angled portion of the inner wall of the nozzle body, and a sealing device may be received between the second adapter and the angled portion of the inner wall of the nozzle body. In embodiments, the second adapter is configured to operably engage with the first adapter. Preferably, the flanged end of the first adapter includes an upper engagement surface, and the flanged end of the second adapter includes a lower engagement surface, and the lower engagement surface of the second adapter is configured to operably engage with the upper engagement surface of the first adapter. Preferably, the second adapter is of substantially the same shape as the first adapter.

[0040] In embodiments, at least one of the nozzles (or at least one of the nozzles of a product formed from the one or more component parts) is configured to be attached to a closure, where the closure prevents fluid communication between an interior of the product and an environment external to the product. In embodiments, the first adapter is configured to operably engage with the closure. In embodiments, the second adapter is configured to operably engage with the closure. In embodiments, the first and second adapters are configured to operably engage with the closure together. In embodiments, the flanged end of the second adapter includes an upper engagement surface against which at least a portion of the closure abuts when the closure is attached thereto.

[0041] In embodiments, the product further includes a closure for preventing fluid communication between the interior of the product and an environment external to the product. In embodiments, the closure is formed from a combination of a fiber-reinforced polymer and a suitable metal. For example, the metal may be stainless steel. In embodiments, the fiber-reinforced polymer includes a carbon fiber-reinforced polymer. In embodiments, the closure includes a thermoplastic polymer lining. For example, the thermoplastic polymer lining may be polyethylene.

[0042] In embodiments, the sealing device includes one or more sealing components, at least one of which may be in the form of a ring-shaped gasket.

[0043] In a preferred form, the product is a hollow composite container, which may be generally spherical, cylindrical, spherocylindrical, rectangular, or of any other shape commonly known in the art.

[0044] In a second aspect, the present disclosure provides a method of producing a hollow composite container, the method comprising: applying one or more fibrous materials to an interior surface of a hollow mold, the hollow mold including structures that protrude away from the interior of the mold; heating and rotating a hollow mold in the presence of one or more thermoplastic polymers within the hollow mold such that the polymers melt and at least partially infiltrate the fibrous material; cooling the mold so that the thermoplastic polymer solidifies; and removing the hollow thermoplastic polymer / fiber material composite container from the mold, the hollow thermoplastic polymer / fiber material composite container having structures projecting away from the interior of the container.

[0045] Advantageously, the present invention allows for the production of a hollow composite container having a substantially thermoplastic inner / first layer with a substantially fibrous second layer. The fibrous second layer can function as a suitable tie layer adapted to allow additional layers to be formed therewith. The thermoplastic inner layer can function as a barrier layer that is substantially impermeable to materials that contact the interior of the container. Furthermore, the integrally formed structure of the container is seamlessly integrated into this same multi-layered container. Therefore, there are no welds or bond lines between the container and the integrally formed structure.

[0046] It should be understood that references to a thermoplastic polymer / fibrous material composite container are references to a hollow composite container when it has only the fibrous material and thermoplastic polymer layers in question.

[0047] In embodiments, the method comprises one or more of the following: applying a plurality of filaments selected from one or more of carbon, glass, aramid, and basalt filaments to the exterior of the hollow thermoplastic polymer / fiber material composite container, wherein prior to application, the plurality of filaments are at least partially wetted with one or more thermosetting polymers; applying a plurality of filaments selected from one or more of carbon, glass, aramid, and basalt filaments to the exterior of a hollow thermoplastic polymer / fiber material composite container, followed by applying one or more thermosetting polymers; The method further includes applying one or more thermosetting polymers to the exterior of the hollow thermoplastic polymer / fiber material composite container, followed by applying a plurality of filaments selected from one or more of carbon, glass, aramid, and basalt filaments.

[0048] Advantageously, providing this additional layer on the outside of the hollow thermoplastic polymer / fiber material composite container results in increased strength of the produced hollow composite container. The fibrous layer of the hollow thermoplastic polymer / fiber material composite container facilitates bonding of this additional layer thereto. Preferably, application of this additional layer results in the one or more fibrous materials being at least partially infiltrated with both one or more thermoplastic polymers and one or more thermosetting polymers.

[0049] In an embodiment, the step of applying one or more fibrous materials to the inner surface of the hollow mold includes fixing the one or more fibrous materials to the inner surface of the hollow mold. The hollow mold may include fixing means (e.g., a fixing device) for fixing the one or more fibrous materials to the inner surface of the hollow mold. In an embodiment, the method further includes holding the one or more fibrous materials to the inner surface of the hollow mold while heating and rotating the hollow mold. For example, gas pressure may be used to hold the one or more fibrous materials to the inner surface of the hollow mold. This may be achieved by supplying a gas flow to the interior of the rotational molding device (in which the hollow mold is heated and rotated), thereby applying a pressure differential across the one or more fibrous materials to press the one or more fibrous materials against the inner surface of the hollow mold. In an embodiment, a combination of gas pressure and a fixing device may be employed to fix the one or more fibrous materials to the inner surface of the hollow mold.

[0050] Applying one or more fibrous materials to the interior surface of the hollow mold may include applying one or more of ceramic fibers and polymer fibers. The applying one or more ceramic fibers may include one or more of glass fibers, carbon fibers, and basalt fibers, or precursors thereof. The applying one or more polymer fibers may include one or both of synthetic polymers and natural polymers. The one or more polymer fibers may include one or more of polyamides and polyolefins. Suitable polyolefins include polyethylene and polypropylene.

[0051] The one or more thermoplastic polymers may include one or more of an ethylene homopolymer, an ethylene copolymer, a propylene homopolymer, a propylene copolymer, a fluoropolymer, a polyvinyl chloride, a polyvinylidene chloride, a polyaryletherketone (e.g., a polyetheretherketone), and a polyamide. Preferably, the one or more thermoplastic polymers are provided in powder form.

[0052] In embodiments, the one or more fibrous materials comprise one or more textured woven materials. The one or more textured woven materials may comprise one or more of woven, knit, and braided materials. The one or more textured woven materials comprise plied yarns. In embodiments, the spacing between at least some of the yarns of the fibrous material is between about 0.01 micrometers and about 5000 micrometers, or between about 0.1 micrometers and about 5000 micrometers, or between about 1 micrometer and about 5000 micrometers, or between about 10 micrometers and about 5000 micrometers.

[0053] The one or more thermosetting polymers may include one or more of vinyl esters, bismaleimides, polyesters, polyacrylates, epoxies, and polyurethanes.

[0054] In embodiments, the plurality of filaments have a filament diameter of from about 0.1 micrometers to about 500 micrometers, or from about 0.1 micrometers to about 100 micrometers, or from about 0.1 micrometers to about 50 micrometers, or from about 1 micrometer to about 20 micrometers.

[0055] In embodiments, the plurality of filaments is in the form of one or more of wound filaments, a fabric section comprising multiple threads, braided yarn, and chopped fibers.

[0056] In an embodiment, the first layer has a thickness of about 0.1 mm to about 50 mm, the second layer has a thickness of about 0.1 mm to about 5 mm, and the additional layer has a thickness of about 0.1 mm to about 1000 mm.

[0057] In an embodiment, the thermoplastic polymer is embedded in the interstices between the threads of the fibrous material of the second layer.

[0058] In an embodiment, the thermoplastic polymer is embedded within the structure of the individual threads of the fibrous material of the second layer.

[0059] In an embodiment, tendrils of fibrous material of the second layer extend from the surface of the yarn into the first layer.

[0060] In embodiments, the thermoplastic polymer does not completely infiltrate the thickness of the fibrous layer, i.e., at least a portion of the surface of the fibrous layer is not completely penetrated by the thermoplastic polymer. Preferably, substantially all of the surface of the fibrous layer is not completely penetrated by the thermoplastic polymer.

[0061] Preferably, the structure of the container is configured to allow fluid communication between the interior of the container and the environment outside the container. The method may include drilling or otherwise creating one or more holes through and into the structure of the container. The one or more holes may allow fluid communication between the interior of the container and the environment outside the container. Alternatively, the formed structure of the container may already be configured to allow fluid communication between the interior of the container and the environment outside the container when removed from the mold.

[0062] The structure of the container may be one or more nozzles. The or each nozzle may be of the form described in the previous aspect of the invention. As previously mentioned, the or each nozzle may respectively form one or more nozzles of the container, or in alternative embodiments, the or each nozzle is configured to receive one or more component parts forming one or more respective nozzles of the container.

[0063] In an embodiment, the method may include forming or molding a structure of the container into one or more nozzles.

[0064] In embodiments, the hollow mold features projecting away from the interior of the mold are one or more nozzle mold segments adapted to produce one or more nozzles of the same configuration within the hollow composite container. The one or more nozzle mold segments may be integrally formed with the hollow mold. Alternatively, the method includes fixedly connecting one or more nozzle mold segments to the hollow mold, thereby forming a hollow mold feature projecting away from the interior of the mold. Preferably, the one or more nozzle mold segments each include an internal flared region configured to form a corresponding flared region in the formed nozzle. Preferably, the one or more nozzle mold segments are adapted to include a parting line in a plane subtended by the axial and radial directions of the nozzle mold segments.

[0065] The flared region of the nozzle may be formed adjacent to the nozzle opening of the formed nozzle. Alternatively, the flared region of the nozzle may be formed between the nozzle opening and the interior of the container.

[0066] In an embodiment, the method further includes forming or molding a flared region into the flanged end of the nozzle.

[0067] In an embodiment, the method may further include reinforcing the or each nozzle with a fiber-reinforced polymer and one or more thermosetting polymers, the fiber-reinforced polymer and the one or more thermosetting polymers being disposed on one or more fibrous materials around the nozzle, the one or more fibrous materials being at least partially infiltrated with both the one or more thermoplastic polymers and the one or more thermosetting polymers.

[0068] In an embodiment, the method further includes forming a recess in the outer wall of the hollow thermoplastic polymer / fiber material composite container around a periphery of the nozzle. The hollow mold may include protrusions disposed around the periphery of the structure that protrude toward the interior of the mold, thereby forming the recess extending through the outer wall of the hollow thermoplastic polymer / fiber material composite container. Alternatively, the recess may be formed after the hollow thermoplastic polymer / fiber material composite container is removed from the mold.

[0069] In embodiments, drilling or otherwise creating one or more holes through the container includes creating holes through the container after applying a filament layer, the holes configured to receive one or more component parts forming a nozzle of the container. In embodiments, the method further includes assembling the one or more component parts from the nozzle of the container. In embodiments, the assembling includes connecting a first adapter to each one of the nozzles. In embodiments, the assembling includes providing adhesive or other attachment means between the first adapter and the nozzle to facilitate the connection. In embodiments, the assembling includes connecting a second adapter to each one of the nozzles. Preferably, the connecting includes at least partially receiving the second adapter within a channel of the nozzle body. In embodiments, the assembling includes providing a sealing device between the nozzle body and the second adapter before connecting the second adapter to the nozzle. In embodiments, the assembling includes operably engaging the first adapter and the second adapter. The first and second adapters may be of the form described in the previous aspect of the invention.

[0070] In embodiments, the method further includes providing a closure for preventing fluid communication between the interior of the container and an environment external to the container. In embodiments, providing the closure includes operably engaging the closure with a first adapter. In embodiments, providing the closure includes operably engaging the closure with a second adapter. In embodiments, providing the closure includes operably engaging the closure with the first and second adapters. In embodiments, providing the closure includes operably engaging the closure with the flanged end of the second adapter, e.g., an upper engagement surface thereof.

[0071] It will be appreciated that the second aspect of the invention may include any of the features defined in relation to the first aspect of the invention.

[0072] In a third aspect, the present invention provides a hollow composite container having an interior wall defining an interior of the container and integrally formed with the interior wall, an integrally formed structure projecting away from the interior of the container, the container being formed from a first layer comprising one or more thermoplastic polymers and a second layer comprising one or more fibrous materials.

[0073] It will be appreciated that the third aspect of the invention may include any of the features defined in relation to the first and second aspects of the invention.

[0074] As used herein, unless the context otherwise requires, the term "comprise" and variations of the term such as "comprising," "comprises," and "comprised" are not intended to exclude further appendants, components, integers, or steps.

[0075] Further aspects of the invention, and further embodiments of the aspects described in the previous paragraphs, will become apparent from the following description, given by way of example and with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0076] [Figure 1] 1 shows a perspective view of a hollow composite container according to an embodiment of the present invention. [Figure 2] 2 shows a cross-sectional view of the hollow composite container of FIG. 1. [Figure 3] 1 shows a cross-sectional view of a portion of a nozzle of a container, including showing its multi-layer structure. [Figure 4] 1 shows a cross-sectional view of a nozzle according to an embodiment of the present invention. [Figure 5] 10 shows a cross-sectional view of another nozzle according to an embodiment of the present invention. [Figure 6]10 shows a cross-sectional view of another nozzle according to an embodiment of the present invention. [Figure 7] 1 shows a perspective view of another hollow composite container according to an embodiment of the present invention. [Figure 8] 8 shows a front cross-sectional view of the hollow composite container of FIG. 7. [Figure 9] 1 shows a perspective view of another hollow composite container according to an embodiment of the present invention. [Figure 10] 10 shows a cross-sectional view of the hollow composite container of FIG. [Figure 11] 1 shows a cross-sectional view of a portion of a nozzle of a container, including showing the multi-layer structure of the container. [Figure 12] 1 shows a cross-sectional view of a portion of a nozzle of a container, including showing its multi-layer structure. [Figure 13] 1 shows a cross-sectional view of a portion of a nozzle of a container, including showing its multi-layer structure. [Figure 14] 1 shows a cross-sectional view of a portion of a nozzle of a container, including showing its multi-layer structure. [Figure 15] 1 shows a cross-sectional view of a portion of a nozzle of a container, including showing its multi-layer structure. [Figure 16] 1 shows a cross-sectional view of a portion of a nozzle of a container, including showing its multi-layer structure. [Figure 17] 10 shows a perspective cross-sectional view of a portion of a nozzle formed from component parts of another embodiment of a vessel; [Figure 18] 10 shows a perspective cross-sectional view of a portion of a nozzle formed from component parts of another embodiment of a vessel; [Figure 19] 10 shows a perspective cross-sectional view of a portion of a nozzle formed from component parts of another embodiment of a vessel; [Figure 20] 18 shows a front cross-sectional view of FIG. 17. [Figure 21] 10 shows a cross-sectional front view of a nozzle formed from component parts of another embodiment of a vessel; [Figure 22] 10 shows a perspective partial cutaway view of a nozzle formed from component parts of a container according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0077] 1-3, which depict a rotomolded product in the form of a hollow composite container 10. As will be appreciated from the following description, container 10 is suitable for use in containing and transporting hazardous materials, including chemicals and the like. However, it will be readily appreciated that container 10 may be used to contain and transport non-hazardous items as well as in similar sectors such as the construction of fuel and cargo tanks for transportation vehicles, in aerospace applications, and for the storage and transport of pressurized gases and cryogenic materials.

[0078] As explained in more detail below, container 10 is formed in part by a rotational molding process, which, in the case of container 10, results in the formation of a multi-layered structured container. As used herein, reference to a hollow thermoplastic polymer / fiber material composite container (or the like) is a reference to a container produced as a direct result of the rotational molding process, while reference to a hollow composite container (or the like) may also include reference to modified forms of the hollow thermoplastic polymer / fiber material composite container. For example, in certain applications, additional layers are added to the hollow thermoplastic polymer / fiber material composite container after the rotational molding process to create a container suitable for such applications. Thus, for the avoidance of doubt, hollow composite container 10 includes additional layers added to the hollow thermoplastic polymer / fiber material composite container after the rotational molding process. Multi-layer structures will be explained in more detail below.

[0079] In the depicted embodiment, the container 10 is of a substantially spherocylindrical shape, however, alternative container shapes such as cylindrical, rectangular, or any other shape commonly known in the art may also be provided.

[0080] Referring to FIG. 2 , a container 10 includes an interior wall 12 that defines an interior 14 of the container 10. The container 10 further includes structure integrally formed with the interior wall 12 in the form of a plurality of nozzles 30 that protrude away from the interior 14 of the container 10. It will be understood from at least FIG. 3 that the nozzles 30 of the container 10 are seamlessly integrated into the container 10 with the same multi-layer structure as the rest of the container 10. Thus, there is no weld line between the container 10 and the nozzles 30. This is in stark contrast to known prior art container production, particularly for polymer-based containers, which typically requires pre-fabricated nozzles to be separately attached to the container. This often involves creating holes in the container and then attaching the nozzles to the holes (e.g., via welding or other fastening methods). However, the present inventors have successfully manufactured containers with integrally formed nozzles, all formed with the same multi-layer structure. This eliminates the need for post-container attachment of the nozzles, thereby resulting in the nozzles being seamlessly integrated into the overall structure of the container.

[0081] Referring to FIG. 4 , the nozzle 30 includes a substantially tubular nozzle body 32. The nozzle body 32 includes, at a first inner end 31, a nozzle base 34 formed by the interior wall 12 of the container 10, and, at a second outer end 33 of the nozzle body, a nozzle opening 35 configured to allow fluid communication between the interior 14 of the container 10 and an environment external to the container 10. The nozzle body 32 further includes an inner wall 36 defining a channel 37. As shown in FIG. 4 , the inner wall 36 of the nozzle body 32, when viewed in longitudinal cross section, is disposed substantially parallel to the longitudinal axis of the nozzle. The channel 37 is configured to allow fluid communication between the interior 14 of the container 10 and the nozzle opening 35.

[0082] From the longitudinal cross-sectional view of the nozzle 30 in FIG. 4, it can be seen that the nozzle 30 is seamlessly integrated with the interior wall 12 of the container 10. As shown in the figure, the nozzle base 34 defines a substantially curved base transition portion 38 between the interior wall 12 of the container 10 and the nozzle 30, thereby defining a smooth transition profile between the interior wall 12 and the nozzle 30. The radius of curvature of the base transition portion 38 can range from about 1 mm to about 1000 mm. Providing the base transition portion 38 enhances the manufacturability of the container 10 with the integrally formed nozzle 30. One of the challenges in manufacturing the container 10 is the hollow thermoplastic polymer / fiber material composite, which is ensuring sufficient contact time between the thermoplastic polymer and the fiber material throughout the hollow mold during the rotational molding process. Because rotational molding of complex shaped multilayer structures presents many challenges, providing a hollow mold with a shaped portion corresponding to the substantially curved base transition portion 38 enhances contact time between the thermoplastic polymer and the fiber material around this complex portion of the mold.

[0083] It will be appreciated that the channel 37 is widest at the inner end 31 because, from the perspective of the base transition portion 38, the distance between the opposing surfaces of the inner wall 36 is widest. The inner wall 36 initially tapers smoothly inward toward the outer end 33 until the distance between the opposing surfaces of the inner wall 36 becomes constant. As a result, the portion of the channel 37 toward the outer end 33 has a substantially constant cross-section. It will be appreciated that the channel 37 is substantially circular in cross-section. However, in other embodiments, the channel may be of another shape in cross-section, such as square, oval, elliptical, and triangular.

[0084] The nozzle 30 includes a flared region, which in this embodiment is in the form of a flange 42 adjacent the nozzle opening 35 and is integrally formed as part of the nozzle 30. The flange 42 is therefore also formed of the same multi-layer structure as the nozzle 30 and the rest of the container 10 (as shown in FIG. 3). The flange 42 is disposed substantially concentrically with the nozzle body 32. The flange 42 generally has a diameter ΦD1 that is larger than the diameter of the nozzle body 32, specifically, a diameter ΦD2 of the nozzle body 32 directly adjacent the flange 42. The flange 42 is configured to facilitate connection between the nozzle 30 and one or more external components. Examples of components that may be connected to the nozzle 30 via the flange 42 include pipes, valves, sensors, and probes.

[0085] In this embodiment, the flange 42 includes an outer wall 45 and an inner wall 46. The outer wall 45 and / or the inner wall 46 can be adapted to engage with the one or more components. For example, the one or more components can be clamped onto, connected to, or otherwise abut the outer wall 45, and / or can be clamped onto, connected to, or otherwise abut the inner wall 46. In some applications, a fluidly sealed connection with the nozzle 30 is desired, in which case a suitable sealing component can be provided between the flange 42 and one or more external components. Alternatively, the flange 42 itself can be configured to facilitate a fluidly sealed connection between the nozzle 30 and one or more external components.

[0086] Referring now to FIG. 5, this provides an alternative embodiment of nozzle 30'. Nozzle 30' is similar to nozzle 30 in many respects, and these similarities will not be discussed again here. The primary difference between nozzle 30' and nozzle 30 is that nozzle 30' includes a flared end 42' adjacent nozzle opening 35' and is integrally formed as part of nozzle 30'. Flared end 42' generally has a diameter ΦD1 that is larger than the diameter of nozzle body 32', specifically, a diameter D1 that is larger than a diameter ΦD2 of nozzle body 32' directly adjacent flared end 42'.

[0087] Referring now to FIG. 6, this provides another alternative embodiment of nozzle 30″. Nozzle 30″ is similar to nozzle 30 in many respects, and these similarities will not be discussed again here. The primary difference between nozzle 30″ and nozzle 30 is that nozzle 30″ includes a relatively deep flange 42″ adjacent nozzle opening 35″ and integrally formed as part of nozzle 30′. Flange 42″ generally has a diameter ΦD1 that is larger than the diameter of nozzle body 32″, and specifically, has a diameter D1 that is larger than diameter ΦD2 of nozzle body 32″ directly adjacent flared end 42′.

[0088] Although not shown in the accompanying figures, the nozzles 30, 30', 30" generally are provided with a substantially curved nozzle transition portion between the nozzle body 32, 32', 32" and the flange / flare end 42, 42', 42" to define a smooth transition profile between the nozzle body 32, 32', 32" and the flange / flare end 42, 42', 42". The radius of curvature of the nozzle transition portion may be in the range of about 1 mm to about 1000 mm. Thus, the exterior surface profile of the nozzle 30, 30', 30" is substantially continuous with the inner wall 12, i.e., there is a seamless transition between the inner wall 12, the nozzle body 32, 32', 32" and the flange / flare end 42, 42', 42".

[0089] As can be seen from the above embodiment, each nozzle 30, 30', 30" is integrally formed with the container 10 having the same multi-layer structure, whereby each nozzle has a larger width dimension at the nozzle opening relative to the nozzle body. Thus, the challenges associated with forming a multi-layered container with such a nozzle structure in a rotational molding process have been overcome by the inventors through a preferred design of the nozzle mold, which includes having a parting line in a plane bounded by the axial and radial directions of the nozzle mold parts.

[0090] 1-3, it will be appreciated that the nozzle base 32 of each nozzle 30 is formed substantially tangent to the interior wall 12 of the container 10. However, this does not have to be the case.

[0091] 7 and 8, a container 100 is provided having a plurality of recesses 150 oriented toward the interior 114 of the container 100. In this embodiment, each nozzle base 132 is formed at the base of each respective recess 150 such that each nozzle 130 is fully contained within its respective recess 150. Such an arrangement is advantageous when external clearance around the container is limited and therefore does not allow space for the nozzles 130 and / or any components attached to the nozzles 130.

[0092] 9 and 10, a container 200 is provided having a plurality of protrusions 250 oriented away from the interior 214 of the container 200. In this embodiment, each nozzle base 232 is formed on each respective protrusion 250 such that each nozzle 230 extends from its respective protrusion 250. Such an arrangement can be advantageous in certain applications. For example, one suitable application is to attach a closure to a sump located at the lowest point of the container for drainage purposes.

[0093] While the depicted embodiment shows a container having multiple nozzles, it will be understood that in other embodiments, the container may include a single nozzle. Further, as demonstrated by the depicted embodiment, the nozzles may be located anywhere on the container (e.g., nozzles may be located on any one or more of the body of the container, at the end of the container, on the top surface of the container, on the bottom surface of the container, and on the side surface of the container).

[0094] The container 10 is formed of a multi-layer structure (best shown in FIG. 3 ) including a first inner layer 22 comprising one or more thermoplastic polymers and a second layer 24 comprising one or more fibrous materials. As a result of a rotational molding process, described in more detail below, the one or more fibrous materials are at least partially infiltrated with one or more thermoplastic polymers. The thermoplastic polymer inner layer 22 functions as a barrier layer that is substantially impermeable to materials that contact the inner layer 22, while the fibrous outer layer 24 functions as a suitable tie layer adapted to allow additional layers to be formed therewith. Furthermore, the nozzle 30 of the container 10 is seamlessly integrated into the container 10, which has the same multi-layer structure with the first and second layers. Therefore, there is no weld seam between the container 10 and the nozzle 30.

[0095] Preferably, thermoplastic polymers for use in the construction of first layer 22 are resistant to a variety of substances and conditions, such as one or more of high pH, ​​low pH, oxidizing agents, reducing agents, solvents, propellants, cryogenic substances, permeation, and abrasion.

[0096] The one or more thermoplastic polymers of the first layer 22 may include one or more of an ethylene homopolymer, an ethylene copolymer, a propylene homopolymer, a propylene copolymer, a fluoropolymer, a polyvinyl chloride, a polyvinylidene chloride, a polyaryletherketone (e.g., a polyetheretherketone), and a polyamide.

[0097] Suitable fluoropolymers include one or more of polyvinyl fluoride, polyvinylidene fluoride, polytetrafluoroethylene, perfluoroalkoxyalkanes, fluorinated ethylene-propylene, ethylene tetrafluoroethylene, ethylene chlorotrifluoroethylene, polyethylene tetrafluoroethylene, and polyethylene chlorotrifluoroethylene.

[0098] The one or more fibrous materials of the second layer 24 may include one or more of ceramic fibers and polymeric fibers.

[0099] The hollow thermoplastic polymer / fiber material composite container 10 can be used in some applications without further modification. However, for other applications, it is preferable that the container 10 be reinforced. Such reinforcement can be applied only to increase the strength and rigidity of the nozzle 30, or to also increase the strength and rigidity of the entire container 10.

[0100] Referring to FIG. 11 , this depicts reinforcement applied to increase the strength and rigidity of the nozzle 30, including the flange 42. In this embodiment, the nozzle 30 is formed substantially tangent to the inner wall 12 or on a protrusion 250. The nozzle 30 is reinforced by providing a fiber-reinforced polymer nozzle reinforcement layer 26. This nozzle reinforcement layer 26 is applied over the second layer 24 along the entire vessel 10 (to increase the strength and rigidity of the entire vessel 10) and along the entire nozzle 30, including the flange 42. As a result of applying the nozzle reinforcement layer 26, the one or more fiber materials of the second layer 24 are at least partially infiltrated with both the one or more thermoplastic polymers of the inner layer 22 and the one or more thermosetting polymers of the nozzle reinforcement layer 26.

[0101] Referring to FIG. 12 , this depicts reinforcement applied to increase the strength and rigidity of the nozzle 30, including the flange 42. In this embodiment, the nozzle 30 is formed substantially tangent to the interior wall 12 or on the protrusion 250. In much the same manner as described with respect to FIG. 11 , the nozzle 30 is reinforced by providing a nozzle reinforcement layer 26 of fiber-reinforced polymer. This nozzle reinforcement layer 26 is applied over the second layer 24 along the entire vessel 10 (to increase the strength and rigidity of the entire vessel 10) and along the entire nozzle 30, including the flange 42. As a result of applying the nozzle reinforcement layer 26, the one or more fiber materials of the second layer 24 are at least partially infiltrated with both the one or more thermoplastic polymers of the interior layer 22 and the one or more thermosetting polymers of the nozzle reinforcement layer 26. In this embodiment, an additional reinforcement layer 28 is provided along the periphery of the vessel 10 immediately adjacent the nozzle 30 and along the entire nozzle 30, including the flange 42.

[0102] Referring to FIG. 13 , this depicts reinforcement applied to increase the strength and rigidity of the nozzle 30, including the flange 42. In this embodiment, the nozzle 30 is formed substantially tangent to the interior wall 12 or on a protrusion 250. The nozzle 30 is reinforced by providing a nozzle reinforcement layer 26 of fiber-reinforced polymer. This nozzle reinforcement layer 26 is applied over the second layer 24 along the periphery of the container 10 immediately adjacent the nozzle 30 and along the entire nozzle 30, including the flange 42. As shown in FIG. 13 , the container 10 includes an insert 46 provided around the periphery of the nozzle 30. The insert 46 includes a base 48 adapted to facilitate engagement of the container 10 to the nozzle reinforcement layer 26 (and any subsequent layers applied to the nozzle 30 and / or the remainder of the container 10). The base 48 includes a substantially planar engagement surface 49 against which the nozzle reinforcement layer 26 may abut. As a result of applying the nozzle reinforcement layer 26, the one or more fibrous materials of the second layer 24 are at least partially infiltrated with both the one or more thermoplastic polymers of the inner layer 22 and the one or more thermosetting polymers of the nozzle reinforcement layer 26. An outermost reinforcement layer 28 of fiber-reinforced polymer can then be applied to the remainder of the container 10 to increase the strength and rigidity of the entire container 10.

[0103] Reference is now made to FIG. 14, which depicts reinforcement applied to increase the strength and rigidity of nozzle 30, including flange 42. In this embodiment, nozzle 30 is formed at the base of recess 150 (similar to the embodiment of FIGS. 7 and 8). In much the same manner as described with respect to FIG. 13, nozzle 30 is reinforced by providing a nozzle reinforcement layer 26 of fiber-reinforced polymer. This nozzle reinforcement layer 26 is applied over second layer 24 along the periphery of container 10 immediately adjacent nozzle 30 (within insert 46), along the peripheral walls of recess 150, and along the entire nozzle 30, including flange 42. An outermost reinforcement layer 28 of fiber-reinforced polymer can then be applied to the remainder of container 10 to increase the strength and rigidity of the entire container 10.

[0104] Reference is now made to FIG. 15, which depicts reinforcement applied to increase the strength and rigidity of the nozzle 30, including the flange 42. In this embodiment, the nozzle 30 is formed substantially tangent to the interior wall 12 or on a protrusion 250. In much the same manner as described with respect to FIG. 11, the nozzle 30 is reinforced by providing a fiber-reinforced polymer nozzle reinforcement layer 26. This nozzle reinforcement layer 26 is applied to the second layer 24 along the periphery of the vessel 10 immediately adjacent the nozzle 30 (in the insert 46) and along the entire nozzle 30, including the flange 42. In this embodiment, an additional reinforcement layer is provided: a fiber-reinforced polymer reinforcement layer 52 may be applied to the entire vessel 10 except for the nozzle 30, and a reinforcement layer 54 is applied along the entire periphery of the vessel 10, including along the entire nozzle 30, including the flange 42.

[0105] Reference is now made to FIG. 16, which depicts reinforcement applied to increase the strength and rigidity of nozzle 30, including flange 42. In this embodiment, nozzle 30 is formed at the base of recess 150 (similar to the embodiment of FIGS. 7 and 8). In much the same manner as described with respect to FIG. 15, nozzle 30 is reinforced by providing a fiber-reinforced polymer nozzle reinforcement layer 26. This nozzle reinforcement layer 26 is applied to second layer 24 along the periphery of container 10 immediately adjacent nozzle 30 (in insert 46) and along the entire nozzle 30, including flange 42. In this embodiment, an additional reinforcement layer is provided: fiber-reinforced polymer reinforcement layer 56 may be applied to the entire container 10 except for nozzle 30, and reinforcement layer 58 is applied along the entire periphery of container 10, including along the entire nozzle 30, including flange 42.

[0106] The reinforcing layer can be applied to the thermoplastic polymer / fiber material composite container in several ways. In one example, the reinforcing layer can be manually hand-laid onto the container 10. In another example, the reinforcing layer can be vacuum-infused. In further examples, the reinforcing layer can include (1) filament winding one or more carbon, glass, aramid, and basalt filaments onto the outside of the container 10 around the nozzle 30, where the filaments are at least partially wetted with one or more thermosetting polymers before application; (2) filament winding one or more carbon, glass, aramid, and basalt filaments onto the outside of the container 10 around the nozzle 30, followed by application of one or more thermosetting polymers; or (3) applying one or more thermosetting polymers onto the outside of the container 10 around the nozzle 30, followed by filament winding one or more carbon, glass, aramid, and basalt filaments. As a result of applying the reinforcing layer, the one or more fibrous materials of the second layer 24 are at least partially infiltrated with both the one or more thermoplastic polymers of the first layer 22 and the one or more thermosetting polymers of the reinforcing layer.

[0107] The one or more thermosetting polymers may include one or more of vinyl esters, bismaleimides, polyesters, polyacrylates, epoxies, and polyurethanes.

[0108] Referring now to FIG. 17 , this depicts the nozzle 350 of the container 300 formed from component parts. In this embodiment, the insert 330 should be understood as a “nozzle” or protruding structure formed during the rotational molding process. While not explicitly depicted in FIG. 17 , the insert 330 is formed from the first layer 322 and the second layer 324 in a manner similar to the previous embodiment. Also, similar to the previous embodiment, an insert 346 adapted to facilitate engagement of the container 300 with the nozzle reinforcement layer 326 is provided, as well as a reinforcement layer 356 applied to the entire container 300 except for the nozzle 350. As shown in FIG. 17 , a structural or non-structural filler material 338 or other bracing structure can be provided between the subsequent nozzle reinforcement 326 and the subsequent reinforcement 356.

[0109] The component parts of the nozzle 350 include a first adapter 360 configured to connect to the exterior surface of the insert 330. The first adapter 360 is formed from a carbon fiber reinforced polymer, although it will be understood that the first adapter 360 may be formed from other suitable materials. The first adapter 360 includes a substantially tubular adapter body 362 and a flanged end 364. The flanged end 364 is disposed toward the exterior of the vessel 300 when the first adapter 360 is connected to the insert 330. An adhesive or other attachment means may be provided to facilitate a suitable connection between the first adapter 360 and the insert 330.

[0110] The component parts of the nozzle 350 further include a second adapter 370 configured to connect to the exterior surface of the insert 330. The second adapter 370 is formed of a thermoplastic polymer such as polyethylene, although it will be understood that the second adapter 370 may be formed of other suitable materials. The second adapter 370 includes a substantially tubular adapter body 372 and a flanged end 374. The flanged end 374 is disposed toward the exterior of the container 300 when the second adapter 370 is connected to the insert 330. While FIG. 17 shows the first and second adapters to be substantially identical in shape, it will be understood that this need not be the case. An interior-facing portion of the adapter body 372 (with respect to when the second adapter 370 is assembled to the container 300) is configured to be received within a channel 337 defined by the interior wall 336 of the insert 330. The sealing engagement between the inner wall 336 and the adapter body 372 is formed by the provision of a ring-shaped seal 380 provided in a circumferential groove 382 in the adapter body 362 .

[0111] As best shown in FIG. 20 , the inner wall 336 is angled relative to the longitudinal axis of the insert 330. Specifically, the inner wall 336 tapers slightly inward, thereby slightly reducing the inner diameter of the channel 337. The inner wall 336 may be angled between approximately 1° and 89° relative to the longitudinal axis of the insert 330 (it will be apparent that in this embodiment, the angle is closer to the lower end of this range). Providing an angled inner wall 336 is advantageous because it accommodates the substantially radial load imparted by the seal 380 and the adapter body 362 when the adapter body 362 is received within the channel 337, thereby forming a suitable sealing engagement between the adapter body 362 and the insert 330. However, it will be understood that in some embodiments, an end seal may be formed, whereby the end seal imparts a substantially axial load on the inner wall 336.

[0112] In another embodiment, instead of angling the entire inner wall 336, only a portion of the inner wall 336 may be angled, as shown in Figure 21. In this case, a chamfered edge 339 is provided, which provides a slight inward taper. It will be appreciated that this embodiment may also be utilized in an end seal scenario, whereby the end seal imparts a substantially axial load on the inner wall 336.

[0113] 17, the second adapter 370 is further configured to operably engage with the first adapter 360. As shown, the upper engagement surface 365 of the first adapter 360 is configured to abut against the lower engagement surface 375 of the second adapter 370. Furthermore, it will be appreciated that a portion of the inner surface of the adapter body 362 also engages a portion of the outer surface of the adapter body 372 when the first adapter 360 and the second adapter 370 are assembled together.

[0114] Nozzle 350 is configured to allow assembly of closure 390 thereto. Closure 390 is configured to prevent fluid communication between the interior of vessel 300 and an environment external to vessel 300. Closure 390 operably engages both first adapter 360 and second adapter 370. In the illustrated embodiment, closure 390 is bolted to first adapter 360 and second adapter 370. When assembled to nozzle 350, closure 390 operably engages flanged end 374 of second adapter 370, and when closure 390 is in the closed position shown in FIG. 17 , its radially outer portion abuts an upper engagement surface of flanged end 374. Other components may be provided to facilitate removal of the closure 390, including allowing the closure 390 to be attached to the nozzle 350 and moving the closure 390 from a closed position to an open position (such as providing a suitable hinge 692 shown on the closure 690 in FIG. 22). Thus, the nozzle 350 is configured to facilitate a suitable fluidly sealed connection between the container 300 and the closure 390.

[0115] FIG. 17 (and FIG. 20) provide an example of how to implement a suitable personnel passage opening for vessel 300.

[0116] Reference is now made to Figure 18, which depicts the nozzle 450 of the vessel 400 formed from component parts. The embodiment of Figure 17 is very similar to the embodiment of Figure 18, except for the overall size of the respective inserts and nozzles. Figure 18 provides an example of how to implement a suitable cleaning hatch for the vessel 400, which is typically of a smaller size relative to the personnel passage of Figure 17.

[0117] Reference is now made to FIG. 19, which depicts a nozzle 550 of a container 500 formed from component parts. The embodiments of FIGS. 17 and 18 are very similar to the embodiment of FIG. 19, except for the overall size of the respective inserts and nozzles, as well as some of the specific components. Unlike the embodiments of FIGS. 18 and 19, which provided examples of how to incorporate a closure into a container, the embodiment of FIG. 19 is directed to incorporating an instrument, such as a sensor or probe 590. To this end, the configuration of the first adapter 560 is significantly different from that of the second adapter 570, which remains substantially similar in form to the second adapter of the previous embodiment. The first adapter 560 is in the form of a substantially ring-shaped flange 562, which is attached to the container 500 using adhesive or other attachment means and a flange nut 582. The sensor 590 is bolted to the nozzle 550, with the bolts passing through the second adapter 570, the first adapter 560, and the flange nut 582. It will be appreciated that the nozzle 550 and insert 530 are typically of a smaller size for the personnel passageway of FIG. 17 and the cleaning hatch of FIG. [Example]

[0118] An example of a suitable method for producing hollow composite container 10 will now be described, however, it will be understood that alternative methods may also be used.

[0119] The method includes preparing a hollow mold for producing a hollow composite container. In this embodiment, this involves the suitable preparation of a plurality of hollow mold elements that, when assembled together, form the mold for the entire hollow composite container. In this example, the hollow mold element includes a generally cylindrical section and two generally hemispherical end sections. The generally cylindrical section includes a structure that protrudes away from the interior of the mold, the structure being in the form of a nozzle mold portion. The nozzle mold portion may be an integrally formed part of the respective hollow mold element, or the nozzle mold portion may be formed from one or more separate components that can be suitably secured to the respective hollow mold element. The hollow mold elements may be formed substantially from a steel frame.

[0120] The fibrous material is held to the interior surface of each hollow mold element, including the nozzle structure (if applicable), by suitable fastening means, e.g., a suitable fastening device. In this example, ceramic fibers are used. While only one fibrous material is applied to the interior surface of each hollow mold element, it will be understood by those skilled in the art that more fibrous materials can be used during this stage of the process (e.g., by adhering additional fibrous materials to previous fibrous materials). Furthermore, the specifically mentioned fibrous materials used should be taken as merely exemplary, as alternative fibrous materials can be used in this process. It is not necessary to have the same arrangement and type of fibrous material fastened to each hollow mold element, but this is preferred in forming a homogeneous and consistent hollow composite container.

[0121] Once each of the hollow mold elements is prepared, they are suitably assembled and secured together to form the entire hollow composite container mold, and the assembled mold is then inserted into a rotational molding apparatus.

[0122] An example was demonstrated by placing approximately 75 kg of polyethylene powder into a rotational molding apparatus prior to closure. Gas pressure is used to hold the fiber material layer against the interior surface of the entire composite container while the mold is rotated and undergoes conventional rotational mold heating. This is achieved by supplying a gas flow inside the rotational molding apparatus, thereby applying a pressure differential across the fiber material, forcing it against the interior surface of the mold.

[0123] Throughout the rotomolding process, various rotomolding parameters are considered and varied throughout the process to produce a suitable hollow composite container. These parameters include: Mold temperature and heating method; · rotational speed of the rotational molding device (around the longitudinal axis); · Inclination speed of the rotational molding device (around the horizontal axis); · Tilt angle - the maximum angle reached by the rotation of the mold device around its horizontal axis relative to its longitudinal axis; Pressure—pressure within the mold to hold the fiber layer against the interior surface of the mold and to help maintain contact between the molten polyethylene and the fiber layer; and Timing - the amount of time a particular parameter is held.

[0124] Throughout the process, care is taken in adjusting the rotational molding equipment temperature set point, mold temperature, and pressure to ensure that a suitable "lay-up" of polyethylene is established on the interior surfaces of the mold, particularly in the nozzle mold section. As previously mentioned, the formation of the nozzle mold is carefully designed to ensure that the contact time between the polyethylene and the nozzle mold section is sufficient to produce a molded nozzle of suitable structural integrity within the hollow composite container that is produced.

[0125] Once the polyethylene is suitably melted and dispersed, the set temperature of the rotational molding machine is reduced, the heat is turned off, and the mold is allowed to cool, solidifying the polyethylene. When the temperature measured within the mold is suitably low (and well below the melting point of the polyethylene powder), pressure is released via the outlet valve. Toward the end of the process, rotation of the rotational molding machine about both the longitudinal and lateral axes is stopped. The hollow thermoplastic polymer / fiber material composite container, with a structure (e.g., a nozzle) protruding away from the interior of the container, can then be removed from the mold. Note that the nozzle mold structure is adapted to include a back split in the plane subtended by the axial and radial directions of the nozzle mold section to ensure proper removal of the container.

[0126] Visual inspection of the container showed that the fibrous layer was firmly adhered to the polyethylene in parts and that the polyethylene had wetted into the fibrous layer, although not completely.

[0127] The next step in the process involves reinforcing the nozzle-containing vessel by applying a plurality of filaments selected from one or more of carbon, glass, aramid, and basalt filaments to the exterior of the hollow thermoplastic polymer / fiber material composite vessel, the plurality of filaments being at least partially wetted with one or more thermosetting polymers prior to application. Thus, the hollow composite vessel is formed with increased strength and rigidity. The fibrous layer of the hollow thermoplastic polymer / fiber material composite vessel facilitates bonding of the reinforcing layer thereto, thereby resulting in the fibrous material being at least partially wetted with both one or more thermoplastic polymers and one or more thermosetting polymers.

[0128] An exemplary method will now be described for an embodiment in which the nozzle is formed from component parts. After applying the filament layer, a hole is drilled through the container in the area around the nozzle / insert. An adhesive is then used to attach a first adapter. A second adapter is then provided, the lower portion of which is received within the channel of the insert and sealingly engages therewith, thereby creating a nozzle formed from component parts. A closure can then be bolted to the nozzle.

[0129] It will be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or apparent from the text or drawings, all of which different combinations constitute various alternative aspects of the present disclosure.

Claims

1. 1. A hollow rotomolded product having an interior wall defining an interior of the product and an integrally formed structure with the interior wall, the integrally formed structure projecting away from the interior of the product, the product being formed from a first layer comprising one or more thermoplastic polymers and a second layer comprising one or more fibrous materials.

2. The hollow rotomolded product of claim 1 , wherein the one or more fibrous materials are at least partially infiltrated with the one or more thermoplastic polymers.

3. 3. The hollow rotomolded product of claim 1 or 2, wherein the structure is configured to allow fluid communication between the interior of the product and an environment external to the product.

4. The hollow rotomolded product of claim 3 , wherein the structure includes one or more nozzles.

5. 5. The hollow rotomolded product of claim 4, wherein the or each nozzle comprises a nozzle body having, at or towards a first end thereof, a nozzle base formed with the interior wall of the product, and at or towards a second end thereof, a nozzle opening configured to allow fluid communication between the interior of the product and the environment exterior to the product.

6. 6. A hollow rotomoulded product according to claim 4 or 5, wherein the or each nozzle includes a substantially curved base transition portion between the inner wall of the product and the nozzle, thereby defining a smooth transition profile between the inner wall of the product and the nozzle.

7. 7. The hollow rotomolded product of claim 6, wherein the radius of curvature of the base transition portion ranges from about 1 mm to about 1000 mm.

8. 8. A hollow rotomoulded product according to claim 5, or claim 6 or 7 when dependent on claim 5, wherein the or each nozzle includes a flared region adjacent the nozzle opening, whereby the diameter of the flared region is greater than the diameter of the nozzle body.

9. The hollow rotomolded product of claim 8 , wherein the flared region includes a flanged end configured to facilitate connection of one or more components to the product.

10. 10. A hollow rotomoulded product according to claim 5, or any one of claims 6 to 9 insofar as it is dependent on claim 5, wherein the or each nozzle base is formed tangent to a main wall of the product.

11. 10. A hollow rotomoulded product according to claim 5, or any one of claims 6 to 9 insofar as it is dependent on claim 5, wherein the product comprises one or more recesses oriented towards the interior of the product, and the or each nozzle base is formed in a respective recess.

12. 12. The hollow rotomoulded product of claim 11, wherein the or each nozzle resides substantially within its respective recess.

13. 10. A hollow rotomoulded product according to claim 5, or any one of claims 6 to 9 when dependent on claim 5, wherein the product includes one or more protrusions directed away from the interior of the product, and the or each nozzle base is formed on a respective protrusion.

14. A hollow rotomoulded product according to any one of claims 4 to 13, wherein the product includes reinforcement material to increase the strength and / or rigidity of the or each nozzle.

15. 15. The hollow rotomolded product of claim 14, wherein the or each nozzle is reinforced with a fiber-reinforced polymer and one or more thermosetting polymers, the fiber-reinforced polymer and the one or more thermosetting polymers being disposed on the second layer around the nozzle, and the one or more fiber materials being at least partially infiltrated with both the one or more thermoplastic polymers and the one or more thermosetting polymers.

16. 10. The hollow rotomolded product of any one of the preceding claims, wherein the one or more thermoplastic polymers in the first layer comprise one or more of an ethylene homopolymer, an ethylene copolymer, a propylene homopolymer, a propylene copolymer, a fluoropolymer, a polyvinyl chloride, a polyvinylidene chloride, a polyaryletherketone, and a polyamide.

17. 17. The hollow rotomolded product of claim 1, wherein the one or more fibrous materials in the second layer comprise one or more of glass fibers, carbon fibers, and basalt fibers, or precursors thereof.

18. 18. The hollow rotomolded product of any one of claims 1 to 17, wherein the product includes a third layer comprising a plurality of filaments selected from one or more of carbon, glass, aramid, and basalt filaments and one or more thermosetting polymers, the second layer being disposed between the first layer and the third layer, and the one or more fibrous materials being at least partially infiltrated with both the one or more thermoplastic polymers and the one or more thermosetting polymers.

19. 19. The hollow rotomolded product of claim 15 or 18, wherein the one or more thermosetting polymers of the third layer include one or more of vinyl esters, bismaleimides, polyesters, polyacrylates, epoxies, and polyurethanes.

20. 20. The hollow rotomolded product of any one of claims 1 to 19, wherein an interior wall, or a portion of an interior wall, of at least one of the one or more nozzles is angled relative to a longitudinal axis of the nozzle, such that a channel defined by the interior wall or angled portion is wider at an exterior-facing end of the channel.

21. 22. The hollow rotomolded product of claim 21, wherein the angled interior wall or the angled portion defines a sealing surface configured to engage a sealing device.

22. 22. A hollow rotomoulded product according to any preceding claim, wherein the or each nozzle is configured to receive one or more component parts forming one or more respective nozzles of the product.

23. 21. The hollow rotomolded product of claim 20, wherein the one or more component parts include a first adapter configured to connect to a respective one of the nozzles, the first adapter including a flanged end, the first adapter configured to facilitate connection of an external component to the product.

24. 24. The hollow rotomolded product of claim 23, wherein the one or more component parts include a second adapter configured to connect to a respective one of the nozzles, the second adapter including a flanged end, the second adapter configured to operably engage with the first adapter.

25. 25. The hollow rotomolded product of claim 24 when dependent on claim 20 or 21, wherein the second adapter is configured to be at least partially received within a channel of the nozzle body, the second adapter being in sealing engagement with the angled inner wall or the angled portion, and a sealing device can be received between the second adapter and the angled inner wall or the angled portion.

26. 26. The hollow rotomolded product of claim 25, further comprising a closure for preventing fluid communication between the interior of the product and the environment exterior to the product.

27. The hollow rotomoulded product of any one of claims 1 to 26, wherein the product is a hollow composite container.

28. 1. A method for producing a hollow composite container, said method comprising: applying one or more fibrous materials to an interior surface of a hollow mold, the hollow mold including structures that protrude away from the interior of the mold; heating and rotating the hollow mold in the presence of one or more thermoplastic polymers within the hollow mold to melt the thermoplastic polymers and at least partially infiltrate the fibrous material; cooling the mold to solidify the thermoplastic polymer; and removing the hollow thermoplastic polymer / fiber material composite container from the mold, the hollow thermoplastic polymer / fiber material composite container having structures protruding away from the interior of the container.

29. One or more of the following steps: applying a plurality of filaments selected from one or more of carbon, glass, aramid, and basalt filaments to the exterior of the hollow thermoplastic polymer / fiber material composite container, wherein prior to application, the plurality of filaments are at least partially wetted with one or more thermosetting polymers; applying a plurality of filaments selected from one or more of carbon, glass, aramid, and basalt filaments to the exterior of the hollow thermoplastic polymer / fiber material composite container, followed by applying one or more thermosetting polymers; 30. The method of claim 28, further comprising applying one or more thermosetting polymers to the exterior of the hollow thermoplastic polymer / fiber material composite container, followed by applying a plurality of filaments selected from one or more of carbon, glass, aramid, and basalt filaments.

30. 30. The method of claim 29, wherein the one or more thermosetting polymers comprise one or more of vinyl esters, bismaleimides, polyesters, polyacrylates, epoxies, and polyurethanes.

31. 31. The method of any one of claims 28 to 30, wherein applying one or more fiber materials to the interior surface of the hollow mold comprises applying one or more of glass fiber, carbon fiber, and basalt fiber, or precursors thereof.

32. 32. The method of any one of claims 28 to 31, wherein the one or more thermoplastic polymers comprise one or more of an ethylene homopolymer, an ethylene copolymer, a propylene homopolymer, a propylene copolymer, a fluoropolymer, polyvinyl chloride, polyvinylidene chloride, a polyaryletherketone, and a polyamide.

33. 33. The method of any one of claims 28 to 32, further comprising drilling one or more holes through the structure of the container and into the interior of the container.

34. 34. The method of any one of claims 28 to 33, wherein the structure of the container is configured to allow fluid communication between the interior of the container and an environment external to the container.

35. 35. The method of any one of claims 34, wherein the structure of the container includes one or more nozzles.

36. 36. A method according to any one of claims 28 to 35, wherein the hollow mould includes one or more protrusions directed towards the interior of the mould, the or each protrusion forming a respective recess in the formed container, and the structure protruding away from the interior of the mould extending into the protrusions, whereby the base of the or each nozzle is formed in the respective recess in the formed container.

37. 36. A method according to any one of claims 28 to 35, wherein the hollow mould includes one or more protrusions directed away from the interior of the mould, the or each protrusion forming a respective protrusion in the formed container, and the structure protruding away from the interior of the mould extending from the protrusion, whereby the base of the or each nozzle is formed on the respective protrusion in the formed container.

38. 38. A method according to any one of claims 28 to 37, further comprising reinforcing the or each nozzle with a fibre reinforced polymer and one or more thermosetting polymers, wherein the fibre reinforced polymer and the one or more thermosetting polymers are disposed on the one or more fibrous materials around the nozzle, the one or more fibrous materials being at least partially infiltrated with both the one or more thermoplastic polymers and the one or more thermosetting polymers.

39. 39. The method of any one of claims 28 to 38, wherein the structures of the hollow mold that protrude into the interior of the mold are one or more nozzle mold parts.

40. 40. The method of any one of claims 28 to 39, wherein the hollow mold further comprises protrusions disposed around the periphery of the structure that protrude into the interior of the mold, whereby the hollow thermoplastic polymer / fiber material composite container comprises recesses extending through an outer wall of the thermoplastic polymer / fiber material composite, the recesses being disposed around the periphery of the structure.

41. 41. A method according to any one of claims 28 to 40, wherein an inner wall, or a portion of an inner wall, of at least one of the one or more nozzles is angled relative to a longitudinal axis of the nozzle, such that a channel defined by the inner wall or angled portion is wider at an outer facing end of the channel.

42. 42. The method of claim 41, wherein the angled inner wall or the angled portion defines a sealing surface configured to engage a sealing device.

43. 43. The method of claim 29, or any one of claims 30 to 42 when dependent on claim 29, further comprising the step of drilling or otherwise creating one or more holes through the container, the step of creating holes through the container being undertaken after the step of applying the filament layer, the holes being configured to receive one or more component parts that form a nozzle of the product.

44. 44. The method of claim 43, further comprising assembling the one or more component parts from the nozzle of the vessel.

45. 45. The method of claim 44, wherein the assembling step includes the steps of connecting a first adapter to each one of the nozzles and connecting a second adapter to each one of the nozzles.

46. 46. ​​The method of claim 45, wherein the assembling step includes providing a sealing device between the nozzle and the second adapter before connecting the second adapter to the nozzle.

47. 47. The method of any one of claims 28 to 46, further comprising providing a closure to prevent fluid communication between the interior of the container and the environment external to the container.

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