System and process for the continuous manufacturing of an elongate composite part

Abstract

A system (100) for the continuous manufacturing of an elongate composite part (EF) comprising a bundle of multifilament fibers impregnated with a composition based on a polymerizable material, the system (100) comprising, in the direction of travel of the bundle of multifilament fibers: - at least one module (110) for preparing a monofilament impregnated with polymerizable material; - a first radiation device (117) that comprises a first ultraviolet light source (117a) through which the multifilament fiber bundle impregnated with polymerizable material travels and which is configured to carry out a partial polymerization to form a pre-polymerized monofilament (E2); and - a second radiation device (118) that is separate and different from the first radiation device (117) and comprises a second at least infrared light source (118a) through which the pre-polymerized monofilament (E2) travels and which is configured to carry out a final polymerization of the pre-polymerized monofilament (E2) to form a final composite monofilament (EF).

Description

[0001] DESCRIPTION

[0002] TITLE: Installation and process for the continuous manufacturing of an elongated composite element

[0003] The present invention relates to the field of continuous manufacturing of elongated composite materials produced by impregnation of a polymerizable composition of multifilament fibers.

[0004] More particularly, the present invention relates to an installation and a method for manufacturing composites in the form of single strands comprising continuous, unidirectional multifilament fibers embedded in a polymerizable resin.

[0005] The present invention relates more particularly, but not exclusively, to the manufacture of single strands of glass resin composite, acronym "CVR", having high mechanical properties.

[0006] Such elongated composite materials can be used in the form of composite reinforcements which can be used, in particular, for the reinforcement of semi-finished products or finished rubber articles such as vehicle tires, for example of the pneumatic or non-pneumatic type, or in concrete reinforcement applications.

[0007] Tire designers have long been looking for low-density textile or composite reinforcements that can be a good and effective substitute for conventional metal wires or cables, particularly in order to reduce the weight of these tires and also to overcome potential corrosion problems.

[0008] We know the document EP 1 174 250 - Al which describes a process for the continuous manufacture of CVR monostrands comprising the following steps:

[0009] - making an arrangement of glass fibers and driving this arrangement in a direction of advancement; - degassing the arrangement of fibers by the action of vacuum in a vacuum chamber;

[0010] - at the outlet of the vacuum chamber, after degassing, pass through an impregnation chamber filled with resin so as to impregnate said arrangement of fibers with a resin in the liquid state to obtain an impregnation containing the fibers and the resin;

[0011] - passing said impregnated material through a calibration die having a predefined surface section and shape, to impose a single-strand shape on it; and

[0012] - downstream of the calibration line, in an irradiation chamber, stabilize, solidify the single strand by photopolymerization of the resin in a UV and / or IR radiation device.

[0013] Experience shows, however, that the CVR monofilaments described can still be improved.

[0014] Generally, with reference to figure 1, a device 1 for manufacturing a single strand of glass-resin composite comprises one or more reels 10 containing glass fibers 11 in the form of multifilaments and continuously unwound by driving along the arrow F by a driving means (not shown), so as to produce an arrangement 12 of these fibers 11.

[0015] The arrangement 12 then passes through a vacuum chamber 13 arranged between an inlet nozzle 13a and a separation nozzle 13b and an impregnation chamber 14 downstream of the separation nozzle 13b and filled with impregnation composition 15 based on a curable resin. The device 1 further comprises a calibration die

[0016] 16 at the outlet of the impregnation chamber 14 so as to obtain a single strand 17 and a radiation device 18 comprising, for example, a protection tube 18a through which the composite single strand circulates

[0017] 17 and a plurality of UV and / or IR irradiators 18b in line in order to obtain a polymerized monostrand 19.

[0018] In this regard, reference may be made to document FR 3 009 226 - B 1, which describes a process for manufacturing a single strand of glass-resin composite using this type of manufacturing device. However, the core polymerization of the single strand impregnated by UV lamps is not satisfactory.

[0019] Also known is document US 9,970,411-B2 which describes curing techniques in the manufacture of composite products. This document describes a method using a first radiation source capable of emitting infrared radiation and configured to heat a plurality of layers of a composite structure and a second radiation source capable of emitting ultraviolet light and configured to initiate photocuring of the plurality of preheated layers.

[0020] However, this process requires the use of infrared radiation to heat the plurality of layers. Ultraviolet radiation is used to initiate photocuring and does not allow satisfactory polymerization of the layers, particularly at the core.

[0021] It is also known to use UV radiation lamps or UV irradiators with iron-doped mercury vapor that emit UV rays in a broad spectrum ranging from UVC to UVA, infrared rays, acronym "IR" and visible light.

[0022] The exposure time of the impregnated single strand in these mercury vapor UV lamps is 2 to 2.5s for a single strand with a diameter between 0.7 mm and 1.1 mm and the manufacturing speed is between 100 m / min and 120 m / min.

[0023] Typically, in installations using such mercury vapor UV lamps, the impregnated monofilament passes through a tube, usually made of borosilicate glass or quartz glass, to protect the UV bulbs and the mirror system from styrene vapors and resin splashes. These tubes must be removed from the machine and cleaned regularly. The UV lamps are cooled by air, particularly using a ventilation system. In addition, nitrogen is injected into the tubes at the inlet of the UV lamps to reduce the oxygen content, which is a polymerization inhibitor. The nitrogen flow is generally used to evacuate the styrene vapors that are released during polymerization. The evaporation of styrene is all the more significant when the temperature of the impregnated monofilament is high at the start of polymerization. The vapors are, moreover, sucked out of the UV lamps by the ventilation system.

[0024] Mercury vapor UV lamps are particularly expensive and have high energy consumption, which increases the operating cost of the plant. In addition, the energy consumption due to the ventilation system for cooling the lamps significantly increases energy consumption.

[0025] Furthermore, the guaranteed lifespan of mercury vapor UV lamps is limited to approximately 1,000 hours. Beyond this lifespan, the intensity of the mercury vapor UV lamp begins to decrease, requiring regular replacement of these lamps for continuous production.

[0026] Clogging of the tubes by styrene vapors can affect the quality of the product and requires regular cleaning of these tubes.

[0027] In addition, styrene vapors contained in the ventilation system represent a certain risk of explosion. To eliminate the risk of explosion, it is necessary to inject nitrogen into the tubes of the UV lamps to reduce the amount of oxygen. Depending on the quantities, it is also necessary to filter the gaseous fluid contained in these styrene vapors before being released into the atmosphere.

[0028] The amount of UV and IR emitted is given by the spectrum of the mercury vapor UV lamp and it is not possible to adjust the two powers independently. There are mirrors that absorb IR rays to reduce IR rays, but it is not possible to adjust them continuously during testing or production and it is a waste of energy, because the energy absorbed by the mirrors is lost.

[0029] Thus, there is a need to address the above-mentioned drawbacks.

[0030] The invention aims to optimize the polymerization of composite monofilaments in order to reduce energy consumption and the overall operating cost of the installation, to increase the production speed of composite monofilaments and to reduce styrene vapors in composite monofilament manufacturing installations, while maintaining equivalent or superior mechanical properties of the composite monofilament.

[0031] The present invention relates to an installation for the continuous manufacture of an elongated composite element comprising a bundle of multifilament fibers impregnated with a composition based on a polymerizable material.

[0032] The installation comprises, in the direction of advancement of the bundle of multifilament fibers:

[0033] - at least one module for preparing a single strand impregnated with polymerizable material;

[0034] - a first radiation device through which the single strand impregnated with polymerizable material circulates and configured to carry out a partial or intermediate polymerization or pre-polymerization to form a pre-polymerized single strand; and

[0035] - at least one second radiation device, final radiation device, separate and distinct from the first radiation device, through which the pre-polymerized monostrand circulates and configured to carry out a final polymerization of the pre-polymerized monostrand to form a final composite monostrand.

[0036] The first radiation device comprises a first light source with ultraviolet radiation, acronym UV, and the second radiation device comprises a second light source at least with infrared radiation, acronym IR, configured to emit at least one infrared radiation and to complete the polymerization of the pre-polymerized impregnated monostrand.

[0037] By "partial polymerization or pre-polymerization" is meant that the degree of polymerization has not yet reached 95% of complete polymerization.

[0038] Without limitation, the degree of polymerization can be evaluated using a measuring instrument of the “DSC” type, acronym for “Differential Scanning Calorimetry” in English terms. Complete polymerization of the composite is obtained when the degree of polymerization of the polymerizable material is close to 100%, preferably greater than or equal to 95% of complete polymerization.

[0039] Preferably, the second light source is configured to emit only infrared radiation, with a wavelength between 1 pm and 3 um and to complete the polymerization of the pre-polymerized impregnated monostrand.

[0040] By "elongated composite element" is meant a very long composite element comprising a bundle of multifilament fibers embedded in a composition based on a polymerizable material, which is manufactured continuously from one or more supply reels of multifilament fibers to form a bundle which is driven in translation to successively impregnate its fibers with polymerizable material and polymerize the material as the bundle moves.

[0041] By “multifilament fiber” is meant a fiber which comprises several elementary filaments arranged side by side to form a bundle whose elementary fibers are unidirectional while being substantially parallel to each other.

[0042] Multifilament fibers can be chosen from the group consisting of glass, carbon, silica, ceramic, flax, hemp, basalt, cellulose, etc. fibers. These multifilament fibers are used to produce elongated composites made by impregnating the multifilament fibers with a polymerizable composition.

[0043] The polymerizable material may be of the thermosetting type, preferably thermocrosslinkable, preferably of the vinylester type. By polymerizable material is meant a material comprising, by weight, more than 50%, preferably more than 75%, of organic matter and even more preferably more than 90% of organic matter.

[0044] Thus, this material may be a thermopolymerizable polymeric material, for example based on unsaturated polyester, polyepoxide, phenolic derivative, or aminoplast. Preferably, the polymerizable material is crosslinked.

[0045] For example, the polymerizable material is a resin that can be crosslinked by ionizing radiation, and the final polymerization can be easily triggered and controlled by means of an ionizing treatment, for example of the UV type.

[0046] For example, the polymerizable material is a resin that can be crosslinked by ionizing radiation, and the final polymerization can be easily triggered and controlled by means of an ionizing treatment, for example of the UV type.

[0047] The glass transition temperature of the polymerizable material is preferably greater than or equal to 130°C, for example greater than 170°C, preferably greater than or equal to 180°C.

[0048] The separation of the radiation devices, each comprising its own light source, makes it possible to optimize the polymerization of composite monofilaments, by reducing the energy consumption and the overall operating cost of the installation, to increase the production speed of composite monofilaments and to reduce styrene vapors in composite monofilament manufacturing installations, while maintaining equivalent or superior mechanical properties of the composite monofilament.

[0049] Advantageously, the preparation module for an impregnated single strand comprises:

[0050] - a supply device comprising, for example, one or more elementary filament supply reels, configured to form a bundle of multifilament fibers;

[0051] - a vacuum or degassing chamber for the multifilament fiber bundle; and

[0052] - an impregnation chamber filled with a composition based on a polymerizable material and configured to impregnate said degassed multifilament fiber bundle with said composition and form the impregnated monostrand, said impregnation chamber being located downstream of the degassing chamber in the direction of advancement of the multifilament fiber bundle. The vacuum chamber makes it possible to degas the multifilament fiber bundle by the action of the vacuum and thus to reinforce the effectiveness of the subsequent impregnation and above all to guarantee the absence of bubbles inside the final composite monostrand.

[0053] Preferably, the module for preparing an impregnated monostrand comprises a heating device associated with the impregnation chamber and configured to heat the polymerizable material present in said impregnation chamber to a temperature between 50°C and 95°C, preferably between 60°C and 80°C.

[0054] Thus, the impregnated single strand leaves the impregnation chamber at a temperature between 50°C and 95°C, preferably between 60°C and 80°C before passing through the radiation devices. This avoids using an infrared radiation light source upstream of the UV radiation source.

[0055] Generally, the power of the first UV radiation light source is between 1 kW and 50 kW, for a diameter between 0.2 mm and 2.5 mm and a speed between 80 m / min and 200 m / min, preferably between 5 kW and 24 kW for a preferred speed between 100 m / min and 120 m / min and a preferred diameter between 0.7 mm and 1.1 mm.

[0056] For example, the exposure time of the impregnated single strand to the first UV light source is between 0.1 s and 4.5 s, preferably between 0.4 s and 2.3 s.

[0057] According to one embodiment, the first ultraviolet light source comprises a plurality of light-emitting diodes, acronym LED, configured to emit only monochromatic ultraviolet radiation, with a wavelength between 200nm and 405nm, preferably between 365nm and 405nm.

[0058] Preferably, the light-emitting diodes are directed radially towards the impregnated single strand.

[0059] The first LED ultraviolet light source therefore allows radial radiation to be emitted onto the impregnated single strand, with or without reflectors to optimize irradiation. The use of LEDs can reduce the emission of styrene vapors, reduce fouling of the protection tube, and reduce variations in light intensity over time, which allows for more consistent polymerization of the impregnated single strand.

[0060] Furthermore, LEDs have a longer lifespan and lower or similar energy consumption than mercury vapor lamps and can reduce the release of styrene vapors into the atmosphere.

[0061] For example, the power of LEDs is between 1kW and 16kW, preferably between 3 kW and 8 kW for a preferred speed between 100 m / min and 120 m / min and a preferred diameter between 0.7 mm and 1.1 mm.

[0062] For example, the exposure time of the impregnated single strand to the first UV radiation light source comprising LEDs is between 0.1 s and 1.5 s, preferably between 0.3 s and 0.7 s.

[0063] According to another embodiment, the first ultraviolet light source comprises a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet radiation (UV), infrared radiation and visible light.

[0064] For example, the exposure time of the impregnated monostrand to the first UV radiation light source comprising a plurality of mercury vapor lamps is between 0.1 s and 4.5 s, preferably between 0.4 s and 2.3 s at a power between 4 kW and 50 kW, preferably between 5 kW and 24 kW.

[0065] For example, the second infrared light source comprises a plurality of infrared lamps directed radially towards the impregnated monostrand.

[0066] For example, the second infrared light source is configured to emit only infrared radiation, with a wavelength between 1 pm and 3 pm. For glass fibers, a second IR source with a wavelength equal to 1 pm will be preferred. The exposure time of the pre-polymerized impregnated single strand to the second IR light source is between 0.6s and 10s, preferably between 2s and 4s.

[0067] The power of the second IR light source is between 3kW and 50kW, preferably between 8 kW and 24 kW.

[0068] According to another embodiment, the second light source at least with infrared radiation comprises a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet radiation (UV), infrared radiation and visible light.

[0069] According to another embodiment, the installation comprises a third radiation device arranged between the first radiation device and the second radiation device and comprising a third light source, for example ultraviolet radiation and / or infrared radiation, configured to polymerize at a second pre-polymerization the single strand pre-polymerized by the first radiation device.

[0070] For example, the third light source comprises a plurality of light-emitting diodes configured to emit only monochromatic ultraviolet radiation with a wavelength between 200nm and 405nm, preferably between 365nm and 405nm, or a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet radiation, infrared radiation and visible light, or a light source configured to emit infrared radiation alone.

[0071] In the case of a third radiation device, the first radiation device is configured to polymerize the impregnated monostrand at a first pre-polymerization and deliver an impregnated monostrand at a first pre-polymerization, the third radiation device is configured to polymerize the pre-polymerized monostrand at a second pre-polymerization and deliver an impregnated monostrand, and the second radiation device is configured to complete the polymerization of the pre-polymerized monostrand at the second polymerization. By "first pre-polymerization" is meant that the degree of polymerization of the impregnated monostrand has reached between 10% and 50%.

[0072] By "second pre-polymerization" we mean that the degree of polymerization of the pre-polymerized impregnated single strand has reached between 50% and 80%.

[0073] Generally, it could be provided that the installation comprises one or more intermediate radiation devices arranged between the first UV radiation device and the final IR radiation device.

[0074] According to one embodiment, the installation further comprises a calibration die or nozzle at the outlet of the impregnation chamber so as to obtain a single strand impregnated with polymerizable material.

[0075] The sizing nozzle is configured to shape the bundle of multifilament fibers exiting the impregnation chamber to form an impregnated monostrand.

[0076] Alternatively, any other device could be provided allowing the shaping of the impregnated single strand before polymerization in the radiation devices.

[0077] For example, the installation comprises a translational drive device configured to drive the bundle of multifilament fibers in translation to successively carry out degassing, impregnation of its fibers with polymerizable material and polymerization of the material as the bundle moves.

[0078] The vacuum chamber and the impregnation chamber, the calibration nozzle, the first radiation device and the second radiation device are arranged along the same axis corresponding to the longitudinal axis of the installation.

[0079] According to a second aspect, the invention relates to a method for the continuous manufacture of an elongated composite element comprising a bundle of multifilament fibers impregnated with a composition based on a polymerizable material forming an impregnated single strand, comprising the following successive steps: - preparation of a single strand impregnated with polymerizable material; - driving said single strand impregnated with polymerizable material to subject it in the direction of advance to:

[0080] - passing the impregnated single strand through a first radiation device to carry out partial polymerization of said impregnated single strand and obtain a pre-polymerized single strand; and at least

[0081] - passing the pre-polymerized single strand through a second radiation device, separate and distinct from the first radiation device, to carry out a final polymerization of said pre-polymerized single strand and obtain said elongated composite element.

[0082] Said first radiation device is configured to emit ultraviolet radiation and the second radiation device is configured to emit at least one infrared radiation and to terminate the polymerization of the pre-polymerized impregnated monostrand.

[0083] Preferably, the second radiation device is configured to emit only infrared radiation, for example with a wavelength between 1 pm and 3 pm.

[0084] The step of preparing a single strand impregnated with polymerizable material comprises the following successive steps:

[0085] - a step of feeding elementary filaments to form a bundle of multifilament fibers,

[0086] - a degassing step, in a vacuum chamber, of the rectilinear bundle of multifilament fibers and

[0087] - an impregnation step during which the bundle of multifilament fibers is impregnated with a composition based on a polymerizable material contained in an impregnation chamber filled with said composition.

[0088] The impregnation chamber is associated with a heating device configured to heat the polymerizable material to a temperature between 50°C and 95°C, preferably between 60°C and 80°C.

[0089] Thus, the impregnated monostrand leaves the impregnation chamber at a temperature between 50°C and 95°C, preferably between 60°C and 80°C before passing through the radiation devices. Advantageously, the exposure time of the impregnated monostrand to the first ultraviolet light source is between 0.1 s and 4.5 s. with a power of the first UV light source is between 1 kW and 50 kW and the exposure time of the pre-polymerized impregnated monostrand to the second infrared radiation light source is between 1 s and 10 s with a power of the second IR light source is between 3 kW and 50 kW.

[0090] Advantageously, the composite monostrand is manufactured from a bundle of multifilament fibers with a small diameter of between 0.2 mm and 2.5 mm, preferably between 0.7 mm and 1.1 mm.

[0091] Indeed, the association of an infrared radiation light source downstream of a UV radiation light source is necessary to complete the polymerization of a small diameter single strand, due to the faster cooling of a bundle of small diameter multifilament fibers compared to a bundle of large diameter multifilament fibers, between 10mm and 30mm.

[0092] Other aims, characteristics and advantages of the invention will appear on reading the following description, given solely by way of non-limiting example, and made with reference to the appended drawings in which:

[0093] [Fig. l] very schematically represents an installation for manufacturing a composite element according to the state of the art;

[0094] [Fig.2] very schematically represents an installation for manufacturing a composite element according to a first embodiment of the invention

[0095] [Fig.3] very schematically represents an installation for manufacturing a composite element according to a second embodiment of the invention; and

[0096] [Fig.4] is a flowchart illustrating certain steps in the process of manufacturing a composite element by an installation according to Figure 2.

[0097] Figure 2 schematically illustrates an installation 100 for manufacturing a very long, elongated EF composite element.

[0098] By "elongated composite element" is meant a very long composite element comprising a bundle of multifilament fibers embedded in a composition based on a polymerizable material, which is manufactured continuously from one or more supply reels of multifilament fibers Fi_0 to form a bundle which is driven in translation along the arrow F to successively impregnate its fibers with polymerizable material and polymerize the material as the bundle moves.

[0099] By “multifilament fiber” is meant a fiber which comprises several elementary filaments Fi arranged side by side to form a bundle whose elementary fibers are unidirectional while being substantially parallel to each other.

[0100] Multifilament fibers can be chosen from the group consisting of glass, carbon, silica, ceramic, flax, hemp, basalt, cellulose, etc. fibers. These multifilament fibers are used to produce elongated composites made by impregnating the multifilament fibers with a polymerizable composition.

[0101] The polymerizable material may be of the thermosetting type, preferably thermocrosslinkable, preferably of the vinylester type. By polymerizable material is meant a material comprising, by weight, more than 50%, preferably more than 75%, of organic matter and even more preferably more than 90% of organic matter.

[0102] Thus, this material may be a thermopolymerizable polymeric material, for example based on unsaturated polyester, polyepoxide, phenolic derivative, or aminoplast. Preferably, the polymerizable material is crosslinked. For example, the polymerizable material is a resin crosslinkable by ionizing radiation, the final polymerization being able to be triggered and controlled easily by means of an ionizing treatment, for example of the UV type.

[0103] The glass transition temperature Tg of the polymerizable material is preferably greater than or equal to 130°C, for example greater than 170°C, preferably greater than or equal to 180°C.

[0104] In the example illustrated in the figures, the composite element EF is a single strand comprising multifilament fibers embedded in a polymerizable material, such as a thermosetting resin.

[0105] The EF composite monofilament can take any known form, it can be, for example, a cylindrical monofilament of large diameter, for example between 10mm and 30mm or a cylindrical monofilament of small diameter, for example between 0.2 and 2.5mm.

[0106] The elementary filaments, for example, each have an average diameter of between 5 pm and 30 pm.

[0107] The installation of the invention allows, of course, the manufacture of single strands of circular, rectangular, oval, elliptical, tubular cross section, etc.

[0108] As illustrated in Figure 2, the manufacturing installation 100 comprises, in the direction of advancement of the bundle of multifilament fibers according to arrow F:

[0109] - a supply device 1 1 1 comprising here reels 1 12 for supplying elementary filaments Fi_0 to form a bundle of multifilament fibers E0,

[0110] - a vacuum chamber 113 or degassing chamber arranged between an inlet nozzle 113a and a separation nozzle 113b;

[0111] - an impregnation chamber 114 downstream of the vacuum chamber 113 and in particular of the separation nozzle 113b and filled with an impregnation composition 115 based on a polymerizable material;

[0112] - a calibration die 1 16 at the outlet of the impregnation chamber 1 14 so as to obtain a single strand E l impregnated with polymerizable material; - a first polymerization device 1 17 through which the single strand E l impregnated with polymerizable material circulates and configured to carry out a partial or intermediate polymerization to form a pre-polymerized single strand E2;

[0113] - a second final polymerization device 1 18, distinct from the first radiation device 1 17, through which the pre-polymerized monostrand E2 circulates and configured to carry out a final polymerization to form a final composite monostrand EF; and

[0114] - a translational drive device D according to arrow F configured to drive the bundle of multifilament fibers in translation to successively carry out degassing, impregnation of its fibers with polymerizable material and polymerization of the material as the bundle moves.

[0115] The vacuum chamber 113, the impregnation chamber 114, the calibration die 116, the first polymerization device 117 and the second polymerization device 118 are arranged along the same axis corresponding to the longitudinal axis X-X' of the installation 100.

[0116] Generally, the fibers are delivered by one or more reels 1 12, called "rovings" in Anglo-Saxon terms. The bundle, coming from the feeding device 1 1 1 , passes through the installation, advancing in the direction of the arrow F, being set in motion by the drive device D located at the output of the device.

[0117] Each spool 112 can supply a multifilament fiber. If the installation 100 comprises nine multifilament fibers, the supply device 111 comprises nine spools.

[0118] The drive device D is, for example, of the type comprising a motorized traction drum for winding the composite element around its axis or comprising two motorized drums facing each other, spaced apart by a corresponding distance at least equal to the thickness of the composite element and which rotate in opposite directions to drive the composite element EF, by friction, in a translational movement, making it pass into the space located between the two drums. Alternatively, any drive device could be used to set the bundle of multifilament fibers in motion in a direction of advance.

[0119] The vacuum chamber 113 is, in a manner known per se, delimited by an inlet nozzle 113a, rigid, provided with a through orifice and a separation nozzle 113b, rigid, also provided with one or more through orifices located axially opposite the orifice of the inlet nozzle 113a.

[0120] The bundle of multifilament fibers EO is introduced into the vacuum chamber 113 by passing it through the orifice(s) of the inlet nozzle 113a and exits through the through orifice(s) of the separation nozzle 113b.

[0121] The vacuum chamber 1 13 is connected to a vacuum pump (not shown) which maintains a pressure level of approximately 0. lbar in the vacuum chamber 1 13 , despite the passage of the bundle of multifilament fibers EO through the orifice(s) having a diameter greater than that of the bundle of multifilament fibers EO which passes through them.

[0122] The vacuum chamber 1 13 allows the bundle of EO multifilament fibers to be degassed by the action of the vacuum and thus to reinforce the effectiveness of the subsequent impregnation and above all to guarantee the absence of bubbles inside the final composite monostrand.

[0123] After passing through the vacuum chamber 1 13 , the bundle of multifilament fibers EO enters the impregnation chamber 1 14 which is completely full of polymerizable impregnation material, therefore free of air.

[0124] The impregnation chamber 1 14 is an airtight enclosure, delimited by the separation nozzle 1 13b and a final outlet nozzle 1 16, rigid, also provided with a through orifice located axially opposite the orifice of the separation nozzle 1 13b.

[0125] The impregnation chamber 114 is supplied with polymerizable material 115 coming from an external reservoir (not shown) via an inlet pipe 114a, here located in the upper part of said impregnation chamber 114. The impregnation chamber 114 may also comprise, for example on its lower part, a discharge pipe (not shown) for the polymerizable material.

[0126] The impregnation chamber 114 is completely filled with polymerizable material so that the bundle of multifilament fibers exiting the vacuum chamber 113 and passing through it in a linear path is completely impregnated with polymerizable material.

[0127] The impregnation chamber 1 14 is associated with a heating device 1 14b configured to heat the polymerizable material to a temperature between 50°C and 95°C, preferably between 60°C and 80°C.

[0128] Thus, the impregnated single strand leaves the impregnation chamber 1 14 at a temperature between 50°C and 95°C, preferably between 60°C and 80°C before passing through the radiation devices 1 17, 1 18.

[0129] The calibration die 1 16 here comprises a calibration nozzle configured to shape the bundle of multifilament fibers exiting the impregnation chamber 1 14 to form a single strand of impregnated multifilament fibers E l .

[0130] Alternatively, any other device could be provided allowing the shaping of the impregnated single strand E l before polymerization in the radiation devices 1 17, 1 18.

[0131] The first polymerization device 1 17 comprises a first ultraviolet radiation light source 1 17a, with the acronym UV.

[0132] The first ultraviolet light source 1 17a comprises, for example, a plurality of light-emitting diodes (not shown), acronym LED, preferably directed radially towards the single strand of impregnated multifilament fibers E l.

[0133] The first ultraviolet radiation light source 1 17a with LEDs is configured to emit only monochromatic ultraviolet radiation, the available wavelengths of which are as follows: 365, 385, 395, 405nm, and more generally between 200nm and 405nm. In a non-limiting manner, the first radiation device 1 17 may comprise a protective tube (not referenced) for the impregnated single strand of multifilament fibers E l which enters the first radiation device 1 17. The protective tube is, for example, made of borosilicate glass or quartz glass, through which the single strand E l circulates during formation, this tube may be traversed by a current of inert gas, preferably nitrogen.

[0134] The first 1 17a LED ultraviolet light source therefore makes it possible to emit radial radiation onto the single strand of impregnated multifilament fibers E l , with or without reflectors to optimize irradiation.

[0135] The use of LEDs can reduce styrene vapors, reduce fouling of the protection tube, and reduce variations in light intensity, which allows for more consistent polymerization of multifilament fibers.

[0136] Furthermore, LEDs have a longer lifespan and lower or similar energy consumption than mercury vapor lamps and release less styrene vapors into the atmosphere.

[0137] According to another embodiment, the first ultraviolet light source comprises a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet radiation (UV), infrared radiation and visible light.

[0138] For example, the exposure time of the impregnated single strand to the first UV radiation light source comprising a plurality of mercury vapor lamps is between 0.1 s and 4.5 s, preferably between 0.4 s and 2.3 s, at a power between 1 kW and 50 kW, preferably between 5 kW and 24 kW.

[0139] The first polymerization device 117 is configured to start the photopolymerization of the impregnated multifilament fiber monostrand E1 and deliver a pre-polymerized impregnated monostrand E2.

[0140] The UV rays from the first radiation device 1 17 are absorbed by the photoinitiators, which initiates the polymerization of the resin. It is important that the wavelength or spectrum of the first UV radiation light source is matched to the photoinitiator.

[0141] By "partial polymerization or pre-polymerization" is meant that the degree of polymerization of the multifilament fiber bundle has not reached 95% of complete polymerization.

[0142] Without limitation, the degree of polymerization can be assessed using a “DSC” type measuring instrument, an acronym for “Differential Scanning Calorimetry” in English terms.

[0143] Generally, the exposure time of the impregnated multifilament fiber monostrand E l to the first UV light source 1 17a is between 0.1 s and 4.5 s.

[0144] Generally, the power of the first UV 1 17a light source is between 1kW and 50kW.

[0145] For example, when the first light source comprises LEDs, the power of the LEDs is between 1kW and 16kW, preferably between 3kW and 8kW.

[0146] For example, the exposure time of the impregnated single strand to the first UV radiation light source comprising LEDs is between 0.1 s and 1.5 s, preferably between 0.3 s and 0.7 s.

[0147] The second final radiation device 1 18 comprises a second infrared radiation light source 1 18a, acronym IR, configured to terminate the polymerization of the pre-polymerized impregnated monostrand E2.

[0148] Complete polymerization of the composite is obtained when the degree of polymerization of the polymerizable material is close to 100%, preferably greater than or equal to 95% when the composite is measured with a DSC type device.

[0149] The second infrared radiation light source 1 18a comprises, for example, a plurality of infrared lamps (not shown), preferably directed radially towards the impregnated single strand E l .

[0150] The second infrared light source 1 18a is configured to emit only infrared radiation, with a wavelength between 1 pm and 3 pm. For glass fibers, a second IR source with a wavelength equal to 1 pm will be preferred.

[0151] The exposure time of the pre-polymerized impregnated monostrand E2 to the second IR light source 1 18a is between 0.6s and 10s, preferably between 2s and 4s.

[0152] The power of the second IR 1 18a light source is between 3 kW and 50 kW, preferably between 8 kW and 24 kW.

[0153] In the embodiment illustrated in FIG. 3, in which the same elements bear the same references, the installation 101 for manufacturing a composite monostrand EF differs only from the embodiment illustrated in FIG. 2 by the fact that the installation 101 comprises a third polymerization device 119.

[0154] The third polymerization device 1 19 comprises a third ultraviolet radiation light source 1 19a, with the acronym UV, arranged between the first radiation device 1 17 and the second radiation device 1 18.

[0155] In one example, the first ultraviolet light source 117a of the first polymerization device 117 comprises a plurality of LEDs and is configured to emit only ultraviolet radiation of wavelength between 200nm and 405nm, preferably between 365nm and 405nm, and the third ultraviolet light source 119a comprises a plurality of mercury vapor lamps and is configured to emit broad spectrum ultraviolet radiation, infrared radiation and visible light.

[0156] It could also be expected that LEDs have different wavelengths from each other.

[0157] Alternatively, it could be provided that the first ultraviolet radiation light source 117a of the first polymerization device 117 comprises a plurality of mercury vapor lamps and is configured to emit broad spectrum ultraviolet radiation UV, infrared radiation and visible light and that the third ultraviolet radiation light source 119a comprises a plurality of LEDs and is configured to emit only ultraviolet radiation with a wavelength between 200nm and 405nm, preferably between 365nm and 405nm.

[0158] Alternatively, it could also be provided that the first ultraviolet radiation light source 117a of the first radiation device 117 comprises a plurality of LEDs configured to emit only ultraviolet radiation with a wavelength between 200nm and 405nm, preferably between 365nm and 405nm and that the third ultraviolet radiation light source 119a comprises a plurality of LEDs and is configured to emit only ultraviolet radiation with a wavelength between 200nm and 405nm.

[0159] The first radiation device 117 is configured to polymerize the impregnated single strand E1 at a first pre-polymerization and deliver an impregnated single strand at a first pre-polymerization E2.

[0160] By "first pre-polymerization" we mean that the degree of polymerization of the impregnated single strand has reached between 10% and 50%.

[0161] The third radiation device 1 19 is configured to polymerize at a second pre-polymerization the pre-polymerized monostrand E2 and deliver an impregnated monostrand at a second pre-polymerization E3.

[0162] By "second pre-polymerization" we mean that the degree of polymerization of the impregnated single strand has reached between 50% and 80%.

[0163] The embodiments illustrated in Figures 2 and 3 are particularly advantageous for manufacturing an EF composite monostrand from a bundle of multifilament fibers of small diameter, for example between 0.2mm and 2.5mm, preferably between 0.7 and 1.1mm.

[0164] Indeed, the association of an infrared radiation light source downstream of a UV radiation light source is necessary to complete the polymerization of a bundle of small diameter multifilament fibers, due to the faster cooling of a bundle of small diameter multifilament fibers compared to a bundle of large diameter multifilament fibers, between 10mm and 30mm.

[0165] As illustrated in Figure 4, the flowchart illustrates the steps of a method 200 for manufacturing an EF composite element by the installation according to Figure 2.

[0166] The manufacturing method 200 comprises a step 201 of preparing a bundle of multifilament fibers impregnated with polymerizable material, a step 205 of calibrating so as to obtain a single strand impregnated with polymerizable material E1, a first step 206 of polymerization in the first radiation device 117 of the single strand impregnated with polymerizable material E1 to carry out a partial or intermediate polymerization or pre-polymerization to form a pre-polymerized single strand E2 and a second step 207 of polymerization in the second radiation device 118 to carry out a final polymerization of the pre-polymerized single strand E2 to form a final composite single strand EF.

[0167] Step 201 of preparing a bundle of multifilament fibers impregnated with polymerizable material comprises the following successive steps:

[0168] - a step 202 of feeding elementary filaments to form a bundle of multifilament fibers E0,

[0169] - a step 203 of degassing, in a vacuum chamber 113, the bundle of multifilament fibers E0 and

[0170] - an impregnation step 204 during which the bundle of multifilament fibers E0 is impregnated with a composition based on a polymerizable material contained in an impregnation chamber 114 filled with said composition.

[0171] After passing through the vacuum chamber 1 13 , the bundle of multifilament fibers E0 enters the impregnation chamber 1 14 which is completely full of polymerizable impregnation material, therefore devoid of air.

[0172] The impregnation chamber 114 is supplied with polymerizable material 115 coming from an external reservoir (not shown) via an inlet pipe 114a, here located in the upper part of said impregnation chamber 114.

[0173] The impregnation chamber 114 is completely filled with polymerizable material so that the bundle of multifilament fibers exiting the vacuum chamber 113 and passing through it in a linear path is completely impregnated with polymerizable material.

[0174] The impregnation chamber 1 14 is associated with a heating device 1 14b configured to heat the polymerizable material to a temperature between 50°C and 95°C, preferably between 60°C and 80°C.

[0175] Thus, the impregnated multifilament fiber bundle leaves the impregnation chamber 1 14 at a temperature between 50°C and 95°C, preferably between 60°C and 80°C before passing through the radiation devices 1 17, 1 18.

[0176] During the first polymerization step 206, the single strand impregnated with polymerizable material E1 is partially polymerized to form a single strand E2 using a first radiation device 117 comprising a first ultraviolet radiation light source 117a, with the acronym UV.

[0177] The first ultraviolet light source 1 17a is identical to that described with reference to Figure 2 and will not be further described here.

[0178] During the second polymerization step 207, the pre-polymerized single strand E2 is polymerized using a second radiation device 118 comprising a second infrared radiation light source, distinct and separate from the first radiation device 117.

[0179] The second infrared light source 118 is identical to that described with reference to FIG. 2 and will not be further described here.

[0180] The installation and the manufacturing method according to the invention are designed to adapt to both existing installations and new installations. The installation and the manufacturing method according to the invention make it possible to obtain elongated composite elements based on multifilament fibers whose shape and dimensions are well controlled and whose mechanical properties are homogeneous, and this over its entire length.

[0181] Furthermore, the installation and the manufacturing method according to the invention make it possible to obtain composite elements having a cross-section of different sizes and this at a high manufacturing rate. For example, for a CVR composite, it is possible to obtain with the method according to the invention, sections having a diameter of between 10 and 30 mm for a rate of approximately 50 m / min.

Claims

CLAIMS 1. Installation (100, 101) for the continuous manufacture of an elongated composite element (EF) comprising a bundle of multifilament fibers impregnated with a composition based on a polymerizable material, the installation (100, 101) comprising, in the direction of advancement of the bundle of multifilament fibers: - at least one module (110) for preparing a single strand impregnated (E1) with polymerizable material comprising: - a feed device (111) configured to form a bundle of multifilament fibers (E0); a degassing chamber (113) for the bundle of multifilament fibers (E0); and - an impregnation chamber (114) filled with a composition based on a polymerizable material and configured to impregnate said degassed bundle of multifilament fibers (E0) with said composition, said impregnation chamber (114) being located downstream of the degassing chamber (113) in the direction of advancement of the bundle of multifilament fibers; - a calibration die (116) at the outlet of the impregnation chamber (114) so ​​as to obtain the impregnated single strand (E1) of polymerizable material; - a first radiation device (117) through which the impregnated single strand (E1) of polymerizable material circulates and configured to carry out a partial polymerization to form a pre-polymerized single strand (E2); and - at least one second radiation device (1 18), separate and distinct from the first radiation device (1 17), through which the pre-polymerized monostrand (E2) circulates and configured to carry out a final polymerization of the pre-polymerized monostrand (E2) to form a final composite monostrand (EF), characterized in that the first radiation device (1 17) comprises a first ultraviolet radiation light source (1 17a) comprising: - either a plurality of light-emitting diodes configured to emit only monochromatic ultraviolet radiation with a wavelength between 200nm and 405nm, - or a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet radiation (UV), infrared radiation and visible light, in that the second radiation device (1 18) comprises a second light source at least with infrared radiation (1 18a) configured to emit only infrared radiation and to complete the polymerization of the pre-polymerized impregnated monostrand (E2) and in that the module (1 10) for preparing an impregnated monostrand comprises a heating device (1 14b) associated with the impregnation chamber (1 14) and configured to heat the polymerizable material present in said impregnation chamber (1 14) to a temperature between 50°C and 95°C.

2. Installation (100, 101) according to any one of the preceding claims, in which the second infrared radiation light source (118a) comprises a plurality of infrared lamps directed radially towards the pre-polymerized impregnated single strand (E2).

3. Installation (101) according to any one of the preceding claims, comprising at least one third radiation device (119) arranged between the first radiation device (117) and the second radiation device (118) and comprising a third light source (119a) with ultraviolet and / or infrared radiation configured to polymerize at a second pre-polymerization the pre-polymerized single strand (E2) by the first radiation device (117).

4. Installation (101) according to claim 8, in which the third light source (119a) comprises a plurality of light-emitting diodes configured to emit only monochromatic ultraviolet radiation with a wavelength between 200nm and 405nm or a plurality of vapor lamps of mercury configured to emit broad spectrum ultraviolet radiation, infrared radiation, and visible light.

5. Method (200) for the continuous manufacture of an elongated composite element (EF) comprising a bundle of multifilament fibers impregnated with a composition based on a polymerizable material, comprising the following successive steps: - preparation of a single strand impregnated (E l ) with polymerizable material a module (1 10) for preparing a single strand impregnated (E l ) with polymerizable material comprising: - a feed device (111) configured to form a bundle of multifilament fibers (E0); a degassing chamber (113) for the bundle of multifilament fibers (E0); and - an impregnation chamber (114) filled with a composition based on a polymerizable material and configured to impregnate said degassed bundle of multifilament fibers (E0) with said composition, said impregnation chamber (114) being located downstream of the degassing chamber (113) in the direction of advancement of the bundle of multifilament fibers; - a calibration die (1 16) at the outlet of the impregnation chamber (1 14) so ​​as to obtain the impregnated single strand (E l ) of polymerizable material; - drive said single strand impregnated with polymerizable material to subject it in the direction of advance to: - passage of the impregnated single strand (E1) into a first radiation device (117) to carry out a partial polymerization of said impregnated single strand (E1) and to obtain a pre-polymerized single strand (E2); said impregnated single strand (E1) present in said impregnation chamber (114) being configured to be heated to a temperature between 50°C and 95°C by a heating device (114b) associated with the impregnation chamber (114) and at least - passing the pre-polymerized single strand (E2) into a second radiation device (118), separate and distinct from the first radiation device (117), to carry out a final polymerization of said pre-polymerized single strand (E2) and obtaining said elongated composite element (EF), said first radiation device (1 17) being configured to emit ultraviolet radiation comprising - either a plurality of light-emitting diodes configured to emit only monochromatic ultraviolet radiation with a wavelength between 200nm and 405nm, - either a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet radiation (UV), infrared radiation and visible light, and the second radiation device (118) being configured to emit only infrared radiation.

6. Method according to claim 5, in which the exposure time of the impregnated single strand (E1) to the first ultraviolet light source is between 0.1 s and 4.5 s with a power of the first UV light source is between 1 kW and 50 kW, and the exposure time of the pre-polymerized impregnated single strand (E2) to the second infrared light source is between 0.6 s and 10 s with a power of the second IR light source is between 3 kW and 50 kW.

7. Method according to claim 5 or 6, in which the composite monostrand (EF) is manufactured from a bundle of multifilament fibers of small diameter between 0.2mm and 2.5mm.

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