A melt impregnation mold and method for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg

Abstract

The invention provides a melt impregnation mold and method for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg, which belongs to the technical field of thermoplastic composite material prepreg preparation. The invention solves the problems of high porosity, low impregnation degree and easy fiber breakage during the preparation process faced by the current fiber reinforced high-viscosity thermoplastic resin prepreg. It includes a top cover assembly and a dipping bottom tank assembly, the top cover assembly includes an upper cover plate, an adjustable height dipping roller and an upper calendering roller, and several adjustable height dipping rollers are evenly arranged on the lower surface of the upper cover plate. The dipping bottom tank assembly includes a U-shaped bottom plate, a fixed height dipping roller and a lower calendering roller, and several fixed height dipping rollers are evenly arranged on the U-shaped bottom plate, and several heating rods are evenly penetrated inside the upper cover plate and the U-shaped bottom plate. The invention creates a product with low porosity, good impregnation degree and no fiber damage, and the dipping pressure and coating angle are adjustable during the application of the dipping mold.

Description

Technical Field

[0001] The invention belongs to the technical field of thermoplastic composite material prepreg tape preparation, and in particular relates to a melt impregnation mold and a method for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg tape. Background Art

[0002] Continuous fiber reinforced thermoplastic composites (FRTP) are gradually replacing thermosetting composites (FRSP) in the field of civil engineering under harsh service environments due to their excellent impact resistance, fatigue resistance, heat resistance and durability, as well as short molding time and secondary processing. Continuous carbon fiber reinforced polyetheretherketone composites (CF / PEEK) have excellent solvent resistance, friction resistance, high temperature resistance and biocompatibility, and are widely used in aerospace, medical, energy, automotive and other fields.

[0003] Although continuous fiber reinforced thermoplastic composites have excellent performance and extremely high application value, there are still deficiencies in the preparation technology, process and equipment in China. Continuous fiber reinforced thermoplastic composites are generally made by molding continuous fiber reinforced thermoplastic composite prepreg tapes (materials), so it is very important to prepare high-quality continuous fiber reinforced thermoplastic composite prepreg tapes (materials). The main reason for the difficulty in preparing continuous fiber reinforced thermoplastic composite prepreg tapes (materials) is that thermoplastic resins such as PEEK have extremely high viscosity and poor fluidity, and it is difficult to achieve good impregnation of the resin melt into the fiber during the preparation process. Therefore, the impregnation mold and process are the key to preparing continuous fiber reinforced thermoplastic composite prepreg tapes (materials) with high impregnation degree and low porosity, and it is also a technical problem that my country urgently needs to break through.

[0004] Existing impregnation molds are divided into encapsulated type and curved type impregnation molds according to their structures. Encapsulated type impregnation molds fill the entire internal cavity of the mold with molten resin through the injection port, which makes it impossible to form a closed space and establish effective impregnation pressure. In addition, the molten resin may be carbonized and the resin performance may deteriorate if it is exposed to high temperature for a long time. Curved type impregnation molds build pressure through the wedge-shaped area formed by the prepreg tape and the tooth tip in the mold. This type of mold has a small space inside, which is difficult to clean later. When the tooth tip contacts the fiber bundle, it is very easy to damage the fiber, affecting the performance of the final product.

[0005] In view of the above problems, it is urgent to propose a preparation equipment and process method for continuous fiber reinforced thermoplastic composite prepreg tape (material) with high production efficiency, low cost, simple operation and high impregnation quality without damaging the fibers. Summary of the invention

[0006] In view of this, the present invention aims to propose a melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg tapes, so as to solve the problems of high porosity, low impregnation degree and easy fiber breakage during the preparation process faced by the current fiber reinforced high-viscosity thermoplastic resin prepreg tapes.

[0007] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0008] A melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg tapes, comprising a top cover assembly and a dipping bottom tank assembly, wherein the top cover assembly comprises an upper cover plate, an adjustable-height dipping roller and an upper calender roller, and a plurality of adjustable-height dipping rollers are evenly arranged on the lower surface of the upper cover plate, and the dipping bottom tank assembly comprises a U-shaped bottom plate, a fixed-height dipping roller and a lower calender roller, a plurality of fixed-height dipping rollers are evenly arranged on the U-shaped bottom plate, and a plurality of heating rods are evenly penetrated inside the upper cover plate and the U-shaped bottom plate;

[0009] When the upper cover plate and the U-shaped bottom plate are buckled together, an impregnation mold is formed. The front end of the impregnation mold is the mold outlet end, and the rear end is the mold inlet end. The upper calender roller is arranged on the upper cover plate near the mold outlet end, and the lower calender roller is arranged on the U-shaped bottom plate near the mold outlet end.

[0010] When the upper cover plate is buckled with the U-shaped bottom plate, several adjustable height impregnation rollers on the upper cover plate and several fixed rod height impregnation rollers on the U-shaped bottom plate are arranged alternately, the upper calendering roller and the lower calendering roller are arranged vertically opposite each other, and the height of the adjustable height impregnation roller from the U-shaped bottom plate gradually decreases from the mold inlet end to the mold outlet end, so that the impregnation pressure on the resin melt arranged from the mold inlet end to the mold outlet end and the covering angle formed by the impregnation roller and the fiber bundle will gradually increase.

[0011] Furthermore, the adjustable height impregnation roller includes an adjustable support and a first round roller. The adjustable support is a U-shaped structure. Open long grooves are provided on both side surfaces of the adjustable support of the U-shaped structure. A threaded column is connected to each end of the first round roller. The first round roller is arranged in the U-shaped structure. Two threaded columns are set through the open long grooves on the corresponding sides and are each positioned with a hexagonal nut.

[0012] Furthermore, the fixed-height impregnation roller includes a fixed support and a second round roller, the second round roller is fixed on the upper surface of the fixed support, and the fixed support is fixed on the bottom surface of the U-shaped bottom plate.

[0013] Furthermore, a plurality of grooves for accommodating the adjustable supports are provided on the inner walls on both sides of the U-shaped bottom plate.

[0014] Furthermore, the adjustable height impregnation roller and the upper calendering roller are fixedly connected to the upper cover plate via a plurality of fixing bolts, and the fixed height impregnation roller and the lower calendering roller are also fixedly connected to the bottom surface of the U-shaped bottom plate via a plurality of fixing bolts.

[0015] Furthermore, the thermoplastic resin matrix of the thermoplastic fiber reinforced resin-based prepreg tape is polyetheretherketone, nylon 6 or polypropylene; and the reinforcing fibers are continuous carbon fibers or continuous glass fibers.

[0016] Furthermore, the length of the upper cover plate is not less than 800 mm, the number of adjustable height dipping rollers is not less than 5, the height of each adjustable height dipping roller is adjustable in the range of 22 mm to 55 mm, the diameters of the first round roller and the second round roller are the same and not less than 16 mm, and the length is consistent with the width of the prepared strip; the height of the U-shaped bottom plate is not less than 65 mm.

[0017] Furthermore, the upper calendering roller and the lower calendering roller form a thin gap with a thickness less than 0.3 mm at the outlet end of the mold.

[0018] Furthermore, the heating rods in the upper cover plate are evenly arranged along the length direction of the upper cover plate, and the heating rods in the U-shaped bottom plate are evenly arranged along the length direction of the U-shaped bottom plate, and the number is not less than 9, and the distance between adjacent heating rods is not more than 100mm.

[0019] Another object of the present invention is to provide a method for preparing a continuous fiber reinforced high viscosity thermoplastic resin prepreg by melt impregnation of a mold to prepare a prepreg, which specifically comprises the following steps:

[0020] Step 1) adjusting the height of the adjustable height impregnation roller: first loosen the hexagonal nut on the adjustable height impregnation roller, and adjust the height of the first round roller of the plurality of adjustable height impregnation rollers from the bottom of the adjustable base, so that the height of the first round roller from the mold inlet end to the mold outlet end from the bottom of the adjustable base gradually increases, thereby forming a trend of gradually increasing impregnation pressure and coating angle;

[0021] Step 2) preheating: buckle the top cover assembly and the dipping bottom tank assembly, and gradually increase the temperature through the heating rods of the upper cover plate and the U-shaped bottom plate to a temperature higher than the melting temperature of the thermoplastic resin;

[0022] Step 3) Mold penetration: lift the top cover assembly, pull the continuous fiber bundle with yarn spread and glue coated on the upper surface from the mold inlet end into the mold, and pass through the adjustable height impregnation roller with gradually increasing height to gradually deepen the impregnation of the fiber bundle with the resin melt to finally achieve complete impregnation, while reducing the impregnation pressure at the inlet end where the fiber is most vulnerable to damage to protect the fiber from damage;

[0023] Step 4) Calendering: The fully impregnated fiber bundle passes through the upper calendering roller and the lower calendering roller from the die outlet to scrape off the excess resin and calender the surface of the prepreg tape before being pulled out. After cooling, it becomes a continuous fiber reinforced thermoplastic resin prepreg tape.

[0024] Compared with the prior art, the beneficial effects of the present invention on the preparation of a continuous fiber reinforced high-viscosity thermoplastic resin prepreg melt impregnation mold are as follows:

[0025] (1) The present invention creates a melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg tape, which can adjust the impregnation pressure and the wrapping angle in the impregnation mold, and different impregnation pressures and wrapping angles can be applied at different positions in the mold. A corresponding process method is developed, that is, the height of the impregnation roller on the cover plate is gradually increased from the mold inlet end to the mold outlet end so that the impregnation pressure and the wrapping angle are gradually increased; the reason for this setting is that as the impregnation depth increases, the required impregnation pressure also gradually increases, so the use of this impregnation mold can effectively solve the problem of difficulty in impregnating high-viscosity resins.

[0026] (2) The present invention creates a melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg tape, which can protect the fibers from damage during the preparation process. Since the fibers and resin have not yet combined at the inlet end of the impregnation mold, the fiber filaments are easily damaged under the action of the impregnation pressure during the contact between the fiber bundle and the impregnation roller. This patent protects the fiber filaments from damage by lowering the height of the impregnation roller at the inlet end of the mold to reduce the impregnation pressure. As the fibers and resin gradually combine, the fiber filaments are no longer easy to break. The height of the impregnation roller can be gradually increased to increase the impregnation pressure to improve the impregnation quality. Therefore, the use of this impregnation mold can effectively solve the problem of easy damage to the fibers during the preparation process.

[0027] (3) The present invention creates a melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg, which can achieve the preparation of thermoplastic resin prepreg with high fiber content and high surface finish. A calendering roller is arranged at the outlet end of the mold. The surface of the calendering roller is chrome-plated to ensure smoothness, and the upper and lower calendering rollers form a narrow gap with a thickness of less than 0.3 mm to scrape off excess resin and calender the surface when the prepreg is about to be pulled out of the impregnation mold. Therefore, the use of this impregnation mold can effectively solve the problems of rough surface and low fiber content of the prepreg during the preparation process.

[0028] (4) The present invention creates a melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg tape, which has a simple design, low cost, convenient processing of various components, high preparation continuity and high production efficiency, and is simple to operate and has strong applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings constituting part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0030] Figure 1 A schematic structural diagram of a mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg melt impregnation mold according to an embodiment of the present invention;

[0031] Figure 2 This is an axonometric view of a top cover of a mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg melt impregnation mold according to an embodiment of the present invention;

[0032] Figure 3 This is a front view of a top cover of a mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg melt impregnation mold according to an embodiment of the present invention;

[0033] Figure 4 A top view of a top cover of a mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg melt impregnation mold according to an embodiment of the present invention;

[0034] Figure 5 A side view of a top cover of a mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg melt-impregnated tape according to an embodiment of the present invention;

[0035] Figure 6 This is an axonometric view of a bottom tank of a mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg melt impregnation mold according to an embodiment of the present invention;

[0036] Figure 7 This is a front view of a dipping bottom tank of a mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg melt-impregnation mold according to an embodiment of the present invention;

[0037] Figure 8 A top view of a bottom tank of a mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg melt-impregnated tape according to an embodiment of the present invention;

[0038] Fig. 9 A side view of a bottom tank of a mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg melt impregnation mold according to an embodiment of the present invention;

[0039] Fig.10 This is an axonometric view of an adjustable height impregnation roller in a melt impregnation mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg according to an embodiment of the present invention;

[0040] Fig.11A front view of an adjustable height impregnation roller in a melt impregnation mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg according to an embodiment of the present invention;

[0041] Fig.12 A top view of an adjustable height impregnation roller in a melt impregnation mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg according to an embodiment of the present invention;

[0042] Fig.13 A side view of an adjustable height impregnation roller in a melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg tapes described in an embodiment of the present invention.

[0043] Description of reference numerals:

[0044] 1. Top cover assembly; 2. Glue dipping bottom tank assembly; 3. Upper cover plate; 4. Adjustable height dipping roller; 5. U-shaped bottom plate; 6. Fixed height dipping roller; 7. Fixing bolts; 8. Upper calendering roller; 9. Lower calendering roller; 10. Mold inlet end; 11. Mold outlet end; 12. Heating rod; 401. Adjustable support; 4011. Open long groove; 402. First round roller; 4021. Threaded column; 501. Groove; 601. Fixed support; 602. Second round roller. DETAILED DESCRIPTION

[0045] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0047] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0048] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0049] like Figure 1-Figure 13 As shown, a melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg tapes comprises a top cover assembly 1 and a dipping bottom tank assembly 2, wherein the top cover assembly 1 comprises an upper cover plate 3, an adjustable height dipping roller 4 and an upper calendering roller 8, and a plurality of adjustable height dipping rollers 4 are evenly arranged on the lower surface of the upper cover plate 3, and the dipping bottom tank assembly 2 comprises a U-shaped bottom plate 5, a fixed height dipping roller 6 and a lower calendering roller 9, and a plurality of fixed height dipping rollers 6 are evenly arranged on the U-shaped bottom plate 5, and a plurality of heating rods 12 are evenly penetrated inside the upper cover plate 3 and the U-shaped bottom plate 5;

[0050] The upper cover plate 3 and the U-shaped bottom plate 5 are buckled to form an impregnation mold, the front end of the impregnation mold is the mold outlet end 11, the rear end is the mold inlet end 10, the upper calender roller 8 is arranged on the upper cover plate 2 near the mold outlet end, and the lower calender roller 9 is arranged on the U-shaped bottom plate 5 near the mold outlet end;

[0051] When the upper cover plate 3 is buckled with the U-shaped bottom plate 5, a plurality of adjustable height impregnation rollers 4 on the upper cover plate 3 and a plurality of fixed rod height impregnation rollers 6 on the U-shaped bottom plate 5 are arranged alternately, an upper calendering roller 8 and a lower calendering roller 9 are arranged vertically opposite each other, and a height of the adjustable height impregnation roller 4 from the U-shaped bottom plate gradually decreases from the mold inlet end 10 to the mold outlet end 11, so that the impregnation pressure on the resin melt arranged from the mold inlet end 10 to the mold outlet end 11 and the covering angle formed by the impregnation roller and the fiber bundle will gradually increase.

[0052] The adjustable height impregnation roller comprises an adjustable support 401 and a first round roller 402. The adjustable support 401 is a U-shaped structure. An open long groove 4011 is provided on both sides of the adjustable support of the U-shaped structure. A threaded column 4021 is connected to each end of the first round roller 402. The length is not more than 6 mm and the diameter is slightly smaller than the width of the open long groove 4011 on the adjustable fixed support 401. The first round roller 402 is arranged in the U-shaped structure. Two threaded columns 4021 are arranged through the open long grooves on the corresponding sides and each is positioned with a hexagonal nut. The first round roller 402 can be fixed to the adjustable support 401 by passing the threaded column 4021 through the open long groove 4011 and tightening it with a hexagonal nut. The position of the first round roller 402 can be adjusted up and down by loosening the hexagonal nut, thereby realizing the height adjustment of the adjustable height impregnation roller 4.

[0053] The fixed height dipping roller 6 includes a fixed support 601 and a second round roller 602, wherein the second round roller 602 is fixed on the upper surface of the fixed support 601, and the fixed support 601 is fixed on the bottom surface of the U-shaped bottom plate 5. There are no less than 5 fixed height dipping rollers 6; the height of the dipping bottom tank assembly 2 is no less than 65 mm; a plurality of groups of grooves 501 for accommodating the adjustable support 401 are provided on the inner walls on both sides of the U-shaped bottom plate 5; the position of the groove 501 is consistent with the position of the adjustable dipping roller 4 to accommodate the adjustable support 401 of the adjustable dipping roller 4.

[0054] The adjustable height impregnation roller 4 and the upper calender roller 8 are fixedly connected to the upper cover plate 3 via a plurality of fixing bolts 7 , and the fixed height impregnation roller 6 and the lower calender roller 9 are also fixedly connected to the bottom surface of the U-shaped bottom plate 5 via a plurality of fixing bolts.

[0055] The thermoplastic resin matrix of the thermoplastic fiber reinforced resin-based prepreg tape is polyetheretherketone (PEEK), nylon 6 (PA6) or polypropylene (PP); the reinforcing fibers are continuous carbon fibers or continuous glass fibers.

[0056] The length of the upper cover plate 3 is not less than 800 mm, the number of adjustable height dipping rollers 4 is not less than 5, the height of each adjustable height dipping roller 4 is adjustable in the range of 22 mm-55 mm, the diameters of the first round roller 402 and the second round roller 602 are the same and not less than 16 mm, the length is consistent with the width of the prepared strip, the surface chrome plating thickness is 0.1-0.15 mm, and the surface roughness is less than 0.014 μm; the height of the U-shaped bottom plate 5 is not less than 65 mm.

[0057] The upper calender roller 8 and the lower calender roller 9 form a thin gap with a thickness less than 0.3 mm at the die outlet end 11, the surface chrome plating thickness is greater than 0.1 mm, and the surface roughness is less than 0.012 μm.

[0058] The heating rods in the upper cover plate 3 are evenly arranged along the length direction of the upper cover plate 3, and the heating rods in the U-shaped bottom plate 5 are evenly arranged along the length direction of the U-shaped bottom plate 5, and the number is not less than 9, and the distance between adjacent heating rods is not more than 100mm.

[0059] The product prepared by the present invention has low porosity, good impregnation degree and no fiber damage, and the impregnation pressure and coating angle are adjustable during the application of the impregnation mold, which can effectively solve the problems of difficult impregnation and easy fiber damage in the preparation of high-viscosity resin (such as PEEK resin) based composite material prepregs.

[0060] Another object of the present invention is to provide a method for preparing a continuous fiber reinforced high viscosity thermoplastic resin prepreg by melt impregnation of a mold to prepare a prepreg, which specifically comprises the following steps:

[0061] Step 1) adjusting the height of the adjustable height impregnation roller 4: first loosen the hexagonal nut on the adjustable height impregnation roller 4, and adjust the height of the first round roller 402 of the plurality of adjustable height impregnation rollers 4 from the bottom of the adjustable base, so that the height of the first round roller 402 from the bottom of the adjustable base in the direction from the mold inlet end 10 to the mold outlet end 11 gradually increases, thereby forming a trend of gradually increasing impregnation pressure and coating angle;

[0062] Step 2) preheating: buckle the top cover assembly 1 and the dipping bottom tank assembly 2, and gradually increase the temperature through the heating rod 12 of the upper cover plate 3 and the U-shaped bottom plate 5 to a temperature higher than the melting temperature of the thermoplastic resin;

[0063] Step 3) Mold penetration: lift the top cover 1, pull the continuous fiber bundle with yarn spread and glue coated on the upper surface into the mold from the mold inlet end 10, and pass through the adjustable height impregnation roller 4 with gradually increasing height to gradually deepen the impregnation of the fiber bundle with the resin melt to finally achieve complete impregnation, and at the same time reduce the impregnation pressure at the inlet end where the fiber is most vulnerable to damage to protect the fiber from damage;

[0064] Step 4) Calendering: The fully impregnated fiber bundle passes through the upper calendering roller 8 and the lower calendering roller 9 from the mold outlet end 11 to scrape off the excess resin and calender the surface of the prepreg tape, and then is pulled out, and after cooling, it becomes a continuous fiber reinforced thermoplastic resin prepreg tape.

[0065] Here are some specific examples:

[0066] Specific example 1: Preparation of continuous carbon fiber reinforced polyetheretherketone (PEEK) prepreg tape (material)

[0067] A mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg tape (material) melt impregnation mold includes a top cover component 1 and a dipping bottom tank component 2, wherein the top cover component 1 includes an upper cover plate 3, an adjustable height dipping roller 4 and an upper calendering roller 8, and a plurality of adjustable height dipping rollers 4 are evenly arranged on the lower surface of the upper cover plate 3, and the dipping bottom tank component 2 includes a U-shaped bottom plate 5, a fixed height dipping roller 6 and a lower calendering roller 9, and a plurality of fixed height dipping rollers 6 are evenly arranged on the U-shaped bottom plate 5, and a plurality of fixed height dipping rollers 6 are evenly arranged on the upper cover plate 3 and the U-shaped A plurality of heating rods 12 are evenly arranged inside the bottom plate 5; the adjustable height impregnation roller comprises an adjustable support 401 and a first round roller 402, the adjustable support 401 is a U-shaped structure, and an open long groove 4011 is provided on both sides of the adjustable support of the U-shaped structure, and a threaded column 4021 is connected to each end of the first round roller 402, and the first round roller 402 is arranged in the U-shaped structure, and two threaded columns 4021 are arranged through the open long grooves on the corresponding sides, and each is positioned with a hexagonal nut;

[0068] The fixed height impregnation roller 6 comprises a fixed support 601 and a second round roller 602, wherein the second round roller 602 is fixed on the upper surface of the fixed support 601, and the fixed support 601 is fixed on the bottom surface of the U-shaped bottom plate 5;

[0069] The adjustable height impregnation roller 4 and the upper calender roller 8 are fixedly connected to the upper cover plate 3 through a plurality of fixing bolts 7, and the fixed height impregnation roller 6 and the lower calender roller 9 are also fixedly connected to the bottom surface of the U-shaped bottom plate 5 through a plurality of fixing bolts;

[0070] The upper cover plate 3 and the U-shaped bottom plate 5 are buckled to form an impregnation mold, the front end of the impregnation mold is the mold outlet end 11, the rear end is the mold inlet end 10, the upper calender roller 8 is arranged on the upper cover plate 2 near the mold outlet end, and the lower calender roller 9 is arranged on the U-shaped bottom plate 5 near the mold outlet end;

[0071] When the upper cover plate 3 is buckled with the U-shaped bottom plate 5, a plurality of adjustable height impregnation rollers 4 on the upper cover plate 3 and a plurality of fixed rod height impregnation rollers 6 on the U-shaped bottom plate 5 are arranged alternately, and the upper calendering roller 8 and the lower calendering roller 9 are arranged vertically opposite to each other. The height of the adjustable height impregnation roller 4 from the U-shaped bottom plate gradually decreases from the mold inlet end 10 to the mold outlet end 11. A wavy and gradually increasing connecting line is formed through the adjustable height impregnation roller 4 on the upper cover plate 3 and the fixed height impregnation roller 6 on the U-shaped bottom plate 5, so that the impregnation pressure on the resin melt arranged from the mold inlet end 10 to the mold outlet end 11 and the covering angle formed by the impregnation roller and the fiber bundle will gradually increase.

[0072] The length of the upper cover plate 3 is 800 mm; the number of the adjustable height dipping rollers 4 is 5, and the heights of the 5 adjustable height dipping rollers 4 are adjusted to 25 mm, 30 mm, 40 mm, 50 mm, and 55 mm from the mold inlet end 10 to the mold outlet end 11 in sequence.

[0073] The first round roller 402 and the second round roller 602 have the same diameter of 20 mm, the length is consistent with the width of the prepared strip (material), and the surface chrome plating thickness is 0.1 mm; the first round roller 402 has a threaded column 4021 with a length of 6 mm protruding outward from the axis on both sides of the circular section, and the diameter is slightly smaller than the width of the open long slot 4011 on the adjustable support 401. The threaded column 4021 passes through the open long slot 4011 and is tightened with a hexagonal nut to fix the round roller 402 on the adjustable support 401. The position of the first round roller 402 can be adjusted up and down by loosening the hexagonal nut, thereby realizing the height adjustment of the adjustable height impregnation roller 4.

[0074] The height of the dipping tank assembly 2 is 65 mm. Grooves 501 are provided on the inner walls of both sides of the U-shaped bottom plate 5. The position of the grooves 501 is consistent with the position of the adjustable dipping roller 4 to accommodate the fixed support 401 of the adjustable dipping roller 4. The number of fixed height dipping rollers is 5.

[0075] The upper calender roller 8 and the lower calender roller 9 are arranged vertically opposite to each other, and a 0.3mm-thick slit is formed between the two at the die outlet 11, and the surface chrome plating thickness is 0.12mm. The heating rods 12 are arranged along the length direction of the upper cover plate 3 and the U-shaped bottom plate 5, respectively. The upper cover plate 3 is provided with 11 heating rods, and the U-shaped bottom plate 5 is provided with 10 heating rods, and the distance between adjacent heating rods is 75mm.

[0076] The preparation method of the above device comprises the following steps:

[0077] Step 1) adjusting the height of the adjustable height impregnation roller 4: first loosen the hexagonal nut on the adjustable height impregnation roller 4, adjust the height of the adjustable height impregnation roller 4, and adjust the heights of the five adjustable height impregnation rollers 4 from the mold inlet end 10 to the mold outlet end 11 to 25 mm, 30 mm, 40 mm, 50 mm, and 55 mm in sequence, so that the impregnation pressure and the coating angle formed from the mold inlet end 10 to the outlet end 11 are gradually increased;

[0078] Step 2) preheating: buckle the top cover assembly 1 and the dipping bottom tank assembly 2, and gradually increase the temperature of the heating rods 12 of the upper cover plate 3 and the U-shaped bottom plate 5 through the control circuit to be higher than the melting temperature of the PEEK resin; adjust the temperature of the heating rods of the top cover assembly 1 and the dipping bottom tank assembly 2 to 420°C; before starting the preparation, control the internal temperature of the impregnation mold between 400°C and 420°C and keep it constant to ensure that the resin is in a flowing state after entering the mold and can immediately impregnate the fiber under the driving action of the impregnation pressure;

[0079] Step 3) passing through the mold: lifting the top cover assembly 1, pulling a certain number of continuous carbon fiber bundles from the mold inlet end 10 into the mold, passing through the bottom of the adjustable height impregnation roller 4 and the top of the fixed height impregnation roller in turn, and then passing through the outlet end 11 and fixed at the traction device;

[0080] Step 4) Closing the mold: lower the top cover assembly 1 so that it fits with the resin-impregnated bottom tank assembly 2 to form a sealed whole. At this time, the continuous carbon fiber bundles will form a wave-shaped gradually increasing connection line;

[0081] Step 5) Preparation starts: Turn on the extruder control switch, extrude the resin and apply it flat on the upper surface of the fiber bundle and turn on the traction device. The coated fiber bundle passes through the adjustable height impregnation roller 4 with gradually increasing height to gradually deepen the impregnation of the fiber bundle with the resin melt and finally achieve complete impregnation. At the same time, since the impregnation pressure at the mold inlet end 10 is relatively small, the carbon fiber is protected from damage;

[0082] Step 6) Calendering at the outlet: The fully impregnated fiber bundle passes through the upper calendering roller 8 and the lower calendering roller 9 from the mold outlet 11 to scrape off the excess resin and calender the surface of the prepreg tape, and then it is led out by the traction device. After cooling, it becomes a continuous carbon fiber reinforced PEEK resin prepreg tape (material).

[0083] Specific Example 2: Preparation of Continuous Glass Fiber Reinforced Polypropylene (PP) Prepreg Tape (Material)

[0084] A mold for preparing a continuous fiber reinforced high-viscosity thermoplastic resin prepreg tape (material) melt impregnation mold includes a top cover component 1 and a dipping bottom tank component 2, wherein the top cover component 1 includes an upper cover plate 3, an adjustable height dipping roller 4 and an upper calendering roller 8, and a plurality of adjustable height dipping rollers 4 are evenly arranged on the lower surface of the upper cover plate 3, and the dipping bottom tank component 2 includes a U-shaped bottom plate 5, a fixed height dipping roller 6 and a lower calendering roller 9, and a plurality of fixed height dipping rollers 6 are evenly arranged on the U-shaped bottom plate 5, and a plurality of fixed height dipping rollers 6 are evenly arranged on the upper cover plate 3 and the U A plurality of heating rods 12 are evenly arranged inside the bottom plate 5; the height-adjustable impregnation roller comprises an adjustable support 401 and a first round roller 402, the adjustable support 401 is a U-shaped structure, and both sides of the adjustable support of the U-shaped structure are provided with open long grooves 4011, and a threaded column 4021 is connected to each of the two ends of the first round roller 402, the first round roller 402 is arranged in the U-shaped structure, and two threaded columns 4021 are arranged through the open long grooves on the corresponding sides, and each is positioned with a hexagonal nut;

[0085] The fixed height impregnation roller 6 comprises a fixed support 601 and a second round roller 602, wherein the second round roller 602 is fixed on the upper surface of the fixed support 601, and the fixed support 601 is fixed on the bottom surface of the U-shaped bottom plate 5;

[0086] The adjustable height impregnation roller 4 and the upper calender roller 8 are fixedly connected to the upper cover plate 3 through a plurality of fixing bolts 7, and the fixed height impregnation roller 6 and the lower calender roller 9 are also fixedly connected to the bottom surface of the U-shaped bottom plate 5 through a plurality of fixing bolts;

[0087] The upper cover plate 3 and the U-shaped bottom plate 5 are buckled to form an impregnation mold, the front end of the impregnation mold is the mold outlet end 11, the rear end is the mold inlet end 10, the upper calender roller 8 is arranged on the upper cover plate 2 near the mold outlet end, and the lower calender roller 9 is arranged on the U-shaped bottom plate 5 near the mold outlet end;

[0088] When the upper cover plate 3 is buckled with the U-shaped bottom plate 5, the plurality of adjustable height impregnation rollers 4 on the upper cover plate 3 and the plurality of fixed rod height impregnation rollers 6 on the U-shaped bottom plate 5 are arranged alternately, the upper calender roller 8 and the lower calender roller 9 are arranged vertically opposite to each other, the height of the adjustable height impregnation roller 4 from the U-shaped bottom plate gradually decreases from the mold inlet end 10 to the mold outlet end 11, and a wave-shaped gradually increasing connecting line is formed through the adjustable height impregnation roller 4 on the upper cover plate 3 and the fixed height impregnation roller 6 on the U-shaped bottom plate 5, so that the impregnation pressure on the resin melt arranged from the mold inlet end 10 to the mold outlet end 11 and the covering angle formed by the impregnation roller and the fiber bundle will gradually increase;

[0089] The length of the upper cover plate 3 is 800 mm; the number of the adjustable height dipping rollers 4 is 5, and the heights of the 5 adjustable height dipping rollers 4 are adjusted to 25 mm, 30 mm, 35 mm, 40 mm, and 45 mm from the mold inlet end 10 to the mold outlet end 11 in sequence.

[0090] The first round rollers 402 and 602 have the same diameter of 20 mm, and the length is consistent with the width of the prepared strip (material), and the surface chrome plating thickness is 0.1 mm; the circular cross-sections on both sides of the first round roller 402 protrude outward from the axis with a threaded column 4021 with a length of 6 mm, and the diameter is slightly smaller than the width of the open long groove 4011 on the adjustable support 401; the threaded column 4021 is passed through the open long groove 4011 and tightened with a hexagonal nut to fix the first round roller 402 on the adjustable support 401, and the position of the first round roller 402 can be adjusted up and down by loosening the hexagonal nut, thereby realizing the height adjustment of the adjustable height impregnation roller 4.

[0091] The height of the dipping tank assembly 2 is 65 mm. Grooves 501 are provided on the inner walls of both sides of the U-shaped bottom plate 5. The position of the grooves 501 is consistent with the position of the adjustable dipping roller 4 to accommodate the fixed support 401 of the adjustable dipping roller 4. The number of fixed height dipping rollers is 5.

[0092] The upper calender roller 8 and the lower calender roller 9 are arranged vertically opposite to each other, and a 0.3mm-thick slit is formed between the two at the die outlet 11, and the surface chrome plating thickness is 0.12mm. The heating rods 12 are arranged along the length direction of the upper cover plate 3 and the U-shaped bottom plate 5, respectively. The upper cover plate 3 is provided with 11 heating rods, and the U-shaped bottom plate 5 is provided with 10 heating rods, and the distance between adjacent heating rods is 75mm.

[0093] The preparation method of the above device comprises the following steps:

[0094] Step 1) adjusting the height of the adjustable height impregnation roller 4: first loosen the hexagonal nut on the adjustable height impregnation roller 4, adjust the height of the adjustable height impregnation roller 4, and adjust the height of the five adjustable height impregnation rollers 4 from the mold inlet end 10 to the mold outlet end 11 to 25 mm, 30 mm, 35 mm, 40 mm, and 45 mm in sequence, so that the impregnation pressure and the coating angle formed from the mold inlet end 10 to the mold outlet end 11 are gradually increased;

[0095] Step 2) preheating: buckle the top cover assembly 1 and the dipping bottom tank assembly 2, and gradually increase the temperature of the heating rods 12 of the upper cover plate 3 and the U-shaped bottom plate 5 through the control circuit to be higher than the melting temperature of the PP resin; adjust the temperature of the heating rods of the top cover assembly 1 and the dipping bottom tank assembly 2 to 270°C; before starting the preparation, control the internal temperature of the impregnation mold between 250°C and 270°C and keep it constant to ensure that the resin is in a flowing state after entering the mold and can immediately impregnate the fiber under the driving action of the impregnation pressure;

[0096] Step 3) passing through the mold: lifting the top cover assembly 1, pulling a certain number of continuous glass fiber bundles from the mold inlet end 10 into the mold, passing through the bottom of the adjustable height impregnation roller 4 and the top of the fixed height impregnation roller in turn, and then passing through the mold outlet end 11, and fixed at the pulling device;

[0097] Step 4) Closing the mold: lower the top cover assembly 1 so that it fits with the dipped bottom tank assembly 2 to form a sealed whole. At this time, the continuous glass fibers will form a wave-shaped gradually increasing connection line;

[0098] Step 5) Preparation starts: Turn on the extruder control switch, extrude the resin and apply it flat on the upper surface of the fiber bundle and turn on the traction device. The coated fiber bundle passes through the adjustable height impregnation roller 4 with gradually increasing height to gradually deepen the impregnation of the fiber bundle with the resin melt and finally achieve complete impregnation. At the same time, since the impregnation pressure at the mold inlet end 10 is relatively small, the carbon fiber is protected from damage;

[0099] Step 6) Calendering at the outlet: The fully impregnated fiber bundle passes through the upper calendering roller 8 and the lower calendering roller 9 from the mold outlet 11 to scrape off the excess resin and calender the surface of the prepreg tape, and then it is led out by the traction device. After cooling, it becomes a continuous glass fiber reinforced PP resin prepreg tape (material).

[0100] The embodiments of the invention disclosed above are only used to help illustrate the invention. The embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. According to the content of this specification, many modifications and changes can be made. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the invention, so that those skilled in the art can understand and use the invention well.

Claims

1. A melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg, characterized in that: The invention comprises a top cover assembly (1) and a dipping tank assembly (2), wherein the top cover assembly (1) comprises an upper cover plate (3), an adjustable-height dipping roller (4) and an upper calendering roller (8), wherein a plurality of adjustable-height dipping rollers (4) are evenly arranged on the lower surface of the upper cover plate (3), and the dipping tank assembly (2) comprises a U-shaped bottom plate (5), a fixed-height dipping roller (6) and a lower calendering roller (9), wherein a plurality of fixed-height dipping rollers (6) are evenly arranged on the U-shaped bottom plate (5), and a plurality of heating rods (12) are evenly penetrated inside the upper cover plate (3) and the U-shaped bottom plate (5); When the upper cover plate (3) and the U-shaped bottom plate (5) are buckled together, an impregnation mold is formed. The front end of the impregnation mold is the mold outlet end (11), and the rear end is the mold inlet end (10). The upper calendering roller (8) is arranged on the upper cover plate (2) near the mold outlet end, and the lower calendering roller (9) is arranged on the U-shaped bottom plate (5) near the mold outlet end. When the upper cover plate (3) is buckled with the U-shaped bottom plate (5), a plurality of adjustable-height impregnation rollers (4) on the upper cover plate (3) and a plurality of fixed-height impregnation rollers (6) on the U-shaped bottom plate (5) are arranged alternately, an upper calender roller (8) and a lower calender roller (9) are arranged vertically opposite each other, and the height of the adjustable-height impregnation roller (4) from the U-shaped bottom plate gradually decreases from the mold inlet end (10) to the mold outlet end (11), so that the impregnation pressure on the resin melt arranged from the mold inlet end (10) to the mold outlet end (11) and the wrapping angle formed by the impregnation roller and the fiber bundle are gradually increased; The adjustable height impregnation roller comprises an adjustable support (401) and a first round roller (402); the adjustable support (401) is a U-shaped structure; both side surfaces of the adjustable support of the U-shaped structure are provided with open long grooves (4011); a threaded column (4021) is connected to each of the two ends of the first round roller (402); the first round roller (402) is arranged in the U-shaped structure; two threaded columns (4021) are arranged through the open long grooves on the corresponding sides and are each positioned with a hexagonal nut.

2. The melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg according to claim 1, characterized in that: The fixed-height impregnation roller (6) comprises a fixed support (601) and a second round roller (602), wherein the second round roller (602) is fixed on the upper surface of the fixed support (601), and the fixed support (601) is fixed on the bottom surface of the U-shaped bottom plate (5).

3. The melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg according to claim 1, characterized in that: A plurality of groups of grooves (501) for accommodating the adjustable supports (401) are provided on the inner walls on both sides of the U-shaped bottom plate (5).

4. The melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg according to claim 1, characterized in that: The adjustable height impregnation roller (4) and the upper calendering roller (8) are fixedly connected to the upper cover plate (3) via a plurality of fixing bolts (7), and the fixed height impregnation roller (6) and the lower calendering roller (9) are also fixedly connected to the bottom surface of the U-shaped bottom plate (5) via a plurality of fixing bolts.

5. The melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg according to claim 1, characterized in that: The thermoplastic resin matrix of the continuous fiber reinforced high-viscosity thermoplastic resin prepreg tape is polyetheretherketone, nylon 6 or polypropylene; the reinforcing fiber is continuous carbon fiber or continuous glass fiber.

6. The melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg according to claim 2, characterized in that: The length of the upper cover plate (3) is not less than 800 mm, the number of the height-adjustable dipping rollers (4) is not less than 5, the height of each height-adjustable dipping roller (4) is adjustable within a range of 22 mm to 55 mm, the diameters of the first round roller (402) and the second round roller (602) are the same and not less than 16 mm, and the length is consistent with the width of the prepared strip; the height of the U-shaped bottom plate (5) is not less than 65 mm.

7. The melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg according to claim 1, characterized in that: The upper calender roller (8) and the lower calender roller (9) form a thin gap with a thickness of less than 0.3 mm at the die outlet end (11).

8. The melt impregnation mold for preparing continuous fiber reinforced high-viscosity thermoplastic resin prepreg according to claim 1, characterized in that: The heating rods in the upper cover plate (3) are evenly arranged along the length direction of the upper cover plate (3), and the heating rods in the U-shaped bottom plate (5) are evenly arranged along the length direction of the U-shaped bottom plate (5), and the number of the heating rods is not less than 9, and the distance between adjacent heating rods is not greater than 100 mm.

9. A method for preparing a continuous fiber reinforced high viscosity thermoplastic resin prepreg by melt impregnation of a mold to prepare a prepreg according to any one of claims 1 to 8, characterized in that: The specific steps include: Step 1) adjusting the height of the adjustable height impregnation roller (4): first loosen the hexagonal nut on the adjustable height impregnation roller (4), and adjust the height of the first round roller (402) of the plurality of adjustable height impregnation rollers (4) from the top of the adjustable support, so that the height of the first round roller (402) from the top of the adjustable support in the direction from the mold inlet end (10) to the mold outlet end (11) gradually increases, thereby forming a trend of gradually increasing the impregnation pressure and the coating angle; Step 2) preheating: buckle the top cover assembly (1) and the dipping bottom tank assembly (2), and gradually increase the temperature through the heating rods (12) of the upper cover plate (3) and the U-shaped bottom plate (5) to a temperature higher than the melting temperature of the thermoplastic resin; Step 3) passing through the mold: lifting the top cover assembly (1), pulling the continuous fiber bundle with the yarn spread and the upper surface coated with glue into the mold from the mold inlet end (10), passing through the gradually increasing height adjustable impregnation roller (4) to gradually deepen the impregnation of the fiber bundle with the resin melt and finally achieve complete impregnation, while reducing the impregnation pressure at the inlet end where the fiber is most vulnerable to damage to protect the fiber from damage; Step 4) Calendering: The fully impregnated fiber bundle passes through the upper calendering roller (8) and the lower calendering roller (9) from the mold outlet end (11) to scrape off excess resin and calender the surface of the prepreg tape, and then pull it out. After cooling, it becomes a continuous fiber reinforced thermoplastic resin prepreg tape.

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