A multi-layer fiber prepreg and its preparation method and production device
By adding N-layer reinforcement material and resin film to the surface of the single-layer fiber prepreg produced continuously online, and performing impregnation treatment, the problem of poor wettability of the large gram-weight fiber prepreg resin is solved, and a multi-layer fiber prepreg production with high impregnation and stable performance is achieved.
Patent Information
- Application Number
- CN202510197838.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-21
- Publication Date
- 2025-04-04
AI Technical Summary
The resin wetting properties of existing large gram heavy fiber prepregs lead to dry yarn of reinforcement material, resulting in layering of parts and local bubble defects, affecting performance.
N-layer reinforcement material is added to the surface of the single-layer fiber prepreg produced continuously online, and a layer of resin film is added for each additional layer, and the impregnation treatment is carried out to control the temperature and pressure to prepare multi-layer fiber prepreg.
The production of fiber prepregs with a high degree of impregnation is achieved, which improves the stability and mechanical properties of the prepregs, solves the problem of low impregnation and reduces the consumption of human resources.
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Figure CN119748694A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of carbon fiber composite materials, and in particular relates to a multi-layer fiber prepreg and a preparation method and a production device thereof. Background Art
[0002] Fiber-reinforced resin-based composite materials are currently widely used in aerospace, rail transportation, sports equipment and other fields. The current composite material market has been developing steadily and rapidly. Fiber prepreg is a widely used intermediate product in the field of composite materials. Compared with other molding methods, the parts prepared by prepreg have a stable resin content and a high fiber mass fraction, which can ensure the stable performance of the final parts.
[0003] Currently, due to the influence of raw materials and molding equipment, heavy-weight prepregs (including carbon fiber unidirectional prepregs, carbon fiber fabric prepregs, multi-axial warp knitted fabric prepregs, etc.) have poor resin impregnation, resulting in some dry yarns in the reinforcing materials in the prepregs, which will cause defects such as delamination or localized intensive bubbles in the final parts, thus affecting the use of the final parts. Therefore, the load-bearing parts in aerospace, military equipment, rail transportation, and high-end sports and leisure products are mostly formed by prepreg autoclave molding or prepreg compression molding. In the use of prepreg molding technology, when the thickness of the part is constant, the number of small-weight prepreg layers is large, resulting in a large amount of human resources consumed in the laying process and affecting the molding efficiency of the parts. Summary of the invention
[0004] In view of the above problems existing in the prior art, the present invention provides a multi-layer fiber prepreg and a preparation method and a production device thereof, which can continuously produce fiber prepreg with large gram weight and high impregnation degree online.
[0005] To achieve the above object, the technical solution provided by the present invention is as follows:
[0006] In a first aspect, the present application provides a method for preparing a multilayer fiber prepreg, comprising the following steps: adding N layers of reinforcing material to the surface layer of a single-layer fiber prepreg produced online, and adding a layer of resin film for each added layer of reinforcing material, to obtain the multilayer fiber prepreg, wherein N≥1.
[0007] Optionally, a layer of reinforcing material and a corresponding layer of resin film are formed as a group, and after each group of materials is added on a single layer of fiber prepreg, an impregnation treatment is performed before adding the next group.
[0008] Optionally, the single-layer fiber prepreg is prepared by impregnating the reinforcing material into upper and lower layers of resin films.
[0009] Optionally, the temperature of the impregnation roller in the preparation process of the single-layer fiber prepreg is 80-90°C and the roller pressure is 0.1-0.2MPa; the temperature of the impregnation roller after each additional group of materials is 90-100°C and the roller pressure is 0.3-0.4MPa.
[0010] Optionally, the reinforcing material is unidirectional fiber or fiber fabric.
[0011] Optionally, the reinforcing material is carbon fiber, glass fiber or aramid fiber.
[0012] Optionally, the carbon fibers are polyacrylonitrile-based, asphalt-based or viscose-based carbon fibers.
[0013] Optionally, the resin film is a thermosetting resin.
[0014] Optionally, the resin film is epoxy resin, bismaleimide resin, cyanate resin or phenolic resin.
[0015] Optionally, the reinforcing materials between different layers in the multi-layer fiber prepreg are the same or different.
[0016] Optionally, at least one layer of the reinforcing materials between different layers of the multi-layer fiber prepreg is unidirectional fiber.
[0017] In a second aspect, the present application also provides a multi-layer fiber prepreg prepared according to the method of the first aspect, wherein the multi-layer fiber prepreg has a gram weight of 300-600 g / m 2 , the resin mass content is 25%-50%.
[0018] In the third aspect, the present application also provides a production equipment for the multilayer fiber prepreg described in the second aspect, comprising a first group of film unwinding devices, a first reinforcement material unwinding device and a winding device, the discharge ends of the first group of film unwinding devices and the first reinforcement material unwinding device are connected with a first impregnation component, at least one group of reinforcement material laying components is arranged between the discharge end of the first impregnation component and the winding device, and at least one group of reinforcement material laying components are connected in sequence, the reinforcement material laying component comprises a second traction roller and a second impregnation component arranged at the discharge end of the second traction roller, the discharge end of the second traction roller is also provided with a release paper winding device, and the feed end of the second impregnation component is also provided with a second reinforcement material unwinding device and a second resin film unwinding device.
[0019] Compared with the prior art, this application has at least the following beneficial effects:
[0020] The present invention adds N layers of reinforcing materials on the surface of the single-layer fiber prepreg produced online, and each additional layer of reinforcing material corresponds to an additional layer of resin film, and the additional reinforcing materials and the resin film are impregnated, and the impregnation temperature and pressure of the single-layer fiber prepreg preparation process and the impregnation temperature and pressure of the additional reinforcing materials are controlled, so that large-weight and high-impregnation fiber prepregs can be produced online quickly and efficiently, and the stability and mechanical properties of the obtained multi-layer prepregs are greatly improved compared with the conventional large-weight prepregs obtained by prepreg pressing, which solves the problem of low impregnation degree in the preparation of large-weight prepregs; there is no need to roll up the single-layer fiber prepreg, and the required weight prepreg can be directly customized online as needed. The impregnation temperature of the single-layer fiber prepreg preparation process is low, and the impregnation temperature of the additional reinforcing materials is high, so that the balance of upper and lower impregnation is good.
[0021] When using the conventional two-film process to produce heavy-weight prepregs, the impregnation degree is less than level 4. When using this process to prepare prepregs (using the same resin film and reinforcing fiber), under the condition of the same fiber surface density, the impregnation degree is ≥ level 5. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 This is a schematic diagram of the structure of a production device for multi-layer fiber prepreg in an embodiment of the present application;
[0023] Description of reference numerals:
[0024] 1. First upper film unwinding device; 2. First lower film unwinding device; 3. First reinforcement material unwinding device; 4. First impregnation roller A; 5. First heating plate; 6. First impregnation roller B; 7. First cooling plate; 8. Second traction roller; 9. Release paper winding device; 10. Second reinforcement material unwinding device; 11. Second resin film unwinding device; 12. Second impregnation roller A; 13. Second heating plate; 14. Second impregnation roller B; 15. Second cooling plate; 16. Third traction roller; 17. Second release paper winding device; 18. PE film unwinding device; 19. PE film laminating roller; 20. Winding device. DETAILED DESCRIPTION
[0025] The present invention is further described in detail below in conjunction with the accompanying drawings:
[0026] The experimental methods used in the embodiments of the present invention are conventional methods unless otherwise specified.
[0027] The reagents and materials used in this example can all be purchased conventionally. The quantitative experiments involved in the examples were repeated at least three times, and the results were averaged.
[0028] Example
[0029] A production device for multi-layer fiber prepreg, the structure of which is as follows Figure 1As shown, it includes a first group of film unwinding devices, a first reinforcing material unwinding device 3 and a winding device 20. The first group of film unwinding devices includes a first upper film unwinding device 1 and a first lower film unwinding device 2. The discharge ends of the first upper film unwinding device 1, the first lower film unwinding device 2 and the first reinforcing material unwinding device 3 are connected with a first impregnation component. At least one group of reinforcing material laying components is arranged between the discharge end of the first impregnation component and the winding device 20. At least one group of reinforcing material laying components are connected in sequence. The number of groups of reinforcing material laying components can be selected as needed. In this embodiment, a group of reinforcing material laying components is arranged between the discharge end of the first impregnation component and the winding device 20. The reinforcing material laying component includes a second traction roller 8 and a second impregnation component arranged at the discharge end of the second traction roller 8. The discharge end of the second traction roller 8 is also provided with a release paper winding device 9. The feed end of the second impregnation component is also provided with a second reinforcing material unwinding device 10 and a second resin film unwinding device 11.
[0030] The first impregnation assembly includes a first impregnation roller A4, a first heating plate 5, three groups of first impregnation rollers B6, and a first cooling plate 7 which are connected in sequence; the discharge ends of the first upper film unwinding device 1, the first lower film unwinding device 2 and the first reinforcing material unwinding device 3 are connected to the first impregnation roller A4; the discharge end of the first cooling plate 7 is connected to the feed end of the second traction roller 8.
[0031] The second impregnation assembly includes two groups of second impregnation rollers A12, a second heating plate 13, three groups of second impregnation rollers B14 and a second cooling plate 15 connected in sequence; the discharge end of the second traction roller 8, the second reinforcement material unwinding device 10, and the second resin film unwinding device 11 are connected to the feed end of the second impregnation roller A12 in front; the discharge end of the second cooling plate 15 is connected to the third traction roller 16, and the discharge end of the third traction roller 16 is connected to the second release paper winding device 17 and the PE film lamination roller 19, and the feed end of the PE film lamination roller 19 is also connected to the PE film unwinding device 18, and the discharge end of the PE film lamination roller 19 is connected to the winding device 20.
[0032] The preparation method of multi-layer fiber prepreg using the above production equipment comprises the following steps:
[0033] First, the upper and lower resin films and the first reinforcing material are led out from the discharge ends of the first upper film unwinding device 1, the first lower film unwinding device 2 and the first reinforcing material unwinding device 3, and the upper resin film and the lower resin film are respectively compounded with the upper and lower surfaces of the first reinforcing material, and then passed through the first impregnation roller A4, and the upper resin film and the lower resin film are melted and impregnated into the reinforcing material by the temperature and pressure of the first impregnation roller A4, and then cooled by the first heating plate 5, three groups of first impregnation rollers B6, and the first cooling plate 7 in sequence to obtain a single-layer fiber prepreg;
[0034] The single-layer fiber prepreg moves under the traction of the second traction roller 8, and after peeling off the upper release paper, it is combined with the second reinforcement material and the second resin film led out by the second reinforcement material unwinding device 10 and the second resin film unwinding device 11 (the second reinforcement material is between the second resin film and the single-layer fiber prepreg), and enters the two groups of second impregnation rollers A12 for impregnation, and then passes through the second heating plate 13, three groups of second impregnation rollers B14 and the second cooling plate 15 in sequence, and is led out by the third traction roller 16, and then is wound up by the upper release paper again, combined with the PE film led out by the PE film unwinding device 18 and enters the PE film laminating roller 19 for lamination, and finally is wound up by the winding device 20 to obtain a multi-layer fiber prepreg.
[0035] The temperature of the first impregnation roller A and the first impregnation roller B is 80-90°C, and the roller pressure is controlled at 0.1-0.2Mpa;
[0036] The temperature of the second impregnation roller A and the second impregnation roller B is controlled between 90-100° C., and the roller pressure is controlled between 0.3-0.4 MPa.
[0037] The temperature of the first heating plate 5 is 85-95°C, the temperature of the first cooling plate 7 is 18±3°C; the temperature of the second heating plate 13 is 95-105°C, the temperature of the second cooling plate 15 is 18±3°C.
[0038] The production speed is 3m / min, winding.
[0039] Among them, the first reinforcement material uses Hengshen HF30F-12K fiber, and the fiber surface density is 150g / m 2 The second reinforcement material uses Hengshen HFW220T twill fabric with a fiber surface density of 220g / m 2 The upper film, lower film and second resin film of the first group of resin films are all made of medium-temperature curing epoxy resin from Hengshen Company, with a gram weight of 124g / m 2 , 73g / m 2 , 50g / m 2 .
[0040] The resin content of the obtained multi-layer fiber prepreg is controlled to be 40±3%, and the total fiber surface density is 370g / m 2 .
[0041] The conventional two-film method (the upper film and the lower film are impregnated with reinforcing material in between) uses a prepreg prepared with the same resin film and reinforcing material as in the present application, or a prepreg obtained by pressing a single layer of prepreg. Under the same condition as the prepreg fiber surface density in the present application, it is difficult to achieve an impregnation degree of level 4. The multi-layer fiber prepreg prepared by the preparation method in the present application can reach an impregnation degree of more than level 5, which greatly improves the impregnation degree of the prepreg and reduces the problems of bulging and wrinkling of the prepreg caused by low impregnation degree.
[0042] The impregnation test method in this application is:
[0043] 1. Cut the carbon fiber unidirectional prepreg with a size of 20cm*5cm (20cm is the width dimension of the prepreg, and 5cm is the length dimension of the prepreg);
[0044] 2. Tear off the protective film or release paper on the upper and lower surfaces of the prepreg, stick the upper and lower surfaces with pressure-sensitive tape, and compact them;
[0045] 3. Tear the pressure-sensitive tape with force, and determine the impregnation degree based on the remaining fibers of the upper and lower pressure-sensitive tapes. The higher the impregnation degree, the higher the degree of impregnation of the prepreg. See Table 1 for the impregnation degree evaluation standard.
[0046] Table 1 Evaluation criteria for impregnation cost
[0047] degree of impregnation Judgment criteria Level 2 The prepreg is severely delaminated (≥10cm), the fibers are clustered and dry Level 3 The prepreg is severely delaminated (≥10cm), the hair is gathered and dry Level 4 The prepreg sample has delamination between one quarter and half of the sample length (5cm-10cm), with a lot of filaments but not dry Level 5 The prepreg sample has delamination within a quarter of the sample length (≤5cm), but there are more hairs and it is dry. Level 6 The prepreg sample has delamination within a quarter of the sample length (≤5cm), but the hair is less and dry
Claims
1. A method for preparing a multilayer fiber prepreg, characterized in that: The method comprises the following steps: adding N layers of reinforcing material to the surface of the single-layer fiber prepreg produced online, adding a layer of resin film for each added layer of reinforcing material, to obtain the multi-layer fiber prepreg, wherein N≥1.
2. The method for preparing a multilayer fiber prepreg according to claim 1, characterized in that: A layer of reinforcing material and a corresponding layer of resin film are formed as a group. After each group of materials is added on the single-layer fiber prepreg, an impregnation treatment is performed before adding the next group.
3. The method for preparing a multilayer fiber prepreg according to claim 2, characterized in that: The single-layer fiber prepreg is prepared by impregnating the reinforcing material into the upper and lower layers of resin adhesive films.
4. The method for preparing a multilayer fiber prepreg according to claim 3, characterized in that: The temperature of the impregnation roller in the preparation process of the single-layer fiber prepreg is 80-90°C and the roller pressure is 0.1-0.2MPa; the temperature of the impregnation roller after each additional group of materials is 90-100°C and the roller pressure is 0.3-0.4MPa.
5. The method for preparing a multilayer fiber prepreg according to claim 1, characterized in that: The reinforcing material is unidirectional fiber or fiber fabric.
6. The method for preparing a multilayer fiber prepreg according to claim 1, characterized in that: The resin film is a thermosetting resin.
7. The method for preparing a multilayer fiber prepreg according to claim 1, characterized in that: The reinforcing materials between different layers in the multi-layer fiber prepreg are the same or different.
8. The method for preparing a multilayer fiber prepreg according to claim 1, characterized in that: At least one layer of the reinforcing materials between different layers of the multi-layer fiber prepreg is unidirectional fiber.
9. The multilayer fiber prepreg prepared by the method according to any one of claims 1 to 8, characterized in that: The multi-layer fiber prepreg has a gram weight of 300-600 g / m 2 , the resin mass content is 25%-50%.
10. A production device for the multi-layer fiber prepreg as claimed in claim 9, characterized in that: It includes a first upper film unwinding device, a first reinforcing material unwinding device, a first lower film unwinding device and a winding device. The discharge ends of the first upper film unwinding device, the first lower film unwinding device and the first reinforcing material unwinding device are connected with a first impregnation component. At least one group of reinforcing material laying components is arranged between the discharge end of the first impregnation component and the winding device. The at least one group of reinforcing material laying components are connected in sequence. The reinforcing material laying component includes a second traction roller and a second impregnation component arranged at the discharge end of the second traction roller. The discharge end of the second traction roller is also provided with a release paper winding device. The feed end of the second impregnation component is also provided with a second reinforcing material unwinding device and a second resin film unwinding device.