Prepreg sample preparation device and sample preparation method

Abstract

The invention discloses a prepreg sample preparation device and a prepreg sample preparation method, belongs to the technical field of prepreg performance analysis and test, and can solve the problems that the content of each component of a manually-manufactured prepreg test sample is inaccurate, the test result precision is relatively low, and the sample preparation efficiency is low. A cooling mechanism of the prepreg sample preparation device is configured to cool a prepreg placed in the cooling mechanism until resin contained in the prepreg is converted into a vitrification state to obtain a cooled prepreg; the cutting platform is configured to place the cooled prepreg; the cutting mechanism is arranged above the cutting platform and is configured to cut the cooled prepreg to obtain a prepreg test sample; the material taking cup is arranged below the material cutting opening of the material cutting platform and is configured to contain a prepreg test sample. According to the prepreg test sample prepared by the invention, the content of each component is more accurate, and the accuracy of an analysis test result and the efficiency of a sample preparation process are improved.

Description

Technical Field

[0001] This application relates to the technical field of prepreg performance analysis and testing, and particularly relates to a prepreg sample preparation device and a sample preparation method. Background Art

[0002] Prepregs are widely used in fields such as aerospace, wind power, automobiles, and sports equipment. Due to their excellent performance, prepregs occupy an important position in modern composite material manufacturing. A prepreg refers to a composite made by impregnating a resin matrix into continuous fibers or fabrics under strictly controlled conditions. Among them, the resin includes thermosetting resins and thermoplastic resins. The fibers include carbon fibers, glass fibers, aramid fibers, etc.

[0003] Currently, the main characterization methods for prepregs include infrared analysis (FTIR), differential scanning calorimetry analysis (DSC), thermogravimetric analysis (TGA), etc. These characterization methods have specific requirements for prepreg test samples. Taking differential scanning calorimetry (DSC) as an example, the weight of the test sample needs to be 5 mg to 15 mg, and the weighing accuracy reaches 0.01 mg. The weighing accuracy of the sample is crucial for the accuracy of the test results.

[0004] At room temperature, the viscosity of prepregs is relatively high. When using tools such as scissors and tweezers to manually make extremely small prepreg test samples, the resin in the prepreg is likely to adhere to the sample preparation tools, and the efficiency of the sample preparation process is relatively low. Even some parts are separated from the prepreg, resulting in changes in the resin-to-fiber ratio in the prepared extremely small prepreg test samples, and the content of each component in the prepreg test sample is inaccurate. The resin distribution on the same roll of prepreg is not absolutely uniform. Taking extremely small amounts of prepregs to make prepreg test samples leads to certain differences in the content of each component between different prepreg test samples. For analysis and testing techniques that take extremely small prepreg test samples such as differential scanning calorimetry (DSC), the differences in the content of each component between each prepreg test sample cannot be ignored, resulting in poor representativeness of the test results of a single prepreg test sample, certain discreteness in multiple groups of test results, and low accuracy. Based on the above situation, it is necessary to greatly increase the number of prepreg test samples for testing and take the average value of the test results, which greatly increases the analysis and testing costs. Summary of the Invention

[0005] By providing a prepreg sample preparation device and method in an embodiment of this application, it is possible to solve the problems of inaccurate content of each component in manually made prepreg test samples, low accuracy of test results, and low sample preparation efficiency.

[0006] To achieve the above object, the technical solution of the embodiment of the present invention is as follows:

[0007] In a first aspect, an embodiment of the present invention provides a prepreg sample preparation device, which includes a cooling mechanism, a cutting platform, a cutting mechanism, and a material taking cup;

[0008] The cooling mechanism is configured to cool the prepreg placed therein until the resin contained in the prepreg is converted into a vitrified state to obtain a cooled prepreg;

[0009] The cutting platform is configured to place the cooled prepreg;

[0010] The cutting mechanism is arranged above the cutting platform and is configured to cut the cooled prepreg to obtain a prepreg test sample;

[0011] The material taking cup is arranged below the cutting opening of the cutting platform and is configured to receive the prepreg test sample.

[0012] In combination with the first aspect, in a possible implementation manner, the prepreg sample preparation device further includes a fixture mechanism;

[0013] The fixture mechanism is configured to place the prepreg and then place it in the cooling mechanism for cooling to obtain the cooled prepreg, and transfer the cooled prepreg to the cutting platform and push it forward at a preset speed for cutting.

[0014] In combination with the first aspect, in a possible implementation manner, the fixture mechanism includes a bearing box, a partition board, a pushing component, a fixing piece, and a handle;

[0015] The bearing box is a hexahedron, and at least one side is provided with an opening;

[0016] The partition board is clamped in the middle of the bearing box, and a through groove is provided in the middle, and the extending direction of the through groove is perpendicular to the opening;

[0017] At least one side of the bearing box parallel to the extending direction of the through groove above the partition board is provided with a window;

[0018] A plurality of first through holes are provided on the top plate and bottom plate of the bearing box and the partition board;

[0019] The pushing component includes a control rod, a connecting rod, and a pushing rod;

[0020] The two ends of the connecting rod are respectively fixed with the control rod and the pushing rod, and the control rod and the pushing rod are parallel;

[0021] The pushing component is arranged in the bearing box; the control rod is located above the partition board, and at least one end extends out of the window of the bearing box; the pushing rod is arranged below the partition board; the connecting rod is clamped in the through groove and can move along the through groove;

[0022] The fixing member is inserted into one end of the through groove close to the opening.

[0023] The handle includes at least one, and at least one handle is arranged on the top surface of the carrying box.

[0024] In combination with the first aspect, in a possible implementation manner, the cooling mechanism includes a cooling box, a lower pressing plate, a first support rod, a first elastic member, an upper pressing plate, a fixing rod and a box cover;

[0025] A plurality of second through holes are uniformly distributed on the lower pressing plate;

[0026] The first support rod includes at least one, and at least one first support rod passes through the lower pressing plate so that the lower pressing plate can slide along the first support rod;

[0027] Both the first support rod and the lower pressing plate are arranged in the cooling box;

[0028] The first elastic member is arranged between the lower pressing plate and the bottom surface of the cooling box;

[0029] The bottom of the fixing rod is fixedly provided with the upper pressing plate, and the top is fixedly provided with the box cover.

[0030] In combination with the first aspect, in a possible implementation manner, the cutting platform includes a first sub-platform and a second sub-platform;

[0031] The first sub-platform and the second sub-platform are arranged in parallel at intervals, and a cutting port is formed at the interval.

[0032] In combination with the first aspect, in a possible implementation manner, the prepreg sample preparation device further includes a drying mechanism;

[0033] The first sub-platform includes a hexahedron and a placement plate;

[0034] The placement plate is inserted into the middle of the hexahedron;

[0035] The drying mechanism is arranged on the bottom surface of the hexahedron.

[0036] In combination with the first aspect, in a possible implementation manner, the cutting mechanism includes a cutting blade, a fixing plate, a second support rod, a second elastic member and a driving component;

[0037] The top of the cutting blade is fixedly provided with the fixing plate;

[0038] The second support rod includes at least one, and the lower end of at least one second support rod is arranged on the cutting platform and passes through the fixing plate so that the fixing plate can slide along the second support rod;

[0039] The second elastic member is disposed between the material cutting platform and the fixed plate;

[0040] The driving assembly is connected to the fixed plate to drive the fixed plate to move up and down, and further drive the cutting blade to cut the cooled prepreg at the material cutting port.

[0041] In combination with the first aspect, in a possible implementation manner, the driving assembly includes a motor, a cam, a first link shaft, a first link, a second link shaft, and a hinge seat;

[0042] The cam is sleeved on the output shaft of the motor;

[0043] One end of the first link shaft is disposed on the cam, and the other end is connected to one end of the first link;

[0044] The second link shaft passes through the other end of the first link, and both ends are hinged to the hinge seat;

[0045] The hinge seat is fixedly disposed on the top surface of the fixed plate.

[0046] In combination with the first aspect, in a possible implementation manner, the material taking cup includes a cup body, a second handle, and a stirring assembly;

[0047] The cup body is in the shape of a frustum of a pyramid;

[0048] The second handle is disposed on the side surface of the cup body;

[0049] The stirring assembly is configured to stir the inner cavity of the cup body.

[0050] In a second aspect, another embodiment of the present invention provides a prepreg sample preparation method, based on the prepreg sample preparation device described above, including:

[0051] Cool the prepreg placed in the cooling mechanism until the resin contained in the prepreg is converted into a vitrified state to obtain a cooled prepreg;

[0052] Place the cooled prepreg on the material cutting platform;

[0053] Cut the cooled prepreg through a cutting mechanism disposed above the material cutting platform to obtain a prepreg test sample;

[0054] Collect the prepreg test sample through the material taking cup below the material cutting port of the material cutting platform.

[0055] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages:

[0056] The prepreg sample preparation device provided by the embodiment of the present invention, during actual use, first cools the prepreg placed in the cooling mechanism until the resin contained in the prepreg is converted into a vitrified state to obtain a cooled prepreg. Then, the cooled prepreg is placed on the cutting platform. After that, the cutting mechanism arranged above the cutting platform cuts the cooled prepreg to obtain a prepreg test sample. Finally, the prepreg test sample is collected by the sampling cup below the cutting opening of the cutting platform. The cooled prepreg obtained by cooling the prepreg, since the resin contained in the prepreg is converted into a vitrified state, is transformed from a soft fibrous cloth state at room temperature into a hard thin plate state, reducing the viscosity of the prepreg. When cutting the cooled prepreg to obtain a prepreg test sample, it is easy to cut. Since the resin in the cooled prepreg hardens, it will not adhere to the sample preparation tool during cutting, so that the resin will not separate from the prepreg, resulting in a change in the resin-to-fiber ratio in the extremely small prepreg test sample obtained by cutting. The content of each component in the prepreg test sample is more accurate. For analysis and testing techniques that take very little prepreg test sample, such as differential scanning calorimetry (DSC), the test results of a single prepreg test sample are also more accurate. There is no need to greatly increase the number of prepreg test samples for testing, which can reduce the analysis and testing costs, improve the efficiency of the sample preparation process, and reduce the process impact. In addition, by mechanically cutting the prepreg with the cutting mechanism, smaller prepreg test samples can be obtained, and at the same time, the consistency of the resin-to-fiber ratio between a single prepreg test sample and the entire roll of prepreg can be improved, thereby improving the accuracy of the analysis and testing results. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments of the present invention. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0058] Figure 1 Structural schematic of the prepreg sample preparation device provided by the embodiment of the present application Figure 1 ;

[0059] Figure 2 Structural schematic of the prepreg sample preparation device provided by the embodiment of the present application Figure 2 ;

[0060] Figure 3 Structural schematic of the prepreg sample preparation device provided by the embodiment of the present application Figure 3 ;

[0061] Figure 4 Structural schematic of the prepreg sample preparation device provided by the embodiment of the present application Figure 4 ;

[0062] Figure 5 Structural schematic of the prepreg sample preparation device provided by the embodiment of the present application Figure 5 ;

[0063] Figure 6 Structural schematic of the prepreg sample preparation device provided by the embodiment of the present application Figure 6 ;

[0064] Figure 7 Structural schematic of the fixture mechanism provided by the embodiment of the present application Figure 1 ;

[0065] Figure 8 Structural schematic of the fixture mechanism provided by the embodiment of the present application Figure 2 ;

[0066] Figure 9 Structural schematic of the fixture mechanism provided by the embodiment of the present application Figure 3 ;

[0067] Figure 10 Structural schematic of the fixture mechanism provided by the embodiment of the present application Figure 4 ;

[0068] Figure 11 Structural schematic of the material taking cup provided by the embodiment of the present application Figure 1 ;

[0069] Figure 12 Structural schematic of the material taking cup provided by the embodiment of the present application Figure 2 .

[0070] Icons: 1 - Cooling mechanism; 11 - Cooling box; 12 - Lower pressing plate; 121 - Second through hole; 13 - First support rod; 14 - First elastic member; 15 - Upper pressing plate; 151 - Third through hole; 16 - Fixed rod; 17 - Box cover; 18 - Third handle; 2 - Cutting platform; 21 - First sub-platform; 211 - Placing plate; 212 - Limiting strip; 22 - Second sub-platform; 221 - Avoidance groove; 23 - Guide plate; 24 - Guide rail; 3 - Cutting mechanism; 31 - Cutting blade; 32 - Fixed plate; 33 - Second support rod; 34 - Second elastic member; 35 - Driving assembly; 351 - Motor; 352 - Cam; 353 - First connecting rod shaft; 354 - First connecting rod; 355 - Second connecting rod shaft; 356 - Hinge seat; 36 - Support frame; 37 - Protective cover; 4 - Material taking cup; 41 - Cup body; 42 - Second handle; 43 - Stirring assembly; 431 - Handle; 432 - Second connecting rod; 433 - Main shaft; 434 - Material turning plate; 44 - Groove; 5 - Clamping mechanism; 51 - Carrying box; 511 - Window; 52 - Partition plate; 521 - First through hole; 53 - Pushing assembly; 531 - Control rod; 532 - Connecting rod; 533 - Pushing rod; 54 - Fixed part; 55 - Handle; 56 - Positioning strip; 57 - Limiting assembly; 571 - U-shaped clamp; 572 - Limiting bolt; 58 - Sleeve; 59 - Driving rod; 50 - Linear motor; 6 - Drying mechanism; 7 - Prepreg. Detailed implementation manners

[0071] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0072] In the description of the embodiments of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of 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. Therefore, it should not be construed as a limitation to the present invention. The terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. In addition, the terms "mounted", "connected", "connected to" 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0073] Please refer to Figures 1 - 6 As shown, the embodiments of the present invention provide a prepreg sample preparation device, including a cooling mechanism 1, a cutting platform 2, a cutting mechanism 3, and a sampling cup 4. The cooling mechanism 1 is configured to cool the prepreg 7 placed therein until the resin contained in the prepreg 7 is converted into a vitrified state to obtain a cooled prepreg. At this time, the cooled prepreg becomes hard, brittle, and loses its viscosity, reaching the cutting condition.

[0074] The cutting platform 2 is configured to place the cooled prepreg. The cutting mechanism 3 is arranged above the cutting platform 2 and is configured to cut the cooled prepreg to obtain a prepreg test sample. The sampling cup 4 is arranged below the cutting opening of the cutting platform 2 and is configured to receive the prepreg test sample.

[0075] The prepreg sample preparation device provided by the embodiment of the present invention, during actual use, first cools the prepreg 7 placed in the cooling mechanism 1 until the resin contained in the prepreg 7 is converted into a vitrified state to obtain a cooled prepreg. Then the cooled prepreg is placed on the cutting platform 2. After that, the cutting mechanism 3 arranged above the cutting platform 2 cuts the cooled prepreg to obtain prepreg test samples. Finally, the prepreg test samples are collected by the sampling cup 4 below the cutting opening of the cutting platform 2. The cooled prepreg obtained by cooling the prepreg 7, since the resin contained in the prepreg 7 is converted into a vitrified state, changes from a soft fibrous cloth state at room temperature to a hard thin plate state, reducing the viscosity of the prepreg 7. When cutting the cooled prepreg to obtain prepreg test samples, it is easy to cut. Since the resin in the cooled prepreg hardens, it will not adhere to the sample preparation tool during cutting, so that the resin will not separate from the prepreg 7 and cause changes in the resin-to-fiber ratio in the extremely small prepreg test samples obtained by cutting. The content of each component of the prepreg test sample is more accurate. For analysis and testing techniques that take very few prepreg test samples, such as differential scanning calorimetry (DSC), the test results of a single prepreg test sample are also more accurate. There is no need to greatly increase the number of prepreg test samples for testing, which can reduce the analysis and testing costs, improve the efficiency of the sample preparation process, and reduce the process impact. In addition, by mechanically cutting the prepreg 7 with the cutting mechanism, finer prepreg test samples are obtained, and at the same time, the consistency of the resin-to-fiber ratio between a single prepreg test sample and the entire roll of prepreg can be improved, thereby improving the accuracy of the analysis and testing results.

[0076] Continue to refer to Figures 1 - 6 As shown, the prepreg sample preparation device further includes a fixture mechanism 5. The fixture mechanism 5 is configured to place the prepreg 7 and then place it in the cooling mechanism 1 for cooling to obtain a cooled prepreg, and transfer the cooled prepreg to the cutting platform 2 and push it forward at a preset speed for cutting.

[0077] In practice, the cooled prepreg is a thin sheet and is easily brittle after cooling. By placing the prepreg 7 with the fixture mechanism 5 and then placing it in the cooling mechanism 1 for cooling to obtain a cooled prepreg, and transferring the cooled prepreg to the cutting platform 2 and pushing it forward at a preset speed for cutting, the integrity of the cooled prepreg can be ensured, and the influence of human damage on the content of each component of the obtained prepreg test sample can be reduced. Of course, the cooled prepreg can also be manually taken for transfer and advancement.

[0078] As Figures 7 - 10 shown, the fixture mechanism 5 includes a carrying box 51, a partition plate 52, a pushing component 53, a fixing part 54, and a handle 55.

[0079] The carrying box 51 is a hexahedron, and at least one side is provided with an opening. As Figures 7 - 9As shown, an opening is provided on the right side of the carrier box 51. Of course, an opening can also be provided on the left side of the carrier box 51.

[0080] The partition plate 52 is clamped in the middle of the carrier box 51, and a through groove is provided in the middle. The extending direction of the through groove is perpendicular to the opening. In practice, the partition plate 52 can include two partition sub - plates, which are respectively clamped in the middle of the carrier box 51, and a through groove is formed between the two partition sub - plates. The partition plate 52 divides the inner cavity of the carrier box 51 into an upper cavity and a lower cavity.

[0081] At least one side of the carrier box 51 parallel to the extending direction of the through groove, in the part above the partition plate 52, is provided with a window 511. As Figure 8 and Figure 9 show a schematic structural diagram of the two sides of the carrier box 51 parallel to the extending direction of the through groove, in the part above the partition plate 52, being provided with windows 511.

[0082] A plurality of first through - holes 521 are provided on the top plate and bottom plate of the carrier box 51 and on the partition plate 52. As Figures 7 - 9 shows a schematic structural diagram of the top plate of the carrier box 51 being provided with twenty - five rectangular first through - holes 521 arranged in five rows and five columns.

[0083] As Figure 9 shown, the pushing component 53 includes a control rod 531, a connecting rod 532, and a pushing rod 533.

[0084] The two ends of the connecting rod 532 are respectively fixed with the control rod 531 and the pushing rod 533, and the control rod 531 and the pushing rod 533 are parallel, so that the pushing component 53 forms an "I" shape, and the length of the control rod 531 is greater than the length of the pushing rod 533.

[0085] The pushing component 53 is arranged in the carrier box 51. The control rod 531 is located above the partition plate 52, and at least one end extends out of the window 511 of the carrier box 51. When one side of the carrier box 51 parallel to the extending direction of the through groove, in the part above the partition plate 52, is provided with a window 511, the end of the control rod 531 located at the window 511 extends out of the window 511 of the carrier box 51. When both sides of the carrier box 51 parallel to the extending direction of the through groove, in the part above the partition plate 52, are provided with windows 511, the control rod 531 can extend out of the corresponding window 511 of the carrier box 51 at one end or both ends.

[0086] The length of the pushing rod 533 is shorter than the width of the carrier box 51 ( Figure 9In the direction of the OY axis, the pusher rod 533 is arranged below the partition plate 52. The connecting rod 532 is clamped in the through groove and can move along the through groove. The fixing member 54 is inserted into one end of the through groove close to the opening. The fixing member 54 can be a nut. In practice, the groove wall at one end of the through groove close to the opening is recessed to form a concave arc, and threads are formed on the concave arcs on the two side walls of the through groove to form threaded holes. The nut is arranged in the threaded holes, and by turning the nut, the relative distance between the lower end of the nut and the bottom plate of the bearing box 51 can be adjusted.

[0087] The handle 55 includes at least one, and at least one handle 55 is arranged on the top surface of the bearing box 51. As Figures 7 - 9 shown in the structural schematic diagram where the handle 55 includes two. The two handles 55 are sheet-shaped and are arranged in parallel on both sides of the top plate of the bearing box 51.

[0088] When the fixture mechanism 5 provided by the embodiment of the present invention is actually used, the pusher assembly 53 is arranged in the bearing box 51, the control rod 531 is located above the partition plate 52, at least one end of the control rod 531 extends out of the window 511 of the bearing box 51, the pusher rod 533 is arranged below the partition plate 52, and the connecting rod 532 is clamped in the through groove and can move along the through groove. When loading the prepreg 7 into the fixture mechanism 5, the control rod 531 is pushed to move towards the end away from the opening of the bearing box 51, so that the fixing member 54 moves upward. As Figure 8 shown, the prepreg 7 is placed on the bottom plate of the bearing box 51, in the lower cavity of the bearing box 51, and the side surface of the pusher rod 533 can be attached to the end surface of the prepreg 7. The fixing member 54 is inserted into one end of the through groove close to the opening, so that the fixing member 54 moves downward (if the fixing member 54 is a nut, just turn the nut to move downward), so that the front end of the fixing member 54 fixes the prepreg 7 to prevent the prepreg 7 from coming out and shaking. Then the operator holds the handle 55 and places the fixture mechanism 5 containing the prepreg 7 into the cooling mechanism 1 for cooling to obtain the cooled prepreg.

[0089] After that, the operator takes out the clamp mechanism 5 holding the prepreg 7 from the cooling mechanism 1 by lifting the handle 55, and transfers the clamp mechanism 5 to the corresponding position of the cutting platform 2, and then moves the fixing member 54 upward (if the fixing member 54 is a nut, just twist the nut to move it upward) to release the cooling prepreg, and the fixing member 54 moves to a relative distance from the bottom plate of the carrying box 51 to a state where the cooling prepreg can be pushed out but is not completely loose, and stops moving. This ensures that the cooling prepreg can be pushed out smoothly when it is cut, and the cooling prepreg is pressed and will not warp. At this time, the clamp mechanism 5 also has the function of pressing the cooling prepreg to prevent it from warping during the cutting process. Since the control rod 531 and the push rod 533 are respectively fixed at both ends of the connecting rod 532, and the control rod 531 and the push rod 533 are parallel, the control rod 531 is located above the partition plate 52, and at least one end extends out of the window 511 of the supporting box 51, and the push rod 533 is arranged below the partition plate 52. The connecting rod 532 is clamped in the through groove and can move along the through groove. By pushing the control rod 531 at a preset speed, the push assembly 53 can move at a preset speed, so that the push rod 533 pushes the prepreg 7 at a preset speed for cutting.

[0090] Continue to refer to Figures 7 - 10 As shown, the clamp mechanism 5 also includes a positioning bar 56. The positioning bar 56 is arranged above the window 511 and extends along the length direction of the carrying box 51. The positioning bar 56 has a linear array of concave and convex structures along the length direction, and the width of the concave and convex structures is ≤5mm ( Figures 7 - 9 When the operator manually moves the control rod 531 of the pusher assembly 53, the operator can touch the concave-convex structure, which is convenient for accurately controlling the moving distance of the pusher assembly 53 during the process of pushing and pulling the control rod 531, thereby controlling the pushing speed of the pusher assembly 53. The concave-convex structure also increases the friction between the fingers during the process of pushing and pulling the pusher assembly 53, and manually controls the feeding speed to a certain extent, preventing the control rod 531 from slipping and causing feeding beyond the cutting width.

[0091] Furthermore, a scale is provided below the window 511 along the length direction of the carrying box 51 , and the scale accuracy is 1 mm, so as to facilitate observation of the advancement distance of the pushing assembly 53 .

[0092] Optionally, the clamp mechanism 5 further includes a limiting assembly 57. The limiting assembly 57 includes a U-shaped clip 571 and a limiting bolt 572. The U-shaped clip 571 is clamped on a side of the window 511 of the carrier box 51 close to the opening, and then the limiting bolt 572 passes through the outward side wall of the U-shaped clip 571 and abuts against the window 511 (specifically, against the recess of the positioning strip 56 of the window 511). In practice, when the control rod 531 of the push assembly 53 moves into place, the limiting assembly 57 limits the push rod 533 from continuing to move, and the feeding length of the push assembly 53 can be controlled.

[0093] Furthermore, ifFigure 4 , Figure 5 and Figure 10 As shown in Figure 10 , the fixture mechanism 5 further includes a sleeve 58, a drive rod 59, and a linear motor 50. One end of the control rod 531 of the pusher assembly 53 is connected to one end of the drive rod 59 through the sleeve 58, and the other end of the drive rod 59 is connected to the linear motor 50.

[0094] During actual operation, the linear motor 50 (which can be a 28HS series micro-precision linear stepping motor, equipped with a T-shaped lead screw slide, with an effective stroke of 150 mm) drives the drive rod 59 to work, and the drive rod 59 drives the control rod 531 to work, realizing the electric control of the control rod 531, automatic feeding, and more precise control of the moving position.

[0095] Referring to Figures 1 - 5 As shown in Figures 1 - 5 , the cooling mechanism 1 includes a cooling box 11, a lower pressing plate 12, a first support rod 13, a first elastic member 14, an upper pressing plate 15, a fixing rod 16, and a box cover 17.

[0096] A plurality of second through holes 121 are evenly distributed on the lower pressing plate 12. As Figures 1 - 6 shows a schematic structural diagram of an array of a total of sixteen rectangular second through holes 121 arranged in a four-by-four pattern on the lower pressing plate 12.

[0097] The first support rod 13 includes at least one, and at least one first support rod 13 passes through the lower pressing plate 12 so that the lower pressing plate 12 can slide along the first support rod 13.

[0098] Both the first support rod 13 and the lower pressing plate 12 are arranged inside the cooling box 11. Exemplarily, the lower end of the first support rod 13 is fixedly arranged on the bottom surface of the cooling box 11 so that the first support rod 13 is stably arranged inside the cooling box 11. A nut is fastened to the upper end of the first support rod 13 to prevent the lower pressing plate 12 from slipping out of the upper end of the first support rod 13. The first support rod 13 can be one, two, three, four, etc. in number. As Figures 1 - 3 shows a schematic structural diagram of four first support rods 13. Four first support rods 13 are arranged at the four corners of the lower pressing plate 12. After the four first support rods 13 stand in the cooling box 11, they can provide a binding force in the plane direction for the lower pressing plate 12 and play a guiding role during the sliding process of the lower pressing plate 12.

[0099] The first elastic member 14 is arranged between the lower pressing plate 12 and the bottom surface of the cooling box 11. The first elastic member 14 can provide a longitudinal supporting force for the lower pressing plate 12 and cooperate with the first support rod 13 to support the lower pressing plate 12.

[0100] Optionally, the first elastic member 14 can be a spring. The number of the first elastic members 14 can be the same as the number of the first support rods 13. As Figures 1 - 3The structure diagram shows that the first elastic member 14 is a spring, and there are four springs. The four springs are arranged between the lower pressing plate 12 and the bottom surface of the cooling box 11 and sleeved on the first support rod 13.

[0101] The upper pressing plate 15 is fixedly arranged at the bottom of the fixed rod 16, and the top is fixedly arranged on the box cover 17. Of course, a plurality of third through holes 151 are uniformly distributed on the upper pressing plate 15, so that the first cooling substance can flow from below the upper pressing plate 15 to above the upper pressing plate 15. A third handle 18 is arranged on the box cover 17 to facilitate taking the box cover 17.

[0102] Among them, as Figures 1 - 6 shown, the cooling box 11 of the embodiment of the present application is a hexahedron with an open upper end. Correspondingly, the shapes of the lower pressing plate 12, the upper pressing plate 15 and the box cover 17 are all rectangular. Of course, the shape of the cooling box 11 is adapted to the shape of the prepreg 7. For the convenience of cutting, generally the prepreg 7 is rectangular, so the cooling box 11 is generally arranged as a hexahedron.

[0103] When the cooling mechanism 1 provided by the embodiment of the present application is actually used, the fixture mechanism 5 carrying the prepreg 7 (the handle 55 of the fixture mechanism 5 is set at a sufficient height, but the height is lower than the height of the fixed rod 16. When the fixture mechanism 5 is removed from the cooling mechanism 1 after cooling, it can keep a sufficient distance from the first cooling substance and the cooling mechanism 1 to avoid freezing injury to the operator. The size of the fixture mechanism 5 is smaller than the size of the lower pressing plate 12) is placed on the lower pressing plate 12, and then the box cover 17 is slowly closed on the cooling box 11. The upper pressing plate 15 is fixedly arranged at the bottom of the fixed rod 16, and the top is fixedly arranged on the box cover 17. The upper pressing plate 15 arranged below the closed box cover 17 presses down the fixture mechanism 5. During the process of closing the box cover 17, the upper pressing plate 15 and the lower pressing plate 12 clamp the fixture mechanism 5 and slowly descend until the box cover 17 is closed on the cooling box 11.

[0104] The fixture mechanism 5 is arranged on the lower pressing plate 12 (the size of the fixture mechanism 5 is adapted to the sizes of the cooling box 11 and the lower pressing plate 12, and the distance between the two handles 55 is greater than the width of the upper pressing plate 15). Since the first support rod 13 passes through the lower pressing plate 12, the lower pressing plate 12 can slide along the first support rod 13. The fixture mechanism 5 and the lower pressing plate 12 both move downward and are immersed in the first cooling substance to achieve good cooling, so that the resin contained in the prepreg 7 is transformed into a vitrified state to obtain a cooled prepreg, overcoming the influence of the resin viscosity in the prepreg 7 and solving the problem of low manual sample preparation efficiency in the process of preparing samples of the prepreg 7. At the same time, the setting of the second through hole 121 on the lower pressing plate 12 (the setting of the third through hole 151 on the upper pressing plate 15) enables the first cooling substance to flow from below the lower pressing plate 12 to above the lower pressing plate 12, allowing the first cooling substance to flow into the fixture mechanism 5 to cool the prepreg 7. At the same time, since the first cooling substance timely flows from below the lower pressing plate 12 through the second through hole 121 to above the lower pressing plate 12, during the downward pressing process, the pressure of the first cooling substance on the lower pressing plate 12 can be reduced, enabling the lower pressing plate 12 to be pressed downward and the box cover 17 to be smoothly and quickly closed. At this time, the first elastic body is compressed to accumulate compressive force.

[0105] When it is necessary to take out the fixture mechanism 5 carrying the prepreg 7, the box cover 17 is opened and removed. The fixture mechanism 5 and the lower pressing plate 12 are no longer under pressure, and the first elastic member 14 releases the compressive force. This compressive force causes the fixture mechanism 5 and the lower pressing plate 12 to move slowly upward, away from the first cooling substance, facilitating the removal of the fixture mechanism 5 carrying the prepreg 7.

[0106] When the first cooling substance is a coolant, liquid nitrogen is preferably used, and liquid nitrogen has a better cooling effect on the prepreg 7. When the first cooling substance is a refrigerant, dry ice can be used. Dry ice is solid carbon dioxide, which absorbs a large amount of heat in its surrounding during the sublimation process. The gaseous carbon dioxide formed by the sublimation of dry ice can pass through the second through hole 121 provided on the lower pressing plate 12 of the cooling mechanism 1, the third through hole 151 provided on the upper pressing plate 15, and the first through hole 521 provided in the fixture mechanism 5.

[0107] As Figure 1 and Figure 3 shown, the cutting platform 2 includes a first sub-platform 21 and a second sub-platform 22. The first sub-platform 21 and the second sub-platform 22 are arranged in parallel at intervals, and a cutting opening is formed at the interval. After the cooled prepreg is conveniently placed in the cutting opening, the cutting mechanism 3 cuts the cooled prepreg, and the sampling cup 4 receives the prepreg test sample.

[0108] As Figures 1 - 6As shown, the prepreg sample preparation device further includes a drying mechanism 6. The first sub-platform 21 includes a hexahedron and a placement plate 211. The hexahedron includes a box body and a box door, and the placement plate 211 is inserted in the middle of the hexahedron. The drying mechanism 6 is arranged on the bottom surface of the hexahedron. The drying mechanism 6 can be a condenser, and vacuum freeze-drying mode is adopted for drying to avoid chemical reactions during the drying process. The first sub-platform 21 is arranged between the cooling mechanism 1 and the second sub-platform 22.

[0109] By setting the drying mechanism 6, according to different characterization methods, the prepreg test samples to be dried can be placed in containers such as crucibles, and then placed on the placement plate 211 of the first sub-platform 21 for drying, so as to avoid the increase in the difficulty of re-sampling due to the restoration of the stickiness of the sample particles after returning to room temperature. After drying is completed and the temperature returns to room temperature, the prepreg test samples are taken out to avoid the generation of condensed water. At the same time, by using the first sub-platform 21 to place the drying mechanism 6, the space can be utilized reasonably and effectively.

[0110] As Figure 1 and Figure 2 shown, the cutting mechanism 3 includes a cutting blade 31, a fixing plate 32, a second support rod 33, a second elastic member 34 and a driving assembly 35.

[0111] The top of the cutting blade 31 is fixedly arranged on the fixing plate 32. The second support rod 33 includes at least one, and the lower end of at least one second support rod 33 is arranged on the cutting platform 2 and passes through the fixing plate 32 so that the fixing plate 32 can slide along the second support rod 33. By way of example, the lower end of the second support rod 33 is fixedly arranged on the cutting platform 2 so that the second support rod 33 is stably arranged on the cutting platform 2. A nut is fastened to the upper end of the second support rod 33 to prevent the fixing plate 32 from slipping out of the upper end of the second support rod 33. The second support rod 33 can be one, two, three, four or other numbers. As Figures 1 - 3 shown, the structural schematic diagram of the second support rod 33 being four is shown. Four second support rods 33 are arranged through the four corners of the fixing plate 32. After the four second support rods 33 stand on the cutting platform 2, they can provide a binding force in the plane direction for the fixing plate 32 and play a guiding role during the sliding process of the fixing plate 32.

[0112] The second elastic member 34 is arranged between the cutting platform 2 and the fixing plate 32. The second elastic member 34 can provide a longitudinal supporting force for the fixing plate 32 and cooperate with the second support rod 33 to support the fixing plate 32.

[0113] Optionally, the second elastic member 34 can be a spring. The number of the second elastic members 34 can be the same as the number of the second support rods 33. As Figures 1 - 3 shown, the structural schematic diagram of the second elastic member 34 being a spring and there being four springs is shown. The four springs are arranged between the cutting platform 2 and the fixing plate 32 and sleeved on the second support rods 33.

[0114] The driving component 35 is connected to the fixed plate 32 to drive the fixed plate 32 to move up and down, and further drive the cutting blade 31 to cut the cooled prepreg at the material cutting port.

[0115] When the cutting mechanism 3 provided by the embodiment of the present application is actually used, the cooled prepreg is arranged at the material cutting port of the material cutting platform 2, and the driving component 35 drives the fixed plate 32 to move downward. Since the top of the cutting blade 31 is fixed on the fixed plate 32, at least one second support rod 33 passes through the fixed plate 32, and the fixed plate 32 can slide along the second support rod 33. The lower end of the second support rod 33 abuts against the material cutting platform 2. The downward movement of the fixed plate 32 drives the cutting blade 31 to move downward to cut the cooled prepreg. At this time, the second elastic member 34 is compressed to accumulate compressive force.

[0116] After that, the driving component 35 drives the fixed plate 32 to move upward. At the same time, the second elastic member 34 releases the compressive force, and the fixed plate 32 quickly drives the cutting blade 31 to move upward until the cutting blade 31 is separated from the material cutting platform 2, realizing the zero displacement of the cutting tool. This process is repeated, and with the advancement of the cooled prepreg at its own preset speed, the cooled prepreg can be successively cut according to a fixed width to obtain prepreg test samples, and the obtained prepreg test samples can reach the required particle size.

[0117] Refer to Figures 1 - 3 As shown in the figure, the driving component 35 includes a motor 351, a cam 352, a first connecting rod shaft 353, a first connecting rod 354, a second connecting rod shaft 355 and a hinge seat 356. The cam 352 is sleeved on the output shaft of the motor 351. One end of the first connecting rod shaft 353 is arranged on the cam 352, and the other end is connected to one end of the first connecting rod 354. The second connecting rod shaft 355 passes through the other end of the first connecting rod 354, and both ends are hinged to the hinge seat 356. The hinge seat 356 is fixed on the top surface of the fixed plate 32.

[0118] In practice, when the motor 351 works, it drives the cam 352 to rotate. The first connecting rod shaft 353 connects the cam 352 and the first connecting rod 354. The first connecting rod 354 connects the second connecting rod shaft 355. The second connecting rod shaft 355 is hinged to the hinge seat 356, and the hinge seat 356 is fixed on the top surface of the fixed plate 32. Therefore, when the motor 351 works, it can drive the fixed plate 32 to move up and down, and further drive the cutting blade 31 to perform periodic reciprocating cutting motion up and down. The moving direction of the cutting blade 31 is perpendicular to the material cutting platform 2, and it cooperates with the material cutting platform 2 to jointly provide a shearing force for the cooled prepreg, realizing the cutting of thin-layer and room-temperature viscous materials. By driving the cutting blade 31 with the motor 351, the cooled prepreg can be automatically cut, and the cutting frequency can be controlled. Automatic cutting can obtain finer sample particles, improve the consistency of the fiber-to-resin ratio between samples, improve the sample preparation efficiency and controllability, improve the uniformity of the samples, and improve the sample preparation accuracy.

[0119] It can automatically control the start and stop of the motor 351 to achieve automatic cutting at a certain frequency. It can also be manually controlled to start and stop the motor 351 to achieve manual control of successive cutting.

[0120] Of course, in order to place the motor 351, a support frame 36 can also be set to install the motor 351.

[0121] Furthermore, the cutting mechanism 3 further includes a protective cover 37. The protective cover 37 is a hexahedron and covers the cutting blade 31, the fixing plate 32, the second support rod 33, the second elastic member 34 and part of the driving assembly 35 to protect these components from being damaged. A through port is provided at the position of the protective cover 37 above the first sub-platform 21 to facilitate the input of the cooled prepreg to the lower part of the cutting mechanism 3.

[0122] As Figure 2 shown, the fixture mechanism 5 is adapted to the size of the through port. The open end of the fixture mechanism 5 can partially extend into the protective cover 37. The first handle 55 near the opening is in close contact with the wall plate of the protective cover 37 to prevent the fixture mechanism 5 from moving further along the feeding direction.

[0123] Two limiting bars 212 are arranged in parallel above the first sub-platform 21. The extending direction of the limiting bars 212 is the same as the feeding direction. The width between the two limiting bars 212 is the same as the width of the carrying box 51 of the fixture mechanism 5. Thus, the fixture box body is placed on the first sub-platform 21, and the carrying box 51 is stuck between the two limiting bars 212 to prevent the fixture mechanism 5 from sliding arbitrarily during the cutting process. The first handle 55 at the tail end of the fixture mechanism 5 can be pressed by hand to limit the tilting of the fixture mechanism 5 during the cutting of the cooled prepreg, so that the fixture mechanism 5 remains fixed during the cutting process and meets the usage conditions of the cutting mechanism 3.

[0124] As Figure 11 and Figure 12 shown, the material taking cup 4 includes a cup body 41, a second handle 42 and a stirring assembly 43. The cup body 41 is in the shape of a frustum of a pyramid. The second handle 42 is arranged on the side of the cup body 41. The stirring assembly 43 is configured to stir the inner cavity of the cup body 41.

[0125] During the actual use process, a second cooling substance is injected into the cup body 41 to cool down the cup body 41. The operator holds the second handle 42 and places the material taking cup 4 under the cutting port to collect the prepreg test samples falling from the cutting. The prepreg test samples fall into the second cooling substance in the cup body 41 to avoid the prepreg test samples from warming up.

[0126] When the second cooling substance is a coolant, dry ice is preferably used, which can well prevent the pre-preg test sample from warming up. The second cooling substance can also be a coolant liquid, such as liquid nitrogen. Among them, the first cooling substance and the second cooling substance can use liquid nitrogen simultaneously, or use dry ice simultaneously. It is more convenient to use the same cooling substance for the first cooling substance and the second cooling substance. When both the first cooling substance and the second cooling substance use dry ice simultaneously, a placement basket or placement grid for holding dry ice can be respectively arranged at the bottom of the cooling box 11 and the bottom of the cup body 41 of the material taking cup 4.

[0127] Subsequently, the operator holds the second handle 42 and takes out the cup body 41. Then, the pre-preg test sample is evenly tapped to break the large particles frozen together, so that the particle size of the pre-preg test sample is basically consistent. The inner cavity of the cup body 41 is stirred by the stirring assembly 43 to further improve the consistency of the resin-to-fiber ratio of a single pre-preg test sample and all pre-preg test samples. Finally, the material is poured out. The setting of the second handle 42 facilitates the operator to take and place the material taking cup 4. The inner bottom of the cup body 41 is set as an arc surface to facilitate the stirring operation of the stirrer.

[0128] Optionally, the second sub-platform 22 is in an inverted "U" shape. Thus, it is convenient for the material taking cup 4 to pass through the inner cavity of the second sub-platform 22 and be located below the cutting opening to receive the pre-preg test sample obtained by cutting.

[0129] Furthermore, the two side walls of the cup body 41 adjacent to the side wall where the handle is set are planar, so as to facilitate the material taking cup 4 to pass through the inner cavity of the second sub-platform 22. The other side wall of the material taking cup 4 opposite to the side wall where the handle is set is an inclined surface, which facilitates the pre-preg test sample to slide into the inner cavity of the material taking cup 4 and can also reduce the weight of the material taking cup 4.

[0130] The stirring assembly 43 includes a handle 431, a second connecting rod 432, a main shaft 433 and a turning plate 434. The main shaft 433 is rotatably connected to the opposite two side walls of the cup body 41. There are four turning plates 434, and the four turning plates 434 are arranged in a circular array along the central axis of the main shaft 433 on the outer wall of the main shaft 433 and are located in the inner cavity of the cup body 41. One end of the main shaft 433 passes through the side wall and is connected to one end of the second connecting rod 432, and the other end of the second connecting rod 432 is connected to one end of the handle 431. When it is actually necessary to stir the pre-preg test sample, the handle 431 is rotated, and the handle 431 drives the second connecting rod 432, the main shaft 433 and the turning plate 434 to rotate in sequence, so that the turning plate 434 can stir the pre-preg test sample in the inner cavity of the cup body 41 evenly during the rotation process.

[0131] Such as Figure 1 and Figure 6As shown, the side wall of the second sub-platform 22 is provided with an avoidance groove 221 to facilitate avoiding the second connecting rod 432 during the process of taking and placing the material cup 4, so that the handle 431 is located outside the second sub-platform 22, which is convenient for cutting the cooled prepreg while stirring the prepreg test sample in the material cup 4.

[0132] The bottom of the cup body 41 is provided with at least one groove 44. Figure 1 and Figure 11 The schematic diagram of the structure shows that there are two grooves 44 at the bottom of the cup body 41. The cutting platform 2 also includes a guide plate 23, which is arranged below the second sub-platform 22. A guide rail 24 is arranged on the guide plate 23, which is adapted to the shape and position of the groove 44. The arrangement of the groove 44 and the guide rail 24 can play a guiding and positioning role in the process of taking and placing the material cup 4.

[0133] Another embodiment of the present invention provides a prepreg sample preparation method, based on the above-mentioned prepreg sample preparation device, comprising:

[0134] The prepreg 7 placed in the cooling mechanism 1 is cooled until the resin contained in the prepreg 7 is converted into a vitrified state to obtain a cooled prepreg. The prepreg 7 should be appropriately cut before being placed in the cooling mechanism 1 to facilitate placement in the cooling mechanism 1. For unidirectional prepreg 7, the cutting length direction is consistent with the fiber direction. For fabric prepreg 7, the cutting length direction is consistent with the fiber angle bisector direction, which is convenient for cutting fibers and adjusting the cutting angle during cutting.

[0135] The prepreg 7 can be cooled by a single layer or by cooling after multi-layer laying. The thickness of multi-layer laying shall not exceed 2mm, and the fiber direction between each layer shall remain consistent. The cooling temperature of the cooling mechanism 1 is -196℃~-78℃. When the first cooling substance in the cooling mechanism 1 is a coolant, liquid nitrogen can be used, and when it is a refrigerant, dry ice can be used. After the first cooling substance is completely consumed, the first cooling substance shall be replenished in time before the temperature rises to -20℃. The cooling time for a single-layer prepreg 7 shall not be less than 10s, and shall increase accordingly with the number of laying layers. For a 2mm thick multi-layer prepreg 7, it shall not be less than 1min.

[0136] The cooled prepreg is quickly placed on the cutting platform 2, placed under the cutting mechanism 3, and the cooled prepreg is pressed. Specifically, the fixing member 54 of the clamp mechanism 5 moves upward to release the cooling prepreg, and the fixing member 54 moves to a relative distance from the bottom plate of the carrying box 51 to a state where the cooling prepreg can be pushed out but is not completely loose, and stops moving, thereby ensuring that the cooling prepreg can be pushed out smoothly when being cut, and the cooling prepreg is pressed and will not warp. If the cooling prepreg is transferred by manually taking the cooling prepreg, the cooling prepreg can be pressed manually.

[0137] For the unidirectional prepreg 7, it is placed perpendicular to the cutting direction of the cutting blade 31 in the fiber direction. For the fabric prepreg 7, it is placed perpendicular to the cutting direction of the cutting blade 31 in the direction of the angular bisector of the fiber angle. The cutting blade 31 descends rapidly and fits against the vertical surface of the material cutting mechanism 3, and together they apply a shearing force to the cooled prepreg for cutting. It is possible to cut successively with a fixed-width feed and continuously with a certain feed rate to obtain sample particles of the required particle size. At the same time, by adjusting the fiber direction and cutting width of the prepreg 7, the required particle size of the sample particles can be obtained, achieving the consistency of the sample particle size.

[0138] The cooled prepreg is cut by the material cutting mechanism 3 provided above the material cutting platform 2 to obtain a prepreg test sample. During the cutting process, cooling is carried out by using a third cooling substance (such as dry ice or liquid nitrogen) inside the protective cover to prevent the cooled prepreg from warming up during cutting. Of course, since the material taking cup 4 is arranged below the material cutting platform 2, the second cooling substance placed in the material taking cup 4 can also cool the inner cavity of the protective cover.

[0139] The prepreg test sample is collected by the material taking cup 4 below the material cutting opening of the material cutting platform 2. At this time, the prepreg test sample is scattered fine particles. A second cooling substance is injected into the material taking cup 4 and placed below the material cutting opening to cool the protective cover, and the temperature range is controlled below -20°C to prevent the cooled prepreg from warming up during cutting. The collected prepreg test sample in the material taking cup 4 is tapped and broken up the large particles frozen together to make the particle size basically consistent, and then the prepreg test sample is further stirred evenly.

[0140] Restoring the sample particles directly to room temperature will cause condensed water to condense on the surface. The prepreg test sample is dried by the drying mechanism 6 using a vacuum freeze-drying mode to avoid chemical reactions during the drying process. According to different characterization methods, the sample particles can be placed in a crucible or other containers and then dried to avoid the viscosity of the sample particles from recovering after restoring to room temperature, which increases the difficulty of re-sampling. After drying is completed and restored to room temperature, the sample is taken out to avoid generating condensed water and ensure that the sample performance can fully represent the performance of the prepreg 7. The working temperature of the condenser is -55°C.

[0141] The prepreg test sample prepared by using the prepreg sample preparation device and method of the embodiment of the present application can be used for characterization methods such as infrared analysis (FTIR), differential scanning calorimetry analysis (DSC), thermogravimetric analysis (TGA), etc., and is not limited to the above-mentioned characterization methods. And it can be used to characterize properties such as infrared reflectivity, glass transition temperature, reaction enthalpy change, thermal stability, etc., and is not limited to characterizing the above-mentioned properties.

[0142] A specific embodiment is provided here.

[0143] Sample preparation of a certain carbon fiber / epoxy prepreg 7 by differential scanning calorimetry (DSC).

[0144] A certain carbon fiber / epoxy prepreg 7 includes specifications such as unidirectional prepreg 7 and fabric prepreg 7 (plain weave, satin weave, twill). The mass of the prepreg test sample by differential scanning calorimetry (DSC) is 5 mg to 15 mg, and the accuracy is 0.01 mg. The sample preparation steps are as follows:

[0145] Cut the single-layer prepreg 7 to an area size suitable for placing in the cooling mechanism 1. For the unidirectional prepreg 7, the cutting length direction is kept consistent with the fiber direction to ensure that it can be cut perpendicular to the fiber axis during cutting. For the fabric prepreg 7, the cutting length direction is kept consistent with the bisector direction of the fiber angle to ensure that the cutting angles of the carbon fiber warp and weft are the same during cutting. Since the sample consumption for differential scanning calorimetry (DSC) sample preparation is extremely small, a single-layer prepreg 7 is used.

[0146] Inject liquid nitrogen into the cooling box 11 in advance, with a cooling temperature of -196 °C, and use the fixture mechanism 5 to carry the prepreg 7. Then immerse the fixture mechanism 5 carrying the prepreg 7 into the cooling mechanism 1 for cooling until the resin contained in the prepreg 7 is transformed into a vitrified state to obtain a cooled prepreg. The cooling time is not less than 10 s. After the liquid nitrogen is completely consumed, replenish the liquid nitrogen in time before the temperature rises to -20 °C.

[0147] Then quickly place the cooled prepreg on the cutting platform 2 and place it under the cutting mechanism 3. And tighten it firmly on the cutting platform 2.

[0148] For the unidirectional prepreg 7, place it perpendicular to the cutting direction of the cutting blade 31 in the fiber direction. For the fabric prepreg 7, place it perpendicular to the cutting direction of the cutting blade 31 in the bisector direction of the fiber angle. The cutting blade 31 descends rapidly and fits with the vertical surface of the cutting mechanism 3 to jointly apply a shearing force to the cooled prepreg for cutting. It can be cut successively by feeding at a fixed width and continuously by feeding at a certain rate to obtain sample particles of the required particle size. At the same time, by adjusting the fiber direction and cutting width of the prepreg 7, the required particle size of the sample particles can be obtained to achieve the consistency of the sample particle size.

[0149] The cooled prepreg is cut by the cutting mechanism 3 arranged above the cutting platform 2 to obtain a prepreg test sample. During the cutting process, dry ice is used for cooling inside the protective cover to prevent the cooled prepreg from warming up during cutting.

[0150] The prepreg test sample is collected by the sampling cup 4 below the cutting opening of the cutting platform 2. At this time, the prepreg test sample is scattered fine particles. Dry ice is injected into the sampling cup 4 and placed below the cutting opening to cool the protective cover, and the temperature range is controlled below -20°C to avoid the temperature rise of the cooled prepreg during cutting. The collected prepreg test sample in the sampling cup 4 is knocked and broken to break the large particles frozen together, so that the particle sizes are basically the same, and then the prepreg test sample is further stirred evenly.

[0151] The prepreg test sample is dried by the drying mechanism 6 in a vacuum freeze-drying mode to avoid chemical reactions during drying. According to the sample preparation method of DSC, the solid crucible (including the lid) is weighed, and the prepreg test sample to be dried is put into the solid crucible (including the lid) and weighed again. The difference is about 10 mg. After removing the lid of the solid crucible, it is placed in the first sub-platform 21 for drying, and the drying time is not less than 4 h. After drying is completed and the temperature returns to room temperature, the crucible containing the sample particles is taken out to avoid generating condensed water. The crucible and the lid containing the sample particles are weighed again, and the difference from the weighing of the empty solid crucible (including the lid) is used as the weight of the dried sample particles for the enthalpy change analysis of differential scanning calorimetry (DSC). The working temperature of the condenser is -55°C. If multiple groups of samples are needed, they can be dried centrally.

[0152] The various embodiments in this specification are described in a progressive manner. For the same or similar parts between the various embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments.

[0153] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting the present application; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the present application.

Claims

1. A prepreg sample preparation device, characterized in that: It includes a cooling mechanism, a cutting platform, a cutting mechanism and a material taking cup; The cooling mechanism is configured to cool the prepreg placed therein until the resin contained in the prepreg is converted into a vitrified state to obtain a cooled prepreg; The cutting platform is configured to place the cooled prepreg; The cutting mechanism is disposed above the cutting platform and is configured to cut the cooled prepreg to obtain a prepreg test sample; The material taking cup is arranged below the cutting opening of the cutting platform and is configured to receive the prepreg test sample.

2. The prepreg sample preparation device according to claim 1, characterized in that: Also included is a clamp mechanism; The clamp mechanism is configured to hold the prepreg and then place it in the cooling mechanism for cooling to obtain the cooled prepreg, and then transfer the cooled prepreg to the cutting platform and advance it at a preset speed for cutting.

3. The prepreg sample preparation device according to claim 2, characterized in that: The clamp mechanism includes a carrying box, a partition plate, a material pushing assembly, a fixing member and a handle; The carrying box is a hexahedron, and at least one side thereof is provided with an opening; The partition plate is clamped in the middle of the carrying box, and a through slot is provided in the middle, and the extending direction of the through slot is perpendicular to the opening; A window is provided on at least one side of the carrying box which is parallel to the extending direction of the through slot and is located above the partition plate; The top plate and bottom plate of the carrying box and the partition plate are all provided with a plurality of first through holes; The pusher assembly comprises a control rod, a connecting rod and a pusher rod; The control rod and the push rod are respectively fixed at both ends of the connecting rod, and the control rod and the push rod are parallel; The pusher assembly is arranged in the carrying box; the control rod is located above the partition plate, and at least one end thereof extends out of the window of the carrying box; the pusher rod is arranged below the partition plate; the connecting rod is clamped in the through slot and can move along the through slot; The fixing member is inserted into one end of the through slot close to the opening; The handle comprises at least one, and the at least one handle is arranged on the top surface of the carrying box.

4. The prepreg sample preparation device according to claim 1, characterized in that: The cooling mechanism comprises a cooling box, a lower pressing plate, a first supporting rod, a first elastic member, an upper pressing plate, a fixing rod and a box cover; A plurality of second via holes are evenly distributed on the lower pressing plate; The first support rod comprises at least one first support rod, and the at least one first support rod is penetrated through the lower pressing plate, so that the lower pressing plate can slide along the first support rod; The first support rod and the lower pressing plate are both arranged in the cooling box; The first elastic member is arranged between the lower pressing plate and the bottom surface of the cooling box; The upper pressing plate is fixedly arranged at the bottom of the fixing rod, and the top of the fixing rod is fixedly arranged at the box cover.

5. The prepreg sample preparation device according to claim 1, characterized in that: The cutting platform includes a first sub-platform and a second sub-platform; The first sub-platform and the second sub-platform are arranged in parallel and spaced apart, and a cutting opening is formed at the spaced apart position.

6. The prepreg sample preparation device according to claim 5, characterized in that: Also includes a drying mechanism; The first sub-platform includes a hexahedron and a placement plate; The placement plate is inserted in the middle of the hexahedron; The drying mechanism is arranged on the bottom surface of the hexahedron.

7. The prepreg sample preparation device according to claim 1, characterized in that: The cutting mechanism comprises a cutting blade, a fixing plate, a second supporting rod, a second elastic member and a driving assembly; The top of the cutting blade is fixed to the fixing plate; The second support rod comprises at least one, the lower end of the at least one second support rod is arranged on the cutting platform and penetrates the fixing plate so that the fixing plate can slide along the second support rod; The second elastic member is arranged between the cutting platform and the fixing plate; The driving assembly is connected to the fixing plate to drive the fixing plate to move up and down, thereby driving the cutting blade to cut the cooling prepreg at the cutting opening.

8. The prepreg sample preparation device according to claim 7, characterized in that: The driving assembly includes a motor, a cam, a first connecting rod shaft, a first connecting rod, a second connecting rod shaft and an articulated seat; The cam is sleeved on the output shaft of the motor; One end of the first connecting rod shaft is arranged on the cam, and the other end is connected to one end of the first connecting rod; The second connecting rod shaft is passed through the other end of the first connecting rod, and both ends are hinged to the hinge seat; The hinge seat is fixed on the top surface of the fixing plate.

9. The prepreg sample preparation device according to claim 1, characterized in that: The material taking cup comprises a cup body, a second handle and a stirring assembly; The cup body is in the shape of a quadrangular pyramid; The second handle is arranged on the side of the cup body; The stirring component is configured to stir the inner cavity of the cup body.

10. A method for preparing a prepreg sample, characterized in that: The prepreg sample preparation device according to any one of claims 1 to 9 comprises: Cooling the prepreg placed in the cooling mechanism until the resin contained in the prepreg is converted into a glass state to obtain a cooled prepreg; Placing the cooled prepreg on the cutting platform; Cutting the cooled prepreg by a cutting mechanism disposed above the cutting platform to obtain a prepreg test sample; The prepreg test sample is received by the material taking cup below the cutting opening of the cutting platform.

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