A heat-conducting wave-absorbing composite film material preparation device and a preparation method thereof

Abstract

The application provides a heat-conducting wave-absorbing composite film material preparation device and a preparation method thereof, and belongs to the field of composite functional material manufacturing. The heat-conducting wave-absorbing composite film material preparation device comprises a first unwinding unit and a second unwinding unit, a base, a film material conveying unit, a first calendering unit, a stripping unit, a third unwinding unit, a second calendering unit and a heating and curing unit. The first unwinding unit and the second unwinding unit are respectively used for providing an upper film and a bottom film; the first calendering unit is used for performing first calendering on the upper film, the bottom film and the heat-conducting phase change material in a molten state on a calendering platform; the stripping unit is configured to be able to strip the upper film after the first calendering; the third unwinding unit is used for providing a new upper film; and the second calendering unit is used for performing second calendering on the bottom film, the new upper film and the heat-conducting phase change material film and the wave-absorbing material together on the calendering platform. The heat-conducting wave-absorbing composite film material preparation device can improve the performance of the prepared heat-conducting wave-absorbing composite film material to a certain extent.

Description

Technical Field

[0001] This application relates to the field of composite functional material manufacturing, and more specifically, to a thermally conductive and microwave-absorbing composite film preparation device and its preparation method. Background Technology

[0002] Thermally conductive and microwave-absorbing composite membranes combine thermal conductivity and microwave absorption functions, and also provide insulation, sealing, shock absorption, and aesthetics. Their corresponding products (such as thermally conductive and microwave-absorbing composite membranes) are widely used in fields such as chip heat dissipation modules, optoelectronic modules, 5G communications, and automotive electronic modules.

[0003] Currently, the main method for preparing thermally conductive and microwave-absorbing composite membranes involves pre-forming thermally conductive and microwave-absorbing membranes separately, and then manually stacking the two membranes together with the help of auxiliary agents (such as adhesives). In this process, the performance of the resulting thermally conductive and microwave-absorbing composite membrane is affected because the two membranes are formed before being stacked together. In addition, this step-by-step preparation method involves many procedures and requires a lot of human intervention, resulting in low production efficiency and poor product quality. Summary of the Invention

[0004] The purpose of this application is to provide a device and method for preparing a thermally conductive and microwave-absorbing composite membrane, which can improve the performance of the prepared thermally conductive and microwave-absorbing composite membrane to a certain extent, while also improving production efficiency and product quality to a certain extent.

[0005] The embodiments of this application are implemented as follows:

[0006] In a first aspect, embodiments of this application provide a thermally conductive and microwave-absorbing composite membrane preparation apparatus, including a first unwinding unit and a second unwinding unit, a base, a membrane material conveying unit, a first calendering unit, a peeling unit, a third unwinding unit, a second calendering unit, and a heat curing unit. The first unwinding unit and the second unwinding unit are respectively used to provide an upper membrane and a bottom membrane; a calendering platform for carrying the membrane material is provided on the top of the base; the membrane material conveying unit is installed on the base to transport the membrane material carried on the calendering platform along the conveying direction; along the conveying direction of the membrane material, the first calendering unit is located downstream of the first unwinding unit and the second unwinding unit, and is used to perform a first calendering of the upper membrane, the bottom membrane, and the molten thermally conductive phase change material between the upper membrane and the bottom membrane on the calendering platform; along the conveying direction of the membrane material, the peeling unit is located downstream of the first calendering unit, and the peeling unit is configured as follows: It can peel off the upper film after the first calendering; along the film material conveying direction, the third unwinding unit is located downstream of the peeling unit and is used to provide a new upper film; along the film material conveying direction, the second calendering unit is located downstream of the third unwinding unit and is used to perform a second calendering on the bottom film, the new upper film, and the thermally conductive phase change material film and the microwave absorbing material between the new upper film and the bottom film on the calendering platform; along the film material conveying direction, the heat curing unit is located downstream of the third unwinding unit and is used to heat and cure the thermally conductive phase change material film and the microwave absorbing material film after the second calendering.

[0007] In the above technical solution, with the cooperation of the first unwinding unit, the second unwinding unit, the film material conveying unit, and the first calendering unit, the thermally conductive phase change material can be calendered to form a thermally conductive phase change material film. Then, the upper film after the first calendering is peeled off by the peeling unit. With the help of the new upper film provided by the third unwinding unit, and with the cooperation of the film material conveying unit and the second calendering unit, the microwave absorbing material can be calendered to form a microwave absorbing material film. Finally, the thermally conductive and microwave absorbing composite film can be obtained through the heating and curing action of the heating and curing unit. With the thermally conductive and microwave absorbing composite film preparation apparatus provided in this application embodiment, the process of preparing the thermally conductive and microwave absorbing composite film can be carried out without the need to prepare the thermally conductive phase change material film and the microwave absorbing material film in steps in advance, and without the need for the artificial superposition of the two film materials with the help of auxiliary agents. This can improve the performance of the prepared thermally conductive and microwave absorbing composite film to a certain extent, and at the same time, it can also improve production efficiency and product quality to a certain extent.

[0008] In some alternative implementations, the first calendering unit includes a first mounting bracket and a first calendering roll. The first mounting bracket is mounted on a base, the first calendering roll is rotatably connected to the first mounting bracket, and the first calendering roll is located above the calendering platform and has a calendering gap. The first unwinding roll in the first unwinding unit is rotatably connected to the first mounting bracket.

[0009] In the above technical solution, the first calendering unit is set up in the form of a first mounting bracket and a first calendering roll cooperating with each other, which has the advantage of a relatively simple structure. On this basis, the first unwinding roll in the first unwinding unit is also mounted on the first mounting bracket, which can reduce the number of mounting brackets and improve the space utilization of the first mounting bracket.

[0010] In some alternative embodiments, the first unwinding unit further includes a first transition roll rotatably connected to a first mounting bracket, the first transition roll being located between the first unwinding roll and the first calendering roll, and the first transition roll being configured to cause the upper film upstream of the first calendering roll to tend to move away from the first calendering roll.

[0011] In the above technical solution, the first unwinding unit is equipped with a first transition roller, and the first transition roller is configured to make the upper film located upstream of the first calendering roller tend to move away from the first calendering roller, so that the upper film is in a straightened state before calendering, thereby helping to improve the calendering effect of the film material; in addition, the first transition roller is configured to be rotatable, which can reduce the friction between the contact surface of the first transition roller and the upper film, thereby better protecting the upper film.

[0012] In some alternative embodiments, the thermally conductive and microwave-absorbing composite membrane preparation apparatus further includes a heating unit located upstream of the first calendering unit along the membrane conveying direction and used to heat and melt the thermally conductive phase change material.

[0013] In the above technical solution, a heating unit is added upstream of the first calendering unit to the thermally conductive and microwave-absorbing composite film preparation device. This unit is used to heat and melt the thermally conductive phase change material before the first calendering, so that the thermally conductive phase change material does not need to be heated and melted in other heating containers before the first calendering, thereby improving the operability and production efficiency of the thermally conductive and microwave-absorbing composite film preparation device.

[0014] In some alternative implementations, the peeling unit includes a peeling roller and a take-up roller. The peeling roller is mounted on top of the base and configured to peel the upper film after the first calendering. The take-up roller is rotatably connected to a first mounting bracket and configured to take up the peeled upper film.

[0015] In the above technical solution, the peeling unit includes a peeling roller and a take-up roller. Through their cooperation, the upper film can be collected in the form of a roll in a timely manner after it is peeled off, which has the advantages of high peeling efficiency and simple overall structure. In addition, installing the take-up roller on the first mounting bracket can reduce the number of mounting brackets and further improve the space utilization of the first mounting bracket.

[0016] In some alternative embodiments, the thermally conductive and microwave-absorbing composite membrane preparation apparatus further includes an auxiliary peeling unit located downstream of the peeling roller along the membrane conveying direction, mounted on top of the base, and configured to separate the partially peeled upper membrane from the end of the thermally conductive phase change material membrane in contact.

[0017] In the above technical solution, the thermally conductive and microwave-absorbing composite film preparation device adds an auxiliary peeling unit downstream of the peeling roller, and sets the auxiliary peeling unit to separate the end of the partially peeled upper film and the thermally conductive phase change material film that are in contact, which makes it easier and faster to separate the upper film and the thermally conductive phase change material film, thereby further improving the efficiency of peeling the upper film.

[0018] In some alternative implementations, the auxiliary stripping unit includes a second mounting bracket and a stripping plate, the second mounting bracket being connected to the top of the base, the stripping plate being connected to the second mounting bracket, and the stripping plate being configured to separate the partially stripped upper film from the end in contact with the thermally conductive phase change material film.

[0019] Optionally, the peeling plate includes a peeling section near the peeling roller and a mounting section away from the peeling roller. The mounting section is connected to a second mounting bracket. The thickness of the peeling section gradually decreases from the end away from the peeling roller to the end near the peeling roller, so that the ends of the partially peeled upper film and the thermally conductive phase change material film in contact can be separated.

[0020] In the above technical solution, the auxiliary stripping unit is set up in the form of a second mounting bracket and a stripping plate, which has the advantage of a relatively simple structure.

[0021] Furthermore, by setting the peeling plate in a form where the mounting section and the peeling section complement each other, the mounting area and the peeling area of ​​the peeling plate can be far apart, so as to reduce interference with the upper film during the peeling process and thus better protect the upper film. In addition, setting the thickness of the peeling section to gradually decrease from the end away from the peeling roller to the end closer to the peeling roller makes it easier to separate the upper film and the thermally conductive phase change material film.

[0022] In some alternative embodiments, the lower surface of the peeling plate is parallel to the table surface of the calendering platform, and the angle α between the side surface of the peeling section away from the calendering platform and the table surface of the calendering platform is 15 to 25°.

[0023] In the above technical solution, the angle α between the surface of the peeling section away from the calendering platform and the table surface of the calendering platform is limited to a specific range, so that the side of the peeling section close to the peeling roller has a suitable inclination, which helps to improve the convenience and efficiency of the peeling section in peeling the upper film.

[0024] In some alternative embodiments, the second calendering unit includes a third mounting bracket and a second calendering roll, the third mounting bracket being mounted on a base, the second calendering roll being rotatably connected to the third mounting bracket, and the second calendering roll being located above the calendering platform and having a calendering gap, and the third unwinding roll in the third unwinding unit being rotatably connected to the third mounting bracket.

[0025] Optionally, the third unwinding unit further includes a second transition roll, which is rotatably connected to the third mounting bracket. The second transition roll is located between the third unwinding roll and the second calendering roll, and is configured to cause the new film upstream of the second calendering roll to tend to move away from the second calendering roll.

[0026] In the above technical solution, the second calendering unit is set up in the form of the third mounting bracket and the second calendering roll cooperating with each other, which has the advantage of relatively simple structure. On this basis, the third unwinding roll in the third unwinding unit is also installed on the third mounting bracket, which can reduce the number of mounting brackets and improve the space utilization of the third mounting bracket.

[0027] Furthermore, the third unwinding unit adds a second transition roller, and the second transition roller is configured to make the new upper film located upstream of the second calendering roller tend to move away from the second calendering roller, so that the new upper film is in a straight state before calendering, thereby helping to improve the calendering effect of the film material; in addition, the second transition roller is configured to be rotatable, which can reduce the friction between the contact surface of the second transition roller and the new upper film, thereby better protecting the new upper film.

[0028] Secondly, embodiments of this application provide a method for preparing a thermally conductive and microwave-absorbing composite film, which is prepared using the thermally conductive and microwave-absorbing composite film preparation apparatus provided in the first aspect embodiment, and includes the following steps:

[0029] The system drives a first unwinding unit and a second unwinding unit to provide an upper film and a bottom film; applies molten thermally conductive phase change material onto the bottom film and drives a film conveying unit so that the upper film, bottom film, and thermally conductive phase change material all undergo a first calendering process in a first calendering unit to obtain a film intermediate; drives a peeling unit to peel off the upper film after the first calendering process to obtain a film precursor; drives a third unwinding unit to provide a new upper film; applies microwave absorbing material onto the film precursor and drives a film conveying unit so that the new upper film and the film precursor carrying the microwave absorbing material both undergo a second calendering process in a second calendering unit; and drives a film conveying unit so that the film precursor after the second calendering process enters a heating and curing unit for curing and shaping.

[0030] In the above technical solution, the thermally conductive and microwave-absorbing composite membrane material preparation device provided in the first aspect embodiment is used to prepare the thermally conductive and microwave-absorbing composite membrane material according to the above process. This eliminates the need to prepare the thermally conductive phase change material membrane and the microwave-absorbing material membrane in steps in advance, and also eliminates the need for the artificial superposition of the two membrane materials with the help of auxiliary agents. This can improve the performance of the prepared thermally conductive and microwave-absorbing composite membrane material to a certain extent, and at the same time, it can also improve the production efficiency and the quality of the prepared product to a certain extent. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the structure of a thermally conductive and microwave-absorbing composite membrane preparation device provided in an embodiment of this application, viewed from a first perspective.

[0033] Figure 2 This is a schematic diagram of the structure of a thermally conductive and microwave-absorbing composite membrane preparation device provided in an embodiment of this application from a second perspective.

[0034] Figure 3 for Figure 1 A magnified view of a section at point A in the middle;

[0035] Figure 4 for Figure 2 A magnified view of a section at point B in the middle;

[0036] Figure 5 This is a schematic diagram of the structure of a peeling plate from a second perspective, provided in an embodiment of this application.

[0037] Figure 6 for Figure 2 A magnified view of a section at point C.

[0038] Icons: 1- Thermally conductive and microwave-absorbing composite membrane preparation device; 10- First unwinding unit; 11- Upper film; 12- First unwinding roller; 13- First transition roller; 20- Second unwinding unit; 21- Bottom film; 30- Base; 31- Calendering platform; 32- Thermally conductive phase change material; 33- Microwave-absorbing material; 40- First calendering unit; 41- First mounting bracket; 42- First calendering roller; 50- Peeling unit; 51- Peeling roller; 52- Rewinding roller; 60- Third unwinding unit; 61- New upper film; 62- Third unwinding roller; 63- Second transition roller; 70- Second calendering unit; 71- Third mounting bracket; 72- Second calendering roller; 80- Heating and curing unit; 90- Auxiliary peeling unit; 91- Second mounting bracket; 92- Peeling plate; 921- Mounting section; 922- Peeling section; a- Membrane material conveying direction. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0041] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0042] In the description of this application, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0043] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0044] The following provides a detailed description of the apparatus and method for preparing a thermally conductive and microwave-absorbing composite membrane material provided in this application.

[0045] See Figure 1 and Figure 2 In a first aspect, embodiments of this application provide a thermally conductive and microwave-absorbing composite film preparation apparatus 1, including a first unwinding unit 10 and a second unwinding unit 20, a base 30, a film conveying unit (not shown in the figure), a first calendering unit 40, a peeling unit 50, a third unwinding unit 60, a second calendering unit 70, and a heating and curing unit 80. The first unwinding unit 10 and the second unwinding unit 20 are respectively used to provide the upper film 11 and the bottom film 21; the top of the base 30 is provided with a calendering platform 31 for carrying the film material; the film material conveying unit is installed on the base 30 so that the film material carried on the calendering platform 31 is transported along the conveying direction; along the conveying direction a of the film material, the first calendering unit 40 is located downstream of the first unwinding unit 10 and the second unwinding unit 20, and is used to perform the first calendering of the upper film 11, the bottom film 21 and the molten thermally conductive phase change material 32 between the upper film 11 and the bottom film 21 on the calendering platform 31; along the conveying direction a of the film material, the peeling unit 50 is located downstream of the first calendering unit 40, and the peeling unit 50 The system is configured to peel off the upper film 11 after the first calendering; along the film conveying direction a, the third unwinding unit 60 is located downstream of the peeling unit 50 and is used to provide a new upper film 61; along the film conveying direction a, the second calendering unit 70 is located downstream of the third unwinding unit 60 and is used to perform a second calendering on the bottom film 21, the new upper film 61, and the thermally conductive phase change material film and the microwave absorbing material 33 between the new upper film 61 and the bottom film 21 on the calendering platform 31; along the film conveying direction a, the heat curing unit 80 is located downstream of the third unwinding unit 60 and is used to heat and cure the thermally conductive phase change material 32 film and the microwave absorbing material film after the second calendering.

[0046] It should be noted that the thermally conductive phase change material film is formed by the first calendering of the molten thermally conductive phase change material 32, and the microwave absorbing material film is formed by the second calendering of the microwave absorbing material 33.

[0047] In this application, with the cooperation of the first unwinding unit 10, the second unwinding unit 20, the film material conveying unit, and the first calendering unit 40, the thermally conductive phase change material 32 can be calendered to form a thermally conductive phase change material film. Then, the upper film 11 after the first calendering is peeled off by the peeling unit 50. With the help of the new upper film 61 provided by the third unwinding unit 60, the microwave absorbing material 33 can be calendered to form a microwave absorbing material film with the cooperation of the film material conveying unit and the second calendering unit 70. Finally, the thermally conductive and microwave absorbing composite film can be obtained by the heating and curing action of the heating and curing unit 80. With the thermally conductive and microwave absorbing composite film preparation apparatus 1 provided in this application embodiment, the process of preparing the thermally conductive and microwave absorbing composite film can be carried out without the need to prepare the thermally conductive phase change material film and the microwave absorbing material film in steps in advance, and without the need for the artificial superposition of the two film materials with the help of auxiliary agents. This can improve the performance of the prepared thermally conductive and microwave absorbing composite film to a certain extent, and at the same time, it can also improve the production efficiency and the quality of the prepared product to a certain extent.

[0048] It should be noted that the specific composition of the thermally conductive phase change material 32 is not limited and can be set in accordance with conventional choices in the art, such as including ceramic powder and binder.

[0049] It should be noted that the melting temperature of the thermally conductive phase change material 32 is mainly determined by the binder therein, and the type of binder is not limited. For example, it can be at least one of fatty acids (melting temperature of 65-80℃), polyethylene glycol (melting temperature of 20-70℃), and crystalline wax (melting temperature of 47-64℃).

[0050] It should be noted that in this embodiment, the thermally conductive phase change material 32 first forms a thermally conductive phase change material film at the first calendering unit 40, and then can be calendered a second time at the second calendering unit 70. This design can further improve the thickness accuracy of the thermally conductive phase change material film.

[0051] It should be noted that the materials of the upper film 11, the bottom film 21, and the new upper film 61 are not limited; for example, all three can be PET release films.

[0052] It should be noted that the form of the membrane material conveying unit is not limited and can be set according to the conventional choices in the field. For example, the membrane material conveying unit can be a combination of guide rollers and conveyor belt drive.

[0053] It is understood that the form of the first rolling unit 40 and the second rolling unit 70 is not limited, and can be set according to conventional choices in the art.

[0054] See Figure 3As an example, the first calendering unit 40 includes a first mounting bracket 41 and a first calendering roll 42. The first mounting bracket 41 is mounted on the base 30. The first calendering roll 42 is rotatably connected to the first mounting bracket 41 and is located above the calendering platform 31 and has a calendering gap. The first unwinding roll 12 in the first unwinding unit 10 is rotatably connected to the first mounting bracket 41.

[0055] In this embodiment, the first calendering unit 40 is configured to cooperate with the first mounting bracket 41 and the first calendering roll 42, which has the advantage of a relatively simple structure. On this basis, the first unwinding roll 12 in the first unwinding unit 10 is also mounted on the first mounting bracket 41, which can reduce the number of mounting brackets and improve the space utilization of the first mounting bracket 41.

[0056] It is understood that in order to drive the first calendering roll 42 to rotate, the first calendering unit 40 also includes a driving component (e.g., a motor). The power output end of the driving component is connected to the first calendering roll 42 in a transmission connection. In this application, the form of the driving component and the specific installation method are not limited.

[0057] It is understandable that the thermally conductive phase change material 32 is in a molten state during the first calendering process. In order to ensure the effect of the first calendering film formation, it is necessary to maintain the state of the thermally conductive phase change material 32. Based on this, the structure of the first calendering unit 40 can be adjusted.

[0058] As an example, the first calendering unit 40 also includes a heating assembly connected to the first calendering roll 42 for heating and heat preservation of the first calendering roll 42.

[0059] It is understandable that the degree of straightening of the upper film 11 is related to the calendering effect of the film material. Considering the calendering effect of the film material, the structure of the first unwinding unit 10 can be optimized.

[0060] See Figure 3 As an example, the first unwinding unit 10 also includes a first transition roller 13, which is rotatably connected to the first mounting bracket 41. The first transition roller 13 is located between the first unwinding roller 12 and the first calendering roller 42, and is configured to cause the upper film 11 upstream of the first calendering roller 42 to tend to move away from the first calendering roller 42.

[0061] In this embodiment, the first unwinding unit 10 is provided with a first transition roller 13, and the first transition roller 13 is configured to make the upper film 11 located upstream of the first calendering roller 42 tend to move away from the first calendering roller 42, so that the upper film 11 is in a straightened state before calendering, thereby helping to improve the calendering effect of the film material; in addition, the first transition roller 13 is configured to be rotatable, which can reduce the friction between the contact surface of the first transition roller 13 and the upper film 11, thereby better protecting the upper film 11.

[0062] It should be noted that the form of the second unwinding unit 20 is not limited, as long as it can transport the bottom film 21 to the calendering platform 31.

[0063] It is understandable that the method of heating and melting the thermally conductive phase change material 32 is not limited. For example, it can be heated and melted and then applied to the bottom film 21 of the calendering platform 31, or it can be applied to the bottom film 21 of the calendering platform 31 and then heated and melted.

[0064] As an example, the thermally conductive and microwave-absorbing composite membrane preparation apparatus 1 also includes a heating unit (not shown in the figure), which is located upstream of the first calendering unit 40 along the conveying direction a of the membrane and is used to heat and melt the thermally conductive phase change material 32.

[0065] In this embodiment, a heating unit is added upstream of the first calendering unit 40 to heat and melt the thermally conductive phase change material 32 before the first calendering, so that the thermally conductive phase change material 32 does not need to be heated and melted in other heating containers before the first calendering, thereby improving the operability and production efficiency of the thermally conductive phase change material preparation device 1.

[0066] It is understandable that the form of the heating unit is not limited, as long as it can heat the molten thermally conductive phase change material 32.

[0067] As an example, in the conveying direction a of the film material, a cavity is provided in the calendering platform 31 located upstream of the first calendering unit 40, and a heating unit (e.g., a heating resistance wire) is installed in the cavity to heat the calendering platform 31 in this area, thereby heating and melting the thermally conductive phase change material 32.

[0068] See Figure 4 As an example, the peeling unit 50 includes a peeling roller 51 and a take-up roller 52. The peeling roller 51 is mounted on top of the base 30 and configured to peel the upper film 11 after the first calendering. The take-up roller 52 is rotatably connected to the first mounting bracket 41 and is configured to take up the peeled upper film 11.

[0069] In this embodiment, the peeling unit 50 includes a peeling roller 51 and a take-up roller 52. Through their cooperation, the upper film 11 can be collected in the form of a roll in a timely manner after it is peeled off, which has the advantages of high peeling efficiency and simple overall structure. In addition, by mounting the take-up roller 52 on the first mounting bracket 41, the number of mounting brackets can be reduced, and the space utilization of the first mounting bracket 41 can be further improved.

[0070] Understandably, in order to further improve the peeling efficiency of the upper film 11, the structure of the thermally conductive and microwave-absorbing composite film preparation device 1 can be optimized.

[0071] See Figure 4 As an example, the thermally conductive and microwave-absorbing composite membrane preparation apparatus 1 also includes an auxiliary peeling unit 90. Along the conveying direction a of the membrane, the auxiliary peeling unit 90 is located downstream of the peeling roller 51. The auxiliary peeling unit 90 is mounted on the top of the base 30 and is configured to separate the partially peeled upper membrane 11 from the end of the thermally conductive phase change material 32 membrane in contact.

[0072] In this embodiment, the thermally conductive and microwave-absorbing composite film preparation apparatus 1 adds an auxiliary peeling unit 90 downstream of the peeling roller 51, and sets the auxiliary peeling unit 90 to separate the end of the partially peeled upper film 11 and the thermally conductive phase change material film that are in contact, so that the upper film 11 and the thermally conductive phase change material film can be separated more easily and quickly, thereby further improving the efficiency of peeling the upper film 11.

[0073] As an example, the auxiliary peeling unit 90 includes a second mounting bracket 91 and a peeling plate 92. The second mounting bracket 91 is connected to the top of the base 30, and the peeling plate 92 is connected to the second mounting bracket 91. The peeling plate 92 is configured to separate the partially peeled upper film 11 from the end in contact with the thermally conductive phase change material film.

[0074] In this embodiment, the auxiliary peeling unit 90 is configured to cooperate with the second mounting bracket 91 and the peeling plate 92, which has the advantage of a relatively simple structure.

[0075] See Figure 5 As an example, the peeling plate 92 includes a peeling section 922 on the side near the peeling roller 51 and a mounting section 921 on the side away from the peeling roller 51. The mounting section 921 is connected to the second mounting bracket 91. The thickness of the peeling section 922 gradually decreases from the end away from the peeling roller 51 to the end near the peeling roller 51 so that the partially peeled upper film 11 and the end in contact with the thermally conductive phase change material film can be separated.

[0076] In this embodiment, the peeling plate 92 is configured such that the mounting section 921 and the peeling section 922 cooperate, which allows the mounting area and the peeling area of ​​the peeling plate 92 to be far apart, so as to reduce interference with the upper film 11 during the peeling process and thus better protect the upper film 11. In addition, the thickness of the peeling section 922 is configured to gradually decrease from the end away from the peeling roller 51 to the end closer to the peeling roller 51, which makes it easier to separate the upper film 11 and the thermally conductive phase change material film.

[0077] As an example, the lower surface of the peeling plate 92 is parallel to the table surface of the calendering platform 31, and the angle α between the side surface of the peeling section 922 away from the calendering platform 31 and the table surface of the calendering platform 31 is 15 to 25°, for example, but not limited to any one of 15°, 20° and 25° or any range between two.

[0078] In this embodiment, the angle α between the surface of the peeling section 922 away from the calendering platform 31 and the table surface of the calendering platform 31 is limited to a specific range, so that the side of the peeling section 922 close to the peeling roller 51 has a suitable inclination, which helps to improve the convenience and efficiency of peeling the upper film 11 by the peeling section 922.

[0079] See Figure 6 As an example, the second calendering unit 70 includes a third mounting bracket 71 and a second calendering roll 72. The third mounting bracket 71 is mounted on the base 30, and the second calendering roll 72 is rotatably connected to the third mounting bracket 71. The second calendering roll 72 is located above the calendering platform 31 and has a calendering gap. The third unwinding roll 62 in the third unwinding unit 60 is rotatably connected to the third mounting bracket 71.

[0080] In this embodiment, the second calendering unit 70 is configured to cooperate with the third mounting bracket 71 and the second calendering roll 72, which has the advantage of a relatively simple structure. On this basis, the third unwinding roll 62 in the third unwinding unit 60 is also mounted on the third mounting bracket 71, which can reduce the number of mounting brackets and improve the space utilization of the third mounting bracket 71.

[0081] See Figure 6 As an example, the third unwinding unit 60 also includes a second transition roller 63, which is rotatably connected to the third mounting bracket 71. The second transition roller 63 is located between the third unwinding roller 62 and the second calendering roller 72, and is configured to cause the new upper film 61 upstream of the second calendering roller 72 to tend to move away from the second calendering roller 72.

[0082] In this embodiment, the third unwinding unit 60 is provided with a second transition roller 63, and the second transition roller 63 is configured to make the new upper film 61 located upstream of the second calendering roller 72 tend to move away from the second calendering roller 72, so that the new upper film 61 is in a straightened state before calendering, thereby helping to improve the calendering effect of the film material; in addition, the second transition roller 63 is configured to be rotatable, which can reduce the friction between the contact surface of the second transition roller 63 and the new upper film 61, thereby better protecting the new upper film 61.

[0083] It should be noted that the structural or functional units in the thermally conductive and microwave-absorbing composite film preparation device 1 that are not specifically described or limited are not limited and can be set up in accordance with the conventional selection in the field.

[0084] As an example, both the first calendering unit 40 and the second calendering unit 70 are provided with a conveying mechanism that can move up and down to adjust the calendering gap between the first calendering roll 42 and the second calendering roll 72 and the calendering platform 31, so as to realize the preparation of products with different thicknesses.

[0085] Secondly, embodiments of this application provide a method for preparing a thermally conductive and microwave-absorbing composite film, which is prepared using the thermally conductive and microwave-absorbing composite film preparation apparatus provided in the first aspect embodiment, and includes the following steps:

[0086] The system drives a first unwinding unit and a second unwinding unit to provide an upper film and a bottom film; applies molten thermally conductive phase change material onto the bottom film and drives a film conveying unit so that the upper film, bottom film, and thermally conductive phase change material all undergo a first calendering process in a first calendering unit to obtain a film intermediate; drives a peeling unit to peel off the upper film after the first calendering process to obtain a film precursor; drives a third unwinding unit to provide a new upper film; applies microwave absorbing material onto the film precursor and drives a film conveying unit so that the new upper film and the film precursor carrying the microwave absorbing material both undergo a second calendering process in a second calendering unit; and drives a film conveying unit so that the film precursor after the second calendering process enters a heating and curing unit for curing and shaping.

[0087] In this application, the thermally conductive and microwave-absorbing composite membrane material preparation apparatus provided in the first aspect embodiment is used to prepare the thermally conductive and microwave-absorbing composite membrane material according to the above process. This eliminates the need to prepare the thermally conductive phase change material membrane and the microwave-absorbing material membrane in steps in advance, and also eliminates the need for the artificial superposition of the two membrane materials with the help of auxiliary agents. This can improve the performance of the prepared thermally conductive and microwave-absorbing composite membrane material to a certain extent, while also improving production efficiency and the quality of the prepared product to a certain extent.

[0088] It should be noted that the steps or processes in the preparation method of thermally conductive and microwave-absorbing composite membranes that are not specifically described or limited are not limited and can be set according to the conventional selection in this field.

[0089] The technical solution of this application will be further described below through specific embodiments.

[0090] Example 1

[0091] This application provides a method for preparing a thermally conductive and microwave-absorbing composite film, comprising the following steps:

[0092] The system drives the first and second unwinding units to provide an upper film (PET release film) and a bottom film (PET release film); molten thermally conductive phase change material (a mixture of alumina, boron nitride, and crystalline wax) is applied to the bottom film, and the film conveying unit is driven so that the upper film, bottom film, and thermally conductive phase change material all undergo a first calendering process in the first calendering unit to obtain a film intermediate; the system drives the peeling unit to peel off the upper film after the first calendering process to obtain a film precursor; the system drives the third unwinding unit to provide a new upper film (PET release film); microwave absorbing material (a mixture of carbonyl iron and barium ferrite) is applied to the film precursor, and the film conveying unit is driven so that the new upper film and the film precursor carrying the microwave absorbing material undergo a second calendering process in the second calendering unit; and the system drives the film conveying unit so that the film precursor after the second calendering process enters the heating and curing unit for curing and shaping.

[0093] Comparative Example 1

[0094] This application provides a comparative example of a method for preparing a thermally conductive and microwave-absorbing composite film, comprising the following steps:

[0095] The thermally conductive phase change material (a mixture of alumina, boron nitride, and polyethylene glycol) and the microwave absorbing material (a mixture of carbonyl iron, barium ferrite, and silicone oil) are prepared into thermally conductive films and microwave absorbing films respectively using a calendering equipment. Then, an adhesive (silane coupling agent) is coated on the surface of the thermally conductive film, and the thermally conductive film and the microwave absorbing film are manually stacked. Finally, they are placed in a heating and curing unit for curing and shaping.

[0096] Experimental Example 1

[0097] Membrane material performance testing

[0098] Test method:

[0099] Thermally conductive and microwave-absorbing composite membranes were prepared according to the preparation methods of Example 1 and Comparative Example 1, respectively. The prepared membranes were then numbered, and the thermal conductivity and microwave absorption properties of the different sample membranes were tested.

[0100] The thermal conductivity test was conducted in accordance with ASTM D 5470, and the microwave absorption test was conducted in accordance with GJB2038A-2011.

[0101] The performance of the thermally conductive film, the microwave absorbing film, and the artificially superimposed thermally conductive and microwave absorbing composite film corresponding to Comparative Example 1 are shown in Tables 1-3, respectively:

[0102] Table 1. Statistical Table of Performance Results of Thermal Conductive Film Materials

[0103] 1 1.92 4.98 2 2.01 5.02 3 2.05 5.06

[0104] It should be noted that samples 1 to 3 correspond to test samples with three different test thicknesses.

[0105] Table 2 Statistical Table of Performance Results of Wave Absorbing Membrane Materials

[0106]

[0107]

[0108] Table 3 Statistical Table of Performance Results of Composite Membrane Materials

[0109] 1 1.92 2.48 -6.51 2 2.01 2.34 -6.48 3 2.05 2.12 -6.56

[0110] The performance of the thermally conductive and microwave-absorbing composite membrane material corresponding to Example 1 is shown in Table 4:

[0111] Table 4. Statistical Table of Performance Results of Composite Membrane Materials

[0112] 1 1.92 4.77 -11.61 2 2.01 4.84 -11.55 3 2.05 4.82 -11.59

[0113] Referring to Tables 1 to 4, the test results from Tables 1 and 3, and Tables 2 and 3 respectively show that after the shaped thermally conductive film and the shaped microwave absorbing film are artificially stacked, the thermal conductivity and microwave absorption performance both decrease by about 50% compared to before the artificial stacking.

[0114] As can be seen from the test results in Tables 1 to 4, the thermal conductivity and wave absorption properties of the thermally conductive and wave-absorbing composite membrane prepared by the method provided in the embodiments of this application are basically the same as those of the single material. Moreover, the thermal conductivity and wave absorption properties of the corresponding membrane are significantly better than those of the thermally conductive and wave-absorbing composite membrane prepared by the traditional artificial stacking molding process.

[0115] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for preparing a thermally conductive and microwave-absorbing composite film, characterized in that, The apparatus for preparing thermally conductive and microwave-absorbing composite films includes: A first unwinding unit and a second unwinding unit are respectively used to provide an upper film and a bottom film; A base, the top of which is provided with a calendering platform for supporting the film material; A membrane material conveying unit is installed on the base to transport the membrane material supported on the calendering platform along the conveying direction; The first calendering unit, located downstream of the first unwinding unit and the second unwinding unit along the film material conveying direction, is used to perform the first calendering of the upper film, the bottom film, and the molten thermally conductive phase change material between the upper film and the bottom film on the calendering platform. A peeling unit, located downstream of the first calendering unit along the conveying direction of the film material, is configured to peel off the upper film after the first calendering. The third unwinding unit is located downstream of the peeling unit along the conveying direction of the film material, and is used to provide a new top film. The second calendering unit, located downstream of the third unwinding unit along the conveying direction of the film material, is used to perform a second calendering of the base film, the new upper film, and the thermally conductive phase change material film and microwave absorbing material between the new upper film and the base film on the calendering platform; and A heating and curing unit is located downstream of the third unwinding unit along the conveying direction of the film material. It is used to heat and cure the thermally conductive phase change material film and the microwave absorbing material film after the second calendering. The preparation method of the thermally conductive and microwave-absorbing composite film includes the following steps: Drive the first unwinding unit and the second unwinding unit to provide the upper film and the bottom film; The molten thermally conductive phase change material is applied to the bottom film and the film conveying unit is driven so that the top film, the bottom film and the thermally conductive phase change material are all calendered for the first time through the first calendering unit to obtain the film intermediate. The peeling unit is driven to peel off the upper film after the first calendering to obtain the film precursor. Drive the third unwinding unit to provide the new top film; The microwave absorbing material is applied to the membrane precursor and the membrane conveying unit is driven so that both the new membrane and the membrane precursor carrying the microwave absorbing material undergo a second calendering process via the second calendering unit; and The membrane material conveying unit is driven so that the membrane material precursor after the second calendering enters the heating and curing unit for curing and shaping.

2. The method for preparing the thermally conductive and microwave-absorbing composite film according to claim 1, characterized in that, The first calendering unit includes a first mounting bracket and a first calendering roll. The first mounting bracket is mounted on the base. The first calendering roll is rotatably connected to the first mounting bracket and is located above the calendering platform and has a calendering gap. The first unwinding roll in the first unwinding unit is rotatably connected to the first mounting bracket.

3. The method for preparing the thermally conductive and microwave-absorbing composite film according to claim 2, characterized in that, The first unwinding unit further includes a first transition roller, which is rotatably connected to the first mounting bracket. The first transition roller is located between the first unwinding roller and the first calendering roller, and the first transition roller is configured to cause the upper film upstream of the first calendering roller to tend to move away from the first calendering roller.

4. The method for preparing the thermally conductive and microwave-absorbing composite film according to any one of claims 1 to 3, characterized in that, The thermally conductive and microwave-absorbing composite film preparation device further includes a heating unit located upstream of the first calendering unit along the conveying direction of the film and used to heat and melt the thermally conductive phase change material.

5. The method for preparing the thermally conductive and microwave-absorbing composite film according to claim 2, characterized in that, The peeling unit includes a peeling roller and a take-up roller. The peeling roller is mounted on top of the base and configured to peel the upper film after the first calendering. The take-up roller is rotatably connected to the first mounting bracket and configured to take up the peeled upper film.

6. The method for preparing the thermally conductive and microwave-absorbing composite film according to claim 5, characterized in that, The thermally conductive and microwave-absorbing composite membrane preparation device further includes an auxiliary peeling unit. Along the conveying direction of the membrane, the auxiliary peeling unit is located downstream of the peeling roller. The auxiliary peeling unit is installed on the top of the base and is configured to separate the partially peeled upper membrane from the end of the thermally conductive phase change material membrane that is in contact with it.

7. The method for preparing the thermally conductive and microwave-absorbing composite film according to claim 6, characterized in that, The auxiliary peeling unit includes a second mounting bracket and a peeling plate. The second mounting bracket is connected to the top of the base, and the peeling plate is connected to the second mounting bracket. The peeling plate is configured to separate the partially peeled upper film from the end of the thermally conductive phase change material film that is in contact with it.

8. The method for preparing the thermally conductive and microwave-absorbing composite film according to claim 7, characterized in that, The peeling plate includes a peeling section near the peeling roller and a mounting section away from the peeling roller. The mounting section is connected to the second mounting bracket. The thickness of the peeling section gradually decreases from the end away from the peeling roller to the end near the peeling roller, so that the ends of the partially peeled upper film and the thermally conductive phase change material film in contact can be separated.

9. The method for preparing the thermally conductive and microwave-absorbing composite film according to claim 8, characterized in that, The lower surface of the peeling plate is parallel to the table surface of the calendering platform, and the angle α between the side surface of the peeling section away from the calendering platform and the table surface of the calendering platform is 15~25°.

10. The method for preparing the thermally conductive and microwave-absorbing composite film according to any one of claims 1 to 3, characterized in that, The second calendering unit includes a third mounting bracket and a second calendering roll. The third mounting bracket is mounted on the base. The second calendering roll is rotatably connected to the third mounting bracket and is located above the calendering platform and has a calendering gap. The third unwinding roll in the third unwinding unit is rotatably connected to the third mounting bracket.

11. The method for preparing a thermally conductive and microwave-absorbing composite film according to claim 10, wherein the third unwinding unit further comprises a second transition roller, the second transition roller being rotatably connected to the third mounting bracket, the second transition roller being located between the third unwinding roller and the second calendering roller, and the second transition roller being configured to cause the new film upstream of the second calendering roller to have a tendency to move away from the second calendering roller.

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