A multilayer flexible phase change material with high enthalpy and high thermal conductivity and its preparation method

Abstract

The present invention relates to the technical field of flexible phase change material preparation, and in particular to a multilayer flexible phase change material with both high enthalpy and high thermal conductivity and a preparation method thereof. The method comprises: heating paraffin wax at a preset melting temperature to obtain liquid paraffin wax at a constant temperature, adding a linear triblock copolymer to the liquid paraffin and stirring it at a constant temperature to obtain a first mixture, and pressing the first mixture into a film form using a press to obtain a first film; adding expanded graphite powder to the first mixture in a constant temperature state at a uniform speed, and continuously stirring until the mixture is uniformly mixed to obtain a second mixture, and pressing the second mixture into a film form using a press to obtain a second film; stacking the films and placing them on an intelligent temperature-controlled electric heating plate, and bonding them to each other by relying on the viscosity of the films themselves to obtain a block object; and cutting the alternately stacked and bonded block objects along a direction parallel to the stacking direction to obtain a multilayer flexible phase change material with both high enthalpy and high thermal conductivity.

Description

Technical Field

[0001] The present invention relates to the technical field of flexible phase change materials, and in particular to a multilayer flexible phase change material with high enthalpy value and high thermal conductivity and a preparation method thereof. Background Art

[0002] Phase change materials (PCMs) have attracted widespread attention due to their ability to absorb or release large amounts of latent heat during phase changes. In the field of energy storage and utilization, they are considered a highly efficient thermal energy storage medium, with great potential for resolving the mismatch between energy supply and demand in time and space. Traditional PCMs, such as many organic PCMs (typically paraffin), while possessing high enthalpy values ​​and capable of storing large amounts of heat, have low thermal conductivity. This results in slow heat transfer during the absorption and release of heat, making the phase change process inefficient and limiting their application in scenarios requiring rapid thermal response.

[0003] Chinese patent application publication number: CN109686840A discloses a flexible multi-layer composite GeTe / ZnSb phase change thin film material and its preparation method. The thin film material is composed of GeTe thin film layers and ZnSb thin film layers deposited alternately. The thickness of the GeTe thin film layer is 1-10nm, the thickness of the ZnSb thin film layer is 1-10nm, and the total thickness of the GeTe / ZnSb phase change thin film material is 40-60nm. The thin film material prepared by this invention has good thermal stability and low power consumption, and is an ideal phase change memory material.

[0004] It can be seen that the existing technology has the problem of inaccurate analysis of the flexible phase change material stacking process, resulting in low performance of the stacked flexible phase change material. Summary of the Invention

[0005] To this end, the present invention provides a multilayer flexible phase change material with high enthalpy value and high thermal conductivity and a preparation method thereof, so as to overcome the problem in the prior art that the analysis of the flexible phase change material stacking process is not accurate enough, resulting in low performance of the stacked flexible phase change material.

[0006] To achieve the above objectives, the present invention provides a method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity, comprising:

[0007] Heating paraffin wax at a preset melting temperature to obtain liquid paraffin wax, adding a linear triblock copolymer to the liquid paraffin wax and stirring the mixture at a constant temperature to obtain a first mixture, and pressing the first mixture into a film form using a press to obtain a first film;

[0008] adding expanded graphite powder to the first mixture at a constant temperature at a uniform speed, and continuously stirring until the mixture is uniformly mixed to obtain a second mixture, and pressing the second mixture into a film form using a press to obtain a second film;

[0009] The first film, the second film, and the first film are stacked in this order, and then placed on an intelligent temperature-controlled electric heating plate. The films are bonded to each other by their own viscosity to form a block object.

[0010] When stacking films, determining whether to process the film based on the area ratio of wrinkles or bubbles on the topmost film when the films are stacked in single layers, and under the condition that the film is determined to be processed, determining whether to replace the corresponding type of film, or to remove the wrinkled or bubbled film, based on whether the location of the wrinkles or bubbles on the film to be processed is in the central area, and whether there is a film below the film to be processed that needs to be processed by removing wrinkles or bubbles, or making a secondary determination on the processing method for the film to be processed, wherein the processing method includes replacing the corresponding type of film or removing the wrinkled or bubbled film;

[0011] When the treatment method of the film to be treated is secondarily determined, the corresponding type of film or the film with wrinkles or bubbles removed is determined based on the mapped overlapping area of ​​the lower film of the film to be treated with the film having wrinkles or bubbles removed;

[0012] The block objects that are alternately stacked and bonded together are cut along a direction parallel to the stacking direction to obtain a multilayer flexible phase change material with high enthalpy value and high thermal conductivity.

[0013] Further, the determining whether to process the film includes:

[0014] If the area ratio of wrinkles or bubbles in the topmost film when the films are stacked in single layers is greater than or equal to a preset area ratio, it is determined that the film needs to be processed.

[0015] Furthermore, under the condition of determining to process the film, determining to replace the corresponding type of film, cutting off the film with wrinkles or bubbles, or performing a secondary determination on the processing method of the film to be processed includes:

[0016] If the location of wrinkles or bubbles in the film to be treated is in the central area, or the film below the film to be treated does not have a wrinkle or bubble portion removed and the locations of wrinkles or bubbles in the film to be treated are unevenly distributed, determine to replace the corresponding type of film;

[0017] If the lower film of the film to be processed does not have a film portion to be processed by removing wrinkles or bubbles and the locations of wrinkles or bubbles in the film to be processed are evenly distributed, determine to remove the film portion to be processed by removing wrinkles or bubbles;

[0018] If the location of wrinkles or bubbles in the film to be processed is not in the central area and the underlying film to be processed has wrinkles or bubbles removed, a secondary determination is made on the processing method for the film to be processed.

[0019] Furthermore, the second determination of the treatment method of the film to be treated includes:

[0020] If the mapping overlap area ratio of the lower film processed by removing the wrinkle or bubble part of the film is less than the preset area ratio, it is determined to remove the wrinkle or bubble part of the film;

[0021] If the mapping overlap area ratio of the lower film processed by removing wrinkles or bubbles is greater than or equal to the preset area ratio, it is determined to replace the corresponding type of film.

[0022] Furthermore, the mapping overlap area ratio of the lower film with the wrinkles or bubbles cut out is the ratio of the sum of the area of ​​the film with the wrinkles or bubbles cut out mapped to the lower film and the area of ​​the lower film with the wrinkles or bubbles cut out to the face value of the lower film. The overlapping area of ​​the area of ​​the film with the wrinkles or bubbles cut out mapped to the lower film and the area of ​​the lower film with the wrinkles or bubbles cut out does not need to be calculated repeatedly.

[0023] Furthermore, determining whether the location where wrinkles or bubbles appear on the film to be processed is in the central area includes:

[0024] Based on the shape of the film to be processed and determine the geometric center;

[0025] Taking the geometric center as the origin, divide the area with the same shape as the film to be treated as the central area range, and the area of ​​the central area range is set to four-fifths of the area of ​​the film to be treated;

[0026] Use a marking tool to record where wrinkles or bubbles are;

[0027] The position of the marked wrinkles or bubbles is compared with the previously divided central area to determine whether it is in the central area.

[0028] Further, judging whether the locations where wrinkles or bubbles appear on the film to be processed are evenly distributed includes determining that the locations where wrinkles or bubbles appear on the film to be processed are evenly distributed when a maximum distance between wrinkles or bubbles appearing on the film to be processed is less than a preset distance.

[0029] Furthermore, the preset distance is determined according to the diagonal distance of the film to be processed.

[0030] Furthermore, when the first film, the second film, and the first film are stacked in sequence, they are placed in a relatively closed space or a windproof cover device is used to reduce air flow.

[0031] A multilayer flexible phase change material with high enthalpy and high thermal conductivity obtained by the method for preparing the multilayer flexible phase change material with high enthalpy and high thermal conductivity comprises: the components of the multilayer flexible phase change material with high enthalpy and high thermal conductivity are 76 to 80 parts by weight of paraffin, 19 to 20 parts of a linear triblock copolymer, and 0 to 6 parts of expanded graphite.

[0032] Compared with the prior art, the beneficial effect of the present invention is that the present invention determines whether to process the film by comparing the area ratio of wrinkles or bubbles on the top film with the preset area ratio, and can clearly quantify the quality standard of the film. When the area ratio is greater than or equal to the preset area ratio, it is processed, and when it is less than the preset area ratio, it is not processed. This clear judgment standard helps to ensure the quality stability of the final product. For example, in actual production, it can avoid the problem of uneven product performance due to unclear quality standards, so that each batch of multi-layer flexible phase change materials can be at a relatively consistent quality level. For multi-layer flexible phase change materials, wrinkles or bubbles on the surface of the film may affect the thermal conductivity, mechanical strength and overall reliability of the material. Through this precise judgment and processing method, defects that may have a greater impact on product performance can be discovered and processed in time, reducing the risk of product failure during use. Through the above process, the accuracy of the analysis of the flexible phase change material stacking process is improved, thereby improving the performance of the stacked flexible phase change material.

[0033] Furthermore, the present invention determines a specific treatment method based on the location of wrinkles or bubbles in the film to be treated and the treatment status of the underlying film, which can more specifically solve film quality problems. If the wrinkles or bubbles are located in the central area, or the location distribution is uneven and the underlying film has not been treated, directly replacing the corresponding type of film can ensure the stable quality of the core area of ​​the material and avoid affecting the overall performance due to local defects. For example, in a multi-layer flexible phase change material, quality problems in the central area may have a greater negative impact on key properties such as heat conduction and energy storage. Timely replacement of the film can effectively ensure these properties. For the case where the underlying film is untreated and the location of wrinkles or bubbles is evenly distributed, the wrinkled or bubbled part of the film is selected to be removed. This can maintain the integrity and performance of the material without wasting a large amount of material. This treatment method not only solves the problem of local defects, but also reduces the cost and resource waste caused by replacing the entire film. At the same time, a secondary judgment is performed for specific situations, and the treatment method can be determined more precisely, further improving product quality and performance. Through the above process, the accuracy of the analysis of the flexible phase change material stacking process is improved, thereby improving the performance of the stacked flexible phase change material.

[0034] Furthermore, the present invention determines the final treatment method by comparing the mapping overlap area ratio of the lower film processed with the removed wrinkle or bubble part with the preset area ratio, so that the treatment of the problem film is more accurate. This secondary judgment mechanism can select the most appropriate treatment method according to the specific defect situation under complex production conditions, avoiding the problems of over-treatment or under-treatment that may be caused by a single treatment method, thereby effectively improving the quality of the product. For example, if the treatment method is determined based on only one judgment, the severity of the problem may be misjudged in some cases, resulting in unnecessary material waste or deterioration of product quality, while the secondary judgment can be more accurate. Accurately evaluate the problem, ensure the stability of product performance, clarify the calculation method of the mapping overlap area ratio of the lower film treated by removing wrinkles or bubbles, and provide a scientific basis for judgment. This calculation method takes into account the relationship between the film to be treated and the lower film, and can more comprehensively evaluate the severity of the problem. For example, by calculating the overlap area ratio, it can be determined whether the problem is concentrated in a specific area or whether it has spread to a larger area, thereby providing an accurate reference for choosing whether to remove part of the film or replace the entire film. Through the above process, the accuracy of the analysis of the flexible phase change material stacking process is improved, thereby improving the performance of the flexible phase change material after stacking. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a workflow diagram of a method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to an embodiment of the present invention;

[0036] Figure 2 This is a flowchart for determining whether the location where wrinkles or bubbles appear in a film to be processed is in the central area in the method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to an embodiment of the present invention;

[0037] Figure 3 This is a flowchart for determining whether to process a film in a method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention.

[0039] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0040] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside", and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0041] Furthermore, it should be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0042] See also Figure 1-Figure 3 As shown, Figure 1 This is a workflow diagram of a method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to an embodiment of the present invention; Figure 2 This is a flowchart for determining whether the location where wrinkles or bubbles appear in a film to be processed is in the central area in the method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to an embodiment of the present invention; Figure 3 This is a flowchart for determining whether to process a film in a method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to an embodiment of the present invention.

[0043] The method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to an embodiment of the present invention includes:

[0044] Step S1, heating paraffin wax at a preset melting temperature to obtain liquid paraffin wax, adding a linear triblock copolymer to the liquid paraffin wax and stirring the mixture at a constant temperature to obtain a first mixture, and pressing the first mixture into a film form using a press to obtain a first film;

[0045] Step S2, adding expanded graphite powder to the first mixture at a constant temperature at a uniform speed, and continuously stirring until the mixture is uniformly mixed to obtain a second mixture, and pressing the second mixture into a film form using a press to obtain a second film;

[0046] Step S3, stacking the first film, the second film, and the first film in order, and then placing them on an intelligent temperature-controlled electric heating plate, and relying on the viscosity of the films to adhere to each other to form a block object;

[0047] Step S4, when stacking films, determining whether to process the films based on the area ratio of wrinkles or bubbles on the topmost film when the films are stacked as single layers, and under the condition that the films are determined to be processed, determining whether to replace the corresponding type of film, or to remove the wrinkled or bubbled film, or making a secondary determination on the processing method for the films to be processed, based on whether the location of the wrinkles or bubbles on the film to be processed is in the central area, and whether there is a film below the film to be processed that needs to be processed by removing wrinkles or bubbles;

[0048] Step S5, when the treatment method of the film to be treated is secondarily determined, the corresponding type of film or the film with the wrinkles or bubbles removed is determined based on the mapped overlapping area of ​​the underlying film of the film to be treated.

[0049] Step S6: cutting the alternately stacked and bonded block objects along a direction parallel to the stacking direction to obtain a multilayer flexible phase change material with high enthalpy and high thermal conductivity.

[0050] In the embodiment of the present invention, the preset melting temperature is set to 70°C, the heating time is 10 minutes, the stirring temperature in step S2 is 130°C; and the mass ratio of the added paraffin wax to the linear triblock copolymer is 4:1. In step S3, the temperature of the temperature-controlled electric heating plate is 60°C, and the standing time is 5 minutes.

[0051] In the embodiment of the present invention, 94 parts of a homogeneous mixture of paraffin wax and a linear triblock copolymer were taken out, 6 parts of expanded graphite were added thereto, and the mixture was stirred at a constant temperature and constant speed for 10 minutes. The oil bath temperature of the magnetic stirrer was 130°C and the stirring speed was 60 revolutions per minute. The paraffin wax, the linear triblock copolymer and the expanded graphite film were obtained by pressing; 100 parts of a homogeneous mixture of paraffin wax and the linear triblock copolymer were taken out, and the paraffin wax and the linear triblock copolymer film were obtained by pressing. The two films were alternately stacked and placed on an intelligent temperature-controlled electric heating plate at 60°C for a standing time. The method comprises the following steps: heating the paraffin wax, the linear triblock copolymer, the expanded graphite film, and the paraffin in the paraffin wax and the linear triblock copolymer film for 5 minutes, so that the paraffin wax and the linear triblock copolymer film complete the phase change and are bonded together by their own viscosity; cutting the blocks of the paraffin wax and the linear triblock copolymer film and the paraffin wax, the linear triblock copolymer, and the expanded graphite film alternately stacked in sequence in a direction parallel to the stacking direction to obtain a multilayer flexible phase change material with high enthalpy and high thermal conductivity, named 0EG@6EG-1; preferably, the thickness of 100 parts of the material is 1 mm.

[0052] Specifically, in step S4, when determining whether to process the film, the determination of whether to process the film is based on a comparison result of the area ratio of wrinkles or bubbles on the topmost film when the films are stacked in a single layer with a preset area ratio;

[0053] When wrinkles or bubbles appear on the topmost layer of the film in a single-layer stack, the film is determined to need to be processed if the area ratio is greater than or equal to a preset area ratio;

[0054] When the area ratio of wrinkles or bubbles on the topmost film of a single-layer stacked film is less than a preset area ratio, it is determined that the film does not need to be processed;

[0055] Among them, the value range of the preset area ratio is set to 0.01, but the above value is not limited to this. Those skilled in the art can also adjust the value according to actual needs.

[0056] The present invention determines whether to process the film by comparing the area ratio of wrinkles or bubbles on the top film with a preset area ratio. It can clearly quantify the quality standard of the film. When the area ratio is greater than or equal to the preset area ratio, it is processed, and when it is less than the preset area ratio, it is not processed. This clear judgment standard helps to ensure the quality stability of the final product. For example, in actual production, it can avoid the problem of uneven product performance due to unclear quality standards, so that each batch of multi-layer flexible phase change materials can be at a relatively consistent quality level. For multi-layer flexible phase change materials, wrinkles or bubbles on the surface of the film may affect the thermal conductivity, mechanical strength and overall reliability of the material. Through this precise judgment and processing method, defects that may have a greater impact on product performance can be discovered and processed in time, reducing the risk of product failure during use. Through the above process, the accuracy of the analysis of the flexible phase change material stacking process is improved, thereby improving the performance of the stacked flexible phase change material.

[0057] Specifically, in step S4, when it is determined to replace the corresponding type of film, cut off the wrinkled or bubbled portion of the film, or perform a secondary determination on the treatment method of the film to be treated, it is determined to replace the corresponding type of film, cut off the wrinkled or bubbled portion of the film, or perform a secondary determination on the treatment method of the film to be treated based on whether the location where the wrinkles or bubbles appear on the film to be treated is in the central area and whether there is a film below the film to be treated that has the wrinkles or bubbles cut off.

[0058] When the location of wrinkles or bubbles in the film to be treated is in the central area, or the lower film of the film to be treated does not have a film treatment in which wrinkles or bubbles are removed and the locations of wrinkles or bubbles in the film to be treated are unevenly distributed, it is determined to replace the corresponding type of film;

[0059] When the lower film of the film to be processed does not have a film portion to be processed by cutting out wrinkles or bubbles and the locations of wrinkles or bubbles in the film to be processed are evenly distributed, it is determined to cut out the film portion with wrinkles or bubbles;

[0060] When the location of wrinkles or bubbles in the film to be processed is not in the central area and the underlying film of the film to be processed has a portion of the film with wrinkles or bubbles cut out for processing, a secondary determination is made on the processing method of the film to be processed.

[0061] Specifically, in step S4, determining whether the location where wrinkles or bubbles appear on the film to be processed is in the central area includes:

[0062] Step S4401, determining the geometric center based on the shape of the film to be processed;

[0063] Step S4402: With the geometric center as the origin, a region having the same shape as the film to be processed is divided as a central region range, and the area of ​​the central region range is set to four-fifths of the area of ​​the film to be processed;

[0064] Step S4403, using a marking tool to record the location of wrinkles or bubbles;

[0065] Step S4404: Compare the position of the marked wrinkles or bubbles with the previously divided central area range to determine whether they are in the central area.

[0066] Specifically, in step S4, determining whether the locations of wrinkles or bubbles appearing on the film to be processed are evenly distributed includes determining that the locations of wrinkles or bubbles appearing on the film to be processed are evenly distributed when the maximum distance between wrinkles or bubbles appearing on the film to be processed is less than a preset distance.

[0067] In the embodiment of the present invention, the preset distance is one twentieth of the diagonal distance of the film to be processed, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0068] The present invention determines a specific treatment method based on the location of wrinkles or bubbles in the film to be treated and the treatment status of the underlying film, which can more specifically solve film quality problems. If the wrinkles or bubbles are located in the central area, or the location distribution is uneven and the underlying film has not been treated, directly replacing the corresponding type of film can ensure the stable quality of the core area of ​​the material and avoid the overall performance being affected by local defects. For example, in a multi-layer flexible phase change material, quality problems in the central area may have a greater negative impact on key properties such as heat conduction and energy storage. Timely replacement of the film can effectively ensure these properties. If the underlying film is untreated and the wrinkles or bubbles are evenly distributed, the wrinkled or bubbled portion of the film is selectively removed. This can maintain the integrity and performance of the material without wasting a large amount of material. This treatment method not only solves the problem of local defects, but also reduces the cost and resource waste caused by replacing the entire film. At the same time, a secondary judgment for specific situations can more accurately determine the treatment method, further improving product quality and performance. Through the above process, the accuracy of the analysis of the flexible phase change material stacking process is improved, thereby improving the performance of the stacked flexible phase change material.

[0069] Specifically, in step S5, when a secondary determination is made on the treatment method of the film to be treated, the film to be treated with the wrinkles or bubbles is determined to be removed or replaced with the corresponding type of film based on the comparison result of the mapped overlapping area ratio of the underlying film to be treated with the wrinkles or bubbles removed portion and the preset area ratio;

[0070] When the mapping overlap area ratio of the lower film where the wrinkle or bubble portion is removed is less than the preset area ratio, it is determined to remove the wrinkle or bubble portion of the film;

[0071] When the mapping overlap area ratio of the lower film processed by removing wrinkles or bubbles is greater than or equal to the preset area ratio, it is determined to replace the corresponding type of film.

[0072] In the embodiment of the present invention, the mapping overlap area ratio of the lower film with the wrinkles or bubbles cut out is the ratio of the sum of the area of ​​the film with the wrinkles or bubbles cut out mapped to the lower film and the area of ​​the film with the wrinkles or bubbles cut out of the lower film to the face value of the lower film. The overlapping area of ​​the area of ​​the film with the wrinkles or bubbles cut out mapped to the lower film and the area of ​​the film with the wrinkles or bubbles cut out of the lower film does not need to be calculated repeatedly.

[0073] In the embodiment of the present invention, the first film, the second film, and the first film are stacked in sequence in a relatively closed space or a windproof cover device is used to reduce air flow.

[0074] The present invention determines the final treatment method by comparing the mapped overlap area ratio of the underlying film treated with the portion of the film with wrinkles or bubbles removed with a preset area ratio, making the treatment of the problem film more accurate. This secondary judgment mechanism can select the most appropriate treatment method according to the specific defect situation under complex production conditions, avoiding the problems of over-treatment or under-treatment that may be caused by a single treatment method, thereby effectively improving product quality. For example, if the treatment method is determined based on only one judgment, the severity of the problem may be misjudged in some cases, resulting in unnecessary material waste or reduced product quality. The secondary judgment can more accurately assess the problem and ensure the stability of product performance. The calculation method for the mapped overlap area ratio of the underlying film treated with the portion of the film with wrinkles or bubbles removed is clarified, providing a scientific basis for judgment. This calculation method takes into account the relationship between the film to be treated and the underlying film and can more comprehensively assess the severity of the problem. For example, by calculating the overlap area ratio, it can be determined whether the problem is concentrated in a specific area or has spread to a larger area, thereby providing an accurate reference for choosing whether to remove part of the film or replace the entire film. Through the above process, the accuracy of the analysis of the flexible phase change material stacking process is improved, thereby improving the performance of the flexible phase change material after stacking.

[0075] Specifically, a multilayer flexible phase change material with high enthalpy and high thermal conductivity obtained by the method for preparing the multilayer flexible phase change material with high enthalpy and high thermal conductivity includes: the mass parts of the components of the multilayer flexible phase change material with high enthalpy and high thermal conductivity are 76 to 80 parts of paraffin, 19 to 20 parts of linear triblock copolymer and 0 to 6 parts of expanded graphite.

[0076] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

[0077] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity, characterized in that: include: Heating paraffin wax at a preset melting temperature to obtain liquid paraffin wax, adding a linear triblock copolymer to the liquid paraffin wax and stirring the mixture at a constant temperature to obtain a first mixture, and pressing the first mixture into a film form using a press to obtain a first film; adding expanded graphite powder to the first mixture at a constant temperature at a uniform speed, and continuously stirring until the mixture is uniformly mixed to obtain a second mixture, and pressing the second mixture into a film form using a press to obtain a second film; The first film, the second film, and the first film are stacked in this order, and then placed on an intelligent temperature-controlled electric heating plate. The films are bonded to each other by their own viscosity to form a block object. When stacking films, determining whether to process the film based on the area ratio of wrinkles or bubbles on the topmost film when the films are stacked in single layers, and under the condition that the film is determined to be processed, determining whether to replace the corresponding type of film, or to remove the wrinkled or bubbled film, based on whether the location of the wrinkles or bubbles on the film to be processed is in the central area, and whether there is a film below the film to be processed that needs to be processed by removing wrinkles or bubbles, or making a secondary determination on the processing method for the film to be processed, wherein the processing method includes replacing the corresponding type of film or removing the wrinkled or bubbled film; When the treatment method of the film to be treated is secondarily determined, the corresponding type of film or the film with wrinkles or bubbles removed is determined based on the mapped overlapping area of ​​the lower film of the film to be treated with the film having wrinkles or bubbles removed; The block objects that are alternately stacked and bonded together are cut along a direction parallel to the stacking direction to obtain a multilayer flexible phase change material with high enthalpy value and high thermal conductivity.

2. The method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to claim 1, characterized in that: The determining whether to process the film comprises: If the area ratio of wrinkles or bubbles in the topmost film when the films are stacked in single layers is greater than or equal to a preset area ratio, it is determined that the film needs to be processed.

3. The method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to claim 2, characterized in that: Under the condition of determining to process the film, the determining to replace the corresponding type of film, to cut off the film with wrinkles or bubbles, or to perform a secondary determination on the processing method of the film to be processed includes: If the location of wrinkles or bubbles in the film to be treated is in the central area, or the film below the film to be treated does not have a wrinkle or bubble portion removed and the locations of wrinkles or bubbles in the film to be treated are unevenly distributed, determine to replace the corresponding type of film; If the lower film of the film to be processed does not have a film portion to be processed by removing wrinkles or bubbles and the locations of wrinkles or bubbles in the film to be processed are evenly distributed, determine to remove the film portion to be processed by removing wrinkles or bubbles; If the location of wrinkles or bubbles in the film to be processed is not in the central area and the underlying film to be processed has wrinkles or bubbles removed, a secondary determination is made on the processing method for the film to be processed.

4. The method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to claim 3, characterized in that: The secondary determination of the treatment method of the film to be treated includes: If the mapping overlap area ratio of the lower film processed by removing the wrinkle or bubble part of the film is less than the preset area ratio, it is determined to remove the wrinkle or bubble part of the film; If the mapping overlap area ratio of the lower film processed by removing wrinkles or bubbles is greater than or equal to the preset area ratio, it is determined to replace the corresponding type of film.

5. The method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to claim 4, characterized in that: The mapping overlap area ratio of the lower film with the wrinkles or bubbles cut out is the ratio of the sum of the area of ​​the film with the wrinkles or bubbles cut out mapped to the lower film and the area of ​​the lower film with the wrinkles or bubbles cut out to the face value of the lower film. The overlapping area of ​​the area of ​​the film with the wrinkles or bubbles cut out mapped to the lower film and the area of ​​the lower film with the wrinkles or bubbles cut out does not need to be calculated repeatedly.

6. The method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to claim 1, characterized in that: Determining whether the location where wrinkles or bubbles appear on the film to be treated is in the central area includes: Based on the shape of the film to be processed and determine the geometric center; Taking the geometric center as the origin, divide the area with the same shape as the film to be treated as the central area range, and the area of ​​the central area range is set to four-fifths of the area of ​​the film to be treated; Use a marking tool to record where wrinkles or bubbles are; The position of the marked wrinkles or bubbles is compared with the previously divided central area to determine whether it is in the central area.

7. The method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to claim 3, characterized in that: Determining whether the locations where wrinkles or bubbles appear on the film to be processed are evenly distributed includes determining that the locations where wrinkles or bubbles appear on the film to be processed are evenly distributed when a maximum distance between wrinkles or bubbles appearing on the film to be processed is less than a preset distance.

8. The method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to claim 7, characterized in that: The preset distance is determined according to the diagonal distance of the film to be processed.

9. The method for preparing a multilayer flexible phase change material with high enthalpy and high thermal conductivity according to claim 1, characterized in that: When stacking the first film, the second film, and the first film in sequence, they are placed in a relatively closed space or a windproof cover device is used to reduce air flow.

10. A multi-layer flexible phase change material with high enthalpy and high thermal conductivity obtained by the method for preparing a multi-layer flexible phase change material with high enthalpy and high thermal conductivity according to any one of claims 1 to 9, characterized in that: include: The mass parts of the components of the multilayer flexible phase change material with high enthalpy and high thermal conductivity are 76 to 80 parts of paraffin, 19 to 20 parts of linear triblock copolymer and 0 to 6 parts of expanded graphite.

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