Organic fiber core material pretreatment method, vacuum insulation panel and preparation method of vacuum insulation panel

Abstract

The invention relates to an organic fiber core material pretreatment method, a vacuum insulation panel and a preparation method of the vacuum insulation panel. The organic fiber core material is subjected to vacuum heating treatment, so that the heat conductivity coefficient of the vacuum insulated panel with the organic fiber as the core material is reduced, and the heat insulation performance and the aging resistance of the vacuum insulated panel are improved. Besides, by optimizing the fiber diameter and fiber arrangement of the organic fiber core material and cooperating with the vacuum heating treatment step, the heat conductivity coefficient of the vacuum insulation panel with the organic fiber as the core material is reduced to about 2 mW / (m.K).

Description

Technical Field

[0001] The invention relates to the field of vacuum insulation, and in particular to an organic fiber core material pretreatment method, a vacuum insulation board and a preparation method thereof. Background Art

[0002] Vacuum Insulation Panel (VIP) is a new type of insulation board that has developed rapidly in recent years. It uses the high vacuum inside to reduce air heat convection, the low thermal conductivity core material reduces solid heat conduction, and the high reflective barrier film increases the inhibitory effect on radiation convection while playing the role of water and air isolation to maintain the vacuum degree, so that the internal heat transfer is reduced to the minimum, becoming a low thermal conductivity material that is generally applicable to refrigerators, ships, aviation, construction and other fields. At present, the most widely used vacuum insulation panels on the market are made of glass fiber as the core material, and there are also a small number of products with aerogel materials as the core material. However, these vacuum insulation panels with inorganic materials as the core material have relatively high prices, large dust pollution during the production process, and it is difficult to recycle glass fibers after the products are discarded and they are very irritating to humans. The price of organic fibers is much lower than that of glass fibers and is non-irritating to the human body, but the thermal conductivity of vacuum insulation panels with organic fibers as the core material is generally high, and the insulation performance is poor, which is difficult to meet the current industrial / commercial demand for the performance of vacuum insulation panels. Summary of the invention

[0003] The present invention aims to solve at least one of the above-mentioned technical problems existing in the prior art. To this end, one of the purposes of the present invention is to provide a method for pretreating an organic fiber core material, by which the water vapor, small molecule gas, and large molecule gas adsorbed on the surface and inside of the organic fiber core material can be removed as much as possible, thereby reducing the thermal conductivity of the organic fiber core material and improving the thermal insulation performance.

[0004] A second object of the present invention is to provide a vacuum insulation panel.

[0005] A third object of the present invention is to provide a method for preparing the above-mentioned vacuum insulation panel.

[0006] A fourth object of the present invention is to provide a refrigeration device.

[0007] A fifth object of the present invention is to provide application of the vacuum insulation panel in refrigerators, ships, aviation equipment or building materials.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] The first aspect of the present invention provides a method for pretreating an organic fiber core material, comprising the following steps: vacuum heating the organic fiber core material; in the vacuum heating step, the vacuum degree is not higher than 2000Pa, the heating temperature is not lower than 100°C and does not exceed the thermal deformation temperature of the organic fiber core material.

[0010] One of the technical solutions of the present invention regarding the method for pretreating an organic fiber core material has at least the following beneficial effects: by subjecting the organic fiber core material to vacuum heating treatment, components such as water, small molecule gases, and large molecule gases adsorbed on the surface and inside of the organic fiber core material can be removed as much as possible, and the heat conduction generated by the gas flow on the surface and inside of the organic fiber core material can be reduced as much as possible, thereby reducing the thermal conductivity of the organic fiber core material, thereby meeting the requirements of the vacuum insulation panel for the thermal conductivity of the core material.

[0011] The use of a heating temperature of not less than 100°C and not more than the heat deformation temperature of the organic fiber core material can reduce the boiling point of the gas and liquid inside the organic fiber core material and allow them to escape from the organic fiber core material. If the heating temperature exceeds the heat deformation temperature, the organic fiber core material will fail to crystallize; if the heating temperature is lower than 100°C, the removal effect of the gas and liquid components inside the organic fiber core material is poor, and the residual amount of components such as moisture and gas is still high, resulting in the organic fiber core material still having a high thermal conductivity.

[0012] Pre-treating the organic fiber core material with a vacuum degree not higher than 2000 Pa can enable the organic fiber core material to maintain a high vacuum degree inside for a long time after the pre-treatment, which is beneficial to reducing the thermal conductivity of the organic fiber core material.

[0013] According to some embodiments of the present invention, the heating temperature can be adjusted according to the heat deformation temperature of the organic fiber core material. When selecting the heating temperature, in order to fully remove components such as water and gas inside the organic fiber core material, it is necessary to select a higher heating temperature, but the heating temperature still needs to be lower than the heat deformation temperature of the organic fiber core material to avoid crystallization failure of the organic fiber core material. According to some embodiments of the present invention, the heating temperature is 100 to 190°C. According to some embodiments of the present invention, the heating temperature is 100 to 160°C. At the above heating temperatures, the organic fiber core material will not crystallize and fail, and the effect of removing gas and liquid inside the organic fiber core material is better.

[0014] According to some embodiments of the present invention, the heating time in the vacuum heating treatment step is 0.5 to 5 hours. As the heating time increases, the effect of removing components such as water and gas inside the organic fiber core material is improved, but correspondingly, the production cost also increases. Therefore, considering the comprehensive cost and removal effect, some embodiments of the present invention select a heating time of 0.5 to 5 hours, but the present invention is not limited to this heating time.

[0015] According to some embodiments of the present invention, the vacuum degree is 1000-2000 Pa. According to some embodiments of the present invention, the vacuum degree is 1500-2000 Pa.

[0016] According to some embodiments of the present invention, the organic fiber core material is made by alternately stacking a first fiber layer and a second fiber layer.

[0017] According to some embodiments of the present invention, the angle between the fibers in the first fiber layer and the second fiber layer is 60° to 90°.

[0018] The existing fiber stacking method will cause different fiber layers to nest with each other, and the porosity of the obtained organic fiber core material will be reduced. In addition, the existing organic fiber core material is prone to structural collapse when evacuating, resulting in a high thermal conductivity and poor insulation performance. Some embodiments of the present invention use a first fiber layer (denoted as A) and a second fiber layer (denoted as B) to alternately stack, that is, the stacking structure of the organic fiber core material is ABABAB... The angle between the fibers of the first fiber layer and the fibers of the second fiber layer is 60° to 90°, which can effectively avoid the occurrence of fiber structure collapse, reduced porosity, poor insulation performance, etc. in the organic fiber core material during the vacuum heating treatment stage and the vacuum stage when preparing the vacuum insulation board.

[0019] According to some embodiments of the present invention, the angle between the fibers in the first fiber layer and the second fiber layer is 80° to 90°.

[0020] According to some embodiments of the present invention, the number of layers of the organic fiber core material is 160-200; according to some embodiments of the present invention, the number of layers of the organic fiber core material is 170-190.

[0021] According to some embodiments of the present invention, the diameters of the fibers in the first fiber layer and the second fiber layer are independently 4 to 30 μm; according to some embodiments of the present invention, the diameters of the fibers in the first fiber layer and the second fiber layer are independently 10 to 20 μm. The organic fiber core material is prepared by orthogonally stacking fibers with a diameter of 4 to 30 μm, which can ensure that the structure does not collapse during vacuuming and still retain a high porosity and a relatively stable structural form.

[0022] According to some embodiments of the present invention, the gram weight of the fibers in the first fiber layer and the second fiber layer is independently 10-40 g / m 2 According to some embodiments of the present invention, the gram weight of the fibers in the first fiber layer and the second fiber layer is independently 10-30 g / m 2 According to some embodiments of the present invention, the weight of the fibers in the first fiber layer and the second fiber layer is independently 10-25 g / m2 If the fiber weight is too large or too small, the weight and porosity of the organic fiber core material will not meet the requirements, so that the vacuum insulation panel produced will not meet the requirements of light weight and good insulation performance.

[0023] According to some embodiments of the present invention, the material of the organic fiber core material is selected from at least one of polyester, polypropylene, polyethylene, polystyrene, butadiene, and styrene.

[0024] The second aspect of the present invention provides a vacuum insulation panel, comprising a barrier material and an organic fiber core material vacuum-sealed in the barrier material; the organic fiber core material is an organic fiber core material obtained by the pretreatment method provided by the first aspect of the present invention.

[0025] One of the technical solutions of the present invention regarding vacuum insulation panels has at least the following beneficial effects: the vacuum insulation panel adopts an organic fiber core material that has been subjected to vacuum heating treatment, and the water and gas inside the organic fiber core material are fully removed. During the use of the vacuum insulation panel, there is almost no flow of water and gas inside the organic fiber core material, and the heat conduction is low. The vacuum insulation panel has a low thermal conductivity and good aging resistance. Moreover, the organic fiber core material in the vacuum insulation panel is significantly reduced in the content of gas released under a long-term low-pressure environment. Therefore, the vacuum insulation panel has better aging resistance and can maintain a higher vacuum degree for a longer time.

[0026] According to some embodiments of the present invention, the barrier material is selected from a double-sided aluminized film, a cation-cationic film, and a double-sided aluminum-free film.

[0027] According to some embodiments of the present invention, the vacuum insulation panel has a thickness of 8 to 9 mm.

[0028] According to some embodiments of the present invention, the density of the vacuum insulation panel is 200-250 kg / m 3 .

[0029] According to some embodiments of the present invention, the thermal conductivity of the vacuum insulation panel is 1.9 to 2.2 mW / (m·K).

[0030] The third aspect of the present invention provides a method for preparing the vacuum insulation panel provided in the second aspect of the present invention, comprising the following steps:

[0031] The pretreated organic fiber core material is vacuum-sealed in the barrier material to obtain the vacuum insulation panel.

[0032] A technical solution in the technical solution of the preparation method of the vacuum insulation panel of the present invention has at least the following beneficial effects: the preparation method of the present invention can effectively solve the problem of high thermal conductivity and poor insulation performance of the existing vacuum insulation panel. At the same time, the preparation method of the present invention can effectively reduce the water and other gases inside the organic fiber core material, reduce the heat conduction caused by the flow of water and gas inside the organic fiber core material, and enable the interior of the prepared vacuum insulation panel to maintain a high vacuum state for a long time.

[0033] According to some embodiments of the present invention, the preparation method comprises the following steps: the preparation method comprises the following steps: the pretreated organic fiber core material is loaded into a barrier bag made of barrier material, evacuated to a vacuum degree of 0.0005-1Pa, and sealed.

[0034] According to some embodiments of the present invention, the vacuuming time is 10 to 120 minutes.

[0035] According to some embodiments of the present invention, the sealing step adopts heat pressure sealing.

[0036] According to some embodiments of the present invention, the preparation method further comprises a step of performing a heat treatment after the sealing step.

[0037] According to some embodiments of the present invention, the heat treatment step is performed by hot pressing to roll the barrier material sealed with the organic fiber core material flat.

[0038] A fourth aspect of the present invention provides a refrigeration device, comprising the vacuum insulation panel provided by the second aspect of the present invention.

[0039] According to some embodiments of the present invention, the refrigeration equipment includes a refrigerator, a freezer, a cold storage room, and a refrigerated transport vehicle. The above refrigeration equipment uses the vacuum insulation panel of the present invention as the insulation material, which can make the insulation effect of the refrigeration equipment better.

[0040] The fifth aspect of the present invention provides the use of the vacuum insulation panel provided in the second aspect of the present invention in refrigerators, ships, aviation equipment or building materials. These refrigerators, ships, aviation equipment or building materials have all the characteristics and advantages of the vacuum insulation panel described above.

[0041] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 1 is a flow chart of the preparation process of the vacuum insulation panel in an embodiment of the present invention.

[0043] Figure 2 It is a graph showing the gas release test results of inorganic fibers and organic fibers in an embodiment of the present invention under low pressure.

[0044] Figure 3 This is a graph showing the results of a gas release test under low pressure after the organic fiber in an embodiment of the present invention is subjected to vacuum heating treatment and normal pressure heating treatment. DETAILED DESCRIPTION

[0045] The following will clearly and completely describe the concept and technical effects of the present invention in combination with the accompanying drawings and embodiments, so as to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0046] Existing vacuum insulation panels all use glass fiber as the core material. The cost of glass fiber is relatively high, and after the vacuum insulation panels are discarded, the glass fiber is difficult to recycle. When the glass fiber is processed into the core material of the vacuum insulation panel, glass fiber debris is generated, and these debris are very irritating to the human body.

[0047] In view of the shortcomings of the prior art, the inventors tried to use organic fibers instead of glass fibers. However, when preparing vacuum insulation panels, they found that if the conventional glass fiber processing technology uses a heating and drying method greater than 200°C, although most of the water and gas inside the organic fibers can be removed, the heating temperature is higher than the thermal deformation temperature of the organic fibers. At this temperature, the organic fibers fail to crystallize and cannot be used as organic fiber core materials.

[0048] The inventors also tried to lower the heating temperature and extend the heating time. They dried the organic fibers at a heating temperature lower than the thermal deformation temperature of the organic fibers and used the dried organic fibers as the core material of the vacuum insulation panel. However, this method cannot effectively remove water and gas on the surface and inside of the organic fiber core material. When the obtained vacuum insulation panel is used, the organic fiber core material will release water vapor and other gases, and there will be thermal convection of the gas. Therefore, the thermal conductivity is high and the insulation performance is very poor, which cannot meet the industrial / commercial requirements for vacuum insulation panels.

[0049] The inventors also tried to pretreat the organic fiber core material by vacuuming, and tried pretreatment under different vacuum degrees. They found that the low-boiling-point components adsorbed on the surface and inside of the organic fiber core material could be removed, but the high-boiling-point components still remained inside the organic fiber core material, and these high-boiling-point components were difficult to remove by vacuuming alone.

[0050] The inventors also tried to pretreat the organic fiber core material by combining vacuuming with heating, and tried to perform heating treatment under different vacuum degrees. It was found that when the vacuum degree is not higher than 2000Pa, the heating temperature is not lower than 100°C and does not exceed the thermal deformation temperature of the organic fiber core material, most of the water and gas on the surface and inside of the organic fiber core material are removed, and the thermal conductivity of the organic fiber core material is low. If the pretreated organic fiber core material is used to make a vacuum insulation board, the obtained vacuum insulation board has a low thermal conductivity and good insulation performance. In addition, when testing the thermal aging performance of the vacuum insulation board, it was found that after vacuum heating treatment, the thermal conductivity of the organic fiber core material deteriorated less and the long-term aging resistance was better. By analyzing the reasons, it can be seen that during the vacuum heating treatment stage, the organic fiber core material releases more adsorbed gas. After it is made into a vacuum insulation board, the amount of gas released by the organic fiber core material during the use of the vacuum insulation board is reduced, and the vacuum degree in the vacuum insulation board can be maintained stable for a longer time.

[0051] In order to further reduce the thermal conductivity of the vacuum insulation panel made of organic fiber core material, the inventor tried to optimize the thickness of the fibers in the organic fiber core material and the arrangement of the fibers. After countless attempts, he finally achieved a vacuum insulation panel with an organic fiber core material having a thermal conductivity of about 2mW / (m·K) by optimizing the organic fiber core material and combining it with vacuum heating treatment. The thermal insulation performance of the vacuum insulation panel with organic fiber as the core material can reach a level not lower than that of the vacuum insulation panel with glass fiber as the core material.

[0052] In some embodiments of the present invention, the present invention provides a method for pretreating an organic fiber core material, comprising the following steps: vacuum heating the organic fiber core material; in the vacuum heating step, the vacuum degree is not higher than 2000 Pa, and the heating temperature is 100-190° C. If the temperature is lower than 100° C., the effect of removing water and gas inside the organic fiber core material is poor, and if the temperature is higher than 190° C., most of the organic fiber core material will be crystallized and fail.

[0053] In some embodiments of the present invention, the vacuum degree is 1000-2000 Pa. In some embodiments, the vacuum degree is 1500-2000 Pa.

[0054] In some embodiments of the present invention, the heating temperature is 100-160°C; in some embodiments of the present invention, the heating temperature is 110-150°C.

[0055] In some embodiments of the present invention, the heating time in the vacuum heating treatment step is 0.5 to 5 hours. The longer the heating time, the better the effect of removing water and gas inside and on the surface of the organic fiber core material, and accordingly, the higher the production cost. Considering the cost and the effect of removing water and gas, in some embodiments of the present invention, the selected heating time is 0.5 to 5 hours.

[0056] In some embodiments of the present invention, the organic fiber core material is made by alternately stacking a first fiber layer and a second fiber layer; the angle between the fibers in the first fiber layer and the second fiber layer is 60° to 90°. In some embodiments of the present invention, the angle between the fibers in the first fiber layer and the second fiber layer is 80° to 90°. When the angle between the fibers in the first fiber layer and the second fiber layer is 80° to 90°, the fiber support effect between the two fiber layers is better, the structure is more stable, and it is less likely to collapse during vacuuming. The vacuum insulation panel has a lower thermal conductivity and better insulation performance.

[0057] In some embodiments of the present invention, the number of layers of the organic fiber core material is 160 to 200. In some embodiments of the present invention, the number of layers of the organic fiber core material is 170 to 190.

[0058] In some embodiments of the present invention, the diameter of the fibers in the first fiber layer is 4-30 μm; in some embodiments of the present invention, the diameter of the fibers in the first fiber layer is 10-20 μm.

[0059] In some embodiments of the present invention, the diameter of the fibers in the second fiber layer is 4-30 μm; in some embodiments of the present invention, the diameter of the fibers in the second fiber layer is 10-20 μm.

[0060] The organic fiber core material is prepared by orthogonally stacking fibers with a diameter of 4 to 30 μm. The fiber thickness in the organic fiber core material is appropriate and the structure is relatively stable. It can meet the requirements of not causing structural collapse during vacuuming and still retaining a high porosity and a relatively stable structural form.

[0061] In some embodiments of the present invention, the gram weight of the fibers in the first fiber layer is 10-40 g / m 2 In some embodiments of the present invention, the weight of the fibers in the first fiber layer is 10-30 g / m 2 In some embodiments of the present invention, the weight of the fibers in the first fiber layer is 10-25 g / m 2 .

[0062] In some embodiments of the present invention, the gram weight of the fibers in the second fiber layer is 10-40 g / m 2In some embodiments of the present invention, the weight of the fibers in the second fiber layer is 10-30 g / m 2 In some embodiments of the present invention, the weight of the fibers in the second fiber layer is 10-25 g / m 2 .

[0063] If the fiber weight is too large or too small, the weight and porosity of the organic fiber core material will not meet the requirements, so that the vacuum insulation panel produced will not meet the requirements of light weight and good insulation performance.

[0064] In some embodiments of the present invention, the material of the organic fiber core material is selected from at least one of polyester, polypropylene, polyethylene, polystyrene, butadiene, and styrene. Organic fibers of different materials are arranged according to the fiber thickness and fiber arrangement in some embodiments of the present invention, and the obtained organic fiber core material has a lower thermal conductivity and better thermal insulation performance after vacuum heating treatment.

[0065] In some embodiments of the present invention, another aspect of the present invention provides a vacuum insulation panel, comprising a barrier material and an organic fiber core material vacuum-sealed in the barrier material; the organic fiber core material is vacuum-heated before vacuum-sealing.

[0066] In some embodiments of the present invention, the thickness of the vacuum insulation panel is 8-9 mm.

[0067] In some embodiments of the present invention, the density of the vacuum insulation panel is 200-250 kg / m 3 .

[0068] In some embodiments of the present invention, the thermal conductivity of the vacuum insulation panel is 2-2.2 mW / (m·K).

[0069] In some embodiments of the present invention, the barrier material is selected from a double-sided aluminum film, a cation film, and a double-sided aluminum-free film. The barrier material in the present invention can be made in-house according to relevant techniques or can be a commercially available product.

[0070] In some embodiments of the present invention, the present invention further provides a method for preparing a vacuum insulation panel, comprising the following steps:

[0071] The organic fiber core material after vacuum heating treatment is vacuum sealed in a barrier material to obtain a vacuum insulation panel.

[0072] In some embodiments of the present invention, a method for preparing a vacuum insulation panel comprises the following steps: first, subjecting an organic fiber core material to vacuum heating treatment under conditions where the vacuum degree is not higher than 2000Pa and the heating temperature is 100 to 190°C; placing the pretreated organic fiber core material into a barrier bag made of a barrier material, evacuating the bag to a vacuum degree of 0.0005-1Pa for 10 to 120 minutes, and then sealing the bag.

[0073] In some embodiments of the present invention, a method for preparing a vacuum insulation panel comprises the following steps: firstly pretreating an organic fiber core material under conditions of a vacuum degree of 1500 to 2000 Pa and a heating temperature of 100 to 160°C, placing the pretreated organic fiber core material into a barrier bag made of a barrier material under a vacuum environment, evacuating the bag to a vacuum degree of 0.0005-1Pa, evacuating the bag for 10 to 120 minutes, and then sealing the bag.

[0074] In some embodiments of the present invention, a method for preparing a vacuum insulation panel comprises the following steps: firstly pretreating an organic fiber core material under conditions of a vacuum degree of 2000Pa and a heating temperature of 110 to 150°C, placing the pretreated organic fiber core material into a barrier bag made of a barrier material, evacuating the bag to a vacuum degree of 0.001 to 1Pa, and sealing the bag after evacuating the bag for 10 to 120 minutes.

[0075] In some embodiments of the present invention, the sealing step adopts heat pressure sealing, and a heat pressure sealing machine is used to seal the vacuumed barrier bag.

[0076] In some embodiments of the present invention, the preparation method of the vacuum insulation panel is as follows: Figure 1 As shown, the specific steps include: firstly vacuum-heating the organic fiber, drying the organic fiber core material and the membrane material after vacuum-heating respectively, then loading the getter, desiccant and organic fiber into the membrane material, evacuating, sealing and then heat-treating.

[0077] In some embodiments of the present invention, the heat treatment step is performed by heat pressing to roll the barrier material sealed with the organic fiber core material flat.

[0078] In some embodiments of the present invention, the present invention provides a refrigeration device, which uses the above-mentioned vacuum insulation panel as an insulation material.

[0079] In some embodiments of the present invention, the refrigeration device is a refrigerator.

[0080] In some embodiments of the present invention, the refrigeration device is a freezer.

[0081] In some embodiments of the present invention, the refrigeration equipment is a cold storage room.

[0082] In some embodiments of the present invention, the refrigeration equipment is a refrigerated transport vehicle.

[0083] These refrigerators, freezers, cold rooms, refrigerated transport vehicles and other refrigeration equipment have all the features and advantages of the vacuum insulation panels described above.

[0084] In some embodiments of the present invention, the vacuum insulation panel is used in ships as a thermal insulation material in the ships.

[0085] In some embodiments of the present invention, the vacuum insulation panel is applied in aviation equipment as a thermal insulation material in the aviation equipment.

[0086] In some embodiments of the present invention, the vacuum insulation panel is applied to building materials as a heat-insulating material in building materials.

[0087] These refrigerators, ships, aviation equipment or building materials have all the features and advantages of the vacuum insulation panels described above.

[0088] The present invention is further described in detail below by means of specific examples. Unless otherwise specified, the raw materials, reagents or devices used below can be obtained from conventional commercial sources. Unless otherwise specified, the experiments or test methods are conventional methods in the art.

[0089] Trilobal polyester fiber can be purchased from the following companies: Shanghai Jingfa Industrial Co., Ltd., Guangzhou Yihetai Nonwoven Fabric Co., Ltd., Guangzhou Yixian Nonwoven Fabric Co., Ltd. or Wenzhou Chaocheng Nonwoven Fabric Co., Ltd.

[0090] The preparation method of the organic fiber core material in Examples 1 to 2 and Comparative Example 1 is as follows: a fiber having a diameter of 13 microns and a gram weight of 18 g / m 2 The three-leaf polyester fiber is made into a roll material, which is placed on a stand and arranged manually or by a cloth-pulling machine. A single layer of cloth is spread on the platform according to a certain length and cut; the stand is turned 90 degrees, and the arrangement is controlled manually or by a cloth-pulling machine, and the second layer is spread and cut; the stand is turned 90 degrees, and the arrangement is controlled manually or by a cloth-pulling machine, and the third layer is spread and cut; and so on, when 180 layers are laid, an orthogonal stacked organic fiber core material sample is obtained, and the angle between the fibers in the organic fiber core material is 90°.

[0091] Example 1

[0092] Combination Figure 1 The preparation process flow chart in the figure illustrates the preparation method of the vacuum insulation panel in this example, which comprises the following steps:

[0093] (1) Vacuum heating treatment: the organic fiber core material is heated at a temperature of 110° C. and a vacuum degree of 2000 Pa for 1 h to obtain an organic fiber core material after vacuum heating treatment;

[0094] (2) Place the organic fiber core material in the cation membrane, evacuate for 60 minutes, and set the vacuum degree to 0.001 Pa. After vacuum packaging, the vacuum insulation panel in this example is obtained. The thickness of the vacuum insulation panel produced in this example is 8.2 mm, and the density is 220 kg / m 3 .

[0095] Example 2

[0096] The method for preparing the vacuum insulation panel in this example comprises the following steps:

[0097] (1) Vacuum heating treatment: the organic fiber core material is heated at a temperature of 110° C. and a vacuum degree of 2000 Pa for 0.5 h to obtain an organic fiber core material after vacuum heating treatment;

[0098] (2) Place the organic fiber core material in the cation membrane, evacuate for 60 minutes, and set the vacuum degree to 0.001 Pa. After vacuum packaging, the vacuum insulation panel in this example is obtained. The thickness of the vacuum insulation panel produced in this example is 8.2 mm, and the density is 220 kg / m 3 .

[0099] Comparative Example 1

[0100] The method for preparing the vacuum insulation panel in this example comprises the following steps:

[0101] (1) Heating pretreatment: heating the organic fiber core material at 150° C. under normal pressure for 1 h to obtain an organic fiber core material after heating pretreatment;

[0102] (2) Place the organic fiber core material in the cation membrane, evacuate for 60 minutes, and set the vacuum degree to 0.001 Pa. After vacuum packaging, the vacuum insulation panel in this example is obtained. The thickness of the vacuum insulation panel produced in this example is 8.2 mm, and the density is 220 kg / m 3 .

[0103] Performance Test:

[0104] (1) Thermal conductivity test

[0105] The double plate method was used to test the initial thermal conductivity of the vacuum insulation panels in Examples 1 to 2 and Comparative Example 1, respectively. The initial thermal conductivity is the thermal conductivity obtained by testing after the vacuum insulation panels were prepared. The specific test conditions are: the cold plate temperature is 5°C, the hot plate temperature is 35°C, the ambient temperature is 23°C, and the ambient humidity is 50%, and the initial thermal conductivity is measured; the vacuum insulation panels in Example 1 and Comparative Example 1 are placed in an environment of 70°C for 10 days for thermal aging, and then the thermal conductivity after thermal aging for 10 days is measured according to the above-mentioned test method for the initial thermal conductivity; the vacuum insulation panels in Examples 1 to 2 and Comparative Example 1 are placed in an environment of 70°C for 30 days for thermal aging, and then the thermal conductivity after thermal aging for 30 days is measured according to the above-mentioned test method for the initial thermal conductivity, and the results measured by the above-mentioned test method are recorded in Table 1 below.

[0106] Table 1 Thermal conductivity test results of vacuum insulation panels in Examples 1 to 2 and Comparative Example 1

[0107] Thermal conductivity (mW / (m·K)) Comparative Example 1 Example 1 Example 2 initial 2.16 2.01 2.10 70℃ / 10 days 3.09 2.86 / 70℃ / 30 days 3.52 2.98 3.35

[0108] It can be seen from Table 1 above that compared with Comparative Example 1, the heating temperature of Example 1 is reduced by 40°C, but the initial thermal conductivity of the vacuum insulation panel obtained is reduced by 0.15 mW / (m·K) compared with Comparative Example 1, and the thermal conductivity measured after 30 days of thermal aging at 70°C is reduced by 0.54 mW / (m·K); compared with Comparative Example 1, the heating temperature of Example 2 is reduced by 40°C, and the heating time is shortened to half, but the initial thermal conductivity of the vacuum insulation panel obtained is reduced by 0.06 mW / (m·K), and the thermal conductivity measured after 30 days of thermal aging at 70°C is reduced by 0.17 mW / (m·K); by comparison with Comparative Example 1, it is further shown that the vacuum heating treatment step can reduce the heating temperature and the initial thermal conductivity of the organic fiber core material, thereby improving the aging resistance of the organic fiber core material. Compared with Example 1, the heating time of Example 2 is shortened to half, and the initial thermal conductivity of the vacuum insulation panel obtained is 0.09 mW / (m·K) higher than that of Example 1. The thermal conductivity measured after 30 days of thermal aging at 70°C is increased by 0.37 mW / (m·K), indicating that increasing the heating time has a better effect on removing water and other gases inside the organic fiber core material.

[0109] At present, the thermal conductivity of vacuum insulation panels with organic fibers as core materials is generally high. The organic fiber core materials in Examples 1 and 2 are obtained by optimizing the fiber diameter and fiber arrangement to obtain organic fiber core materials with very low thermal conductivity. At this time, the thermal conductivity of the organic fiber core material is already very low, and various performances are close to the limits of organic fibers. It is difficult to further reduce the thermal conductivity of the organic fiber core material. Even reducing the thermal conductivity of the organic fiber core material by 0.01mW / (m·K) is a great challenge for technicians in this field. The inventors heat the organic fiber core material in a vacuum environment with a specific vacuum degree to reduce the thermal conductivity of the organic fiber core material by 0.06-0.2mW / (m·K), thereby achieving a thermal conductivity of about 2mW / (m·K) for the vacuum insulation panel with organic fiber as the core material, which meets the performance requirements of industry and commerce for vacuum insulation panels. In addition, the cost of organic fibers is greatly reduced compared to glass fibers, and organic fibers can be recycled after being discarded. They are less irritating to the human body during production, and are expected to replace the glass fiber core materials in existing vacuum insulation panels.

[0110] (2) Gas release test under low pressure

[0111] The organic fiber used in Example 1 was heated at 190°C (limit temperature) for 1 h under normal pressure, and the inorganic fiber, centrifugal cotton and short chopped filaments, were heated at 230°C for 1 h under normal pressure. Then, the organic fiber and inorganic fiber (centrifugal cotton and short chopped filaments) used in Example 1 were tested at 1×10 -4 The gas release under the vacuum degree of Pa, the test model is: HIDENHMTRC101; the test conditions are: the test range is 1~100m / z amu; the test temperature is 25℃, and the relative humidity is 40%; the specific test results are as follows Figure 2 As shown. Figure 2 It can be seen that the order of gas release is: organic fiber > chopped filaments > centrifugal cotton. It can be seen that after being heated at 190°C under normal pressure, the surface of organic fiber still adsorbs a lot of moisture and small molecular gases. Under low pressure, the amount of moisture and small molecular gases adsorbed inside the organic fiber is significantly higher than that of chopped filaments and centrifugal cotton inorganic fibers.

[0112] To solve this problem, the inventors pre-treated the organic fiber core with vacuum heating (heating temperature of 110°C, vacuum degree of 2000Pa, and treatment time of 1h) and normal pressure heating (heating temperature of 150°C, and treatment time of 1h), and then tested the organic fiber core after vacuum heating and normal pressure heating at 1×10 -4 The gas release under the vacuum degree of Pa, the specific test results are as follows Figure 3 As shown. Figure 3It can be seen that the order of gas release is: vacuum heating treatment < normal pressure heating treatment. It can be seen that the gas released by organic fiber under low pressure after vacuum heating treatment is significantly reduced, indicating that vacuum heating treatment can effectively remove the moisture, small molecule gas and large molecule gas adsorbed inside the organic fiber core material, so that the amount of gas released by the organic fiber core material under low pressure is reduced. After the organic fiber core material after vacuum heating treatment is used to make vacuum insulation panels, the amount of gas released by the organic fiber core material in the vacuum insulation panel can be reduced, the thermal conductivity of the vacuum insulation panel can be reduced, and the insulation performance can be improved. Then the thermal conductivity of the vacuum insulation panel made of organic fiber core material treated by vacuum heating and normal pressure heating is tested. Among them, the thermal conductivity of the vacuum insulation panel with organic fiber treated by normal pressure heating as the core material is 2.16mW / (m·K), while the thermal conductivity of the vacuum insulation panel with organic fiber treated by vacuum heating as the core material is reduced to 2.01mW / (m·K), which further shows that vacuum heating treatment can significantly improve the thermal conductivity of the vacuum insulation panel with organic fiber as the core material.

[0113] In summary, the above-mentioned vacuum insulation panel has good thermal insulation performance and heat aging resistance, and can be used in refrigeration equipment (for example: refrigerators, freezers, cold storage rooms, refrigerated transport vehicles), ships, aviation equipment or building materials, and used as a thermal insulation material to make refrigeration equipment, ships, aviation equipment or building materials have good thermal insulation, heat insulation and heat aging resistance.

[0114] In the description of this specification, the description with reference to the terms "some embodiments", "examples" or "specific embodiments" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0115] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for pretreating an organic fiber core material, characterized in that: The following steps are involved: The organic fiber core material is subjected to vacuum heating treatment; in the vacuum heating treatment step, the vacuum degree is not higher than 2000 Pa, and the heating temperature is not lower than 100° C. and does not exceed the thermal deformation temperature of the organic fiber core material.

2. The method for pretreating organic fiber core material according to claim 1, characterized in that: The heating temperature is 100-190°C.

3. The method for pretreating an organic fiber core material according to claim 1 or 2, characterized in that: The heating time in the vacuum heating treatment step is 0.5 to 5 hours.

4. The method for pretreating organic fiber core material according to claim 1, characterized in that: The vacuum degree is 1000-2000Pa.

5. The method for pretreating organic fiber core material according to claim 1, characterized in that: The organic fiber core material is made by alternately stacking a first fiber layer and a second fiber layer; the angle between the fibers in the first fiber layer and the second fiber layer is 60° to 90°.

6. The method for pretreating organic fiber core material according to claim 5, characterized in that: The number of layers of the organic fiber core material is 160-200.

7. The method for pretreating organic fiber core material according to claim 5, characterized in that: The diameters of the fibers in the first fiber layer and the second fiber layer are independently 4 to 30 μm.

8. The method for pretreating organic fiber core material according to claim 5, characterized in that: The weight of the fibers in the first fiber layer and the second fiber layer is independently 10-40 g / m 2 .

9. The method for pretreating an organic fiber core material according to claim 1, characterized in that: The material of the organic fiber core material is selected from at least one of polyester, polypropylene, polyethylene, polystyrene, butadiene and styrene.

10. A vacuum insulation panel, characterized in that: It comprises a barrier material and an organic fiber core material vacuum-sealed in the barrier material; the organic fiber core material is an organic fiber core material obtained by the pretreatment method according to any one of claims 1 to 9.

11. The vacuum insulation panel according to claim 10, characterized in that: The barrier material is selected from a double-sided aluminized film, a yin-yang film, and a double-sided aluminum-free film.

12. The vacuum insulation panel according to claim 10, characterized in that: The thickness of the vacuum insulation panel is 8-9 mm.

13. The vacuum insulation panel according to claim 10, characterized in that: The density of the vacuum insulation panel is 200-250 kg / m 3 .

14. The vacuum insulation panel according to claim 10, characterized in that: The thermal conductivity of the vacuum insulation panel is 1.9 to 2.2 mW / (m·K).

15. The method for preparing the vacuum insulation panel according to any one of claims 10 to 14, characterized in that: The following steps are involved: The pretreated organic fiber core material is vacuum-sealed in the barrier material to obtain the vacuum insulation panel.

16. The method for preparing the vacuum insulation panel according to claim 15, characterized in that: The preparation method comprises the following steps: The pretreated organic fiber core material is placed in a barrier bag made of barrier material, evacuated to a vacuum degree of 0.0005-1Pa, and sealed.

17. The method for preparing the vacuum insulation panel according to claim 16, characterized in that: The vacuuming time is 10 to 120 minutes.

18. The method for preparing the vacuum insulation panel according to claim 16, characterized in that: The preparation method further comprises a step of performing heat treatment after the sealing step.

19. A refrigeration device, characterized in that: The vacuum insulation panel comprises the vacuum insulation panel according to any one of claims 10 to 14.

20. Use of the vacuum insulation panel according to any one of claims 10 to 14 in refrigerators, ships, aviation equipment or building materials.

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