Core material for heat preservation, preparation method and vacuum heat preservation material of core material

Abstract

The invention provides a heat preservation core material which is of a structure comprising a bottom, a middle supporting layer and a surface layer, specifically, the middle supporting layer is of a perforated supporting plate structure filled with a loose powder mixture, and the surface and the bottom are arranged to be the loose powder mixture or surface felts. Meanwhile, the invention also provides a preparation method of the core material and the vacuum thermal insulation material, the prior art of taking the conventional glass fiber or inorganic powder as the core material is changed in a breakthrough manner for the first time, the compressive strength of the vacuum thermal insulation material under the core material with the structure can be 0.1-10MPa, the density of the core material is less than or equal to 150kg / m < 3 >, and the vacuum thermal insulation material has good thermal insulation performance. Due to the low density, the weight of the thermal insulation material is much lighter than that of the conventional thermal insulation material with the density of 170-600kg / m < 3 >, and the application range of the thermal insulation material during construction is expanded.

Description

Technical Field

[0001] The invention belongs to the technical field of vacuum thermal insulation materials, and in particular relates to a thermal insulation core material, a preparation method and a vacuum thermal insulation material thereof. Background Art

[0002] Vacuum insulation panels are panels formed by placing core materials with good thermal insulation performance into an air-insulating structure, vacuuming it, and then sealing it. Currently, vacuum insulation panels have been widely used in refrigerators, freezers, cold storages, refrigerated trucks, refrigerated containers, wall insulation, and other fields. For insulation materials, lightweight insulation materials will be the technical development trend in this field, but the current vacuum insulation panels have high density, generally requiring a density of (please add) and compressive strength of (please add). Such performance limits the scope of its use, and there are still many technical difficulties to overcome in the technology of lightweight insulation materials. Summary of the invention

[0003] Technical solution: In order to solve the above-mentioned technical problems, the present invention provides a core material for thermal insulation, which specifically includes a bottom mixed layer, a supporting reinforcement layer, and a surface mixed layer; the bottom mixed layer is a loose powder mixture or a surface felt with a thickness of d1, the supporting reinforcement layer is a supporting plate filled with the loose powder mixture, and the surface mixed layer is a loose powder mixture or a surface felt with a thickness of d2; wherein the loose powder mixture is a mixture of silicon dioxide, silicon carbide, ferrosoferric oxide, glass fiber, high silica fiber, and polyester fiber; the surface felt is glass fiber cotton felt, high silica fiber or polyester fiber felt; and 0.5mm<d1<30%d, 0.5mm<d2<30%d, d is the thickness of the core material.

[0004] As an improvement, the support plate is a honeycomb plate, which is a flat plate with closely arranged honeycomb cells, and the honeycomb cells are filled with a loose powder mixture; or it is a special-shaped flat plate with holes inside, and the holes are filled with a loose powder mixture, and the shape of the holes is honeycomb, quadrilateral, pentagon, triangle or irregular; or it is a spherical crown plate, and the concave part is filled with a loose powder mixture.

[0005] As an improvement, the diameter of the glass fiber, high silica fiber and polyester fiber mixture is ≤6 μm, and the length is ≤6 mm.

[0006] As a specific embodiment of the present invention, a core material of a combination of the above-mentioned thermal insulation core materials is also provided, specifically, at least one of the above-mentioned thermal insulation core materials is stacked to obtain a multi-layer core material combination for use.

[0007] As an improvement, a non-woven fabric is also included to independently wrap the outer surface of the above-mentioned thermal insulation core material.

[0008] As a specific embodiment of the present invention, a method for preparing a thermal insulation core material is also provided, wherein the thermal insulation core material is the thermal insulation core material described above, and the specific steps are as follows:

[0009] First, place a groove mold of a certain size, and place a loose powder mixture or surface felt with a thickness of d1 at the bottom of the mold;

[0010] Then, a support plate is placed on the bottom mixed material layer, and the filling is stopped when the loose powder mixture is continuously filled and a surface mixed material layer with a thickness of d2 is obtained after overflowing the support plate;

[0011] Finally, pressing is performed to obtain a molded core material with a thickness of d.

[0012] As a specific embodiment of the present invention, a vacuum insulation material is also provided, including a film material and a core material, wherein the core material is any of the insulation core materials described above; wherein the insulation material is a vacuum insulation material that is prepared by wrapping the film material around the outer surface of the core material and performing a vacuum treatment between the core material and the film material.

[0013] As an improvement, the compressive strength of the vacuum insulation material is 0.1-10MPa, and the density of the core material is ≤150kg / m 3 ; The film material is an aluminum film barrier film or an EV film material, and the thickness of the film material is 15-120μm.

[0014] Beneficial effect: Compared with the conventional ones, the core material of the present invention adopts a structure of a bottom, an intermediate support layer and a surface layer. Specifically, the intermediate support layer is an open-hole support plate structure filled with a loose powder mixture, and the surface and the bottom are set as a loose powder mixture or a surface felt. The original structure has for the first time changed the existing technology of conventional glass fiber or inorganic powder as a core material, and can achieve a compressive strength of 0.1-10MPa and a core material density of ≤150kg / m 3 Such low density can make the weight of the insulation material lower than the density of existing conventional insulation materials of 170-600kg / m 3 It is much lighter, which expands the application scope of thermal insulation materials in construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of the support plate whose core material is honeycomb according to the present invention.

[0016] Figure 2 The schematic diagram of the core material structure of the honeycomb structure of the present invention.

[0017] Figure 3 It is a schematic diagram of the process of preparing the core material of the honeycomb structure according to the present invention.

[0018] Figure 4It is a schematic diagram of the structure of the heat-insulating core material with a special-shaped structure of the present invention.

[0019] Figure 5 This is a schematic diagram of the structure of the thermal insulation material prepared by stacking multiple thermal insulation core materials according to the present invention.

[0020] Figure 6 The figure is a schematic diagram of the structure of a thermal insulation material prepared from a thermal insulation core material according to the present invention.

[0021] In the figure: bottom mixed layer 1, support and reinforcement layer 2, surface mixed layer 3, membrane material 4, non-woven fabric 5, and mold 6. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be described clearly and completely below so that those skilled in the art can better understand the advantages and features of the present invention, thereby making a clearer definition of the protection scope of the present invention. The embodiments described in the present invention are only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0023] See Figure 2 As shown, a core material for thermal insulation includes, from bottom to top, a bottom mixed material layer 1, a supporting and reinforcing layer 2, and a surface mixed material layer 3.

[0024] See Figure 1 As shown, in the present invention, the supporting reinforcement layer 2 of the core material includes a supporting plate, the bottom mixed layer 1 is a loose powder mixture or surface felt with a thickness of d1, and the surface mixed layer 3 is a loose powder mixture or surface felt with a thickness of d2.

[0025] In the present invention, the loose powder mixture is a mixture of silicon dioxide, silicon carbide, ferroferric oxide, glass fiber, high silica fiber and polyester fiber.

[0026] In the present invention, the diameter of the loose powder mixture of glass fiber, high silica fiber and polyester fiber filled in the core material is ≤6μm, and the length is ≤6mm. This setting is used to achieve that it can be filled without gaps during filling. If it is too long or the diameter is too large, it is easy to have problems of incomplete filling and large gaps during filling.

[0027] The surface felt is glass fiber cotton felt, high silica fiber or polyester fiber felt; in the present invention, the surface felt can be selectively placed on the bottom mixture layer 1 or the surface mixture layer 3 to protect the loose powder mixture from leaking out. Even if it falls, it will be concentrated on the surface felt.

[0028] In the present invention, the thickness is set to 0.5mm<d1<30%d, 0.5mm<d2<30%d, d is the core material thickness. Such thickness can achieve good supporting effect of the middle supporting reinforcement layer 2, and cooperate with the bottom surface and the surface to make the whole core material low in density and high in compressive strength.

[0029] In the present invention, optionally, the support plate is a honeycomb plate, which is a flat plate with closely arranged honeycomb cells, and the honeycomb cells are filled with a loose powder mixture; or it is a special-shaped flat plate with internal holes, and the holes are filled with a loose powder mixture, and the shape of the holes is honeycomb, quadrilateral, pentagon, triangle or irregular; or it is a spherical crown plate, and the concave part is filled with a loose powder mixture.

[0030] Example 1

[0031] See Figure 1 As shown, the support plate is a honeycomb structure vertical plate, which is a flat plate structure with honeycomb cells 21 tightly arranged, and the cells 21 are filled with loose powder mixture 22. Figure 3 As shown, the specific steps of the present invention in preparing the core material are: first, a groove mold 6 of a certain size is placed, and a loose powder mixture or surface felt with a thickness of d1 is placed at the bottom of the mold; then, a support plate is placed on the bottom mixture layer, and the loose powder mixture is continued to be filled, and when a surface mixture layer with a thickness of d2 is obtained after overflowing the support plate, the filling is stopped; finally, pressing is performed to obtain a molded core material with a thickness of d.

[0032] The support plate can be selected as a honeycomb structure support plate. The specific structure and preparation process are shown in Figure 1-3 shown.

[0033] Example 2

[0034] The present invention also provides a heat-insulating core material with a special-shaped structure, which is used to obtain core materials and vacuum heat-insulating materials with special shapes, so that the heat-insulating material can be used to insulate the end surface of the ellipsoidal water heater.

[0035] See Figure 4 The specific structure shown is: including a bottom mixed material layer 1, a support and reinforcement layer 2, and a surface mixed material layer 3. When preparing a special-shaped core material, the specific steps are: first, place a surface felt with a hole in the middle as the bottom mixed material layer 1; then place a support plate with a matching shape on the bottom mixed material layer as the support and reinforcement layer 2; then fill the loose powder mixture until the surface mixed material layer 3 with a thickness of d2 protrudes after the support and reinforcement layer 2 is filled, press to obtain a shaped core material, wrap it in a membrane material, and vacuumize it to obtain a vacuum insulation material with a special-shaped structure with a hole in the middle.

[0036] Example 3

[0037] In the present invention, the above-mentioned multiple core materials are wrapped by the structure of non-woven fabric 5, and stacked to obtain a combined heat-insulating core material. Figure 5 As shown, preferably, the number of the thermal insulation core materials is selected to be 2-10, and the thickness is selected according to the actual production needs.

[0038] Example 4

[0039] The loose powder mixture in the present invention can preferably be a mixture of silicon dioxide, silicon carbide, ferroferric oxide, and glass fiber, or a mixture of silicon dioxide, silicon carbide, ferroferric oxide, high silica fiber, and polyester fiber, or a mixture of silicon carbide, ferroferric oxide, glass fiber, or a mixture of silicon dioxide, ferroferric oxide, high silica fiber, and polyester fiber.

[0040] Example 4

[0041] In the present invention, different support plates are selected to prepare core materials in the manner of Examples 1-2. Figure 6 As shown, in the present invention, the core material is placed in the film material 4 and subjected to vacuum treatment to obtain a vacuum thermal insulation material, wherein the film material is an aluminum film barrier film.

[0042] The aluminum film barrier film is a composite film of multi-layer film materials, which are arranged in sequence as PA / PE / VMPET / Al / PE. In the present application, the thickness of the composite film material is set as PA film 10-25μm, the first layer PE film 1-5μm, VMPET film 5-18μm, Al film 1-10μm, and the second layer PE 40-65μm.

[0043] As other embodiments of the present invention, the film material can also be an EV film material, wherein the EV film material is sequentially arranged as PA / MPET / MPET / EVOH / PA / PE. In the present application, the thickness of the composite film material is set as the first layer PA film 10-25μm, the first layer MPET film 8-15μm, the second layer MPET film 5-18μm, the EVOH film 8-14μm, the second layer PA film 1-10μm, and the PE film 40-65μm.

[0044] In order to better introduce the structure of the core material in the present invention and its influence on the performance of the obtained vacuum thermal insulation material, the present invention conducts performance test experiments by setting different loose powder mixtures or surface felts, and others.

[0045] (1) The experimental group selected a filling powder mixture of silicon dioxide, silicon carbide, ferroferric oxide, glass fiber, high silica fiber, and polyester fiber, and obtained a core material by setting the supporting reinforcement layer as a honeycomb structure board in the manner of Example 2.

[0046] The control group has a core material and a filling powder mixture of silicon dioxide, silicon carbide, ferroferric oxide, glass fiber, high silica fiber, and polyester fiber.

[0047] The experimental group and the control group were subjected to weight or density performance test experiments respectively.

[0048] Table 1 Test data of core material density under different structures

[0049]

[0050] As shown in Table 1, in test groups 1-5, by adding honeycomb panels and pressing the surface felt, the density of the core material can be ≤150kg / m 3 .

[0051] Table 2 Test data without adding honeycomb panel core material density

[0052] Serial number Honeycomb Panel Surface Felt suppress <![CDATA[Core material density / kg·m 3 > Control group 1 none none have 182 Control group 2 none none have 175 Control group 3 none none have 180

[0053] From Table 2, it can be seen that in the control groups 1-3, no honeycomb panels and no surface felts were set, and only pressing was performed, and the density of the core material can be much greater than 150kg / m 3 .

[0054] (2) The core materials of the test group and the control group were prepared into vacuum insulation materials and their corresponding compressive strengths were measured.

[0055] Table 3 Test data of compressive strength of honeycomb core materials with different thicknesses

[0056] Serial number Honeycomb Panel Core material compressive strength / KPa 1 have 400 2 have 800 3 have 500 4 none 50 5 none 10

[0057] It can be seen from Table 3 that the compressive strength of the above test groups 1-4 is between 400-800 KPa, but it is found that the quality of the honeycomb panel affects the compressive strength. After selecting honeycomb panels of different qualities, the compressive strength will be different. However, after adding the honeycomb panel in this application, the compressive strength of the entire core material can be achieved in the range of 0.1-10 MPa, which is much greater than the compressive strength of the existing core material.

[0058] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A core material for thermal insulation, characterized in that: It includes a bottom mixed layer, a supporting and reinforcing layer, and a surface mixed layer; the bottom mixed layer is a loose powder mixture or a surface felt with a thickness of d1, the supporting and reinforcing layer is a supporting plate filled with the loose powder mixture, and the surface mixed layer is a loose powder mixture or a surface felt with a thickness of d2; the loose powder mixture is a mixture of two or more of silicon dioxide, silicon carbide, ferrosoferric oxide, glass fiber, high silica fiber, and polyester fiber; the surface felt is glass fiber cotton felt, high silica fiber or polyester fiber felt; and 0.5mm<d1<30%d, 0.5mm<d2<30%d, d is the thickness of the core material.

2. The thermal insulation core material according to claim 1, characterized in that: The support plate is a honeycomb plate, which is a flat plate with closely arranged honeycomb cells, and the honeycomb cells are filled with a loose powder mixture; or it is a special-shaped flat plate with holes inside, and the holes are filled with a loose powder mixture, and the shape of the holes is honeycomb, quadrilateral, pentagon, triangle or irregular; or it is a spherical crown plate, and the concave part is filled with a loose powder mixture.

3. The thermal insulation core material according to claim 1, characterized in that: The diameters of the glass fibers, high-silica fibers and polyester fiber mixtures are all ≤6 μm, and the lengths are all ≤6 mm.

4. A combined thermal insulation core material, characterized in that: At least one thermal insulation core material according to any one of claims 1 to 3 is stacked into multiple layers to form a core material.

5. The thermal insulation core material according to claim 4, characterized in that: It also includes non-woven fabric, which independently wraps the outer surface of the thermal insulation core material according to any one of claims 1-3.

6. A method for preparing a core material for thermal insulation, characterized in that: The thermal insulation core material is the thermal insulation core material according to any one of claims 1 to 5, and the specific steps are: First, a groove mold of a certain size is placed, and a loose powder mixture or surface felt with a thickness of d1 is placed at the bottom of the mold; then, a support plate is placed on the bottom mixed material layer, and the filling is stopped when the loose powder mixture is continuously filled and a surface mixed material layer with a thickness of d2 is obtained after overflowing the support plate; Finally, pressing is performed to obtain a molded core material with a thickness of d.

7. A vacuum thermal insulation material, characterized in that: It comprises a film material and a core material, wherein the core material is the thermal insulation core material according to any one of claims 1 to 5; The heat-insulating material is a vacuum heat-insulating material in which a film material is wrapped around the outer surface of a core material and a vacuum treatment is performed between the core material and the film material.

8. The vacuum thermal insulation material according to claim 7, characterized in that: The compressive strength of the vacuum insulation material is 0.1-10MPa, and the density of the core material is ≤150kg / m 3 ; The film material is an aluminum film barrier film or an EV film material, and the thickness of the film material is 15-120μm.

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