Insulating plate manufacturing method and insulating plate

Abstract

The invention discloses an insulating plate manufacturing method which comprises the steps of surface plate preparation, corrugated plate preparation, base plate compounding and insulating plate forming: in the base plate compounding step, a surface plate, a polyurethane foaming material and a corrugated plate are flatly paved in sequence from bottom to top, mould pressing curing is performed under the heating condition to obtain a semi-finished base plate, and a plurality of clamping grooves are formed; in the insulating plate forming step, a base plate, a polyurethane foaming material, a corrugated plate, another polyurethane foaming material and another base plate are sequentially laid from bottom to top, during laying, the face, with the protruding parts, of the lower-layer base plate faces upwards, the face, with the protruding parts, of the upper-layer base plate faces downwards, and the protruding parts on the middle-layer corrugated plate are clamped into clamping grooves in the upper-layer base plate and the lower-layer base plate. And performing mold-pressing curing under a heating condition to obtain the insulating plate. The insulating plate provided by the invention has excellent heat resistance, heat insulation property and electrical insulation property, and is not easy to crack and break during further machining. The invention correspondingly provides the insulating plate prepared by the method.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal insulation materials, and particularly relates to a method for manufacturing an insulating board and an insulating board. Background Art

[0002] Referring to Figure 1 , an insulating board with a typical structure includes a pair of outer panel layers 1 and an inner insulating core 2 sandwiched between the outer panel layers 1. The outer panel layer 1 can be a glass fiber felt impregnated with resin, and the inner insulating core 2 can be a polyurethane foam layer. The insulating board with such a structure usually has good heat resistance, heat insulation and electrical insulation properties. However, the internal bonding strength is relatively low when glass fiber combines with other materials, and the adhesion between the polyurethane foam and other materials is also easily affected by temperature changes, resulting in peeling between the inner insulating core and the outer panel layer. At the same time, for installation needs, it is necessary to cut tenon grooves / drill holes in the insulating board. The tenon grooves / drilled holes of the foregoing insulating board are easily peeled off by shear force, resulting in cracking of the tenon groove openings / installed hole walls, affecting the practicability of the insulating board. Therefore, it is necessary to provide an insulating board that is not easily separated and delaminated and not easily cracked. Summary of the Invention

[0003] To solve the foregoing problems, the present invention provides a method for manufacturing an insulating board and an insulating board.

[0004] In the first aspect, a method for manufacturing an insulating board according to the present invention specifically provides the following technical solutions:

[0005] A method for manufacturing an insulating board includes the following steps:

[0006] Preparation of a flat board: After impregnating a fiber felt with a first thermosetting resin, hot-press and cure it to obtain a flat board;

[0007] Preparation of a corrugated board: After impregnating a fiber felt with a second thermosetting resin, hot-press and cure it to obtain a corrugated board; the cross-section of the corrugated board is in a corrugated shape, forming a plurality of parallel strip-shaped raised portions and recessed portions;

[0008] Lamination of a substrate: In a mold, lay a flat board obtained in the flat board preparation step, a layer of polyurethane foam material, and a corrugated board obtained in the corrugated board preparation step in sequence from bottom to top, and hot-press and cure it under heating conditions to obtain a semi-finished substrate; open a plurality of mounting grooves distributed in a rectangular array on the semi-finished substrate, the distance between adjacent two columns of mounting grooves is equal to the distance between adjacent two raised portions, and the mounting grooves on the same raised portion are equally spaced, to obtain a substrate;

[0009] Insulating board forming: In the mold, lay a substrate layer, a layer of polyurethane foam, a corrugated board layer, a layer of polyurethane foam, and another substrate layer in sequence from bottom to top. When laying, the side with the raised part of the lower substrate faces upward, the side with the raised part of the upper substrate faces downward, and the raised part on the middle corrugated board is snapped into the snap-in grooves on the upper and lower substrates. Then, it is molded and cured under heating conditions to obtain the insulating board.

[0010] By adopting the above scheme, the obtained insulating board includes a pair of flat plates, three corrugated board layers sandwiched between the two flat plates, and a polyurethane foam material layer filled in the gaps between the board layers. The insulating board as a whole has excellent heat resistance, heat insulation, and electrical insulation properties. At the same time, due to the snap-in grooves provided on the substrate, the three corrugated board layers are staggered and snap-embedded with each other, improving the overall anti-peeling and delamination resistance of the insulating board, and the stress applied to the insulating board can be evenly dispersed, and it is not easy to crack or break during machining.

[0011] Further, the first thermosetting resin and / or the second thermosetting resin is selected from any one of epoxy resin, phenolic resin, melamine formaldehyde resin, furan resin, polyurethane, and polyimide resin.

[0012] Further, the thicknesses of the flat plate and the corrugated board can be the same or different.

[0013] Further, the thickness of the flat plate and / or the corrugated board is 0.5 - 1 mm.

[0014] Further, the depth of the snap-in groove is 1 / 3 to 2 / 3 of the height of the raised part. The height of the raised part refers to the height difference between the wave crest and the wave trough of the corrugated board with a corrugated cross-section. If the depth of the snap-in groove is too shallow or too deep, it is not conducive to improving the anti-peeling and anti-cracking effects between layers.

[0015] Further, the height of the raised part is 2 - 4 mm, and the thickness of the insulating board is 5 - 10 mm.

[0016] Further, the fiber felt is a glass fiber felt or a PTFE needle punched felt. When using a PTFE needle punched felt as the fiber felt, before impregnating with the resin, the PTFE needle punched felt needs to be treated with naphthalene sodium to improve its internal bonding strength with the resin material.

[0017] Further, the thickness of the fiber felt is 50 - 180 μm, and the gram weight is 80 - 300 g / m 2 。

[0018] Further, before the insulating board forming step, the corrugated surface of the substrate and / or the corrugated board is subjected to corona treatment. After corona treatment, the bonding strength between the layers of the obtained insulating board is higher, and it is not easy to peel and delaminate.

[0019] In a second aspect, the present invention provides an insulating board prepared by the aforementioned method, which has excellent high-temperature resistance, heat insulation, and electrical insulation properties, and is not prone to cracking or delamination during tenoning / grooving or drilling processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of the insulating board in the background art;

[0021] Figure 2 is a schematic structural diagram of the corrugated board in the embodiment Figure 1 ;

[0022] Figure 3 is a schematic structural diagram of the corrugated board in the embodiment Figure 2 ;

[0023] Figure 4 is a working condition diagram of the substrate composite step in the embodiment;

[0024] Figure 5 is a schematic structural diagram of the substrate in the embodiment Figure 1 ;

[0025] Figure 6 is a schematic structural diagram of the substrate in the embodiment Figure 2 ;

[0026] Figure 7 is a working condition diagram of the insulating board forming step in the embodiment;

[0027] Figure 8 is a schematic structural diagram of the insulating board in the embodiment Figure 1 ;

[0028] Figure 9 is a schematic structural diagram of the substrate and the corrugated board in the embodiment;

[0029] Figure 10 is a schematic structural diagram of the insulating board in the embodiment Figure 2 .

[0030] DESCRIPTION OF REFERENCE NUMERALS:

[0031] 1, outer panel layer; 2, inner insulating core; 3, flat panel; 4, corrugated board; 41, raised portion; 42, recessed portion; 43, clamping groove; 5, substrate; 6, polyurethane foam; 7, mold; 8, insulating board; 81, mounting hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the following will further describe the present application in detail with reference to the accompanying drawings.

[0033] The present application provides a method for manufacturing an insulating board, including the following steps:

[0034] Preparation of flat plate: After impregnating a fiber mat with a first thermosetting resin, it is hot-pressed and cured to obtain a flat plate 3 with a thickness of 0.5 - 1 mm.

[0035] Preparation of corrugated plate: Referring to Figure 2 and Figure 3 , after impregnating a fiber mat with a second thermosetting resin, it is hot-pressed and cured to obtain a corrugated plate 4 with a thickness (h) of 0.5 - 1 mm; the cross-section of the corrugated plate 4 is in a corrugated shape, forming a number of parallel strip-shaped raised portions 41 and recessed portions 42, and the height (H) of the raised portions 41 is 2 - 4 mm.

[0036] Both the first thermosetting resin / second thermosetting resin can be selected from any one of epoxy resin, phenolic resin, melamine formaldehyde resin, furan resin, polyurethane and polyimide resin. The fiber mat is a glass fiber mat or a PTFE needle-punched mat treated with naphthalene sodium. The thickness of the fiber mat is 50 - 180 μm, and the gram weight is 80 - 300 g / m 2 , such as 2112 fiberglass cloth, 2119 fiberglass cloth, 106 fiberglass cloth, 1078 fiberglass cloth, 1086 fiberglass cloth, etc., and the specific specifications are selected according to actual needs.

[0037] The hot pressing in the "preparation of flat plate" step and the "preparation of corrugated plate" step has similarities, and the purpose is to cure and form. The difference is that the hot pressing mold 7 used in the latter has a wavy forming surface. Specifically, the hot pressing temperature depends on the type of resin selected. Taking epoxy resin as an example, it can be hot-pressed at 110 - 150 °C for 0.5 - 1 h. For the convenience of explanation, in the following examples, the first thermosetting resin and the second thermosetting resin selected are both epoxy resin compositions, which are composed of 0.01 - 5 wt% accelerator (2-ethyl-methylimidazole), 0.01 - 0.5 wt% catalyst (triphenylphosphine) and the balance of TU872SKL epoxy resin; in the "preparation of flat plate" step and the "preparation of corrugated plate" step, it is first heated to 120 ± 5 °C and hot-pressed for 15 - 30 min, then heated to 140 ± 5 °C and hot-pressed for 15 - 30 min, and after natural cooling to room temperature, other processings are carried out.

[0038] Lamination of the substrate: Referring to Figure 4 , Figure 5 and Figure 6, within the mold 7, layering in sequence from bottom to top a flat plate 3 obtained from the flat plate preparation step, a layer of polyurethane foam 6, and a corrugated plate 4 obtained from the corrugated plate preparation step, and curing by molding at 130°C and 2 - 5 MPa for 0.5 h to obtain a semi-finished substrate; then, on the semi-finished substrate, a number of card slots 43 distributed in a rectangular array are opened, which are for the raised portions 41 to be snapped into during the subsequent insulating plate forming step. The depth of the card slot 43 (the distance from the highest point of the raised portion 41 to the lowest point of the card slot 43, denoted as α) is 1 / 3 - 2 / 3 of the height (H) of the raised portion 41; the spacing between adjacent two columns of card slots 43 is equal to the spacing (L) between adjacent two raised portions 41, and the card slots 43 on the same raised portion 41 are equally spaced, thus obtaining the substrate 5.

[0039] Insulating plate forming: Refer to Figure 7 , Figure 8 and Figure 9 , within the mold 7, layering in sequence from bottom to top a layer of substrate 5, a layer of polyurethane foam 6, a layer of corrugated plate 4, a layer of polyurethane foam 6, and another layer of substrate 5. When laying, the side with the raised portion 41 of the lower substrate 5 faces upward, the side with the raised portion 41 of the upper substrate 5 faces downward, and the raised portions 41 on the middle corrugated plate 4 are snapped into the card slots 43 on the upper and lower substrates 5. Curing by molding at 130°C and 2 - 5 MPa for 0.5 h to obtain an insulating plate 8 with a thickness of 5 - 10 mm. The total thickness of the insulating plate 8 can be adjusted by the filling amount of the polyurethane foam 6 and the opening depth of the card slots 43.

[0040] [Examples 1 - 3]

[0041] The process steps of Examples 1 - 3 are basically the same, the differences are: different types, specifications, dimensions, etc. of the fiber mats, as shown in Table 1 for details.

[0042] Table 1. Material Specifications of Examples 1 - 3

[0043]

[0044] The polyurethane foam used in Examples 1 - 3 is prepared through the following steps:

[0045] Weigh 100 parts by weight of polyether, 7 parts by weight of silicone oil, 2.5 parts by weight of triethanolamine, and 3 parts by weight of water, and pour them into cup A in sequence, then stir evenly with an electric stirrer; pour 150 parts by weight of polymethylene polyphenyl isocyanate and 120 parts by weight of titanium dioxide into cup B in sequence, and stir thoroughly with an electric stirrer; then pour the materials in cup B into cup A, and stir evenly with an electric stirrer until evenly foamed to obtain the polyurethane foam. During the process of preparing the insulating plate, the polyurethane foam is prepared and used immediately.

[0046] [Examples 4 - 7]

[0047] Examples 4-7 are all based on Example 3, with the difference being that the height of the raised portion and the depth of the mounting groove are different, as shown in Table 2 for details.

[0048] Table 2. Material specifications of Examples 4-7

[0049]

[0050] [Example 8]

[0051] Example 8 is based on Example 7, except that polytetrafluoroethylene fiber felt is used instead of 2119 glass fiber cloth and 1086 glass fiber cloth. The polytetrafluoroethylene fiber felt has a gram weight of 300 g / m 2 , thickness 180 μm, and treated with sodium naphthalene. Before the insulating board forming step, the corrugated surface of the substrate and the corrugated board are subjected to corona treatment, and the corona treatment power is 30 kW.

[0052] [Example 9]

[0053] Example 9 is based on Example 7, except that the preparation method of the polyurethane foam material is different. Specifically, the preparation steps of the polyurethane foam material are as follows:

[0054] Weigh 100 parts by weight of polyether, 7 parts by weight of silicone oil, 2.5 parts by weight of triethanolamine and 3 parts by weight of water into a cup and stir evenly with an electric stirrer; add 150 parts by weight of polymethylene polyisocyanate, 120 parts by weight of titanium dioxide, 30 parts by weight of ZOLTEK TM PX35 chopped fibers (length 3 mm, diameter 7.2 μm) were poured into cup B in sequence and stirred thoroughly with an electric stirrer; then the material in cup B was poured into cup A and stirred evenly with an electric stirrer until uniform foaming occurred to obtain a polyurethane foam material.

[0055] [Example 10]

[0056] Example 10 is based on Example 8, except that the preparation method of the polyurethane foam material is different. Specifically, the preparation steps of the polyurethane foam material are as follows:

[0057] Weigh 100 parts by weight of polyether, 7 parts by weight of silicone oil, 2.5 parts by weight of triethanolamine and 3 parts by weight of water into a cup and stir evenly with an electric stirrer; add 150 parts by weight of polymethylene polyisocyanate, 120 parts by weight of titanium dioxide, 30 parts by weight of ZOLTEK TM PX35 chopped fibers (length 3 mm, diameter 7.2 μm) were poured into cup B in sequence and stirred thoroughly with an electric stirrer; then the material in cup B was poured into cup A and stirred evenly with an electric stirrer until uniform foaming occurred to obtain a polyurethane foam material.

[0058] [Application Examples]

[0059] An insulating board, with reference to Figure 10 , is obtained by cutting and drilling the insulating board prepared in any one of Examples 1-10. It is in a sector-annular shape, and a number of mounting holes 81 are spaced along the inner and outer arc-shaped edges for passing through connecting members such as bolts.

[0060] [Performance Test]

[0061] The insulating boards prepared in Examples 1-10 were respectively cut into specimens of 300mm * 300mm. A numerical control grooving machine was used to groove the side edges of the diagonal corners of the specimens, and a tenon groove was grooved towards the inner depth of the specimens at a speed of 50N / S until the grooving depth reached 2 / 3 of the total thickness of the insulating board. When visible cracks appeared or interlayer separation occurred in each layer of the insulating board, the test was stopped. At least 50 specimens were extracted from each example, and the test was repeated. The proportion of the number of cracked and delaminated specimens in the total sampling quantity was statistically counted, and the test results were recorded in Table 3.

[0062] The insulating boards prepared in Examples 1-10 were respectively cut into specimens of 300mm * 300mm. Holes were drilled vertically through the insulating board, and at least 3 through holes were drilled at equal intervals on the diagonal of the same specimen. When visible cracks appeared or interlayer separation occurred in each layer of the insulating board, the test was stopped. At least 50 specimens were extracted from each example, and the test was repeated. The proportion of the number of cracked and delaminated specimens in the total sampling quantity was statistically counted, and the test results were recorded in Table 3.

[0063] Table 3. Test Result Table

[0064]

[0065] It can be seen from the data in Table 3 that the insulating board prepared in this application has excellent anti-tenon-grooving / drilling cracking and anti-peeling effects. When the insulating board is further machined according to actual needs, it is not easy to cause problems such as cracks and interlayer peeling of the board, and it can be applied to more application scenarios.

[0066] The above are all the preferred embodiments of this application. The protection scope of this application is not limited by this. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. A method for manufacturing an insulating board, characterized in that, It includes the following steps: Preparation of the flat plate: After impregnating a fiber felt with a first thermosetting resin, it is hot-pressed and cured to obtain a flat plate (3); Preparation of the corrugated plate: After impregnating a fiber felt with a second thermosetting resin, it is hot-pressed and cured to obtain a corrugated plate (4); The cross-section of the corrugated plate (4) is in a corrugated shape, forming a number of parallel strip-shaped raised portions (41) and recessed portions (42); Lamination of the substrate: In a mold (7), a flat plate (3) obtained from the flat plate preparation step, a layer of polyurethane foam (6), and a corrugated plate (4) obtained from the corrugated plate preparation step are laid flat in sequence from bottom to top, and it is hot-pressed and cured under heating conditions to obtain a semi-finished substrate; A number of mounting grooves (43) arranged in a rectangular array are opened on the semi-finished substrate. The distance between adjacent two columns of mounting grooves (43) is equal to the distance between adjacent two raised portions (41), and the mounting grooves (43) are equally spaced on the same raised portion (41) to obtain a substrate (5); Molding of the insulating plate: In a mold (7), a layer of substrate (5), a layer of polyurethane foam (6), a layer of corrugated plate (4), a layer of polyurethane foam (6), and another layer of substrate (5) are laid in sequence from bottom to top. When laying, the side with the raised portion (41) of the lower substrate (5) faces upward, the side with the raised portion (41) of the upper substrate (5) faces downward, and the raised portion (41) on the middle corrugated plate (4) is snapped into the mounting grooves (43) on the upper and lower substrates (5), and it is hot-pressed and cured under heating conditions to obtain an insulating plate (8).

2. The method for manufacturing an insulating board according to claim 1, wherein: The first thermosetting resin and / or the second thermosetting resin is selected from any one of epoxy resin, phenolic resin, melamine formaldehyde resin, furan resin, polyurethane, and polyimide resin.

3. The method for manufacturing an insulating board according to claim 1, characterized in that: The thicknesses of the flat plate (3) and the corrugated plate (4) are the same or different.

4. The method for manufacturing an insulating board according to claim 3, characterized in that: The thickness of the flat plate (3) and / or the corrugated plate (4) is 0.5 - 1 mm.

5. The method for manufacturing an insulating board according to any one of claims 1-4, characterized in that: The depth of the mounting groove (43) is 1 / 3 - 2 / 3 of the height of the raised portion (41).

6. The method for manufacturing an insulating board according to claim 5, characterized in that: The height of the raised portion (41) is 2 - 4 mm, and the thickness of the insulating plate (8) is 5 - 10 mm.

7. The method for manufacturing an insulating board according to any one of claims 1-4, characterized in that: The fiber felt is a glass fiber felt or a PTFE needle-punched felt.

8. The method for manufacturing an insulating board according to any one of claims 1-4, characterized in that: The thickness of the fiber felt is 50 - 180 μm, and the grammage is 80 - 300 g / m 2 .

9. The method for manufacturing an insulating board according to any one of claims 1-4, characterized in that: Before the insulating plate molding step, the corrugated surface of the substrate (5) and / or the corrugated plate (4) is subjected to corona treatment.

10. An insulating plate is obtained by the insulating plate manufacturing method according to any one of claims 1 - 9.

Images