Salt-spray-resistant plate and preparation method thereof

Abstract

The invention discloses a salt spray resistant plate and a preparation method thereof. The plate is a composite plate which is prepared by coating a single plate with a salt-spray-resistant resin composition and then hot-pressing, curing and molding a plurality of layers of single plates. The salt-fog-resistant plate disclosed by the invention has good salt-fog-resistant performance in a humid environment under the condition of keeping high toughness and bonding strength. The combination of the N, N, N ', N'-tetraglycidyl-2, 6-bis (3-aminophenoxy) cyanobenzene epoxy resin and bisphenol A epoxy resin improves the toughness of the material, the combination of 4, 4 '-bis (2-trifluoromethyl-4-aminophenoxy) benzophenone and methylhexahydrophthalic anhydride improves the bonding strength of the material, and the combination of zinc phosphate and strontium chromate improves the bonding strength of the material. The salt spray resistance of the material is improved, and the synergistic interaction is realized.

Description

Technical Field

[0001] This invention belongs to the field of furniture board technology, specifically relating to a salt spray resistant board and its preparation method. Background Technology

[0002] Salt spray corrosion of wood-based panels in humid environments is a complex physicochemical process, primarily manifested as a decline in mechanical properties and structural damage. When wood is exposed to salt spray, salt solutions such as sodium chloride are drawn into the porous structure of the wood through capillary action. With periodic changes in ambient humidity, the dissolved salts repeatedly crystallize and dissolve, generating internal stress and causing the wood fibers to gradually peel off, macroscopically exhibiting a typical "fibrous" or "filamentous" appearance. The humid salt spray environment creates conditions for biological corrosion; wood is highly susceptible to mold and fungal growth, leading to blue stain and decay. This, combined with chemical corrosion, accelerates material failure. Furthermore, for engineered wood such as glued laminated timber, salt spray and moisture also erode the adhesive layer, resulting in a significant decrease in bonding performance, manifested as reduced adhesive shear strength and increased peeling rate.

[0003] To improve the salt spray corrosion resistance of wood-based panels, the industry has developed multi-layered protection strategies. For example, deep pyrolysis treatment of the wood substrate, or immersion in a specialized pretreatment solution formulated with modified phenolic resin, quaternary ammonium salt corrosion inhibitors, and nano-zinc oxide, can enhance the wood's corrosion resistance from within. Regarding surface protective coatings, high-performance coatings are the most direct barrier against the intrusion of corrosive media. Epoxy resin coatings have been proven to significantly improve the resistance of wood to seawater and various chemical media. More advanced composite coating technologies, such as polyaniline-fluorocarbon resin composite coatings, and protective materials with added nano-silica, can significantly enhance the coating's density, weather resistance, and salt spray resistance. At the engineering design and maintenance level, optimizing structural design is crucial. For example, minimizing metal connectors in wood structures, thickening or anti-corrosion treatment of necessary metal components, and ensuring good sealing and ventilation at joints to prevent the accumulation of corrosive condensates. Furthermore, in-situ protective treatments for existing structures, such as surface coating and fumigation, can effectively inhibit corrosion development and extend service life. Summary of the Invention

[0004] The purpose of this invention is to provide a salt spray resistant sheet material and its preparation method.

[0005] A salt spray resistant board, wherein the board is formed by coating a single veneer with a salt spray resistant resin composition and then hot-pressing and curing the multi-layer veneer to form a composite board.

[0006] The thickness of the single veneer is 0.5-6mm, and the number of single veneer layers in the multi-layer composite board is 2-30.

[0007] The resin composition comprises the following components in parts by weight: 70-150 parts of thermosetting resin, 5-15 parts of curing agent, and 10-30 parts of salt spray resistant agent.

[0008] The thermosetting resin is a mixture of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin and bisphenol A type epoxy resin in a mass ratio of 1:2.

[0009] The curing agent is a mixture of 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone and methylhexahydrophthalic anhydride in a mass ratio of 1:1.

[0010] The salt spray resistant agent is a mixture of zinc phosphate and strontium chromate in a mass ratio of 3:1.

[0011] The method for preparing the salt spray resistant board is as follows: coating the veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multilayer veneer to form a composite board; the hot-pressing temperature is 100-180℃, the hot-pressing pressure is 10-30MPa, and the time is 30-120min.

[0012] The veneer is wood veneer, fiber veneer, particleboard or bamboo veneer.

[0013] The coating amount of the salt spray resistant resin composition is 100-200 g / m². 2 .

[0014] The beneficial effects of this invention are as follows: The salt spray resistant sheet of this invention maintains high toughness and bonding strength while also exhibiting excellent salt spray resistance in humid environments. The combination of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin and bisphenol A type epoxy resin improves the material's toughness; the combination of 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone and methylhexahydrophthalic anhydride improves the material's bonding strength; and the combination of zinc phosphate and strontium chromate improves the material's salt spray resistance, with synergistic effects. Detailed Implementation

[0015] To facilitate understanding of the present invention, a more comprehensive description will be given below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0016] Example 1

[0017] A salt spray resistant board material is provided, wherein the board material is a composite board made by coating multiple layers of wood veneer with a salt spray resistant resin composition and then hot-pressing and curing the wood veneer. The wood veneer is 2 mm thick, and the multi-layer composite board has 12 layers of wood veneer.

[0018] The resin composition comprises the following components in parts by weight: 120 parts thermosetting resin, 10 parts curing agent, and 20 parts salt spray resistant agent. The thermosetting resin is a mixture of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin and bisphenol A type epoxy resin in a mass ratio of 1:2. The curing agent is a mixture of 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone and methylhexahydrophthalic anhydride in a mass ratio of 1:1. The salt spray resistant agent is a mixture of zinc phosphate and strontium chromate in a mass ratio of 3:1.

[0019] The preparation method of the salt spray resistant board is carried out according to the following steps: coating the wood veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multi-layer wood veneer to form a composite board; the hot-pressing temperature is 150℃, the hot-pressing pressure is 20MPa, and the time is 60min; the coating amount of the salt spray resistant resin composition is 160g / m². 2 .

[0020] Example 2

[0021] A salt spray resistant board material is provided, wherein the board material is a composite board made by coating multiple layers of wood veneer with a salt spray resistant resin composition and then hot-pressing and curing the wood veneer. The thickness of the wood veneer is 1 mm, and the number of wood veneer layers in the multi-layer composite board is 25.

[0022] The resin composition comprises the following components in parts by weight: 80 parts thermosetting resin, 6 parts curing agent, and 12 parts salt spray resistant agent. The thermosetting resin is a mixture of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin and bisphenol A type epoxy resin in a mass ratio of 1:2. The curing agent is a mixture of 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone and methylhexahydrophthalic anhydride in a mass ratio of 1:1. The salt spray resistant agent is a mixture of zinc phosphate and strontium chromate in a mass ratio of 3:1.

[0023] The preparation method of the salt spray resistant board is carried out according to the following steps: coating the wood veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multi-layer wood veneer to form a composite board; the hot-pressing temperature is 130℃, the hot-pressing pressure is 15MPa, and the time is 100min; the coating amount of the salt spray resistant resin composition is 120g / m². 2 .

[0024] Example 3

[0025] A salt spray resistant board material is provided, wherein the board material is formed by coating multiple layers of wood veneer with a salt spray resistant resin composition and then hot-pressing and curing the wood veneer to form a composite board. The thickness of the wood veneer is 3 mm, and the number of wood veneer layers in the multi-layer composite board is 8.

[0026] The resin composition comprises the following components in parts by weight: 130 parts thermosetting resin, 12 parts curing agent, and 25 parts salt spray resistant agent. The thermosetting resin is a mixture of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin and bisphenol A type epoxy resin in a mass ratio of 1:2. The curing agent is a mixture of 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone and methylhexahydrophthalic anhydride in a mass ratio of 1:1. The salt spray resistant agent is a mixture of zinc phosphate and strontium chromate in a mass ratio of 3:1.

[0027] The preparation method of the salt spray resistant board is carried out according to the following steps: coating the wood veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multi-layer wood veneer to form a composite board; the hot-pressing temperature is 180℃, the hot-pressing pressure is 25MPa, and the time is 35min; the coating amount of the salt spray resistant resin composition is 180g / m². 2 .

[0028] Comparative Example 1

[0029] A salt spray resistant board material is provided, wherein the board material is a composite board made by coating multiple layers of wood veneer with a salt spray resistant resin composition and then hot-pressing and curing the wood veneer. The wood veneer is 2 mm thick, and the multi-layer composite board has 12 layers of wood veneer.

[0030] The resin composition comprises the following components in parts by weight: 120 parts of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin, 10 parts of curing agent, and 20 parts of salt spray resistant agent. The curing agent is a mixture of 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone and methylhexahydrophthalic anhydride in a mass ratio of 1:1. The salt spray resistant agent is a mixture of zinc phosphate and strontium chromate in a mass ratio of 3:1.

[0031] The preparation method of the salt spray resistant board is carried out according to the following steps: coating the wood veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multi-layer wood veneer to form a composite board; the hot-pressing temperature is 150℃, the hot-pressing pressure is 20MPa, and the time is 60min; the coating amount of the salt spray resistant resin composition is 160g / m². 2 .

[0032] Comparative Example 2

[0033] A salt spray resistant board material is provided, wherein the board material is a composite board made by coating multiple layers of wood veneer with a salt spray resistant resin composition and then hot-pressing and curing the wood veneer. The wood veneer is 2 mm thick, and the multi-layer composite board has 12 layers of wood veneer.

[0034] The resin composition comprises the following components in parts by weight: 120 parts bisphenol A type epoxy resin, 10 parts curing agent, and 20 parts salt spray resistant agent. The curing agent is a mixture of 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone and methylhexahydrophthalic anhydride in a mass ratio of 1:1. The salt spray resistant agent is a mixture of zinc phosphate and strontium chromate in a mass ratio of 3:1.

[0035] The preparation method of the salt spray resistant board is carried out according to the following steps: coating the wood veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multi-layer wood veneer to form a composite board; the hot-pressing temperature is 150℃, the hot-pressing pressure is 20MPa, and the time is 60min; the coating amount of the salt spray resistant resin composition is 160g / m². 2 .

[0036] Comparative Example 3

[0037] A salt spray resistant board material is provided, wherein the board material is a composite board made by coating multiple layers of wood veneer with a salt spray resistant resin composition and then hot-pressing and curing the wood veneer. The wood veneer is 2 mm thick, and the multi-layer composite board has 12 layers of wood veneer.

[0038] The resin composition comprises the following components in parts by weight: 120 parts thermosetting resin, 10 parts 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone, and 20 parts salt spray resistant agent. The thermosetting resin is a mixture of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin and bisphenol A type epoxy resin in a mass ratio of 1:2. The salt spray resistant agent is a mixture of zinc phosphate and strontium chromate in a mass ratio of 3:1.

[0039] The preparation method of the salt spray resistant board is carried out according to the following steps: coating the wood veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multi-layer wood veneer to form a composite board; the hot-pressing temperature is 150℃, the hot-pressing pressure is 20MPa, and the time is 60min; the coating amount of the salt spray resistant resin composition is 160g / m². 2 .

[0040] Comparative Example 4

[0041] A salt spray resistant board material is provided, wherein the board material is a composite board made by coating multiple layers of wood veneer with a salt spray resistant resin composition and then hot-pressing and curing the wood veneer. The wood veneer is 2 mm thick, and the multi-layer composite board has 12 layers of wood veneer.

[0042] The resin composition comprises the following components in parts by weight: 120 parts thermosetting resin, 10 parts methylhexahydrophthalic anhydride, and 20 parts salt spray resistant agent. The thermosetting resin is a mixture of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin and bisphenol A type epoxy resin in a mass ratio of 1:2. The salt spray resistant agent is a mixture of zinc phosphate and strontium chromate in a mass ratio of 3:1.

[0043] The preparation method of the salt spray resistant board is carried out according to the following steps: coating the wood veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multi-layer wood veneer to form a composite board; the hot-pressing temperature is 150℃, the hot-pressing pressure is 20MPa, and the time is 60min; the coating amount of the salt spray resistant resin composition is 160g / m². 2 .

[0044] Comparative Example 5

[0045] A salt spray resistant board material is provided, wherein the board material is a composite board made by coating multiple layers of wood veneer with a salt spray resistant resin composition and then hot-pressing and curing the wood veneer. The wood veneer is 2 mm thick, and the multi-layer composite board has 12 layers of wood veneer.

[0046] The resin composition comprises the following components in parts by weight: 120 parts thermosetting resin, 10 parts curing agent, and 20 parts zinc phosphate. The thermosetting resin is a mixture of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin and bisphenol A type epoxy resin in a mass ratio of 1:2. The curing agent is a mixture of 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone and methylhexahydrophthalic anhydride in a mass ratio of 1:1.

[0047] The preparation method of the salt spray resistant board is carried out according to the following steps: coating the wood veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multi-layer wood veneer to form a composite board; the hot-pressing temperature is 150℃, the hot-pressing pressure is 20MPa, and the time is 60min; the coating amount of the salt spray resistant resin composition is 160g / m². 2 .

[0048] Comparative Example 6

[0049] A salt spray resistant board material is provided, wherein the board material is a composite board made by coating multiple layers of wood veneer with a salt spray resistant resin composition and then hot-pressing and curing the wood veneer. The wood veneer is 2 mm thick, and the multi-layer composite board has 12 layers of wood veneer.

[0050] The resin composition comprises the following components in parts by weight: 120 parts thermosetting resin, 10 parts curing agent, and 20 parts strontium chromate. The thermosetting resin is a mixture of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin and bisphenol A type epoxy resin in a mass ratio of 1:2. The curing agent is a mixture of 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone and methylhexahydrophthalic anhydride in a mass ratio of 1:1.

[0051] The preparation method of the salt spray resistant board is carried out according to the following steps: coating the wood veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multi-layer wood veneer to form a composite board; the hot-pressing temperature is 150℃, the hot-pressing pressure is 20MPa, and the time is 60min; the coating amount of the salt spray resistant resin composition is 160g / m². 2 .

[0052] Experimental example:

[0053] The static bending strength (MPa) of the boards prepared in Examples 1-3 and Comparative Examples 1-2 was determined according to GB / T 17657-2022 "Test Methods for Physical and Chemical Properties of Wood-based Panels and Decorative Wood-based Panels". The experimental results were statistically analyzed using SPSS 24.0 software, and the quantitative data were analyzed using... (mean ± standard deviation) represents the mean. The Kolmogorov-Smirnov test was used to test the normality of the data. For normally distributed data, the t-test was used to compare the differences in means between two groups. A p-value < 0.05 was considered statistically significant. The results are shown in Table 1.

[0054] Table 1

[0055]

[0056] Note: * indicates that compared with Example 1 group, P<0.05.

[0057] The internal bond strength (MPa) of the composite boards prepared in Examples 1-3 and Comparative Examples 3-4 was measured, and the results are shown in Table 2.

[0058] Table 2

[0059]

[0060] Note: * indicates that compared with Example 1 group, P<0.05.

[0061] The salt spray resistance of the resin compositions prepared in Examples 1-3 and Comparative Examples 5-6 was determined according to GB / T 1771. The results are shown in Table 3.

[0062] Table 3

[0063]

[0064] Note: * indicates that compared with Example 1 group, P<0.05.

[0065] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A salt spray resistant board, characterized in that, The board is made by coating a single veneer with a salt spray resistant resin composition and then hot-pressing and curing the multi-layer veneers to form a composite board.

2. The salt spray resistant plate according to claim 1, characterized in that, The thickness of the single veneer is 0.5-6mm, and the number of single veneer layers in the multi-layer composite board is 2-30.

3. The salt spray resistant plate according to claim 1, characterized in that, The resin composition comprises the following components in parts by weight: 70-150 parts of thermosetting resin, 5-15 parts of curing agent, and 10-30 parts of salt spray resistant agent.

4. The salt spray resistant plate according to claim 3, characterized in that, The thermosetting resin is a mixture of N,N,N',N'-tetraglycidyl-2,6-bis(3-aminophenoxy)benzonitrile epoxy resin and bisphenol A type epoxy resin in a mass ratio of 1:

2.

5. The salt spray resistant plate according to claim 3, characterized in that, The curing agent is a mixture of 4,4'-bis(2-trifluoromethyl-4-aminophenoxy)benzophenone and methylhexahydrophthalic anhydride in a mass ratio of 1:

1.

6. The salt spray resistant plate according to claim 3, characterized in that, The salt spray resistant agent is a mixture of zinc phosphate and strontium chromate in a mass ratio of 3:

1.

7. The method for preparing the salt spray resistant plate according to claim 1, characterized in that, The following steps are performed: coating the veneer with a salt spray resistant resin composition, and then hot-pressing and curing the multilayer veneer to form a composite board; the hot-pressing temperature is 100-180℃, the hot-pressing pressure is 10-30MPa, and the time is 30-120min.

8. The method for preparing the salt spray resistant plate according to claim 7, characterized in that, The veneer is wood veneer, fiber veneer, particleboard or bamboo veneer.

9. The method for preparing the salt spray resistant plate according to claim 7, characterized in that, The coating amount of the salt spray resistant resin composition is 100-200 g / m². 2 .

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