Wood reconstituted material with mildew-proof function and preparation method thereof

Abstract

The present application provides a kind of wood recombination material with mildew-proof function and its preparation method.The surface and / or interior of the wood recombination material has a mildew-proof agent;And, the surface and / or interior of the wood recombination material has point-creating microcrack structure;So that the surface and / or interior of the wood recombination material has multiple scale penetration channels;The cell intercellular layer between the wood recombination material and the cell wall has a plurality of cracks, and the crack on the cell wall is less than the crack between the cell intercellular layer.The wood recombination material of the present application not only solves the problem of mildew in outdoor use in nature, and mechanical properties, dimensional stability etc.are also excellent.

Description

TECHNICAL FIELD

[0001] The present application relates to a wood recombination material with a mildew-proof function and a preparation method thereof, and belongs to the technical development and modification field of new wood or bamboo materials. BACKGROUND

[0002] Among various wood and bamboo-based composite materials, the wood recombination material has excellent mechanical strength and mechanical processing performance as a high-value-added material, can replace part of steel and cement, and is applied to indoor and outdoor buildings, furniture materials, landscape gardens and other fields, and has a very good development prospect.

[0003] In outdoor harsh environments, untreated wood recombination materials can easily have some problems during use, mainly manifested as surface cracking, mildew, rotting and the like, especially mildew, which seriously affects the strength and quality of the wood recombination material, and thus mildew-proofing becomes a difficult problem to be solved for the wood recombination material. The density of the wood recombination material is usually 0.9 g / cm 3 -1.2 g / cm 3 The large density makes the wood recombination material have good compactness and low permeability, so it is difficult for the mildew-proofing agent to impregnate the wood recombination material under normal temperature and pressure conditions, and the small drug loading cannot play the effect of the mildew-proofing agent, thereby seriously hindering the preparation of the mildew-proof wood recombination material.

[0004] In order to enhance the impregnation effect of the agent, the existing technology usually adopts methods such as steaming, boiling, microwave pretreatment and alkali pretreatment to improve the liquid permeability of wood and bamboo. The steaming method and the boiling method have a long operation time and affect the dimensional stability of wood and bamboo, and the microwave pretreatment method and the alkali pretreatment method have high cost and affect the mechanical strength of wood and bamboo.

[0005] Reference Document 1 discloses a preparation method of an outdoor wood recombination material. The method comprises the following steps: (1) taking wood veneer strips as raw materials, drying, impregnating glue, and low-temperature drying to prepare unit materials of the wood recombination material; (2) directionally recombining and cold-pressing the unit materials in a mold to form a square material; (3) continuously heat-curing and cooling the cold-pressed square material in the mold to prepare a wood recombination square material; (4) cutting the wood recombination square material into wood recombination boards of a certain thickness according to the use requirements, and then impregnating and treating the wood recombination boards in a low-temperature oil heating pool for a certain time; (5) taking out the wood recombination boards impregnated with the heat-keeping oil from the oil heating pool and directly putting them into a flat plate breaking machine for high-temperature hot pressing, and finally processing the wood recombination boards into the outdoor wood recombination material through sanding and painting processes. However, this method also has a long operation time, large energy consumption and affects the dimensional stability of wood.

[0006] Reference Document 2 discloses a wood recombination material with a mildew-proof function and a preparation method thereof. The wood recombination material with a mildew-proof function is obtained by adding a multi-component complex mildew-proof agent composed of azoles, isothiazolinones and pyrethroids and a low molecular weight phenolic resin into wood bundles. The preservative has a synergistic effect of azoles, isothiazolinones and pyrethroids. However, in fact, due to the large density of the wood recombination material, the wood recombination material has good compactness and low permeability, resulting in low drug loading. Even if the multi-component complex mildew-proof agent composed of azoles, isothiazolinones and pyrethroids has a synergistic effect, the multi-component complex mildew-proof agent cannot penetrate into the wood recombination material, and wood recombination material with excellent mildew-proof effect cannot be obtained.

[0007] Reference Document:

[0008] Reference Document 1: CN106863512A

[0009] Reference Document 2: CN107584611A SUMMARY

[0010] Problems to be Solved by the Invention

[0011] In view of the technical problems existing in the prior art, for example: long operation time, affecting the dimensional stability of wood and bamboo, high cost, affecting the mechanical strength of wood and other problems, the present application first provides a wood recombination material with a mildew-proof function. The wood recombination material of the present application not only solves the problem of easy mildew in outdoor use in essence, but also has excellent mechanical properties.

[0012] Further, the wood recombination material of the present application has excellent dimensional stability.

[0013] Further, the preparation method of the present application is simple and easy to operate, simple and fast to operate, low in cost, and the wood recombination material prepared has excellent mildew-proof effect, and has wide application prospect in outdoor and landscape aspects.

[0014] Solution for Solving the Problem

[0015] The present application provides a wood recombination material, the surface and / or interior of the wood recombination material has a mildew-proof agent; and,

[0016] The surface and / or interior of the wood recombination material has a point-creating micro-crack structure; so that the surface and / or interior of the wood recombination material has a multi-scale permeation channel;

[0017] The wood recombination material has a plurality of cracks between the cell interlayer and on the cell wall, and the cracks on the cell wall are less than the cracks between the cell interlayer.

[0018] According to the wood recombination material, the drug loading of the antifungal agent in the wood recombination material is 0.02-0.1 kg / m 3 ; and / or

[0019] The water content of the wood recombination material is 6-12%.

[0020] According to the wood recombination material, the hole in the point-creating micro-crack structure has a diameter of 0.5-3 mm; and / or,

[0021] The hole in the point-creating micro-crack structure extends from the surface of the wood recombination material to the interior by a distance of 0.5-3 mm; and / or,

[0022] The radial section area of the point-creating micro-crack structure is 0.5-5% based on the radial section area of the wood recombination material.

[0023] According to the wood recombination material, the antifungal agent comprises one or more than two combinations of iodopropynyl butylcarbamate, quaternary ammonium copper, copper azole, isothiazolone, and titanium dioxide.

[0024] According to the wood recombination material, the outer surface of the wood recombination material further comprises a decorative layer; preferably, the decorative layer is derived from a thermosetting resin; more preferably, the thermosetting resin comprises isocyanate.

[0025] The application further provides a preparation method of the wood recombination material, comprising the following steps:

[0026] Obtaining a substrate derived from wood material and / or bamboo material;

[0027] Forming a point-creating micro-crack structure on the surface and / or interior of the substrate, so that the surface and / or interior of the substrate have multi-scale permeation channels; and the cell interlayer between the substrate and the cell wall have a plurality of cracks, the cracks on the cell wall are less than the cracks between the cell interlayer, to obtain a point-creating micro-crack substrate;

[0028] Immersing the point-creating micro-crack substrate in an antifungal agent solution to obtain a wood recombination material.

[0029] According to the preparation method, the water content of the substrate is 5-15%; and / or,

[0030] Using a point-creating micro-crack device to apply vertical pressure to the substrate to generate a point-creating micro-crack structure on the surface and / or interior of the substrate to form a point-creating micro-crack structure network; preferably, the vertical pressure is 1.8-2.2 MPa.

[0031] According to the preparation method, the mass concentration of the antifungal agent in the antifungal agent solution is 0.05-0.5%; and / or

[0032] The impregnation time is 5-60 min.

[0033] According to the preparation method, the wood recombination material is further coated with a thermosetting resin; preferably, the thermosetting resin comprises isocyanate.

[0034] According to the preparation method, the loading amount of the thermosetting resin is 0.3-0.6% based on the total mass of the wood recombination material.

[0035] Effects of the application

[0036] The wood recombination material of the application not only solves the problem of mold in outdoor use in essence, but also has excellent mechanical properties and dimensional stability.

[0037] The preparation method of the wood recombination material of the application can greatly improve the permeability of the wood recombination material without affecting the mechanical properties and dimensional stability, and has the advantages of simple operation, rapid effect and obvious effect, and solves the problem of poor permeability of the wood recombination material. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 The preparation process of one embodiment of the wood recombination material of the application is shown;

[0039] Figure 2 The electron microscope image of the point-creating micro-crack structure of the radial section of the wood recombination material of the application is shown;

[0040] Figure 3 The macroscopic schematic diagram of the radial section of one embodiment of the wood recombination material of the application is shown.

[0041] Figure 4 The electron microscope image of the point-creating micro-crack structure of the cross section of the wood recombination material of the application is shown;

[0042] Figure 5 The electron microscope image of the multi-scale permeation channel in the interior of the wood recombination material of the application is shown;

[0043] Figure 6 The antifungal effect comparison diagram of examples 1-3 and comparative examples 1-3 is shown. DETAILED DESCRIPTION

[0044] Various illustrative embodiments, features and aspects of the present application are discussed in detail below. The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations.

[0045] In addition, for purposes of explanation, numerous specific details are set forth in the description below. Formulations of the application maybe practiced without the specific details (e.g., concentrations, methods, etc.) set forth in this description as part of the enabling teaching of the application. In other instances, well known methods, structures, apparatuses, and steps have not been described in detail in order to avoid obscuring the application.

[0046] Unless specifically stated otherwise, as used herein, all measurements are understood to be made at standard temperature and pressure and all units specified are standard international units (SI) unless specified otherwise. Values, ranges, and values for values stated in this application are understood to be used in their broadest form, encompassing systemically unavoidable errors in industrial production.

[0047] In this specification, the meaning expressed by "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process.

[0048] In this specification, references to "some embodiments," "other embodiments," "exemplary embodiments," etc., indicate that the description is subject to various interpretations and that the embodiments do not limit the scope of the application. That is, the above-mentioned terms mean that at least one of the respective features is included in at least one embodiment of the application.

[0049] In this specification, a numerical range expressed by "numerical value A to numerical value B" means a range including the end values A and B.

[0050] In this specification, when "room temperature" is used, the temperature can be 15 to 25°C.

[0051] <First aspect>

[0052] A first aspect of the present application provides a wood reconstituted material, wherein the wood reconstituted material has an antifungal agent on a surface and / or inside thereof; and

[0053] The wood reconstituted material has a point-creation microcrack structure on a surface and / or inside thereof, so that the inside of the wood reconstituted material has a multi-scale permeation channel.

[0054] The wood reconstituted material has a plurality of cracks between cell middle lamellas and on cell walls, and the cracks on the cell walls are less than the cracks between the cell middle lamellas.

[0055] The wood-based reconstituted material of this invention not only fundamentally solves the problem of mold growth when used outdoors, but also has excellent mechanical properties.

[0056] In this invention, such as Figures 2-4 As shown, the point-crack microcrack structure is formed by applying point-like external force to the surface of the substrate, creating a circular hole-like wound on the surface and / or inside. The crack starts from the wound and gradually extends into the material along the stress direction, forming microcracks of different sizes.

[0057] Specifically, cracks formed by applying point-like external forces are called point-crack microcrack structures, i.e., multi-scale microcrack structures. These structures are multi-scale; on a macroscopic scale, they have pores. Point-crack microcrack structures can be uniformly distributed and appear as circular pores (points) on the surface of wood-based reconstituted materials, and conical in the thickness direction within the material, with the radius of curvature at the crack tip approaching zero. On a microscopic scale, point-crack microcrack structures can exist between the intercellular layers and on the cell walls. The crack gaps between cells can be 2–10 μm, and the crack size on the cell walls can be 0.5–5 μm.

[0058] In some specific implementations, the diameter of the pores in the dot-crack micro-fracture structure is 0.5-3 mm, for example: 0.8 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, etc. In this invention, if the diameter of the pores in the dot-crack micro-fracture structure is too small, the enhanced penetration effect will be insignificant; if the diameter is too large, it will affect the aesthetics of the surface and reduce the mechanical properties to some extent. Furthermore, the distance (i.e., the pore depth) of the pores in the dot-crack micro-fracture structure extending inward (in the thickness direction) from the surface of the wood-based reconstituted material is 0.5-3 mm, for example: 0.8 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, etc.

[0059] The inventors of this invention discovered that, under external loads, the cell wall is the most significant component affecting the mechanical properties of wood. Pitted microcracks mainly exist in the middle lamella of cells, with only a very small number of cell walls developing cracks, thus having virtually no impact on mechanical properties. Furthermore, as... Figure 5 As shown, the surface and / or interior of the wood-based reconstituted material of the present invention have multi-scale permeation channels, and the intercellular layers and cell walls of the wood-based reconstituted material have multiple cracks, which allows the antifungal agent to penetrate more into the wood-based reconstituted material, resulting in a high loading capacity of the antifungal agent in the wood-based reconstituted material, fundamentally solving the problem of mold growth when used outdoors.

[0060] Specifically, in this invention, the loading of the antifungal agent in the wood-based reconstituted material is 0.02-0.1 kg / m³. 3 For example: 0.03 kg / m 3 0.05kg / m3 0.07 kg / m 3 0.09 kg / m 3 When the drug loading of the antifungal agent is 0.02-0.1 kg / m 3 The wood reconstituted material has been sufficient to prevent mold when the drug loading of the antifungal agent is 0.02-0.1 kg / m

[0061] For the antifungal agent, the present application is not particularly limited and can be any feasible antifungal agent in the art. Specifically, the antifungal agent comprises one or a combination of two or more of iodopropynyl butylcarbamate, quaternary ammonium copper, copper azole, isothiazolone, titanium dioxide, etc., and iodopropynyl butylcarbamate is preferably used.

[0062] Further, in the present application, the moisture content of the wood reconstituted material is 6-12%. When the moisture content of the wood reconstituted material is 6-12%, it is beneficial for outdoor use.

[0063] In the point-creating micro-crack structure of the present application, the radial cross-sectional area of the point-creating micro-crack structure is too small, the penetration effect is poor, and the radial cross-sectional area of the point-creating micro-crack structure is too large, the mechanical properties decrease significantly, therefore, in the present application, the area of the hole of the point-creating micro-crack structure is 0.5-5%, for example: 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, etc., based on the radial cross-sectional area of the wood reconstituted material being 100%.

[0064] In some specific embodiments, the outer surface of the wood reconstituted material further comprises a veneer layer; preferably, the veneer layer is derived from a thermosetting resin; more preferably, the thermosetting resin comprises isocyanate.

[0065] The inventors of the present application found that the veneer layer also plays a certain sealing role, making the anti-leaching property of the wood reconstituted material of the present application very excellent. In particular, the adhesive effect of the veneer layer can enhance the anti-leaching property of the wood reconstituted material to some extent. Specifically, the thermosetting resin can penetrate into the point-creating micro-crack structure, thereby filling the cell interlayer, micro-crack cell wall and cell cavity of the wood reconstituted material, locking the antifungal agent firmly inside the wood reconstituted material, preventing its volatilization in the air and leaching under adverse weather conditions.

[0066] Further, the surface layer of the present application can also improve the dimensional stability. Specifically, the thermosetting resin of the present application can penetrate into the intercellular layer, cell cavity and cell wall of the substrate through the point-creating micro-crack structure, and after drying and curing, the porosity is reduced, and the connection between the internal structures of the substrate is more closely, thus the shrinkage and swelling are less likely to occur. At the same time, the thermosetting resin will react with the hydroxyl groups in the chemical components of the substrate, reducing the number of hydroxyl groups and the hydrophilicity, thereby inhibiting the deformation of the lignin reconstituted material. In addition, after using the thermosetting resin as the surface layer, the surface contact angle of the lignin reconstituted material can be increased from 30° to 120°, which has a certain hydrophobicity, and moisture is less likely to enter the interior of the lignin reconstituted material. Therefore, the surface layer of the present application can improve the dimensional stability of the lignin reconstituted material as a whole through the synergistic effect of multiple aspects.

[0067] <Second aspect>

[0068] As shown in Figure 1 the second aspect of the present application provides a preparation method of the lignin reconstituted material according to the first aspect of the present application, which comprises the following steps:

[0069] obtaining a substrate, wherein the substrate is derived from lignin material and / or bamboo material;

[0070] forming a point-creating micro-crack structure on the surface and / or inside of the substrate, and making the inside of the substrate have a multi-scale permeation channel; and the cell intercellular layer and the cell wall of the substrate have a plurality of cracks, and the cracks on the cell wall are less than the cracks between the cell intercellular layers, to obtain a point-creating micro-crack substrate;

[0071] immersing the porous substrate in a mildew-proof agent solution to obtain a lignin reconstituted material with a mildew-proof effect.

[0072] The preparation method of the lignin reconstituted material of the present application can greatly improve the permeability of the lignin reconstituted material without affecting the mechanical properties, and the operation is simple, rapid and obvious in effect, and solves the problem of poor permeability of the lignin reconstituted material.

[0073] Specifically, the substrate of the present application at least includes lignin material and / or bamboo material. In the present application, the lignin material in the lignin reconstituted material can be a multi-layer structure, and the bamboo material in the lignin reconstituted material can also be a multi-layer structure. For example, when using wood fiberized veneer as lignin material, a plurality of wood fiberized veneers can be bonded together as lignin material; when using bamboo fiberized veneer as bamboo material, a plurality of bamboo fiberized veneers can be bonded together as bamboo material.

[0074] For the source of the wood material, it is obtained by mechanical defibration using various wood as raw material. Specifically, in the present application, considering the penetration performance of the antifungal agent, it is preferred to use the wood material as the base material.

[0075] For the wood material, firstly, rotary cut veneer is formed by rotary cutting, and the thickness of the veneer can be 3-20 mm, and then it is defibrated by non-continuous line cracking directional mechanical fine defibration to form the directional line cracking wood fiberized veneer with uniform unit form and uniform surface density distribution, so as to prepare the base material. For the mechanical defibration method, it can be the commonly used mechanical defibration method in the art.

[0076] For the source of the bamboo material, it can be obtained by mechanical defibration, which can effectively remove wax and yellow film, defibrate bamboo fibers, and process the bamboo into a network of bamboo flake curtain. The bamboo flake curtain is continuously cracked in the longitudinal direction, loosely and staggered in the transverse direction, and the arrangement direction of the bamboo fibers is maintained, so as to prepare the base material. For the mechanical defibration method, it can be the commonly used mechanical defibration method in the art. Specifically, the bamboo can be defibrated by bamboo wax and yellow defibration equipment. For example, it can be the wax and yellow defibration machine disclosed in patent document CN101733794A or the defibration machine disclosed in CN101486214A. In some specific embodiments, the bamboo material is bamboo bundle or bamboo fiberized veneer.

[0077] Further, the fiberized veneer is impregnated with adhesive, and the adhesive is adsorbed and penetrated into the surface layer of the fiberized veneer by using the water content gradient of the fiberized veneer and the adhesive. Then, the impregnated fiberized veneer is drained for 1-5 min and then dried to obtain the impregnated product. For the drying method, a mesh belt dryer or a tunnel dryer is usually used, or natural air drying is used.

[0078] For the drying temperature, the present application does not make special limitation, and considering not to damage the impregnated product, the drying temperature is preferably not more than 70°C, and the final water content of the impregnated product can be 5%-15%, preferably 10%-12%, for example, 7%, 9%, 11%, 13%, etc.

[0079] For the amount of adhesive, the present application does not make special limitation, and it can be set as needed. Specifically, the amount of adhesive can be controlled by the impregnation time. For the amount of adhesive, generally, the total mass of the fiberized veneer is 100%, and the amount of adhesive (solid content) is 10-15%. For the adhesive, phenolic resin adhesive can be used, and water-soluble phenolic resin adhesive is preferred. Specifically, adhesive solution can be used for impregnation. In the adhesive solution, the mass concentration of the adhesive is 10-30%, for example, 12%, 15%, 18%, 20%, 22%, 25%, 28%, etc.

[0080] Finally, the impregnated product is subjected to hot pressing to obtain the substrate. The hot pressing process can adopt the "hot-in and cold-out" process, which is to load the board blank when the hot pressing plate of the hot press is in a "hot" state, at this time the temperature of the hot pressing plate is 135-145℃, and after loading, the pressure is immediately raised to the specified pressure and maintained for a specified time. The pressure of the hot pressing is generally 3.0-3.5MPa, and the time of the hot pressing is 10-60min. After hot pressing, water cooling is carried out under a pressure of 3.0-3.5MPa, so that the board blank is unloaded from the hot press in a "cold" state.

[0081] Further, in the present application, if the water content of the substrate is relatively high and the water content gradient is small, it is not conducive to the impregnation of the mildew-proof agent, affecting the mildew-proof effect; and if the water content is too low, the drying efficiency will be reduced, and the energy consumption and manufacturing cost will be increased. Therefore, in the present application, the water content of the substrate obtained above can be adjusted to 6-12%, for example: 7%, 8%, 9%, 10%, 11%, etc.

[0082] In some specific embodiments, a point-creating micro-cracking device can be used to apply vertical pressure to the substrate to form a series of point-creating micro-cracking structures on the surface of the substrate, forming a network of point-creating micro-cracking structures; so that the interior of the substrate has multiple-scale permeation channels; the cell interlayer between the substrate and the cell wall has a plurality of cracks, and the cracks on the cell wall are less than the cracks between the cell interlayer.

[0083] The present application improves the permeability of the wood recombination material by a simple and efficient point-creating micro-cracking method, thereby enhancing the impregnation effect of the mildew-proof agent, preparing a mildew-proof wood recombination material with excellent performance, and solving the problem of mold in outdoor use of the wood recombination material.

[0084] The present application does not particularly limit the vertical pressure applied to the substrate by the point-creating micro-cracking device, which can be set as needed, as long as the desired point-creating micro-cracking structure is obtained. Specifically, the vertical pressure can be 1.8-2.2MPa, for example: 1.9MPa, 2MPa, 2.1MPa, etc.

[0085] In some specific embodiments, the mass concentration of the mildew-proof agent in the mildew-proof agent solution is 0.05-0.5%, for example: 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, etc. When the mass concentration of the mildew-proof agent is 0.05-0.5%, enough mildew-proof agent can be impregnated in the substrate. As for the solvent for dissolving the mildew-proof agent, the present application does not particularly limit it, and any commonly used solvent in the art can be used, such as water, ethanol, etc.

[0086] Further, the impregnation time is 5-60 min, for example: 10 min, 20 min, 30 min, 40 min, 50 min, etc. After impregnation, drying can be performed to obtain the desired wood reorganized material. Generally, the moisture content of the wood reorganized material is 6-12%, for example 7%, 8%, 9%, 10%, 11%, etc.

[0087] In some specific embodiments, the preparation method further comprises the step of using a thermosetting resin to finish the wood reorganized material; preferably, the thermosetting resin comprises isocyanate.

[0088] Specifically, the finishing is performed on the surface of the wood reorganized material in a coating manner, and then the thermosetting resin can be cured by heating and drying to obtain the finished wood reorganized material. The temperature of heating is not particularly limited in the present application, and is generally determined according to the selected thermosetting resin. Specifically, the temperature of heating can be 40-80℃, for example: 45℃, 50℃, 55℃, 60℃, 65℃, 70℃, 75℃, etc.

[0089] Further, the thermosetting resin is uniformly loaded on the surface of the wood reorganized material, and specifically, the loading amount of the thermosetting resin is 0.3-0.6% based on 100% of the total mass of the wood reorganized material, for example: 0.35%, 0.4%, 0.45%, 0.5%, 0.55%, etc. When the loading amount of the thermosetting resin is 0.3-0.6%, the desired finishing layer can be obtained.

[0090] The preparation method of the present application is simple and easy to operate, fast and low in cost, and the wood reorganized material prepared has excellent mildew-proof effect, and has wide application prospect in outdoor and landscape applications.

[0091] Examples

[0092] The embodiments of the present application will be described in detail below with reference to examples, but those skilled in the art will understand that the following examples are only used to illustrate the present application, and should not be regarded as limiting the scope of the present application. The specific conditions are not specified in the examples, and are carried out according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used are not specified by the manufacturer, and are all conventional products that can be obtained by purchase.

[0093] In the examples, the Schima superba substrate is prepared as follows.

[0094] First, a rotary cut veneer is formed by rotary cutting, and the thickness of the veneer is 5 mm. Then, a fibrous veneer with uniform unit morphology and uniform surface density distribution is formed by non-continuous line cracking directional mechanical fine disintegration technology, and the size of the fibrous veneer is 450 mm x 160 mm x 5 mm.

[0095] The fibrids are dried to a moisture content of about 11%. The fibrids are then dipped into a glue tank to impregnate with a water-soluble phenol-formaldehyde resin adhesive having a mass concentration of 15% for 15 minutes. The amount of adhesive (solid content) is 13% based on the total mass of the fibrids, which is taken as 100%. The impregnated fibrids are then drained for 5 minutes and dried at 60°C for 3 hours to obtain a glue-impregnated product, which has a final moisture content of about 11%.

[0096] The glue-impregnated product is subjected to hot pressing to form a board blank. The board blank is loaded into the hot press when the hot press plates are in a "hot" state, and the temperature of the hot press plates is about 140°C. The pressure is immediately increased to about 3.2 MPa and maintained for 30 minutes. The board blank is then unloaded from the hot press in a "cold" state by cooling under pressure. A szechwan chestnut substrate having a size of 450 mm x 160 mm x 20 mm and a density of 1.00 g / cm 3 is finally prepared.

[0097] The szechwan chestnut substrates in the examples and comparative examples are prepared by the above method.

[0098] Example 1

[0099] (1) : A szechwan chestnut substrate sample having a size of 50 mm x 20 mm x 20 mm is selected. The wood reconstituted material is naturally air-dried to a moisture content of 10% at 20°C. The density of the dried szechwan chestnut substrate is 1.0 g / cm 3 .

[0100] (2) : The szechwan chestnut substrate in step (1) is subjected to a vertical pressure of 2.0 MPa using a point-creating micro-crack device with a 1.0 mm conical protrusion on the surface, so that the surface of the szechwan chestnut substrate has a point-creating micro-crack structure. The diameter of the holes in the point-creating micro-crack structure is 1.0 mm, and the holes in the point-creating micro-crack structure extend inward from the surface of the wood reconstituted material by a distance (i.e. the depth of the holes) of 1.0 mm.

[0101] (3) : The step in (2) is repeated once to continue creating more point-creating micro-crack structures on the surface of the szechwan chestnut substrate using the point-creating micro-crack device. The radial cross-sectional area of the point-creating micro-crack structure is 3.0% based on the total radial cross-sectional area of the szechwan chestnut substrate, which is taken as 100%. A point-creating micro-crack substrate is thus prepared and reserved for use.

[0102] (4) : 2.5 g of a 6% mass fraction of iodine propargyl alcohol butyl carbamate solution is mixed with 97.5 g of distilled water to prepare a 0.15% mass concentration of a mildew-proof agent solution.

[0103] (5) : At normal temperature and pressure, immerse the point-creating micro-crack substrate prepared in step (3) in the mildew-proof agent solution of step (4), so that the point-creating micro-crack substrate is completely immersed below the liquid level of the mildew-proof agent solution and kept for 30 minutes until the point-creating micro-crack substrate is saturated.

[0104] (6) : Take out the point-creating micro-crack substrate immersed with the mildew-proof agent of step (5), wipe it gently with filter paper until no liquid drops fall, weigh and calculate the drug loading amount as 0.06 kg / m 3 , and then naturally air dry to 8% moisture content to obtain the drug-loaded product for standby.

[0105] (7) : Brush a thin layer of isocyanate resin on the surface of the drug-loaded product obtained in step (6), with an isocyanate loading amount of 0.4%, to ensure that the isocyanate is fully penetrated into each point-creating micro-crack structure on the surface, dry at 60°C for 6h until the isocyanate is cured, to obtain the wood reconstituted material.

[0106] Example 2

[0107] (1) : Select a Gmelina hainnensis substrate sample with a size of 50mm x 20mm x 20mm, and naturally air dry the wood reconstituted material at 20°C to 10% moisture content. The density of the dried Gmelina hainnensis substrate is 1.0 g / cm 3 for standby.

[0108] (2) : Use a point-creating micro-crack device with a 1.0mm conical protrusion on the surface to apply a vertical pressure of 2.0MPa to the Gmelina hainnensis substrate of step (1), so that the surface of the Gmelina hainnensis substrate has a point-creating micro-crack structure, wherein the hole diameter in the point-creating micro-crack structure is 1.0mm, and the distance (i.e. the depth of the hole) that the hole in the point-creating micro-crack structure extends from the surface of the wood reconstituted material is 1.0mm.

[0109] (3) : Repeat step (2) for 2-3 times to continue using the point-creating micro-crack device to obtain more point-creating micro-crack structures on the surface of the Gmelina hainnensis substrate. The radial cross-sectional area of the point-creating micro-crack structure is 4.5% based on the radial cross-sectional area of the Gmelina hainnensis substrate as 100%, to prepare a point-creating micro-crack substrate for standby.

[0110] (4) : Mix 2.5g of 6% mass fraction of iodine propargyl alcohol butyl carbamate solution with 97.5g of distilled water and stir uniformly to prepare a mildew-proof agent solution with a mass concentration of 0.15%.

[0111] (5) : At normal temperature and pressure, immerse the point-creating micro-crack substrate prepared in step (3) in the mildew-proof agent solution of step (4), so that the point-creating micro-crack substrate is completely immersed below the liquid level of the mildew-proof agent solution and kept for 30 minutes until the point-creating micro-crack substrate is saturated.

[0112] (6) : The point-creviced substrate impregnated with the mildewcide in step (5) was taken out and gently wiped with filter paper until no liquid drops fell down, weighed and calculated its drug loading as 0.08 kg / m 3 , and then naturally air-dried to 8% moisture content to obtain the drug-loaded product, ready for use.

[0113] (7) : The surface of the drug-loaded product obtained in step (6) was brushed with a thin layer of isocyanate resin, and the isocyanate loading was 0.4%, to ensure that the isocyanate was fully penetrated into each point-creviced structure on the surface, and dried at 60°C for 6h until the isocyanate was cured, to obtain the wood reconstituted material.

[0114] Example 3

[0115] (1) : A sample of the phellodendron substrate with a size of 50mm x 20mm x 20mm was selected, and the wood reconstituted material was naturally air-dried to 10% moisture content at 20°C, and the density of the dried phellodendron substrate was 1.0 g / cm 3 , ready for use.

[0116] (2) : The phellodendron substrate in step (1) was subjected to a vertical pressure of 2.0 MPa by using a point-crevicing device with a 1.0mm conical protrusion on the surface, so that the phellodendron substrate surface had a point-creviced structure, wherein the hole diameter in the point-creviced structure was 1.0mm, and the distance (i.e. the depth of the hole) that the hole in the point-creviced structure extended from the surface of the wood reconstituted material to the inside was 1.0mm.

[0117] (3) : The step (2) was repeated once, and the surface of the phellodendron substrate was subjected to more point-creviced structures by using the point-crevicing device. The radial cross-sectional area of the point-creviced structure was 3.0% based on the radial cross-sectional area of the phellodendron substrate, to obtain the point-creviced substrate, ready for use.

[0118] (4) : 1.67g of iodopropynyl butylcarbamate solution with a mass fraction of 6% was mixed with 98.33g of distilled water and stirred uniformly to obtain a mildewcide solution with a mass concentration of about 0.1%.

[0119] (5) : The point-creviced substrate prepared in step (3) was immersed in the mildewcide solution in step (4) at normal temperature and pressure, so that the point-creviced substrate was completely immersed and kept in the liquid surface of the mildewcide solution for 30 minutes until it was saturated.

[0120] (6) : The point-creviced substrate impregnated with the mildewcide in step (5) was taken out and gently wiped with filter paper until no liquid drops fell down, weighed and calculated its drug loading as 0.04 kg / m 3 , and then naturally air-dried to 8% moisture content to obtain the drug-loaded product, ready for use.

[0121] (7) : The surface of the drug-loaded product obtained in step (6) is coated with a thin layer of isocyanate resin, and the isocyanate loading is 0.4%. The isocyanate is allowed to fully penetrate the microcrack structure at each point on the surface, and the isocyanate is cured by drying at 60°C for 6h to obtain a mold-resistant wood reconstituted material.

[0122] Comparative Example 1

[0123] (1) : A sample of Schisandra chinensis base material with dimensions of 50mm x 20mm x 20mm is selected, and the Schisandra chinensis base material is naturally air-dried at 20°C to a moisture content of 10%. The density of the dried Schisandra chinensis base material is 1.0g / cm 3 for standby;

[0124] (2) : 2.5g of a 6% by mass solution of iodine propargyl alcohol butyl carbamate is mixed with 97.5g of distilled water and stirred uniformly to obtain a mold inhibitor solution with a mass concentration of 0.15%;

[0125] (3) : The Schisandra chinensis base material of step (1) is immersed in the mold inhibitor solution of step (2) at normal temperature and pressure, so that the Schisandra chinensis base material is completely immersed and kept for 30 minutes below the liquid surface of the mold inhibitor solution until it is saturated.

[0126] (4) : The Schisandra chinensis base material immersed in the mold inhibitor of step (3) is taken out and gently wiped with filter paper until no liquid drops fall. It is weighed and the drug loading is calculated to be 0.03kg / m 3 . It is then naturally air-dried to a moisture content of 8% to obtain a drug-loaded product for standby.

[0127] (5) : The surface of the drug-loaded product obtained in step (4) is coated with a thin layer of isocyanate resin, and the isocyanate loading is 0.4%. The isocyanate is cured by drying at 60°C for 6h to obtain a mold-resistant wood reconstituted material by ordinary immersion method.

[0128] Comparative Example 2

[0129] (1) : A sample of Schisandra chinensis base material with dimensions of 50mm x 20mm x 20mm is selected and placed in a water bath at 75°C for 4h of water boiling pretreatment. The water-boiled Schisandra chinensis base material is air-dried indoors and then placed in an oven for drying until it is absolutely dry. It is then naturally air-dried indoors to adjust the moisture content to stable, reaching a moisture content of 10% and a density of 1.0g / cm 3 for standby;

[0130] (2) : 2.5g of a 6% by mass solution of iodine propargyl alcohol butyl carbamate is mixed with 97.5g of distilled water and stirred uniformly to obtain a mold inhibitor solution with a mass concentration of 0.15%;

[0131] (3) : At normal temperature and pressure, immerse the boiled Schleichera oleosa substrate of step (1) in the mildew-proofing agent solution of step (2) so that the boiled Schleichera oleosa substrate is completely immersed below the liquid surface of the mildew-proofing agent solution and kept for 30 minutes until the boiled Schleichera oleosa substrate is saturated with absorption;

[0132] (4) : Take out the mildew-proofing agent-impregnated boiled Schleichera oleosa substrate of step (3) and gently wipe it with filter paper until no liquid drops fall, weigh and calculate the drug loading amount as 0.038 kg / m 3 , and then naturally air dry to 8% moisture content to obtain a drug-loaded product for standby.

[0133] (5) : Brush a thin layer of isocyanate resin on the surface of the drug-loaded product obtained in step (4) with an isocyanate loading amount of 0.4%, and dry at 60°C for 6h until the isocyanate is cured to obtain a boiled pretreated mildew-proofing wood reconstituted material.

[0134] Comparative Example 3

[0135] (1) : Select a Schleichera oleosa substrate sample with a size of 50mm x 20mm x 20mm, adjust its moisture content to 30%-35%, and put it into a microwave oven with a power of 700w for 60 seconds, then take it out and naturally air dry indoors until stable to reach a moisture content of 8%, to obtain a microwave Schleichera oleosa substrate with a density of 1.0g / cm 3 , for standby;

[0136] (2) : Mix 2.5g of iodine propargyl alcohol butyl carbamate solution with a mass fraction of 6% with 97.5g of distilled water and stir uniformly to obtain a mildew-proofing agent solution with a mass concentration of 0.15%;

[0137] (3) : At normal temperature and pressure, immerse the microwave Schleichera oleosa substrate of step (1) in the mildew-proofing agent solution of step (2) so that the microwave Schleichera oleosa substrate is completely immersed below the liquid surface of the mildew-proofing agent solution and kept for 30 minutes until the microwave Schleichera oleosa substrate is saturated with absorption;

[0138] (4) : Take out the mildew-proofing agent-impregnated microwave Schleichera oleosa substrate sample of step (3) and gently wipe it with filter paper until no liquid drops fall, weigh and calculate the drug loading amount as 0.034 kg / m 3 , and then naturally air dry to 8% moisture content to obtain a drug-loaded product for standby.

[0139] (5) : Brush a thin layer of isocyanate resin on the surface of the drug-loaded product obtained in step (4) with an isocyanate loading amount of 0.4%, and dry at 60°C for 6h until the isocyanate is cured to obtain a microwave pretreated mildew-proofing wood reconstituted material.

[0140] Performance test

[0141] 1、Drug loading amount

[0142] The fungicide loading capacity of the wood reconstituted material was calculated by dividing the total mass of the fungicide to be tested by the volume of the wood reconstituted material (50 mm x 20 mm x 20 mm), and the results are shown in Table 1:

[0143] Table 1

[0144] Example / Comparative example Comparative example 1 Comparative example 2 Comparative example 3 Example 1 Example 2 Example 3 Drug loading amount / kg / m 3 ]]> 0.03 0.038 0.034 0.06 0.08 0.04

[0145] As can be seen from Table 1, the loading capacity in Examples 1-2 of the present application is higher than that in Comparative Examples 1-3, wherein the loading capacity of Example 1 is even twice that of Comparative Example 1, indicating that the point-creating micro-cracking method of the present application can create multi-scale permeation channels, effectively enhancing the permeability of the wood reconstituted material and increasing the loading capacity. In Example 3, the loading capacity is relatively low due to the low mass concentration of the fungicide.

[0146] 2. Mechanical property test

[0147] The static bending strength, elastic modulus and shear strength of the wood reconstituted material were obtained by using a universal mechanical testing machine (MWD-W10, Shandong Jinan Instrument Co., Ltd.), and the results are shown in Table 2:

[0148] Table 2

[0149]

[0150] As can be seen from Table 2, the wood reconstituted material of Examples 1-3 of the present application has higher static bending strength, elastic modulus and shear strength than Comparative Examples 1-3. The static bending strength, elastic modulus and shear strength of Example 1 are the best, which are increased by 27%, 24% and 43% respectively compared with Comparative Example 2, having obvious advantages. Therefore, the mechanical properties of the examples of the present application are excellent. The excellent mechanical properties are derived from the undamaged point-creating micro-cracking structure to the cell wall structure, which fills the pores of the wood reconstituted material and enhances the adhesion.

[0151] 3. Dimensional stability test

[0152] The wood reconstituted material sample (50 mm x 20 mm x 20 mm) was immersed in a constant temperature water tank with a pH value of 7±1 and a temperature of (63+3)℃. The surface of the wood reconstituted material sample was perpendicular to the horizontal plane. The wood reconstituted material samples were at least 15 mm apart from each other and from the bottom and wall of the water tank, and the upper end of the wood reconstituted material sample was (25+5) mm below the horizontal plane, so that it could freely expand. After the wood reconstituted material sample was immersed for 24 h or 15 min, the sample was taken out of the water, the water adhering to the surface of the wood reconstituted material sample was wiped off, and the sample was cooled for 10 min at room temperature for testing. The thickness and width of the sample were measured with an accuracy of 0.01 mm, and the thickness and width swelling rates were calculated.

[0153] Table 3

[0154] Example / Comparative example Comparative example 1 Comparative example 2 Comparative example 3 Example 1 Example 2 Example 3 Thickness expansion rate / % 9.8％ 11.4％ 10.0％ 6.0％ 6.4％ 6.1％ Width expansion rate / % 6.0％ 6.3％ 6.1％ 4.4％ 4.5％ 4.4％

[0155] As can be seen from Table 3, the wood restructured materials of Examples 1-3 of the present application have lower thickness expansion rate and width expansion rate than Comparative Examples 1-3. The thickness expansion rate and width expansion rate of Example 1 are reduced by 48% and 30% respectively compared with Comparative Example 2. Therefore, the wood restructured materials of the present application have excellent dimensional stability. The excellent dimensional stability of the present application is derived from the fact that the isocyanate penetrates into the intercellular layer, cell cavity and cell wall of the wood through the point of creation of microcracks, and the porosity is reduced after drying and curing, and the connection between the internal structures of the wood is more closely, so that the wood restructured material is not prone to shrinkage and swelling. At the same time, the isocyanate will react with the hydroxyl groups in the chemical components of the wood, reducing the number of hydroxyl groups and reducing its hydrophilicity, resisting the invasion of water, thereby inhibiting the deformation of the wood restructured material.

[0156] 4. Test of mildew resistance

[0157] The mildew detection was carried out according to the test method for the control efficiency of mildew and discoloration fungi of wood treated with fungicides in GB / T18261-2013. The mildew used was Aspergillus niger V.Tiegh and Lasiodiplodia theobromae. Before inoculation, the wood restructured material sample was wrapped with multiple layers of gauze, sterilized with 100℃ steam for 30min, and then inoculated after cooling. Under sterile conditions, 2 sterilized glass rods (diameter 3mm) were placed on the flat plate culture medium covered with mycelium, and then placed horizontally on the glass rods, 2 pieces of wood restructured material were placed in each culture dish. After inoculation, immediately put back into the incubator (maintain 25℃-28℃, relative humidity 85%), cultivate for 4 weeks, and visually observe the infection area of the wood restructured material. The surface infection value grading standard of the wood restructured material by Aspergillus niger and Lasiodiplodia theobromae is shown in Table 4, and the lower the infection value, the greater the drug efficacy.

[0158] Table 4

[0159] Infection value Infection area of sample 0 Sterile filament, mold point on surface of sample 1 Sample surface infection area <1 / 4 2 Infection area 1 / 4 to 1 / 2 on surface of sample 3 Infection area 1 / 2 to 3 / 4 on surface of sample 4 Infection area > 3 / 4 on surface of sample

[0160] The surface infection of the comparative example and example samples by Aspergillus niger and Lasiodiplodia theobromae is shown in Table 5: Figure 6

[0161] Table 5

[0162]

[0163] ​As can be seen from Table 5, the wood restructured material of Comparative Example 1 has a surface mycelium growth with an infection value of 1, while the wood restructured materials of Inventive Examples 1-3 have a damage value of 0, reaching a strong mildew-proof level. In combination with Figure 6 It can be more directly seen that the wood restructured material of Comparative Example 1 has white mycelium growth on the surface and side, and the blue mold has occupied 75% of the area, while the wood restructured materials of Inventive Examples 1-3 are not infected by any mildew, and exhibit very excellent mildew-proof properties at a very low concentration of the mildew-proof agent.

[0164] 5. Leaching rate test

[0165] The wood restructured materials of Inventive Examples 1-3 and Comparative Examples 1-3 are sawed into small wood pieces with a size of 20mm x 20mm x 20mm, 6 pieces are taken as a group, placed in a 500ml beaker, 180ml deionized water is added, the small wood piece sample is submerged below the deionized water surface, stirred with a stirrer, the deionized water is replaced every 6h, 24h, 48h, and then every 48h, for a total of 14 days. The filtrate collected each time is combined for drug loading analysis.

[0166] 200ml of the filtrate is taken out, concentrated by a rotary evaporator at 60°C for 2h, 2ml of chromatographic grade methanol is then used to dissolve the concentrated solid adhered to the inner wall of the glass, followed by ultrasonic treatment for 10min, to fully mix the concentrated solid with the methanol. The mixed solution is then added to a liquid chromatograph for detection of characteristic peaks, and the area of the chromatographic peak in the leaching liquid is calculated, to obtain the mass concentration of the mildew-proof agent of the small wood piece sample. The mass of the preservative to be tested in the leaching experiment filtrate of the small wood piece sample is obtained by using an Elite P230 high-performance liquid chromatograph produced by a Chinese company, divided by the total mass of the preservative to be tested of the small wood piece sample, to obtain the leaching rate of the mildew-proof agent, and the results are shown in Table 6.

[0167] Table 6

[0168]

[0169] As can be seen from Table 6, the leaching rates of the wood restructured materials of Comparative Examples 1-3 are 4.5%, 6.2%, and 4.6% respectively, indicating that the effect of the mildew-proof agent of the comparative examples will be easily lost under outdoor rainwater immersion and scouring conditions. The leaching rates of the wood restructured materials of Inventive Examples 1-3 are low, which can well resist the loss of effective components under outdoor and other harsh conditions, and maintain excellent mildew-proof effect.

[0170] It should be noted that although the technical solutions of the present application are described in specific examples, those skilled in the art can understand that the present application should not be limited thereto.

[0171] Having described various embodiments of the application, it is to be understood that the above description is meant not to limit and not to encompass all of the possible embodiments covered by the claims. Many modifications and variations of this application can be apparent to those of ordinary skill in the art without departing from the spirit and scope of the described embodiments. It is intended that the scope of the application should only be limited by the appended claims.

Claims

1. A wood-based reconstituted material, characterized in that, The surface and / or interior of the wood-based reconstituted material have an anti-mildew agent; and... The surface and / or interior of the wood-based reconstituted material have a pitted microcrack structure, which enables the surface and / or interior of the wood-based reconstituted material to have multi-scale permeation channels. The point-induced microcrack structure is formed by applying point-like external force; The wood-based reconstituted material has multiple cracks between the intercellular layers and on the cell walls, and the number of cracks on the cell walls is less than the number of cracks between the intercellular layers. The point-wound microcrack structure has pores, and the diameter of the pores in the point-wound microcrack structure is 0.5-3 mm; The distance from the surface of the wood-based reconstituted material to the interior of the pores in the point-cracked micro-crack structure is 0.5-3 mm. With the radial cross-sectional area of ​​the wood-based reconstituted material being 100%, the radial cross-sectional area of ​​the point-crack microcrack structure is 0.5-5%.

2. The wood-based reconstituted material according to claim 1, characterized in that, In the aforementioned wood-based reconstituted material, the loading of the antifungal agent is 0.02-0.1 kg / m³. 3 ; and / or The moisture content of the wood-based reconstituted material is 6-12%.

3. The wood-based reconstituted material according to claim 1 or 2, characterized in that, The antifungal agent contains one or more of the following: iodopropynyl butylcarbamate, quaternary ammonium copper, copper azole, isothiazolone, and titanium dioxide.

4. The wood-based reconstituted material according to claim 1 or 2, characterized in that, The outer surface of the wood-based reconstituted material also includes a finishing layer.

5. The wood-based reconstituted material according to claim 4, characterized in that, The finishing layer is derived from thermosetting resin.

6. The wood-based reconstituted material according to claim 5, characterized in that, The thermosetting resin includes isocyanate.

7. A method for preparing a wood-based reconstituted material according to any one of claims 1-6, characterized in that, Includes the following steps: Obtain a substrate material derived from wood and / or bamboo materials; A point-cracked microcrack structure is formed on the surface and / or interior of the substrate, resulting in multi-scale permeation channels on the surface and / or interior of the substrate; and multiple cracks are present between the intercellular layers and on the cell walls of the substrate, with fewer cracks on the cell walls than between the intercellular layers, thus obtaining a point-cracked microcrack substrate. The microcracked substrate is impregnated with an antifungal agent solution to obtain a wood-based reconstituted material.

8. The preparation method according to claim 7, characterized in that, The moisture content of the substrate is 5-15%; and / or, A point-crack micro-crack device is used to apply vertical pressure to the substrate, causing point-crack micro-crack structures to be generated on the surface and / or inside of the substrate, forming a point-crack micro-crack structure network.

9. The preparation method according to claim 8, characterized in that, The vertical pressure is 1.8-2.2 MPa.

10. The preparation method according to any one of claims 7-9, characterized in that, The antifungal agent solution contains an antifungal agent with a mass concentration of 0.05-0.5%; and / or The immersion time is 5-60 minutes.

11. The preparation method according to any one of claims 7-9, characterized in that, It also includes the step of finishing the wood-based reconstituted material with a thermosetting resin.

12. The preparation method according to claim 11, characterized in that, The thermosetting resin includes isocyanate.

13. The preparation method according to claim 11, characterized in that, Based on the total mass of the wood-based reconstituted material being 100%, the loading of the thermosetting resin is 0.3-0.6%.

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