Mixed artificial board and preparation method and application thereof

Abstract

The invention discloses a mixed artificial board and a preparation method and application thereof. The number of layers of the mixed type artificial boards is odd, the wood veneer serves as a core layer of a symmetry center plane, and the layers on the two sides of the symmetry center plane correspond to each other. The structural units of the plates of the layers on the two sides of the symmetric center plane are veneers, wood shavings, particles or fibers, and the adjacent layers are selected from different types of structural units. According to the artificial board, the product adaptability and the product performance are improved, the production method is high in production efficiency, the application field of the artificial board is particularly expanded, and the technical problem that continuous and automatic production of traditional plywood is difficult to achieve is particularly solved.

Description

Technical Field

[0001] The invention relates to the technical field of wood processing and production, and in particular to a mixed artificial board and a preparation method and application thereof. Background Art

[0003] At present, there are about 10,100 wood-based panel enterprises in my country, with an annual production capacity of about 335 million cubic meters. The production and consumption of wood-based panels are ranked first in the world. Among them, plywood accounts for about 60% of wood-based panels and is the main variety of wood-based panel products in my country. As the veneer is used as the structural unit, plywood not only retains the porous characteristics of wood, but also has significantly better mechanical properties than particleboard and medium-density fiberboard due to the cross-matching of wood texture during the paving process. However, my country's plywood industry is dominated by small and medium-sized enterprises, and generally adopts intermittent or cyclic production processes. It is still a labor-intensive industry with low production efficiency. The aging and pre-pressing processes of veneers after gluing cause process stagnation and increase the difficulty of the process. How to improve the plywood production method through production mode upgrade is a technical problem that the plywood industry needs to solve urgently.

[0004] In recent years, my country's particleboard and medium-density fiberboard industry has upgraded intermittent or periodic production technology with continuous flat-pressing production technology, thereby improving production efficiency. However, during the manufacturing process of particleboard and medium-density fiberboard, the structural unit size is small and the overall mechanical properties of the board are not high. At the same time, due to the use of oriented paving technology, the parallel (or longitudinal) static bending strength of the board is improved, but the vertical (or transverse) strength is still relatively low.

[0005] Creating new structural wood-based panels through technological innovation and improving the performance and production efficiency of wood-based panels by integrating the advantages of various wood-based panels’ performance and production methods have always been the goals pursued by my country’s wood-based panel industry.

[0006] Authorized invention patent ZL02134156.7 "Three-layer structure wood composite board and its manufacturing method" was the first to propose the use of large wood chips in the core layer and fiber or particle structural units on the surface, aiming to balance the surface quality and mechanical properties such as static bending strength; invention patent application 201711302868.7 "Oriented Strand Board and Oriented Wood-Based Panel" is similar to the aforementioned authorized patents, involving an oriented strand board and oriented wood-based panel with a higher surface fineness, but these patents did not solve the technical problem of improving the low transverse static bending strength of particleboard. Authorized invention patent ZL202310313019.0 "An ENF-grade bamboo-wood composite hybrid artificial board and continuous flat pressing manufacturing method" and invention patent application CN116674040A "A paper-faced hybrid artificial board for building partitions and its production method" provide mixed artificial boards of different materials and mixed artificial boards with artificial board products as structural units and their production methods, wherein the core layer is particleboard or fiberboard, and the technical features are phased paving and phased hot pressing, but these technical solutions do not solve the technical difficulties of continuous and automated production of single-board artificial boards such as plywood. Summary of the invention

[0007] In view of this, the main purpose of the present invention is to provide a hybrid artificial board and a preparation method and application thereof, in order to at least partially solve the above technical problems.

[0008] In order to achieve the above-mentioned purpose, as the first aspect of the present invention, a hybrid artificial board is provided, which has an odd number of layers (preferably 3-7 layers), with a wooden veneer as the core layer of the central plane of symmetry, and the layers on both sides of the central plane of symmetry correspond to each other; it should be noted that the correspondence includes the species, fiber direction, thickness, number of layers, manufacturing method, moisture content, etc. of the wooden veneer are all corresponding; the artificial board with an odd number of layers can ensure that the central plane of symmetry is in the core layer, which can ensure the strength.

[0009] The structural units of the layers on both sides of the central plane of symmetry are wood veneers, wood chips, particles or fibers, and the adjacent layers are selected from different types of structural units;

[0010] In the hybrid artificial board, the texture of the wood veneer is arranged along the length direction perpendicular to the hybrid artificial board; the texture or fiber of other types of boards forms an angle of 60°-90° with the texture of the wood veneer; the texture or fiber of the other types of structural units forms an angle of 60°-90° with the texture of the wood veneer; and / or the texture or fiber of the other types of structural units forms an angle of 90° with the texture of the wood veneer, which can ensure that the mechanical strength of the hybrid artificial board of the present invention in all directions is basically consistent and a certain strength level is guaranteed.

[0011] Different types of structural units are arranged adjacently, and the textures are at a certain angle, which can ensure that the tensile strength in all directions is basically consistent; in particular, the texture of the wood veneer is arranged along the vertical length direction, which can improve the transverse mechanical properties of the product. It is also possible to adjust the proportion of different types of boards to ensure that the prepared artificial board meets the requirements of different mechanical properties.

[0012] The wooden veneer is spliced ​​along the length direction of the hybrid artificial board, and the structural units of other types are continuous structures; the difficulty of using continuous flat pressing production technology for veneer artificial boards such as plywood lies in the continuous splicing of veneers, especially the continuous splicing along the wood grain direction, while transverse splicing can achieve large-scale continuous production. Therefore, the present invention proposes that both the core layer and the inner surface layer use transversely spliced ​​veneers, while other layers use shavings, fibers or particles for continuous paving and hot pressing, which greatly reduces the difficulty of subsequent continuous paving and continuous hot pressing production technology.

[0013] Preferably, the number of layers of the wooden veneer is 1-5, preferably 1-3.

[0014] Preferably, the thickness of the wood veneer of the core layer is 1-4.5mm (for example, it can be 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, .7mm, 3.8mm, 3.9mm, 4.0mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm or any value within the range, which is not described in detail due to space limitations), preferably 1.0-3.0mm, and is greater than or equal to the thickness of the wood veneer of other layers.

[0015] Preferably, the length of the shavings is 50-200 mm (for example, it can be 50 mm, 60 mm, 70 mm, 80 mm, 90 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm or any value within the range, which will not be described in detail due to space limitations), the thickness of the shavings is 0.2-1.2 mm (for example, it can be 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm or any value within the range, which will not be described in detail due to space limitations), and the arrangement of the shavings is random arrangement and / or directional arrangement;

[0016] The wood shavings layer is formed by bonding wood shavings with an adhesive, wherein the adhesive is selected from: formaldehyde series resins, isocyanate resins, glyceryl polyurethane resins or biomass resins;

[0017] The formaldehyde series resin is selected from: urea-formaldehyde resin, modified urea-formaldehyde resin or phenol-formaldehyde resin.

[0018] Preferably, the particle layer or fiber layer of the hybrid artificial board is bonded by an adhesive;

[0019] The adhesive is selected from: formaldehyde series resin, isocyanate resin, glycerol-based polyurethane resin or biomass resin;

[0020] The formaldehyde series resin is selected from: urea-formaldehyde resin, modified urea-formaldehyde resin or phenol-formaldehyde resin.

[0021] Preferably, the splicing method of the wooden veneer is selected from: glue thread splicing, tape splicing, non-woven fabric splicing or grinding overlap.

[0022] Preferably, the glyceryl polyurethane resin adhesive comprises the following components:

[0023] Highly branched glycerol polyester polyol prepolymer

[0024] Polyurethane prepolymer with NCO terminal group;

[0025] The OH / NCO molar ratio of the two components is 0.8-1.2 (the molar ratio can be, for example, 0.8, 0.9, 1.0, 1.1, 1.2 or any value within the range, which will not be described in detail due to space limitations).

[0026] The preparation method of the glycerol-based polyurethane resin adhesive comprises: uniformly mixing a highly branched glycerol polyester polyol prepolymer and a polyurethane prepolymer with an NCO terminal group at room temperature to obtain the glycerol-based polyurethane resin adhesive.

[0027] Preferably, the preparation method of the highly branched glycerol polyester polyol prepolymer is as follows:

[0028] (1) adding 100 parts by weight of glycerol into a reaction kettle and stirring;

[0029] (2) gradually adding maleic anhydride dropwise to glycerol with stirring, and controlling the glycerol / maleic anhydride molar ratio to be 0.9-1.1;

[0030] (3) adding 100 parts by weight of maleic anhydride into a reaction kettle and stirring;

[0031] (4) gradually adding a certain amount of glycerol dropwise into the reaction kettle, controlling the maleic anhydride / glycerol molar ratio to be 3.0-3.1;

[0032] (5) heating the mixture to 140-145° C. and maintaining the temperature for at least 3 hours, and cooling the mixture to obtain a highly branched glycerol polyester polyol prepolymer;

[0033] The preparation method of the polyurethane prepolymer with NCO terminal group is as follows:

[0034] (1) adding 100 parts by weight of an isocyanate compound into a reaction kettle and stirring; the isocyanate compound includes: TDI, PAPI or MDI;

[0035] (2) adding 10-50 parts by weight of highly branched glycerol polyester polyol prepolymer or trimethylolpropane dropwise into a reaction kettle and stirring;

[0036] (3) After the reaction is completed, the product is cooled to room temperature to obtain the polyurethane prepolymer with NCO terminal groups.

[0037] Preferably, the preparation method of the highly branched glycerol polyester polyol prepolymer is as follows:

[0038] (1) adding 100 parts by weight of glycerol into a reaction kettle, stirring for 20 minutes and heating to 60-80° C. (for example, it can be 60° C., 61° C., 62° C., 63° C., 64° C., 65° C., 66° C., 67° C., 68° C., 69° C., 70° C., 71° C., 72° C., 73° C., 74° C., 75° C., 76° C., 77° C., 78° C., 79° C., 80° C. or any value within the range, which will not be described in detail due to space limitations);

[0039] (2) gradually adding maleic anhydride dropwise to glycerol, and continuing to raise the temperature to 80-100° C. (for example, 80° C., 81° C., 82° C., 83° C., 84° C., 85° C., 86° C., 87° C., 88° C., 89° C., 90° C., 91° C., 92° C., 93° C., 94° C., 95° C., 96° C., 97° C., 98° C., 99° C., 100° C. or any value within the range, which will not be described in detail due to space limitations), controlling the glycerol temperature to be 100° C.; The oil / maleic anhydride molar ratio is 0.9-1.1 (the molar ratio can be 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 1.0, 1.01, 1.02, 1.03, 1.04, 1.05, 1.06, 1.07, 1.08, 1.09, 1.1 or any value within the range, which will not be described in detail due to space limitations);

[0040] (3) adding 100 parts by weight of maleic anhydride into a reaction kettle, stirring and cooling to 60-80° C. (for example, it can be 60° C., 61° C., 62° C., 63° C., 64° C., 65° C., 66° C., 67° C., 68° C., 69° C., 70° C., 71° C., 72° C., 73° C., 74° C., 75° C., 76° C., 77° C., 78° C., 79° C., 80° C. or any value within the range, which will not be described in detail due to space limitations);

[0041] (4) gradually adding a certain amount of glycerol dropwise into the reaction kettle, controlling the maleic anhydride / glycerol molar ratio to be 3.0-3.1 (the molar ratio may be 3.01, 3.02, 3.03, 3.04, 3.05, 3.06, 3.07, 3.08, 3.09, 3.1 or any value within the range, which will not be described in detail due to space limitations), and maintaining the reaction temperature to be 80-100° C. (for example, it may be 80° C., 81° C., 82° C., 83° C., 84° C., 85° C., 86° C., 87° C., 88° C., 89° C., 90° C., 91° C., 92° C., 93° C., 94° C., 95° C., 96° C., 97° C., 98° C., 99° C., 100° C. or any value within the range, which will not be described in detail due to space limitations);

[0042] (5) heating the mixture to 140-145° C. (for example, 140° C., 140.5° C., 141° C., 141.5° C., 142° C., 142.5° C., 143° C., 143.5° C., 144° C., 144.5° C., 145° C. or any value within the range, which will not be described in detail due to space limitations) and keeping the temperature for at least 3 hours, and cooling the mixture to obtain a highly branched glycerol polyester polyol prepolymer.

[0043] Preferably, the preparation method of the polyurethane prepolymer having an NCO terminal group is as follows:

[0044] (1) adding 100 parts by weight of an isocyanate compound into a reaction kettle, stirring and heating to 40-60° C. (for example, 40° C., 41° C., 42° C., 43° C., 44° C., 45° C., 46° C., 47° C., 48° C., 49° C., 50° C., 51° C., 52° C., 53° C., 54° C., 55° C., 56° C., 57° C., 58° C., 59° C., 60° C. or any value within the range, which will not be described in detail due to space limitations); the isocyanate compound includes: TDI, PAPI or MDI;

[0045] (2) 10-50 parts by weight (for example, 10 parts by weight, 15 parts by weight, 20 parts by weight, 25 parts by weight, 30 parts by weight, 35 parts by weight, 40 parts by weight, 45 parts by weight, 50 parts by weight or any value within the range, which will not be described in detail due to space limitations) of highly branched glycerol polyester polyol prepolymer or trimethylolpropane is added dropwise to a reaction kettle, and the temperature is raised to 65-70° C. and stirred for reaction;

[0046] (3) After the reaction is completed, the product is cooled to room temperature to obtain the polyurethane prepolymer with NCO terminal groups.

[0047] In a second aspect of the present invention, a method for preparing the hybrid artificial board according to the first aspect is provided, the method comprising the following steps:

[0048] (1) Laying wooden veneers continuously and splicing them into a continuous state, and spraying and / or pouring adhesive on the surface of the wooden veneers;

[0049] (2) obtaining a continuous particleboard, particleboard and / or fiberboard according to the production process of particleboard, particleboard or fiberboard;

[0050] (3) Continuously laying wood veneer, particle board, particle board and / or fiber board on both sides of the core layer by continuous laying;

[0051] (4) The paved slab is continuously pre-pressed, preheated and hot-pressed to obtain a hybrid artificial board.

[0052] Preferably, the layers are laid one by one in sequence.

[0053] Preferably, in step (1), the amount of glue applied on one side of the wood veneer is 150-300 g / mm 2 (For example, it can be 150g / mm 2 , 160g / mm 2 , 170g / mm 2 , 180g / mm 2 , 190g / mm 2 , 200g / mm 2 , 210g / mm 2 , 220g / mm 2 , 230g / mm 2 , 240g / mm 2 , 250g / mm 2 , 260g / mm 2 , 270g / mm 2 , 280g / mm 2 , 290g / mm 2 , 300g / mm 2 or any value within the range, which will not be described in detail due to space limitations); and / or

[0054] Use roller coater, glue sprayer or glue sprayer to apply glue.

[0055] Preferably, in step (2), the method for preparing the particleboard blank comprises: uniformly mixing the adhesive and the particles, and then continuously paving them into the particleboard blank.

[0056] Preferably, the method for preparing the particle slab comprises: uniformly mixing the adhesive and particles, and then continuously paving them into the particle slab.

[0057] Preferably, the method for preparing the fiber mat comprises: mixing the adhesive with the separated wet fibers at the outlet of the hot mill, drying to a specified moisture content, and then continuously laying the fibers into the fiber mat.

[0058] Preferably, in step (4), the continuous pre-pressing pressure is 3.0-6.0 MPa (for example, it can be 3.0 MPa, 3.2 MPa, 3.4 MPa, 3.6 MPa, 3.8 MPa, 4.0 MPa, 4.2 MPa, 4.4 MPa, 4.6 MPa, 4.8 MPa, 5.0 MPa, 5.2 MPa, 5.4 MPa, 5.6 MPa, 5.8 MPa, 6.0 MPa or any value within the range, which will not be described in detail due to space limitations); and / or

[0059] The preheating step specifically includes: preheating the particle layer board to 65-85°C (for example, 65°C, 66°C, 67°C, 68°C, 69°C, 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, 76°C, 77°C, 78°C, 79°C, 80°C, 81°C, 82°C, 83°C, 84°C, 85°C or any value within the range, which is not described in detail due to space limitations) within 20-60s (for example, 20s, 22s, 24s, 26s, 28s, 30s, 32s, 34s, 36s, 38s, 40s, 42s, 44s, 46s, 48s, 50s, 52s, 54s, 56s, 58s, 60s or any value within the range, which is not described in detail due to space limitations); and / or

[0060] The hot pressing is performed using a continuous flat press; and / or

[0061] The hot pressing factor of the hot pressing is 5-15s / mm (for example, it can be 5s / mm, 6s / mm, 7s / mm, 8s / mm, 9s / mm, 10s / mm, 11s / mm, 12s / mm, 13s / mm, 14s / mm, 15s / mm or any value within the range, which will not be repeated due to space limitations).

[0062] The preparation method of the hybrid artificial board provided by the present invention achieves the purpose of improving production efficiency by integrating continuous paving and continuous flat pressing production technologies. The key to achieving continuous flat pressing production lies in the continuous paving of slabs other than wood veneers. The present invention continuously paves layer by layer along the direction of travel of the production line, and in particular, the innovative invention centers on the transverse paving of the core layer veneer, and the grains of adjacent layers of wood intersect with each other, thus overcoming the technical difficulty that veneer artificial boards cannot achieve continuous production.

[0063] In order to further improve production efficiency, the present invention adds a preheating process after paving is completed, which accelerates the curing of the resin adhesive by quickly increasing the temperature of the core layer of the slab, thereby shortening the hot pressing time and improving production efficiency.

[0064] In the third aspect of the present invention, there is provided the use of the hybrid artificial board as described in the first aspect in the field of house construction and decoration.

[0065] Based on the above technical solution, it can be seen that the hybrid artificial board and its preparation method and application of the present invention have at least one of the following beneficial effects compared with the prior art:

[0066] 1) The present invention creates a new type of structural artificial board through structural unit reorganization: The present invention enriches the variety of artificial board products in my country through the optimization and reorganization of multiple structural units. Compared with ordinary particleboard and oriented particleboard, the transverse static bending strength is significantly improved, and compared with plywood, the production efficiency is significantly improved, and finally the adaptability of artificial board products is improved to meet the mechanical and dimensional stability requirements of artificial boards in different application fields, which is helpful for artificial boards to expand the application market, especially in the construction field.

[0067] 2) Provides a technical route for the continuous and automated production of veneer-type artificial boards: The present invention integrates the production of veneer-type artificial boards with the production technologies of particleboard (including oriented strand board) and medium-density fiberboard, which helps to solve the technical difficulties of the difficulty of continuous and automated production of veneer-type artificial boards and low production efficiency. The method of the present invention is integrated with the existing continuous flat-pressing production technology, without changing the basic production equipment and basic production process flow of the existing continuous flat-pressing production line. It only needs to add appropriate equipment, which is convenient for the transformation and upgrading of the existing production line.

[0068] 3) The present invention uses large-sized single-board structural units, which is beneficial to reducing the amount of adhesive used, which is beneficial to reducing manufacturing costs and reducing formaldehyde emissions from artificial boards, thereby further improving the environmental protection level of artificial boards.

[0069] 4) The preheating technology in the present invention can speed up the heating speed of the core layer of the slab and accelerate the curing of the resin adhesive, which is helpful to further improve the production efficiency of the entire line. In addition, the method of the present invention is applicable to various adhesives and can meet the requirements of environmental protection and mechanical properties at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 It is a schematic diagram of the preparation method of the hybrid artificial board provided by the present invention. DETAILED DESCRIPTION

[0071] The performance of the artificial board in the prior art is poor, and the production efficiency is low. In particular, the technical problem of low transverse static bending strength of the artificial board has not been overcome, and continuous automated production cannot be achieved. After intensive research, the inventors of the present invention have improved the above steps and the structure of the artificial board, thereby obtaining a hybrid artificial board with better mechanical properties and continuous automated production. Specifically, as a first aspect of the present invention, a hybrid artificial board is provided, wherein the number of layers of the hybrid artificial board is an odd number of layers (preferably 3-7 layers), with a wood veneer as the core layer of the symmetry center plane, and the layers on both sides of the symmetry center plane correspond to each other; it should be noted that the correspondence includes the species, fiber direction, thickness, number of layers, manufacturing method, moisture content, etc. of the wood veneer are all corresponding; the artificial board with an odd number of layers can ensure that the symmetry center plane is in the core layer, and the strength can be guaranteed.

[0072] The structural units of the layers on both sides of the central plane of symmetry are selected from wood veneers, wood chips, particles or fibers, and the adjacent layers are selected from different types of boards;

[0073] In the hybrid artificial board, the texture of the wood veneer is arranged along the length direction perpendicular to the hybrid artificial board; the texture or fiber of other types of boards forms an angle of 60-90° with the texture of the wood veneer, which can ensure that the mechanical strength of the hybrid artificial board of the present invention in all directions is basically consistent and a certain strength level is guaranteed.

[0074] Different types of boards are arranged adjacently, and the textures are at a certain angle, which can ensure that the tensile strength in all directions is basically consistent; in particular, the texture of the wood veneer is set along the length direction, which can improve the mechanical properties of the product. It is also possible to adjust the proportion of different types of boards to ensure that the prepared artificial board meets the requirements of different mechanical properties.

[0075] The wooden veneer is spliced ​​along the length direction of the hybrid artificial board, and other types of boards are continuous structures; the difficulty of using continuous flat pressing production technology for veneer artificial boards such as plywood lies in the continuous splicing of veneers, especially the continuous splicing along the wood grain direction, while transverse splicing can achieve large-scale continuous production. Therefore, the present invention proposes that both the core layer and the inner surface layer use transversely spliced ​​veneers, while other layers use shavings, fibers or particles for continuous paving and hot pressing, which greatly reduces the difficulty of subsequent continuous paving and continuous hot pressing production technology.

[0076] In a preferred embodiment, the total thickness of the wood veneer accounts for 10%-60% of the total thickness of the hybrid wood-based panel (for example, it can be 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60% or any value within the range, which will not be described due to space limitations), preferably 30%-50%;

[0077] In a preferred embodiment, the number of layers of the wooden veneer is 1-5, for example, it can be 1 layer, 3 layers or 5 layers.

[0078] In a preferred embodiment, the thickness of the wood veneer of the core layer is 1.0-4.5mm (for example, it can be 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, .7mm, 3.8mm, 3.9mm, 4.0mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm or any value within the range, which is not described in detail due to space limitations), preferably 1.0-3.0mm, and is greater than or equal to the thickness of the wood veneer of other layers.

[0079] In a preferred embodiment, in the particleboard, the particle length is 50-200mm (for example, it can be 50mm, 60mm, 70mm, 80mm, 90mm, 100mm, 110mm, 120mm, 130mm, 140mm, 150mm, 160mm, 170mm, 180mm, 190mm, 200mm or any value within the range, which will not be described due to space limitations), the particle thickness is 0.2-1.2mm (for example, it can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm or any value within the range, which will not be described due to space limitations), and the particle arrangement is random arrangement and / or directional arrangement;

[0080] The particle board is made of wood particles bonded by an adhesive, and the adhesive is selected from: formaldehyde series resin, isocyanate resin, glycerol polyurethane resin or biomass resin;

[0081] The formaldehyde series resin is selected from: urea-formaldehyde resin, modified urea-formaldehyde resin or phenol-formaldehyde resin.

[0082] In a preferred embodiment, the layers of the hybrid wood-based panel are bonded by an adhesive;

[0083] The adhesive is selected from: formaldehyde series resin, isocyanate resin, glycerol polyurethane resin or biomass resin;

[0084] In a preferred embodiment, the formaldehyde series resin is selected from: urea-formaldehyde resin, modified urea-formaldehyde resin or phenol-formaldehyde resin.

[0085] In a preferred embodiment, the splicing method of the wooden veneer is selected from: glue line splicing, tape splicing, non-woven fabric splicing or grinding overlap.

[0086] In a preferred embodiment, the glyceryl polyurethane resin adhesive comprises the following components:

[0087] Highly branched glycerol polyester polyol prepolymer

[0088] Polyurethane prepolymer with NCO terminal group;

[0089] The OH / NCO molar ratio of the two components is 0.8-1.2 (the molar ratio can be 0.8, 0.9, 1.0, 1.1, 1.2 or all values ​​within the range, which will not be described in detail due to space limitations).

[0090] The preparation method of the glycerol-based polyurethane resin adhesive comprises the following steps: uniformly mixing a highly branched glycerol polyester polyol prepolymer and a polyurethane prepolymer with an NCO terminal group at room temperature to obtain the glycerol-based polyurethane resin adhesive.

[0091] In a preferred embodiment, the preparation method of the highly branched glycerol polyester polyol prepolymer is as follows:

[0092] (1) adding 100 parts by weight of glycerol into a reaction kettle and stirring;

[0093] (2) gradually adding maleic anhydride dropwise to glycerol with stirring, and controlling the glycerol / maleic anhydride molar ratio to be 0.9-1.1;

[0094] (3) adding 100 parts by weight of maleic anhydride into a reaction kettle and stirring;

[0095] (4) gradually adding a certain amount of glycerol dropwise into the reaction kettle, controlling the maleic anhydride / glycerol molar ratio to be 3.0-3.1;

[0096] (5) heating the mixture to 140-145° C. and maintaining the temperature for at least 3 hours, and cooling the mixture to obtain a highly branched glycerol polyester polyol prepolymer;

[0097] The preparation method of the polyurethane prepolymer with NCO terminal group is as follows:

[0098] (1) adding 100 parts by weight of an isocyanate compound into a reaction kettle and stirring; the isocyanate compound includes: TDI, PAPI or MDI;

[0099] (2) adding 10-50 parts by weight of highly branched glycerol polyester polyol prepolymer or trimethylolpropane dropwise into a reaction kettle and stirring;

[0100] (3) After the reaction is completed, the product is cooled to room temperature to obtain the polyurethane prepolymer with NCO terminal groups.

[0101] In a preferred embodiment, the preparation method of the highly branched glycerol polyester polyol prepolymer is as follows:

[0102] (1) adding 100 parts by weight of glycerol into a reaction kettle, stirring for 20 minutes and heating to 60-80° C. (for example, it can be 60° C., 61° C., 62° C., 63° C., 64° C., 65° C., 66° C., 67° C., 68° C., 69° C., 70° C., 71° C., 72° C., 73° C., 74° C., 75° C., 76° C., 77° C., 78° C., 79° C., 80° C. or any value within the range, which will not be described in detail due to space limitations);

[0103] (2) gradually adding maleic anhydride dropwise to glycerol, and continuing to raise the temperature to 80-100° C. (for example, 80° C., 81° C., 82° C., 83° C., 84° C., 85° C., 86° C., 87° C., 88° C., 89° C., 90° C., 91° C., 92° C., 93° C., 94° C., 95° C., 96° C., 97° C., 98° C., 99° C., 100° C. or any value within the range, which will not be described in detail due to space limitations), controlling the glycerol temperature to be 100° C.; The oil / maleic anhydride molar ratio is 0.9-1.1 (the molar ratio can be 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 1.0, 1.01, 1.02, 1.03, 1.04, 1.05, 1.06, 1.07, 1.08, 1.09, 1.1 or any value within the range, which will not be described in detail due to space limitations);

[0104] (3) adding 100 parts by weight of maleic anhydride into a reaction kettle, stirring and cooling to 60-80° C. (for example, it can be 60° C., 61° C., 62° C., 63° C., 64° C., 65° C., 66° C., 67° C., 68° C., 69° C., 70° C., 71° C., 72° C., 73° C., 74° C., 75° C., 76° C., 77° C., 78° C., 79° C., 80° C. or any value within the range, which will not be described in detail due to space limitations);

[0105] (4) gradually adding a certain amount of glycerol dropwise into the reaction kettle, controlling the maleic anhydride / glycerol molar ratio to be 3.0-3.1 (the molar ratio may be 3.01, 3.02, 3.03, 3.04, 3.05, 3.06, 3.07, 3.08, 3.09, 3.1 or any value within the range, which will not be described in detail due to space limitations), and maintaining the reaction temperature to be 80-100° C. (for example, it may be 80° C., 81° C., 82° C., 83° C., 84° C., 85° C., 86° C., 87° C., 88° C., 89° C., 90° C., 91° C., 92° C., 93° C., 94° C., 95° C., 96° C., 97° C., 98° C., 99° C., 100° C. or any value within the range, which will not be described in detail due to space limitations);

[0106] (5) heating the mixture to 140-145° C. (for example, 140° C., 140.5° C., 141° C., 141.5° C., 142° C., 142.5° C., 143° C., 143.5° C., 144° C., 144.5° C., 145° C. or any value within the range, which will not be described in detail due to space limitations) and keeping the temperature for at least 3 hours, and cooling the mixture to obtain a highly branched glycerol polyester polyol prepolymer.

[0107] In a preferred embodiment, the preparation method of the polyurethane prepolymer having an NCO terminal group is as follows:

[0108] (1) adding 100 parts by weight of an isocyanate compound into a reaction kettle, stirring and heating to 40-60° C. (for example, 40° C., 41° C., 42° C., 43° C., 44° C., 45° C., 46° C., 47° C., 48° C., 49° C., 50° C., 51° C., 52° C., 53° C., 54° C., 55° C., 56° C., 57° C., 58° C., 59° C., 60° C. or any value within the range, which will not be described in detail due to space limitations); the isocyanate compound includes: TDI, PAPI or MDI;

[0109] (2) 10-50 parts by weight (for example, 10 parts by weight, 15 parts by weight, 20 parts by weight, 25 parts by weight, 30 parts by weight, 35 parts by weight, 40 parts by weight, 45 parts by weight, 50 parts by weight or any value within the range, which will not be described in detail due to space limitations) of highly branched glycerol polyester polyol prepolymer or trimethylolpropane is added dropwise to a reaction kettle, and the temperature is raised to 65-70° C. and stirred for reaction;

[0110] (3) After the reaction is completed, the product is cooled to room temperature to obtain the polyurethane prepolymer with NCO terminal groups.

[0111] In a second aspect of the present invention, a method for preparing the hybrid artificial board according to the first aspect is provided, the method comprising the following steps:

[0112] (1) Laying wooden veneers continuously and splicing them into a continuous state, and spraying and / or pouring adhesive on the surface of the wooden veneers;

[0113] (2) using the wood chips, particles or fibers to obtain a continuous particle board, particle board and / or fiber board according to the production process of particle board, particle board or fiber board;

[0114] (3) Continuously laying wood veneer, particle board, particle board and / or fiber board on both sides of the core layer by continuous laying;

[0115] (4) The paved slab is continuously pre-pressed, preheated and hot-pressed to obtain a hybrid artificial board.

[0116] In a preferred embodiment, the layers are laid one by one in sequence.

[0117] In a preferred embodiment, in step (1), the amount of glue applied on one side of the wood veneer is 150-300 g / mm 2 (For example, it can be 150g / mm 2 , 160g / mm 2 , 170g / mm 2 , 180g / mm 2 , 190g / mm 2 , 200g / mm 2 , 210g / mm 2 , 220g / mm 2 , 230g / mm 2 , 240g / mm 2 , 250g / mm 2 , 260g / mm 2 , 270g / mm 2 , 280g / mm 2 , 290g / mm 2 , 300g / mm 2 or any value within the range, which will not be described in detail due to space limitations); and / or

[0118] Use a roller coater to apply the glue.

[0119] In a preferred embodiment, in step (2), the method for preparing the particleboard blank comprises: uniformly mixing the adhesive and the particles, and then continuously paving the particles into the particleboard blank;

[0120] In a preferred embodiment, the method for preparing the particle slab comprises: uniformly mixing the adhesive and particles, and then continuously paving the particles into the particle slab;

[0121] In a preferred embodiment, the method for preparing the fiber mat comprises: mixing the adhesive with the separated wet fibers at the outlet of the hot mill, drying to a specified moisture content, and then continuously laying the fibers into the fiber mat.

[0122] In a preferred embodiment, in step (4), the continuous pre-pressing pressure is 3.0-6.0 MPa (for example, it can be 3.0 MPa, 3.2 MPa, 3.4 MPa, 3.6 MPa, 3.8 MPa, 4.0 MPa, 4.2 MPa, 4.4 MPa, 4.6 MPa, 4.8 MPa, 5.0 MPa, 5.2 MPa, 5.4 MPa, 5.6 MPa, 5.8 MPa, 6.0 MPa or any value within the range, which will not be described in detail due to space limitations); and / or

[0123] The preheating step specifically includes: preheating the particle layer board to 65-85°C (for example, 65°C, 66°C, 67°C, 68°C, 69°C, 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, 76°C, 77°C, 78°C, 79°C, 80°C, 81°C, 82°C, 83°C, 84°C, 85°C or any value within the range, which is not described in detail due to space limitations) within 20-60s (for example, 20s, 22s, 24s, 26s, 28s, 30s, 32s, 34s, 36s, 38s, 40s, 42s, 44s, 46s, 48s, 50s, 52s, 54s, 56s, 58s, 60s or any value within the range, which is not described in detail due to space limitations); and / or

[0124] The hot pressing is performed using a continuous flat press; and / or

[0125] The hot pressing factor of the hot pressing is 5-15s / mm (for example, it can be 5s / mm, 6s / mm, 7s / mm, 8s / mm, 9s / mm, 10s / mm, 11s / mm, 12s / mm, 13s / mm, 14s / mm, 15s / mm or any value within the range, which will not be repeated due to space limitations).

[0126] The preparation method of the hybrid artificial board provided by the present invention achieves the purpose of improving production efficiency by integrating continuous paving and continuous flat pressing production technologies. The key to achieving continuous flat pressing production lies in the continuous paving of slabs other than wood veneers. The present invention continuously paves layer by layer along the direction of travel of the production line, and in particular, the innovative invention centers on the transverse paving of the core layer veneer, and the grains of adjacent layers of wood intersect with each other, thus overcoming the technical difficulty that veneer artificial boards cannot achieve continuous production.

[0127] In order to further improve production efficiency, the present invention adds a preheating process after paving is completed, which accelerates the curing of the resin adhesive by quickly increasing the temperature of the core layer of the slab, thereby shortening the hot pressing time and improving production efficiency.

[0128] In the third aspect of the present invention, there is provided the use of the hybrid artificial board as described in the first aspect in the field of house construction and decoration.

[0129] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0130] Example 1

[0131] 1) A wood veneer structural unit is prepared according to a conventional veneer production method, wherein the wood veneer thickness of the core transverse wood veneer layer is 2.7 mm, and the wood veneer thickness of the surface transverse veneer layer is 1.4 mm.

[0132] 2) A flaky wood chip structural unit is prepared according to a conventional wood chip production method, wherein the wood chip length is 50 mm and the thickness is 0.2 mm.

[0133] 3) After the drying process, the above-mentioned wood veneer structural units and flaky wood shaving structural units enter the gluing process:

[0134] (1) Wood veneer structural unit: Glyceryl polyurethane resin is evenly sprayed on the surface of the veneer, wherein the core layer and the transverse veneer layer are double-sided glued, and the upper and lower surface transverse veneer layers are single-sided glued, and the glue coating amount is 150g / mm 2 ;

[0135] (2) Wood shavings structural unit: the measured isocyanate adhesive and wood shavings are fed into a glue mixer and mixed evenly;

[0136] 4) Lay the lower surface transverse wood veneer layer, the lower inner surface longitudinal shavings layer, the core layer transverse wood veneer layer, the upper inner surface longitudinal shavings layer, and the upper surface transverse wood veneer layer on the conveyor belt in sequence, and the texture of the longitudinal shavings layer forms an angle of 90° with the texture of the wood veneer to obtain a continuous slab.

[0137] 5) The paved slab is continuously pre-pressed using a pair of pressure rollers with a pre-pressing pressure of 4.0 MPa.

[0138] 6) Steam preheating: Before the slab enters the press, steam preheating is used to preheat the temperature of the longitudinal particle layer to 85°C within 20 seconds.

[0139] 7) Hot pressing: using a continuous flat press with a hot pressing factor of 5s / mm.

[0140] After the above steps, a five-layer structured hybrid artificial board with a total thickness of 18 mm is obtained, wherein the thickness of the transverse wood veneer layer accounts for 30% of the total thickness of the hybrid artificial board.

[0141] Example 2

[0142] 1) A wood veneer structural unit is prepared according to a conventional veneer production method, wherein the wood veneer thickness of the core transverse wood veneer layer is 2.5 mm, and the wood veneer thickness of the inner surface transverse wood veneer layer is 1.0 mm.

[0143] 2) A flaky wood chip structural unit was prepared according to a conventional wood chip production method, wherein the wood chips had a length of 200 mm and a thickness of 1.2 mm.

[0144] 3) Preparing granular fine wood shavings structural units according to conventional wood shavings production methods.

[0145] 4) After the above-mentioned wood veneer structural units, flaky wood shavings structural units and granular wood shavings have been dried, they enter the gluing process:

[0146] (1) Wood veneer structural unit: Spray urea-formaldehyde resin adhesive evenly on both surfaces of the wood veneer, with a coating amount of 300g / mm 2 ;

[0147] (2) Wood shavings structural unit: the measured urea-formaldehyde resin adhesive and wood shavings are fed into a glue mixer and mixed evenly;

[0148] (3) Granular fine wood shavings structure single structural unit: The measured urea-formaldehyde resin adhesive and wood shavings are sent into a glue mixer and mixed evenly.

[0149] 5) Lay the lower surface granular shavings, the lower inner surface transverse veneer layer, the lower shavings layer, the core layer transverse veneer layer, the upper shavings layer, the upper inner surface transverse veneer layer, and the upper surface granular shavings on the conveyor belt in sequence, and the texture of the shavings layer forms an angle of 125° with the texture of the wood veneer to obtain a continuous slab.

[0150] 6) The paved slab is continuously pre-pressed using a pair of pressure rollers with a pre-pressing pressure of 5.0 MPa.

[0151] 7) Steam preheating: Before the slab enters the press, steam preheating is used to preheat the temperature of the longitudinal particle layer to 65°C within 20 seconds.

[0152] 8) Hot pressing: using a continuous flat press with a hot pressing factor of 8s / mm.

[0153] After the above steps, a seven-layer structured hybrid artificial board with a total thickness of 18 mm is obtained, wherein the thickness of the transverse wood veneer layer accounts for 25% of the total thickness of the hybrid artificial board.

[0154] Example 3

[0155] 1) A wood veneer structural unit is prepared according to a conventional veneer production method, wherein the thickness of the wood veneer in the transverse wood veneer layer is 1.8 mm.

[0156] 2) A flaky wood chip structural unit is prepared according to a conventional wood chip production method, wherein the wood chip length is 70 mm and the thickness is 0.5 mm.

[0157] 3) Prepare gypsum powder particle structural units according to conventional gypsum production methods.

[0158] 4) After the drying process, the above-mentioned wood veneer structural units and flaky wood shaving structural units enter the gluing process:

[0159] (1) Wood veneer structural unit: spray glycerol-based polyurethane resin evenly on both surfaces of the wood veneer, with a coating amount of 150g / mm 2 ;;

[0160] (2) Wood shavings structural unit: the measured isocyanate adhesive and wood shavings are fed into a glue mixer and mixed evenly;

[0161] (3) Inorganic powdery particle structural unit: The measured glyceryl polyurethane resin and gypsum powdery particle structural unit are mixed uniformly.

[0162] 5) Laying the lower surface powder structure unit, the lower flake layer, the core layer transverse veneer layer, the upper flake layer, and the upper surface powder structure unit on the conveyor belt in sequence, the flake layer texture and the wood veneer texture are at an angle of 80° to obtain a continuous slab.

[0163] 6) The paved slab is continuously pre-pressed using a pair of pressure rollers with a pre-pressing pressure of 6.0 MPa.

[0164] 7) Steam preheating: Before the slab enters the press, steam preheating is used to preheat the temperature of the longitudinal particle layer to 70°C within 20 seconds.

[0165] 8) Hot pressing: using a continuous flat press with a hot pressing factor of 7s / mm.

[0166] After the above steps, a five-layer hybrid artificial board with a total thickness of 18 mm is obtained, wherein the thickness of the transverse wood veneer layer accounts for 10% of the total thickness of the hybrid artificial board.

[0167] Example 4

[0168] 1) A wooden veneer structural unit is prepared according to a conventional wooden veneer production method, wherein the wooden veneer thickness of the transverse wooden veneer layer is 2.3 mm.

[0169] 2) A flaky wood chip structural unit is prepared according to a conventional wood chip production method, wherein the wood chip length is 150 mm and the thickness is 0.7 mm.

[0170] 3) Preparing granular fine wood shavings structural units according to conventional wood shavings production methods.

[0171] 4) After the drying process, the above-mentioned wood veneer structural units and flaky wood shaving structural units enter the gluing process:

[0172] (1) Wood veneer structural unit: Spray the biomass resin adhesive evenly on both surfaces of the veneer, with a coating amount of 150g / mm 2 ;

[0173] (2) Wood shavings structural unit: the measured isocyanate adhesive and wood shavings are fed into a glue mixer and mixed evenly;

[0174] (3) Granular fine wood shavings structure single structural unit: The measured phenolic resin adhesive and wood shavings are sent into a glue mixer and mixed evenly.

[0175] 5) Lay the lower surface granular wood shavings, the lower longitudinal wood shavings layer, the core layer transverse veneer layer, the upper longitudinal wood shavings layer, and the upper surface granular wood shavings on the conveyor belt in sequence, and the texture of the longitudinal wood shavings layer and the texture of the wood veneer are at an angle of 100 degrees to obtain a continuous slab.

[0176] 6) The paved slab is continuously pre-pressed using a pair of pressure rollers with a pre-pressing pressure of 3.0 MPa.

[0177] 7) Steam preheating: Before the slab enters the press, steam preheating is used to preheat the temperature of the longitudinal particle layer slab to 80°C within 20 seconds.

[0178] 8) Hot pressing: using a continuous flat press with a hot pressing factor of 5s / mm.

[0179] After the above steps, a five-layer hybrid artificial board with a total thickness of 18 mm is obtained, wherein the thickness of the transverse wood veneer layer accounts for 13% of the total thickness of the hybrid artificial board.

[0180] Example 5

[0181] 1) A wooden veneer structural unit is prepared according to a conventional wooden veneer production method, wherein the wooden veneer thickness of the transverse wooden veneer layer is 4.5 mm.

[0182] 2) A flaky wood particle structure unit is prepared according to a conventional wood particle production method, wherein the wood particles have a length of 60 mm and a thickness of 0.5 mm.

[0183] 3) Preparing granular fine wood shavings structural units according to conventional wood shavings production methods.

[0184] 4) After the drying process, the above-mentioned wood veneer structural units and flaky wood shaving structural units enter the gluing process:

[0185] (1) Wood veneer structural unit: Apply biomass resin adhesive evenly on both surfaces of the wood veneer, with a coating amount of 260g / mm 2 ;

[0186] (2) Wood shavings structural unit: the measured urea-formaldehyde resin adhesive and wood shavings are fed into a glue mixer and mixed evenly;

[0187] (3) Granular fine wood shavings structure single structural unit: The measured urea-formaldehyde resin adhesive and wood shavings are sent into a glue mixer and mixed evenly.

[0188] 5) Lay the lower surface shavings layer, the core layer transverse veneer layer, and the upper surface shavings layer on the conveyor belt in sequence, with the shavings layer texture and the wood veneer texture forming an angle of 110° to obtain a continuous slab.

[0189] 6) The paved slab is continuously pre-pressed using a pair of pressure rollers with a pre-pressing pressure of 5.0 MPa.

[0190] 7) Steam preheating: Before the slab enters the press, steam preheating is used to preheat the temperature of the longitudinal particle layer to 75°C within 20 seconds.

[0191] 8) Hot pressing: using a continuous flat press with a hot pressing factor of 8s / mm.

[0192] After the above steps, a three-layer hybrid artificial board with a total thickness of 18 mm is obtained, wherein the thickness of the transverse wood veneer layer accounts for 17% of the total thickness of the hybrid artificial board.

[0193] Example 6

[0194] 1) A wooden veneer structural unit is prepared according to a conventional wooden veneer production method, wherein the wooden veneer thickness of the transverse wooden veneer layer is 2.3 mm.

[0195] 2) Prepare fiber structural units according to conventional medium density fiberboard production methods.

[0196] 3) After the drying process, the above-mentioned wood veneer structural unit enters the gluing process, and the glycerol-based polyurethane resin adhesive is evenly sprayed on the two surfaces of the wood veneer, with a glue coating amount of 150g / mm 2 ;

[0197] 4) The measured modified urea-formaldehyde resin is mixed with the separated wet fibers at the outlet of the hot mill and then enters the drying pipeline for drying to a specified moisture content.

[0198] 5) Lay the lower surface fiber, the core layer transverse veneer layer, and the upper surface fiber on the conveyor belt in sequence, with the fiber texture and the wood veneer texture forming an angle of 75° to obtain a continuous slab.

[0199] 6) The paved slab is continuously pre-pressed using a pair of pressure rollers with a pre-pressing pressure of 4.0 MPa.

[0200] 7) Steam preheating: Before the slab enters the press, steam preheating is used to preheat the slab temperature to 65°C within 20 seconds.

[0201] 8) Hot pressing: using a continuous flat press with a hot pressing factor of 7s / mm.

[0202] After the above steps, a three-layer hybrid artificial board with a total thickness of 18 mm is obtained, wherein the thickness of the transverse wood veneer layer accounts for 13% of the total thickness of the hybrid artificial board.

[0203] Example 7

[0204] 1) A wood veneer structural unit is prepared according to a conventional wood veneer production method, wherein the wood veneer thickness of the core transverse wood veneer layer is 3.0 mm, and the veneer thickness of the surface transverse wood veneer layer is 1.5 mm.

[0205] 2) A flaky wood chip structural unit is prepared according to a conventional wood chip production method, wherein the wood chip length is 50 mm and the thickness is 0.2 mm.

[0206] 3) After the drying process, the above-mentioned wood veneer structural units and flaky wood shaving structural units enter the gluing process:

[0207] (1) Wood veneer structural unit: spray isocyanate adhesive evenly on the surface of the wood veneer, with the core layer and the transverse wood veneer layer coated on both sides, and the upper and lower surfaces and the transverse wood veneer layer coated on one side, with the coating amount of 150g / mm 2 ;

[0208] (2) Wood shavings structural unit: the measured isocyanate adhesive and wood shavings are fed into a glue mixer and mixed evenly;

[0209] 4) Lay the lower surface transverse veneer layer, the lower inner surface longitudinal shaving layer, the core layer transverse veneer layer, the upper inner surface longitudinal shaving layer, and the upper surface transverse veneer layer on the conveyor belt in sequence, and the texture of the longitudinal shaving layer forms an angle of 90° with the texture of the wood veneer to obtain a continuous slab.

[0210] 5) The paved slab is continuously pre-pressed using a pair of pressure rollers with a pre-pressing pressure of 3.0 MPa.

[0211] 6) Steam preheating: Before the slab enters the press, steam preheating is used to preheat the temperature of the longitudinal particle layer slab to 80°C within 16 seconds.

[0212] 7) Hot pressing: using a continuous flat press with a hot pressing factor of 4s / mm.

[0213] After the above steps, a five-layer hybrid artificial board with a total thickness of 15 mm is obtained, wherein the thickness of the transverse wood veneer layer accounts for 40% of the total thickness of the hybrid artificial board.

[0214] Example 8

[0215] 1) A wood veneer structural unit is prepared according to a conventional wood veneer production method, wherein the wood veneer thickness of the core transverse wood veneer layer is 3.0 mm, and the wood veneer thickness of the surface transverse wood veneer layer is 1.5 mm.

[0216] 2) A flaky wood chip structural unit is prepared according to a conventional wood chip production method, wherein the wood chip length is 50 mm and the thickness is 0.3 mm.

[0217] 3) After the drying process, the above-mentioned wood veneer structural units and flaky wood shaving structural units enter the gluing process:

[0218] (1) Wood veneer structural unit: The adhesive is sprayed evenly on the surface of the wood veneer, and the core layer and the transverse wood veneer layer are coated with isocyanate adhesive on both sides, with the coating amount of 150g / mm 2 The upper and lower surfaces of the horizontal wood veneer layer are coated with phenolic resin on one side, with a coating amount of 250g / mm 2 ;

[0219] (2) Wood shavings structural unit: the measured isocyanate adhesive and wood shavings are fed into a glue mixer and mixed evenly;

[0220] 4) Lay the lower surface transverse veneer layer, the lower inner surface longitudinal shaving layer, the core layer transverse veneer layer, the upper inner surface longitudinal shaving layer, and the upper surface transverse veneer layer on the conveyor belt in sequence, and the texture of the longitudinal shaving layer forms an angle of 95° with the texture of the wood veneer to obtain a continuous slab.

[0221] 5) The paved slab is continuously pre-pressed using a pair of pressure rollers with a pre-pressing pressure of 6.0 MPa.

[0222] 6) Steam preheating: Before the slab enters the press, steam preheating is used to preheat the temperature of the longitudinal particle layer slab to 85°C within 12 seconds.

[0223] 7) Hot pressing: using a continuous flat press with a hot pressing factor of 3.7s / mm.

[0224] After the above steps, a five-layer hybrid artificial board with a total thickness of 12 mm is obtained, wherein the thickness of the transverse wood veneer layer accounts for 50% of the total thickness of the hybrid artificial board.

[0225] Example 9

[0226] A hybrid artificial board was prepared according to the method of Example 1, wherein the components and proportions of the glycerol-based polyurethane resin adhesive used were as follows:

[0227] Highly branched glycerol polyester polyol prepolymer

[0228] Polyurethane prepolymer with NCO terminal group;

[0229] And the OH / NCO molar ratio of the two components is 0.8;

[0230] The preparation process of the highly branched glycerol polyester polyol prepolymer comprises the following steps:

[0231] (1) 100 parts by weight of glycerol were added into a reaction kettle while stirring, and the temperature was raised to 70° C. within 20 minutes.

[0232] (2) Gradually add a certain amount of maleic anhydride to glycerol, control the glycerol / maleic anhydride molar ratio to be 0.9-1.1, add for 1 hour, control the reaction temperature to be 90°C, and stir the reaction for 2 hours.

[0233] (3) 100 parts by weight of maleic anhydride were added into the reaction kettle while stirring, and the temperature of the reaction kettle was controlled to be 70°C.

[0234] (4) Gradually add a certain amount of glycerol dropwise into the reaction kettle, control the maleic anhydride / glycerol molar ratio to be 3.0-3.1, add for 1 hour, control the reaction temperature to be 90°C, and stir the reaction for 2 hours.

[0235] (5) raising the temperature to 140° C. and keeping the temperature for reaction for 3 hours, and obtaining a highly branched glycerol polyester polyol prepolymer after cooling, which can be diluted with water to a solid content of 60-80% according to process requirements.

[0236] The preparation process of the terminal NCO polyurethane prepolymer includes the following steps:

[0237] (1) 100 parts by weight of an isocyanate compound is added to a reaction kettle under stirring, and the temperature is raised to 50° C. within 20 minutes; the isocyanate compound is TDI;

[0238] (2) 10 parts of trimethylolpropane were added dropwise to the reaction kettle for 2 hours. The reaction temperature was controlled at 70°C and the reaction was stirred for 1 hour.

[0239] (3) After the reaction is completed, the product is cooled to room temperature to obtain the terminal NCO polyurethane prepolymer with an NCO content of 9-11%.

[0240] Preparation method of glycerol-based polyurethane resin adhesive:

[0241] The preparation method of the glycerol-based polyurethane resin adhesive comprises the following steps: uniformly mixing a highly branched glycerol polyester polyol prepolymer and a polyurethane prepolymer with an NCO terminal group at room temperature to obtain the glycerol-based polyurethane resin adhesive.

[0242] Example 10

[0243] A hybrid artificial board was prepared according to the method of Example 1, wherein the components and proportions of the glycerol-based polyurethane resin adhesive used were as follows:

[0244] Highly branched glycerol polyester polyol prepolymer

[0245] Polyurethane prepolymer with NCO terminal group;

[0246] And the OH / NCO molar ratio of the two components is 1.2;

[0247] The preparation process of the highly branched glycerol polyester polyol prepolymer comprises the following steps:

[0248] (1) 100 parts by weight of glycerol was added into a reaction kettle while stirring, and the temperature was raised to 60° C. within 20 minutes.

[0249] (2) Gradually add a certain amount of maleic anhydride to glycerol, control the glycerol / maleic anhydride molar ratio to be 0.9-1.1, add for 1 hour, control the reaction temperature to be 100° C., and stir the reaction for 2 hours.

[0250] (3) 100 parts by weight of maleic anhydride were added into the reaction kettle while stirring, and the temperature of the reaction kettle was controlled to be 60°C.

[0251] (4) Gradually add a certain amount of glycerol to the reaction kettle, control the maleic anhydride / glycerol molar ratio to 3.0-3.1, add for 1 hour, control the reaction temperature to 80°C, and stir the reaction for 2 hours.

[0252] (5) raising the temperature to 145° C. and keeping the temperature for reaction for 3 hours, and obtaining a highly branched glycerol polyester polyol prepolymer after cooling, which can be diluted with water to a solid content of 60-80% according to process requirements.

[0253] The preparation process of the terminal NCO polyurethane prepolymer includes the following steps:

[0254] (1) 100 parts by weight of an isocyanate compound is added to a reaction kettle under stirring, and the temperature is raised to 40° C. within 20 minutes; the isocyanate compound is MDI;

[0255] (2) 10 parts of highly branched glycerol polyester polyol prepolymer were added dropwise to the reaction kettle for 2 hours. The reaction temperature was controlled at 65° C. and the reaction was stirred for 1 hour.

[0256] (3) After the reaction is completed, the product is cooled to room temperature to obtain the terminal NCO polyurethane prepolymer with an NCO content of 9-11%.

[0257] Preparation method of glycerol-based polyurethane resin adhesive:

[0258] The preparation method of the glycerol-based polyurethane resin adhesive comprises the following steps: uniformly mixing a highly branched glycerol polyester polyol prepolymer and a polyurethane prepolymer with an NCO terminal group at room temperature to obtain the glycerol-based polyurethane resin adhesive.

[0259] Embodiment 11

[0260] A hybrid artificial board was prepared according to the method of Example 1, wherein the components and proportions of the glycerol-based polyurethane resin adhesive used were as follows:

[0261] Highly branched glycerol polyester polyol prepolymer

[0262] Polyurethane prepolymer with NCO terminal group;

[0263] and the OH / NCO molar ratio of the two components is 1.0;

[0264] The preparation process of the highly branched glycerol polyester polyol prepolymer comprises the following steps:

[0265] (1) 100 parts by weight of glycerol were added into a reaction kettle while stirring, and the temperature was raised to 80° C. within 20 minutes.

[0266] (2) Gradually add a certain amount of maleic anhydride to glycerol, control the glycerol / maleic anhydride molar ratio to be 0.9-1.1, add for 1 hour, control the reaction temperature to be 100° C., and stir the reaction for 2 hours.

[0267] (3) 100 parts by weight of maleic anhydride were added into the reaction kettle while stirring, and the temperature of the reaction kettle was controlled to be 80°C.

[0268] (4) Gradually add a certain amount of glycerol dropwise into the reaction kettle, control the maleic anhydride / glycerol molar ratio to be 3.0-3.1, add for 1 hour, control the reaction temperature to be 100° C., and stir the reaction for 2 hours.

[0269] (5) raising the temperature to 143° C. and keeping the temperature for reaction for 3 hours, and obtaining a highly branched glycerol polyester polyol prepolymer after cooling, which can be diluted with water to a solid content of 60-80% according to process requirements.

[0270] The preparation process of the terminal NCO polyurethane prepolymer includes the following steps:

[0271] (1) adding 100 parts by weight of an isocyanate compound into a reaction kettle while stirring, and heating the reaction kettle to 60° C. for 20 minutes; the isocyanate compound is PAPI;

[0272] (2) 10 parts of highly branched glycerol polyester polyol prepolymer or trimethylolpropane were added dropwise to the reaction kettle for 2 hours. The reaction temperature was controlled at 69° C. and the reaction was stirred for 1 hour.

[0273] (3) After the reaction is completed, the product is cooled to room temperature to obtain the terminal NCO polyurethane prepolymer with an NCO content of 9-11%.

[0274] Preparation method of glycerol-based polyurethane resin adhesive:

[0275] The preparation method of the glycerol-based polyurethane resin adhesive comprises the following steps: uniformly mixing a highly branched glycerol polyester polyol prepolymer and a polyurethane prepolymer with an NCO terminal group at room temperature to obtain the glycerol-based polyurethane resin adhesive.

[0276] Example 12

[0277] A hybrid artificial board was prepared according to the method of Example 3, wherein cement powder replaced gypsum powder, and the components and proportions of the glycerol-based polyurethane resin adhesive used were as follows:

[0278] Highly branched glycerol polyester polyol prepolymer

[0279] Polyurethane prepolymer with NCO terminal group;

[0280] and the OH / NCO molar ratio of the two components is 1.0;

[0281] The preparation process of the highly branched glycerol polyester polyol prepolymer comprises the following steps:

[0282] (1) 100 parts by weight of glycerol was added into a reaction kettle while stirring, and the temperature was raised to 72° C. within 20 minutes.

[0283] (2) Gradually add a certain amount of maleic anhydride to glycerol, control the glycerol / maleic anhydride molar ratio to be 0.9-1.1, add for 1 hour, control the reaction temperature to be 88°C, and stir the reaction for 2 hours.

[0284] (3) 100 parts by weight of maleic anhydride were added into the reaction kettle while stirring, and the temperature of the reaction kettle was controlled to be 68°C.

[0285] (4) Gradually add a certain amount of glycerol to the reactor, control the maleic anhydride / glycerol molar ratio to be 3.0-3.1, add for 1 hour, control the reaction temperature to be 92°C, and stir the reaction for 2 hours.

[0286] (5) Raise the temperature to 144° C. and keep the temperature to react for 3 hours. After cooling, obtain a highly branched glycerol polyester polyol prepolymer, which can be diluted with water to a solid content of 68% according to process requirements.

[0287] The preparation process of the terminal NCO polyurethane prepolymer includes the following steps:

[0288] (1) 100 parts by weight of an isocyanate compound is added to a reaction kettle under stirring, and the temperature is raised to 48° C. within 20 minutes; the isocyanate compound is TDI;

[0289] (2) 10 parts of highly branched glycerol polyester polyol prepolymer or trimethylolpropane were added dropwise to the reaction kettle for 2 hours. The reaction temperature was controlled at 69° C. and the reaction was stirred for 1 hour.

[0290] (3) After the reaction is completed, the product is cooled to room temperature to obtain the terminal NCO polyurethane prepolymer with an NCO content of 9-11%.

[0291] Preparation method of glycerol-based polyurethane resin adhesive:

[0292] The preparation method of the glycerol-based polyurethane resin adhesive comprises the following steps: uniformly mixing a highly branched glycerol polyester polyol prepolymer and a polyurethane prepolymer with an NCO terminal group at room temperature to obtain the glycerol-based polyurethane resin adhesive.

[0293] Example 13

[0294] A hybrid artificial board was prepared according to the method of Example 3, wherein stone powder replaced gypsum powder, and the components and proportions of the glycerol-based polyurethane resin adhesive used were as follows:

[0295] Highly branched glycerol polyester polyol prepolymer

[0296] Polyurethane prepolymer with NCO terminal group;

[0297] and the OH / NCO molar ratio of the two components is 1.0;

[0298] The preparation process of the highly branched glycerol polyester polyol prepolymer comprises the following steps:

[0299] (1) 100 parts by weight of glycerol were added into a reaction kettle while stirring, and the temperature was raised to 75° C. within 20 minutes.

[0300] (2) Gradually add a certain amount of maleic anhydride to glycerol, control the glycerol / maleic anhydride molar ratio to be 0.9-1.1, add for 1 hour, control the reaction temperature to be 95°C, and stir the reaction for 2 hours.

[0301] (3) 100 parts by weight of maleic anhydride were added into the reaction kettle while stirring, and the temperature of the reaction kettle was controlled to be 75°C.

[0302] (4) Gradually add a certain amount of glycerol to the reactor, control the maleic anhydride / glycerol molar ratio to be 3.0-3.1, add for 1 hour, control the reaction temperature to be 95°C, and stir the reaction for 2 hours.

[0303] (5) The temperature is raised to 141° C. and kept at this temperature for 3 hours. After cooling, a highly branched glycerol polyester polyol prepolymer is obtained, which can be diluted with water to a solid content of 65% according to process requirements.

[0304] The preparation process of the terminal NCO polyurethane prepolymer includes the following steps:

[0305] (1) 100 parts by weight of an isocyanate compound is added to a reaction kettle under stirring, and the temperature is raised to 54° C. within 20 minutes; the isocyanate compound is TDI and MDI;

[0306] (2) 10 parts of highly branched glycerol polyester polyol prepolymer or trimethylolpropane were added dropwise to the reaction kettle for 2 hours. The reaction temperature was controlled at 66° C. and the reaction was stirred for 1 hour.

[0307] (3) After the reaction is completed, the product is cooled to room temperature to obtain the terminal NCO polyurethane prepolymer with an NCO content of 9-11%.

[0308] Preparation method of glycerol-based polyurethane resin adhesive:

[0309] The preparation method of the glycerol-based polyurethane resin adhesive comprises the following steps: uniformly mixing a highly branched glycerol polyester polyol prepolymer and a polyurethane prepolymer with an NCO terminal group at room temperature to obtain the glycerol-based polyurethane resin adhesive.

[0310] Embodiment 14

[0311] A hybrid artificial board was prepared according to the method of Example 3, wherein talcum powder replaced gypsum powder, and the components and proportions of the glycerol-based polyurethane resin adhesive used were as follows:

[0312] Highly branched glycerol polyester polyol prepolymer

[0313] Polyurethane prepolymer with NCO terminal group;

[0314] and the OH / NCO molar ratio of the two components is 1.0;

[0315] The preparation process of the highly branched glycerol polyester polyol prepolymer comprises the following steps:

[0316] (1) 100 parts by weight of glycerol were added into a reaction kettle while stirring, and the temperature was raised to 70° C. within 20 minutes.

[0317] (2) Gradually add a certain amount of maleic anhydride to glycerol, control the glycerol / maleic anhydride molar ratio to be 0.9-1.1, add for 1 hour, control the reaction temperature to be 88°C, and stir the reaction for 2 hours.

[0318] (3) 100 parts by weight of maleic anhydride were added into the reaction kettle while stirring, and the temperature of the reaction kettle was controlled to be 68°C.

[0319] (4) Gradually add a certain amount of glycerol to the reactor, control the maleic anhydride / glycerol molar ratio to 3.0-3.1, add for 1 hour, control the reaction temperature to 88°C, and stir the reaction for 2 hours.

[0320] (5) Raising the temperature to 143° C. and keeping the temperature for reaction for 3 hours, and obtaining a highly branched glycerol polyester polyol prepolymer after cooling. The prepolymer can be diluted with water to a solid content of 78% according to process requirements.

[0321] The preparation process of the terminal NCO polyurethane prepolymer includes the following steps:

[0322] (1) 100 parts by weight of an isocyanate compound is added to a reaction kettle under stirring, and the temperature is raised to 50° C. for 20 minutes; the isocyanate compound is TDI, PAPI and MDI;

[0323] (2) 10 parts of highly branched glycerol polyester polyol prepolymer or trimethylolpropane were added dropwise to the reaction kettle for 2 hours. The reaction temperature was controlled at 70° C. and the reaction was stirred for 1 hour.

[0324] (3) After the reaction is completed, the product is cooled to room temperature to obtain the terminal NCO polyurethane prepolymer with an NCO content of 9-11%.

[0325] Preparation method of glycerol-based polyurethane resin adhesive:

[0326] The preparation method of the glycerol-based polyurethane resin adhesive comprises the following steps: uniformly mixing a highly branched glycerol polyester polyol prepolymer and a polyurethane prepolymer with an NCO terminal group at room temperature to obtain the glycerol-based polyurethane resin adhesive.

[0327] Performance Testing

[0328] The performance of the hybrid artificial panels prepared in Examples 1-14 was tested according to the national standard GB / T 4897-2015 and its guiding method. Comparative Examples 1-10 respectively used commercially available ordinary urea-formaldehyde resin particleboard (Comparative Examples 1-3), oriented particleboard (Comparative Examples 4-6) (mainly with different thickness specifications), medium density fiberboard (Comparative Example 7) and particleboard mixed with core layer isocyanate and surface layer urea-formaldehyde resin (Comparative Examples 8-10). The specific test results are shown in Table 1.

[0329] It can be seen that the longitudinal static bending strength and transverse static bending strength of the hybrid artificial board prepared in the examples slightly fluctuate due to the different selection of the board and the different angles, but are obviously generally better than the comparative examples; the formaldehyde emission of Examples 2, 4, 5, 6, and 8 using formaldehyde series resins is also significantly lower than that of the comparative examples due to the reduction of adhesives, but the bonding strength in the particleboard is not reduced as a result, and is slightly higher than the artificial boards currently on the market. In addition, the water absorption thickness expansion rate index of all samples is significantly better than that of the comparative examples, especially Examples 9-14, not only the formaldehyde emission is not detected, but the 24-hour water absorption thickness expansion rate is also significantly better than other examples and comparative examples, indicating that the glycerol-based polyurethane resin adhesive is a better choice.

[0330] Table 1 Performance test results

[0331]

[0332]

[0333] In summary, the hybrid artificial board and its preparation method provided by the present invention are optimized and reorganized by multiple structural units, enriching the varieties of artificial board products in my country. Compared with ordinary particleboard and oriented strand board, the transverse static bending strength is significantly improved, and compared with plywood, the production efficiency is significantly improved, and finally the adaptability of artificial board products is improved to meet the mechanical and dimensional stability requirements of artificial boards in different application fields, which is helpful for artificial boards to expand the application market, especially in the construction field. The present invention integrates the production of veneer artificial boards with particleboard (including oriented strand board) and medium-density fiberboard production technology, which helps to solve the technical difficulties of veneer artificial boards that are difficult to continuously and automatically produce and have low production efficiency. The method of the present invention is integrated with the existing continuous flat pressing production technology, without changing the basic production equipment and basic production process flow of the existing continuous flat pressing production line, and the equipment can be appropriately increased, which is convenient for the transformation and upgrading of the existing production line. Since the present invention uses large-sized veneer structural units, it is beneficial to reduce the amount of adhesive used, which is beneficial to reducing manufacturing costs, and also reduces the formaldehyde emission of artificial boards, thereby helping to further improve the environmental protection level of artificial boards. The preheating technology in the present invention can speed up the heating rate of the core layer of the slab and accelerate the curing of the resin adhesive, which is helpful to further improve the production efficiency of the whole line. In addition, the method of the present invention is applicable to various adhesives and can meet both environmental protection requirements and mechanical performance requirements.

[0334] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A hybrid artificial board, characterized in that: The hybrid artificial board has an odd number of layers, with the wood veneer as the core layer of the symmetric central plane, and the layers on both sides of the symmetric central plane correspond to each other; The structural units of the layers on both sides of the central plane of symmetry are wood veneers, wood chips, particles or fibers, and the adjacent layers are selected from different types of structural units; In the hybrid artificial board, the texture of the wood veneer is arranged along the vertical length direction of the hybrid artificial board; the texture or fiber of other types of structural units forms an angle of 60-90° with the texture of the wood veneer; The wooden veneer is spliced ​​along the length direction of the hybrid artificial board, and other types of structural unit layers are continuous structures.

2. The hybrid wood-based panel according to claim 1, characterized in that: The number of layers of the wooden veneer is 1-5; The thickness of the wood veneer of the core layer is 1.0-4.5 mm, and is greater than or equal to the thickness of the wood veneer of other layers.

3. The hybrid wood-based panel according to claim 1, characterized in that: The length of the wood chips is 50-200 mm, the thickness of the wood chips is 0.2-1.2 mm, and the arrangement of the wood chips is random arrangement and / or directional arrangement; The wood shavings layer is formed by bonding wood shavings with an adhesive, wherein the adhesive is selected from: formaldehyde series resins, isocyanate resins, glyceryl polyurethane resins or biomass resins; The formaldehyde series resin is selected from: urea-formaldehyde resin, modified urea-formaldehyde resin or phenol-formaldehyde resin.

4. The hybrid artificial board according to claim 1, characterized in that: The particle layer or fiber layer of the hybrid artificial board is bonded by an adhesive; The adhesive is selected from: formaldehyde series resin, isocyanate resin, glycerol-based polyurethane resin or biomass resin; The formaldehyde series resin is selected from: urea-formaldehyde resin, modified urea-formaldehyde resin or phenol-formaldehyde resin.

5. The hybrid wood-based panel according to claim 3 or 4, characterized in that: The glyceryl polyurethane resin adhesive comprises the following components: Highly branched glycerol polyester polyol prepolymer Polyurethane prepolymer with NCO terminal group; and the OH / NCO molar ratio of the two components is 0.8-1.2; The preparation method of the glycerol-based polyurethane resin adhesive comprises the following steps: uniformly mixing a highly branched glycerol polyester polyol prepolymer and a polyurethane prepolymer with an NCO terminal group at room temperature to obtain the glycerol-based polyurethane resin adhesive.

6. The hybrid artificial board according to claim 5, characterized in that: The preparation method of highly branched glycerol polyester polyol prepolymer is as follows: (1) adding 100 parts by weight of glycerol into a reaction kettle and stirring; (2) gradually adding maleic anhydride dropwise to glycerol with stirring, and controlling the glycerol / maleic anhydride molar ratio to be 0.9-1.1; (3) adding 100 parts by weight of maleic anhydride into a reaction kettle and stirring; (4) gradually adding a certain amount of glycerol dropwise into the reaction kettle, controlling the maleic anhydride / glycerol molar ratio to be 3.0-3.1; (5) heating the mixture to 140-145° C. and maintaining the temperature for at least 3 hours, and cooling the mixture to obtain a highly branched glycerol polyester polyol prepolymer; The preparation method of the polyurethane prepolymer with NCO terminal group is as follows: (1) adding 100 parts by weight of an isocyanate compound into a reaction kettle and stirring; the isocyanate compound includes: TDI, PAPI or MDI; (2) adding 10-50 parts by weight of highly branched glycerol polyester polyol prepolymer or trimethylolpropane dropwise into a reaction kettle and stirring; (3) After the reaction is completed, the product is cooled to room temperature to obtain the polyurethane prepolymer with NCO terminal groups.

7. The hybrid wood-based panel according to claim 5, characterized in that: The preparation method of highly branched glycerol polyester polyol prepolymer is as follows: (1) Add 100 parts by weight of glycerol into a reaction kettle, stir and heat to 60-80° C.; (2) gradually adding maleic anhydride dropwise to glycerol, and continuing to raise the temperature to 80-100° C., controlling the glycerol / maleic anhydride molar ratio to be 0.9-1.1; (3) adding 100 parts by weight of maleic anhydride into a reaction kettle, stirring and cooling to 60-80° C.; (4) gradually adding a certain amount of glycerol dropwise into the reaction kettle, controlling the maleic anhydride / glycerol molar ratio to be 3.0-3.1, and maintaining the reaction temperature to be 80-100° C.; (5) heating the mixture to 140-145° C. and maintaining the temperature for at least 3 hours, and cooling the mixture to obtain a highly branched glycerol polyester polyol prepolymer; The preparation method of the polyurethane prepolymer with NCO terminal group is as follows: (1) adding 100 parts by weight of an isocyanate compound into a reaction kettle, stirring and heating to 40-60° C.; the isocyanate compound includes: TDI, PAPI or MDI; (2) adding 10-50 parts by weight of highly branched glycerol polyester polyol prepolymer or trimethylolpropane dropwise into a reaction kettle, heating to 65-70° C. and stirring for reaction; (3) After the reaction is completed, the product is cooled to room temperature to obtain the polyurethane prepolymer with NCO terminal groups.

8. The method for preparing a hybrid wood-based panel according to any one of claims 1 to 7, characterized in that: The following steps are involved: (1) Laying wooden veneers continuously and splicing them into a continuous state, and spraying and / or pouring adhesive on the surface of the wooden veneers; (2) using the wood chips, particles or fibers to obtain a continuous particleboard, particleboard or fiberboard according to a continuous production process of particleboard, particleboard or fiberboard; (3) Continuously laying wood veneer, particle board, particle board and / or fiber board on both sides of the core layer by continuous laying; (4) The paved slab is continuously pre-pressed, preheated and hot-pressed to obtain a hybrid artificial board.

9. The preparation method according to claim 8, characterized in that: In step (1), the amount of glue applied on one side of the wood veneer is 150-300g / mm 2 .

10. The preparation method according to claim 8, characterized in that: In step (2), the method for preparing the particle board blank comprises: mixing the adhesive and the particles evenly, and then continuously paving them into the particle board blank.

11. The preparation method according to claim 8, characterized in that: The preparation method of the particle slab includes: mixing the adhesive and particles evenly, and then continuously paving the particle slab.

12. The preparation method according to claim 8, characterized in that: The preparation method of the fiber mat comprises: mixing the adhesive with the separated wet fibers at the outlet of the hot mill, drying to a specified moisture content, and then continuously paving the fiber mat.

13. The preparation method according to claim 8, characterized in that: In step (4), the continuous pre-pressing pressure is 3.0-6.0 MPa; and / or The preheating step specifically includes: preheating the wood chip layer slab to 65-85° C. within 20-60 seconds; and / or The hot pressing is performed using a continuous flat press; and / or The heat pressing factor of the heat pressing is 5-15s / mm.

14. Use of the hybrid artificial board according to claims 1 to 7 in the field of house construction and decoration.

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