Formaldehyde-free shaving board as well as preparation method and application thereof

Abstract

The invention provides a formaldehyde-free shaving board and a preparation method and application thereof. The formaldehyde-free shaving board comprises an upper surface layer, a core layer and a lower surface layer. Wherein the raw materials of the upper surface layer and the lower surface layer comprise wood shaving fines, an adhesive and water; the raw materials of the core layer comprise a wood shaving coarse material, an adhesive, a curing agent, a softening agent and water; wherein the adhesive comprises isocyanate. The curing agent can increase the curing speed of the adhesive isocyanate, and the softening agent can reduce the hardness of the shaving board, improve the elasticity and reduce the pre-curing of the adhesive before hot pressing, so that the problem that the difficulty of the post-treatment section of the isocyanate formaldehyde-free shaving board is higher than that of a urea-formaldehyde resin shaving board is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of particleboard, and relates to a formaldehyde-free particleboard, a preparation method thereof, and an application thereof. Background Art

[0002] China is a country rich in forest resources, but with a small per capita possession. With the development of the national economy, the demand for wood has gradually increased, and a large amount of raw logs are imported. Particleboard uses fast-growing wood or small-diameter wood as raw materials. Therefore, the development of particleboard can not only alleviate the demand for wood resources, but also protect the local ecological environment.

[0003] The traditional adhesives in the wood-based panel industry are "three aldehyde adhesives", namely: urea-formaldehyde resin adhesive, phenolic resin adhesive, and melamine-formaldehyde resin adhesive. After these three adhesives are used to produce wood-based panels, the panels will contain free formaldehyde, which will gradually be released into the environment, pollute the indoor air, and damage people's physical health. Currently, for wood-based panels using "three aldehyde adhesives", the main methods to reduce the formaldehyde emission of the panels are to optimize the adhesive formula (such as changing the ratio of urea to formaldehyde), add formaldehyde scavengers, etc. However, these methods still cannot achieve formaldehyde-free addition.

[0004] Isocyanate has been widely used in other industries. It has high bonding strength, strong water resistance, and does not contain formaldehyde. Good physical and mechanical properties can be obtained under the condition that the sizing amount is much lower than that of "three aldehyde adhesives". Although isocyanate adhesives have the above advantages, there are still some problems to be solved in the production process of formaldehyde-free particleboard. For example, due to the high hardness and small elasticity of the polyurea formed by the reaction of isocyanate with water in wood particles, it is difficult to process during sawing and veneering.

[0005] CN114181659A discloses a formaldehyde-free adhesive, which mainly improves the problem of slow curing speed and fails to solve the problems of too high hardness and poor elasticity of the finished board. CN115141343A discloses a formaldehyde-free particleboard additive, whose main function is to maintain excellent bonding performance and mechanical properties while further improving the production efficiency of formaldehyde-free wood-based panels, and also does not improve the problems of too high hardness and poor elasticity of the finished board.

[0006] In summary, at present, the production of formaldehyde-free wood-based panels using isocyanate as an adhesive still has problems such as serious pre-curing of the glue after sizing, low production efficiency, too high hardness of the board blank after hot pressing, and affecting subsequent processing, which need to be solved urgently. Summary of the Invention

[0007] Aiming at the deficiencies of the prior art, one of the objectives of the present invention is to provide a formaldehyde-free particleboard. This formaldehyde-free particleboard not only achieves formaldehyde-free addition, but also, under the same process conditions, has physical and mechanical properties similar to those of an isocyanate-based formaldehyde-free particleboard without adding a softener. However, the post-treatment processing is more convenient. The decrease in the saw blade speed makes it not easy to stick the edge, thereby increasing the saw blade life and improving the appearance of the board. After laminating, the dimensional stability is good, and there will be no problem of cracking due to the large difference in the deformation ability between the substrate and the laminate.

[0008] To achieve this purpose, the present invention adopts the following technical solutions:

[0009] A formaldehyde-free particleboard, the formaldehyde-free particleboard includes an upper surface layer, a core layer, and a lower surface layer; wherein, the raw materials of the upper surface layer and the lower surface layer include fine wood particles, an adhesive, and water; the raw materials of the core layer include coarse wood particles, an adhesive, a curing agent, a softener, and water; wherein, the adhesive includes isocyanate.

[0010] The polyether in the softener reacts with isocyanate to form a substance that is a soft foam, and its hardness is less than that of the product polyurea of water and isocyanate. The polyetheramine in the softener not only reacts with isocyanate to produce a soft foam, but also has a reaction rate greater than that of polyether, which can further improve the production efficiency. The long-chain hydrocarbon in the softener has an amino group that can react with isocyanate at one end and a rotatable ether bond at the other end, which improves the flexibility of the product. And because it contains a benzene ring, it has steric hindrance and lower reactivity before entering the hot pressing process, which can reduce the generation of pre-curing.

[0011] In the present invention, the adhesive refers to the adhesives of the upper surface layer, the lower surface layer, and the core material. The morphological dimensions of the wood particles in the present invention can be, for example, long and narrow flakes of 0.8-12 mm * 0.8-1.2 mm * 0.1-0.6 mm. By air classification of the wood particles, fine surface wood particles and coarse core wood particles are obtained. The present invention does not specifically limit the specific dimensions of the fine wood particles and the coarse wood particles. The relatively fine material obtained after screening can be used as the fine wood particles, and the relatively coarse material can be used as the coarse wood particles.

[0012] In an embodiment of the present invention, the raw materials of the upper surface layer and the lower surface layer are counted by weight as follows:

[0013] Fine wood particles 100 parts;

[0014] Isocyanate 3-10 parts;

[0015] Water 10-25 parts.

[0016] In an embodiment of the present invention, the raw materials of the core layer are counted by weight as follows:

[0017]

[0018] In one embodiment of the present invention, the mass ratio of the upper surface layer, the core layer and the lower surface layer is 1:(2.5 - 4):1, preferably 1:(3 - 3.5):1.

[0019] In one embodiment of the present invention, the functionality of the isocyanate is 2.6 - 2.7.

[0020] In one embodiment of the present invention, the -NCO value of the isocyanate is 25 - 35 wt%.

[0021] In one embodiment of the present invention, the isocyanate comprises polyphenylmethane diisocyanate.

[0022] In one embodiment of the present invention, the curing agent comprises an amine curing agent, preferably an aliphatic amine catalyst, more preferably one or more of triethylamine, triethylenediamine, N,N - dimethylcyclohexylamine, N,N - dimethylhexadecylamine, diethylenetriamine, and further preferably N,N - dimethylcyclohexylamine.

[0023] In one embodiment of the present invention, the softener comprises three substances A1, A2, and A3; preferably, A1 is a long - chain low - functionality polyether, preferably the functionality of A1 is 2 - 3 and the average molecular weight is 3000 - 6000, more preferably the molecular weight of A1 is 5000 - 6000; preferably, A2 is a polyetheramine capped with a primary amine and / or a secondary amine, preferably the functionality of A2 is 2 - 3 and the average molecular weight is 230 - 4000, more preferably the molecular weight of A2 is 230 - 2000; preferably, A3 is an alkane with a benzylamino group at one end and a phenylalkoxy group at the other end, preferably the number of carbon atoms in the main chain of A3 is ≥4 and the number of carbon atoms in the branched - chain phenylalkoxy group is ≥3, more preferably A3 is 6 - benzylamino - 1-(4'-phenylbutoxy)hexane; preferably, the mass ratio of A1, A2, and A3 is 1:(0.1 - 0.5):(0.1 - 1).

[0024] Another object of the present invention is to provide a method for preparing a formaldehyde - free particleboard.

[0025] A method for preparing a formaldehyde - free particleboard, the method for preparing the above - mentioned particleboard, the method comprising the following steps:

[0026] S1: Drying the fine materials of the surface layer and the coarse materials of the core layer of the wood particles;

[0027] S2: Applying the binder to the fine wood particles, adding water, and respectively obtaining the preliminary materials for the upper surface layer and the lower surface layer;

[0028] S3: Applying the binder, the curing agent, and the softener to the coarse wood particles, adding water, and obtaining the preliminary material for the core layer;

[0029] S4: placing the prepared material of the lower surface layer, the prepared material of the core layer and the prepared material of the upper surface layer into a paving box in sequence, paving and forming, and hot pressing to obtain the formaldehyde-free particle board;

[0030] In one embodiment of the present invention, S1 is dried to a moisture content of ≤2 wt%.

[0031] In one embodiment of the present invention, the temperature of S3 hot pressing is 180-250°C, the pressure is 0.5-6MpaG, and the time is 80-140s.

[0032] Another object of the present invention is to provide a method for preparing formaldehyde-free particleboard.

[0033] A use for preparing formaldehyde-free particleboard, wherein the particleboard is the particleboard mentioned above, or is a particleboard prepared by the method mentioned above, and the particleboard is used for furniture board.

[0034] Compared with the prior art, the present invention has at least the following beneficial effects:

[0035] (1) In the present invention, the raw materials for preparing the core layer of the formaldehyde-free board include adhesive isocyanate, curing agent and softener. The curing agent can improve the production efficiency of the formaldehyde-free board, and the use of the softener can improve the elasticity of the board, reduce the hardness of the board, and improve the production efficiency of the formaldehyde-free board.

[0036] (2) The particleboard provided by the present invention is not only free of formaldehyde, but also has similar physical and mechanical properties to isocyanate formaldehyde-free particleboard without softener under the same process conditions, but is more convenient for post-processing, and the saw blade speed is reduced, making it less likely to be fuzzy, thereby increasing the life of the saw blade and improving the appearance of the board. The dimensional stability after veneer is good, and cracking will not occur due to the large difference in deformation ability between the substrate and the veneer. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0038] Table 3

[0039]

[0040]

[0041] Example 1

[0042] In this embodiment, a formaldehyde-free particleboard is provided, and the formaldehyde-free particleboard comprises an upper surface layer, a core layer and a lower surface layer, and the raw materials of the upper surface layer and the lower surface layer both comprise the following components in parts by weight:

[0043] 3000g of wood shavings;

[0044] Isocyanate 120g;

[0045] 600g water;

[0046] The raw materials of the core layer include the following components in parts by weight:

[0047]

[0048] Among them, the brand of isocyanate is CW20, the curing agent is N,N-dimethylcyclohexylamine, the brands of softener are DEP-5631D (molecular weight 3000), D-230 and N-benzyl-6-(4-phenylbutoxy)hexane-1-amine oxalate, the mass ratio is 1:0.1:0.1, and the mass ratio of the upper surface layer, the core layer and the lower surface layer is 1:3:1.

[0049] The preparation method comprises the following steps:

[0050] (1) Before the experiment, the wood shavings were placed in a 120°C oven and dried to a moisture content of 2 wt%

[0051] (1) Pour wood shavings into a glue mixer, apply isocyanate using a compressed air spray gun, and then add water to obtain upper and lower surface preparations respectively;

[0052] (2) pouring the wood shavings into a glue mixer, applying isocyanate, curing agent, and softener using a compressed air spray gun, and then adding water to obtain a core layer preparation material;

[0053] (3) The prepared materials of the lower surface layer, the prepared materials of the core layer and the prepared materials of the upper surface layer are placed in a paving box in sequence. After paving and forming, they are compacted to expel the air in the middle, and then placed in a hot press machine for hot pressing and curing at 230° C. to obtain the formaldehyde-free particleboard.

[0054] The specific hot pressing process is as follows: the hot pressing factor is 6s / mm, and the hot pressing is carried out according to the following pressure and time:

[0055] 4MPa(G) / 20s+3.5MPa(G) / 25s+3MPa(G) / 15s+2MPa(G) / 15s+1.5MPa(G) / 20s+0.5MPa(G) / 13s.

[0056] Example 2

[0057] In this embodiment, a formaldehyde-free particleboard is provided, and the formaldehyde-free particleboard comprises an upper surface layer, a core layer and a lower surface layer. The raw materials for preparing the upper surface layer and the lower surface layer include the following components in parts by weight:

[0058] 3000g of wood shavings;

[0059] Isocyanate 120g;

[0060] 600g water;

[0061] The raw materials for preparing the core layer include the following components in parts by weight:

[0062]

[0063]

[0064] Among them, the brand of isocyanate is CW20, the curing agent is N,N-dimethylcyclohexylamine, the brand of softener is DEP-5631D (molecular weight 3000), D-230 and N-benzyl-6-(4-phenylbutoxy)hexane-1-amine oxalate, the mass ratio is 1:0.1:0.1, and the mass ratio of the upper surface layer, the core layer and the lower surface layer is 1:3.5:1.

[0065] The preparation method is the same as that of Example 1. Before the preparation, the wood shavings are placed in an oven at 120° C. and dried to a moisture content of 0.5 wt %.

[0066] Example 3

[0067] In this embodiment, a formaldehyde-free particleboard is provided, and the formaldehyde-free particleboard comprises an upper surface layer, a core layer and a lower surface layer. The raw materials for preparing the upper surface layer and the lower surface layer include the following components in parts by weight:

[0068] 3000g of wood shavings;

[0069] Isocyanate 150g;

[0070] 800g water;

[0071] The raw materials for preparing the core layer include the following components in parts by weight:

[0072]

[0073]

[0074] Among them, the brand of isocyanate is CW20, the curing agent is N, N-dimethylcyclohexylamine, the brand of softener is DEP-5631D (molecular weight 3000), D-4000 and 6-benzylamino-1-(4'-phenylbutoxy)hexane, the mass ratio is 1:0.1:0.1, and the mass ratio of the upper surface layer, core layer and lower surface layer is 1:3:1.

[0075] The preparation method is the same as that of Example 1. Before the preparation experiment, the wood shavings were placed in an oven at 120° C. and dried to a moisture content of 1 wt %.

[0076] Example 4

[0077] In this embodiment, a formaldehyde-free particleboard is provided, and the formaldehyde-free particleboard comprises an upper surface layer, a core layer and a lower surface layer. The raw materials for preparing the upper surface layer and the lower surface layer include the following components in parts by weight:

[0078] 3000g of wood shavings;

[0079] Isocyanate 240g;

[0080] 300g water;

[0081] The raw materials for preparing the core layer include the following components in parts by weight:

[0082]

[0083] Among them, the brand of isocyanate is CW20, the curing agent is N, N-dimethylcyclohexylamine, the brand of softener is DEP-5631D (molecular weight 3000), D-2000 and 6-benzylamino-1-(4'-phenylbutoxy)hexane, the mass ratio is 1:0.2:0.5, and the mass ratio of the upper surface layer, core layer and lower surface layer is 1:3:1.

[0084] The preparation method is the same as Example 1.

[0085] Example 5

[0086] In this embodiment, a formaldehyde-free particleboard is provided, and the formaldehyde-free particleboard comprises an upper surface layer, a core layer and a lower surface layer. The raw materials for preparing the upper surface layer and the lower surface layer include the following components in parts by weight:

[0087] 3000g of wood shavings;

[0088] Isocyanate 120g;

[0089] 600g water;

[0090] The raw materials for preparing the core layer include the following components in parts by weight:

[0091]

[0092] Among them, the brand of isocyanate is CW20, the curing agent is N, N-dimethylcyclohexylamine, the brand of softener is 10LD76E (molecular weight 5000), D-230 and 6-benzylamino-1-(4'-phenylbutoxy)hexane, the mass ratio is 1:0.1:0.1, and the mass ratio of the upper surface layer, core layer and lower surface layer is 1:3:1.

[0093] The preparation method is the same as Example 1.

[0094] Example 6

[0095] In this embodiment, a formaldehyde-free particleboard is provided, and the formaldehyde-free particleboard comprises an upper surface layer, a core layer and a lower surface layer. The raw materials for preparing the upper surface layer and the lower surface layer include the following components in parts by weight:

[0096] 3000g of wood shavings;

[0097] Isocyanate 120g;

[0098] 600g water;

[0099] The raw materials for preparing the core layer include the following components in parts by weight:

[0100]

[0101] Among them, the brand of isocyanate is CW20, the curing agent is N, N-dimethylcyclohexylamine, the brand of softener is 10LD76E (molecular weight 5000), D-4000 and 6-benzylamino-1-(4'-phenylbutoxy)hexane, the mass ratio is 1:0.1:0.1, and the mass ratio of the upper surface layer, core layer and lower surface layer is 1:3:1.

[0102] The preparation method is the same as Example 1.

[0103] Example 7

[0104] In this embodiment, a formaldehyde-free particleboard is provided, and the formaldehyde-free particleboard comprises an upper surface layer, a core layer and a lower surface layer. The raw materials for preparing the upper surface layer and the lower surface layer include the following components in parts by weight:

[0105] 3000g of wood shavings;

[0106] Isocyanate 120g;

[0107] 600g water;

[0108] The raw materials for preparing the core layer include the following components in parts by weight:

[0109]

[0110] Among them, the brand of isocyanate is CW20, the curing agent is N, N-dimethylcyclohexylamine, the brand of softener is 10LD76E (molecular weight 5000), D-2000 and 6-benzylamino-1-(4'-phenylbutoxy)hexane, the mass ratio is 1:0.1:0.1, and the mass ratio of the upper surface layer, core layer and lower surface layer is 1:3:1.

[0111] The preparation method is the same as Example 1.

[0112] Example 8

[0113] In this embodiment, a formaldehyde-free particleboard is provided, and the formaldehyde-free particleboard comprises an upper surface layer, a core layer and a lower surface layer. The raw materials for preparing the upper surface layer and the lower surface layer include the following components in parts by weight:

[0114] 3000g of wood shavings;

[0115] Isocyanate 120g;

[0116] 600g water;

[0117] The raw materials for preparing the core layer include the following components in parts by weight:

[0118]

[0119]

[0120] Among them, the brand of isocyanate is CW20, the curing agent is N, N-dimethylcyclohexylamine, the brand of softener is 10LD83E (molecular weight 6000), D-230 and 6-benzylamino-1-(4'-phenylbutoxy)hexane, the mass ratio is 1:0.1:0.1, and the mass ratio of the upper surface layer, core layer and lower surface layer is 1:3:1.

[0121] The preparation method is the same as Example 1.

[0122] Example 9

[0123] In this embodiment, a formaldehyde-free particleboard is provided, and the formaldehyde-free particleboard comprises an upper surface layer, a core layer and a lower surface layer. The raw materials for preparing the upper surface layer and the lower surface layer include the following components in parts by weight:

[0124] 3000g of wood shavings;

[0125] Isocyanate 120g;

[0126] 600g water;

[0127] The raw materials for preparing the core layer include the following components in parts by weight:

[0128]

[0129] Among them, the brand of isocyanate is CW20, the curing agent is N, N-dimethylcyclohexylamine, the brand of softener is 10LD83E (molecular weight 6000), D-2000 and 6-benzylamino-1-(4'-phenylbutoxy)hexane, the mass ratio is 1:0.1:0.1, and the mass ratio of the upper surface layer, core layer and lower surface layer is 1:3:1.

[0130] The preparation method is the same as Example 1.

[0131] Comparative Example 1

[0132] The only difference between this comparative example and Example 1 is that the raw materials for preparing the core layer do not include a softener.

[0133] Provided is a formaldehyde-free particleboard, comprising an upper surface layer, a core layer and a lower surface layer, wherein the raw materials for preparing the upper surface layer and the lower surface layer both comprise the following components in parts by weight:

[0134] 3000g of wood shavings;

[0135] Isocyanate 120g;

[0136] 600g water;

[0137] The raw materials for preparing the core layer include the following components in parts by weight:

[0138]

[0139] Among them, the brand of isocyanate is CW20, the curing agent is N, N-dimethylcyclohexylamine, and the mass ratio of the upper surface layer, the core layer and the lower surface layer is 1:3:1.

[0140] The rest of the preparation method is the same as in Example 1.

[0141] Comparative Example 2

[0142] The only difference between this comparative example and Example 1 is that the softener in the raw material for preparing the core layer is replaced by propyl ether.

[0143] Provided is a formaldehyde-free particleboard, comprising an upper surface layer, a core layer and a lower surface layer, wherein the raw materials for preparing the upper surface layer and the lower surface layer both comprise the following components in parts by weight:

[0144] 3000g of wood shavings;

[0145] Isocyanate 120g;

[0146] 600g water;

[0147] The raw materials for preparing the core layer include the following components in parts by weight:

[0148]

[0149] Among them, the brand of isocyanate is CW20, the curing agent is N, N-dimethylcyclohexylamine, the softener is propyl ether, and the mass ratio of the upper surface layer, the core layer and the lower surface layer is 1:3:1.

[0150] The preparation method is the same as Example 1.

[0151] The particleboards provided in the embodiments and comparative examples were tested for performance, and the testing method was as follows:

[0152] (1) 2-hour water absorption thickness expansion rate: Tested in accordance with test method 4.4 Water absorption thickness expansion rate determination method 1 specified in GB / T 17657-2013;

[0153] (2) Flexural strength and elastic modulus: Tested in accordance with test method 4.7 Flexural strength and elastic modulus determination (three-point bending) specified in GB / T 17657-2013;

[0154] (3) Internal bonding strength: Tested in accordance with test method 4.11 Internal bonding (bonding) strength test specified in GB / T 17657-2013;

[0155] (4) Physical and mechanical property requirements: Tested in accordance with Part 3 of GB / T 4897.3-2003 Particleboard: Requirements for furniture and interior decoration boards used in a dry state: For boards with a nominal thickness of 13 to 20 mm, static bending strength ≥ 13 MPa, elastic modulus ≥ 1600 MPa, internal bonding strength ≥ 0.35 MPa, and 2-hour water absorption thickness expansion rate ≤ 8%.

[0156] The hot press used in the experiment was Wuxi Deep's universal experimental press, and the instrument used to test the performance was a high-speed rail universal tensile testing machine.

[0157] The thickness and performance test results of the particleboard provided in the embodiments and comparative examples are shown in Table 4.

[0158] Table 4

[0159]

[0160] It can be seen from Table 4 that the internal bonding strength (0.43-0.48 MPa), static bending strength (14.7-15.2 MPa), elastic modulus (1945-2031 MPa) and 2-hour water absorption thickness expansion rate (3.2-4.1) of the formaldehyde-free particleboard provided in Examples 1-9 of the present invention can all meet the national standard requirements.

[0161] With the increase in the dosage of the softener in the present invention, the requirement for the rotational speed of the saw blade gradually decreases, and the problem of edge smearing is also solved.

[0162] The present invention uses the above embodiments to illustrate the formaldehyde-free particleboard of the present invention and its preparation method and application. However, the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement to the present invention, the equivalent substitution of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc., all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. An aldehyde-free particleboard, characterized in that, The formaldehyde-free particleboard comprises an upper surface layer, a core layer and a lower surface layer; wherein, the raw materials of the upper surface layer and the lower surface layer include fine wood particles, an adhesive and water; the raw materials of the core layer include coarse wood particles, an adhesive, a curing agent, a softening agent and water; Wherein, the adhesive comprises isocyanate.

2. The aldehyde-free particleboard according to claim 1, characterized in that, The raw materials of the upper surface layer and the lower surface layer are as follows by weight: Fine wood particles 100 parts; Isocyanate 3-10 parts; Water 10-25 parts; And / or, the raw materials of the core layer are as follows by weight:

3. The aldehyde-free particleboard according to claim 1 or 2, characterized in that, The mass ratio of the upper surface layer, the core layer and the lower surface layer is 1:(2.5-4):1, preferably 1:(3-3.5):

1.

4. The aldehyde-free particleboard according to any one of claims 1-3, characterized in that, The functionality of the isocyanate is 2.6-2.7; And / or, the -NCO value of the isocyanate is 25-35wt%; And / or, the isocyanate comprises polydiphenylmethane diisocyanate.

5. The aldehyde-free particleboard according to any one of claims 1-4, characterized in that, The curing agent comprises an amine curing agent, preferably an aliphatic amine catalyst, more preferably one or more of triethylamine, triethylenediamine, N,N-dimethylcyclohexylamine, N,N-dimethylhexadecylamine, diethylenetriamine, and further preferably N,N-dimethylcyclohexylamine.

6. The aldehyde-free particleboard according to any one of claims 1-5, characterized in that, The softening agent comprises three substances A1, A2, and A3; Preferably, A1 is a long-chain low-functionality polyether, preferably the functionality of A1 is 2-3 and the average molecular weight is 3000-6000, more preferably the molecular weight of A1 is 5000-6000; Preferably, A2 is a polyetheramine capped with a primary amine and / or a secondary amine, preferably the functionality of A2 is 2-3 and the average molecular weight is 230-4000, more preferably the molecular weight of A2 is 230-2000; Preferably, A3 is an alkane with a benzylamino group at one end and a phenylalkoxy group at the other end, preferably the number of carbon atoms in the main chain of A3 is ≥4 and the number of carbon atoms in the branched phenylalkoxy group is ≥3, more preferably A3 is 6-benzylamino-1-(4'-phenylbutoxy)hexane; Preferably, the mass ratio of A1, A2, and A3 is 1:(0.1-0.5):(0.1-1).

7. A method for preparing an aldehyde-free particleboard, the method preparing the particleboard according to any one of claims 1-6, characterized in that, The method comprises the following steps: S1: Dry the fine wood particles of the surface layer and the coarse wood particles of the core layer; S2: Apply the adhesive to the fine wood particles and add water to obtain the preliminary materials for the upper surface layer and the lower surface layer respectively; S3: Apply the adhesive, the curing agent and the softening agent to the coarse wood particles and add water to obtain the preliminary material for the core layer; S4: Put the preliminary material for the lower surface layer, the preliminary material for the core layer and the preliminary material for the upper surface layer into a laying box in sequence, lay and form, and hot press to obtain the formaldehyde-free particleboard.

8. The method according to claim 7, characterized in that, S1 is dried to a moisture content ≤2wt%; And / or, the temperature of the hot press in S3 is 180-250°C, the pressure is 0.5-6MpaG, and the time is 80-140s.

9. A use for preparing an aldehyde-free particleboard, the particleboard being the particleboard according to any one of claims 1-6, or the particleboard prepared by the method according to claim 7 or 8, and the particleboard being used for furniture boards.

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