High-elasticity artificial board, preparation method and drying device

Abstract

The present application belongs to the technical field of artificial board manufacturing, and particularly relates to a high-elastic artificial board, a preparation method and a drying device. The preparation comprises the following steps: (1) introducing a cross-linking agent directly into a high-molecular polymer network containing hydroxyl groups to form dynamic bond cross-linking points, thereby obtaining one or more dynamic coordination cross-linked high-molecular additives; (2) blending artificial board raw materials with the one or more dynamic coordination cross-linked high-molecular additives obtained in step (1), and then drying after multiple additions and blending; and (3) gluing the pretreated artificial board raw materials obtained in step (2), and then obtaining a high-elastic artificial board through hot pressing. The high-elastic artificial board prepared by the present application has the property that, when subjected to a certain degree of external stimulation, the bond will break and connect, so that the board rapidly becomes a high-elastic hard solid. The use of the drying device can significantly improve drying uniformity and reduce drying time.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of artificial board manufacturing, and particularly relates to a high-elastic artificial board, a preparation method and a drying device. BACKGROUND

[0002] Wooden floor is a popular home and commercial space floor decoration material, and is an indispensable carrier in the new era of human life, contains the longing and pursuit of a better life, and creates a comfortable and warm space. After nearly 30 years of development, China's wooden floor industry has made significant progress in technological innovation and brand establishment, and has formed a relatively complete industrial system. In recent years, China's wooden floor production has reached a stage of historical peak, and has shown a slow downward trend. The benefits of most products in this field have declined, and the industry development situation is severe. Science is the first driving force for industry development. Only continuous innovation and new products in the direction of people's needs can break the current predicament of the wooden floor industry.

[0003] In recent years, the whole people movement and home fitness have become a trend, and people's enthusiasm for exercise has increased day by day. The comfort of the exercise area floor for people's walking has become an important factor. In order to meet the needs of people for high-quality exercise areas, high-elastic floor is urgently needed to be developed. This kind of floor makes the floor material quickly become a high-elastic hard solid when people are engaged in intense exercise or sports competition. SUMMARY

[0004] In view of the above shortcomings, the application provides a high-elastic artificial board, a preparation method and a drying device to obtain a high-elastic hard and high-quality artificial board.

[0005] In order to achieve the above purpose, the application adopts the following technical scheme:

[0006] A high-elastic artificial board preparation method,

[0007] comprising the following steps:

[0008] (1) introducing small molecules or inorganic electrolytes as cross-linking agents into a high-molecular polymer network containing hydroxyl groups to form dynamic bond cross-linking points, obtaining one or more dynamic coordination cross-linked high-molecular additives, the coordination-driven cross-linking network has a novel system with reversible and dynamic characteristics, and will produce bond rupture and connection when subjected to a certain degree of external stimulus;

[0009] (2) blending the artificial board raw materials with one or more dynamic coordination cross-linked high-molecular additives obtained in step (1), and after multiple additions and blending, drying to obtain the dynamic coordination cross-linked high-molecular additive pretreated artificial board raw materials;

[0010] (3) gluing the pretreated wood-based board raw material obtained in step (2) and then hot-pressing to obtain the high-elastic wood-based board.

[0011] Optionally, the small molecule or inorganic electrolyte crosslinking agent is boric acid and / or borax and / or small molecule organic boric acid and its derivatives; the introducing process in step (1) refers to providing a reaction condition of the small molecule or inorganic electrolyte crosslinking agent and the hydroxyl-containing high polymer to form the dynamic bond crosslinking point in the high polymer network.

[0012] Optionally, the hydroxyl-containing high polymer is a hydroxyl-modified polyurethane and / or a hydroxyl-terminated polysiloxane and / or a modified epoxy resin.

[0013] Optionally, the wood-based board raw material is wood fiber and / or wood shaving and / or thin wood sheet.

[0014] Optionally, the blending method in step (2) comprises stirring or soaking or spraying or ultrasonic oscillation. Optionally, the weight ratio of the dynamic coordination crosslinked high molecular additive to the wood-based board raw material in step (2) is 1-20:100.

[0015] Optionally, in step (3), the glue used in the gluing step is urea-formaldehyde resin and / or melamine-modified urea-formaldehyde resin and / or MDI glue and / or other general process glue for wood-based boards.

[0016] Optionally, in step (2), a drying device is used for drying and water removal, and the water content is controlled to be below 10%.

[0017] A high-elastic wood-based board is prepared by using the high-elastic wood-based board preparation method described above. A drying device is applied to the drying section in step (2) of the high-elastic wood-based board preparation method described above.

[0018] The device body is provided with a centrifugal drying turntable, and a plurality of drying air outlets are arranged on the centrifugal drying turntable; a drying gas chamber is arranged below the centrifugal drying turntable; the drying gas chamber is communicated with a drying air inlet pipe; a turntable cover and a feeding air extraction pipe are arranged above the centrifugal drying turntable, and the turntable cover is rotatably arranged on the feeding air extraction pipe; the lower part of the feeding air extraction pipe is liftably arranged, the upper part of the feeding air extraction pipe is communicated with an air extraction pipe, and the top of the feeding air extraction pipe is communicated with a feeding hopper.

[0019] Compared with the prior art, the high-elastic wood-based board preparation method has the following beneficial effects:

[0020] 1. The preparation method of the high-elastic artificial board of the present application establishes a coordination-driven crosslinking network, which is a novel system with reversible and dynamic characteristics, and can change the conventional wood floor into a high-elastic hard floor under external stimulation without additional energy, has a comfortable walking feeling and a sense of movement, and is suitable for decoration, floor and other fields in indoor, public places, gymnasiums and the like.

[0021] 2. The preparation method of the high-elastic artificial board of the present application adds a dynamic coordination crosslinking polymer additive under the condition of keeping the original process of the wood floor, and the additive is suitable for the existing conventional wood floor manufacturing process, without the need for additional modification and change of equipment, reduces the cost of new product development, and is beneficial to the wide promotion of new products.

[0022] 3. The preparation method of the high-elastic artificial board of the present application, the dynamic coordination crosslinking polymer additive is suitable for most artificial board adhesives and additives, and different types of wood floor products can be customized according to requirements.

[0023] 4. The preparation method of the high-elastic artificial board of the present application, the dynamic coordination crosslinking polymer additive adds a crosslinking network between the adhesives, artificial board raw materials, additives and the like, and effectively improves the adhesion performance of the adhesives and the physical properties of the artificial board. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description.

[0025] Figure 1 is a structural schematic diagram of the drying device of the present application;

[0026] Figures 2a-2b is a detection report of the comparative example 2 of the present application;

[0027] Figures 3a-3b is a detection report of the embodiment 1 of the present application. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0029] In the description of the present application, it should be noted that the terms "inner", "front", "rear", "left", "right" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0030] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "arrangement", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0031] A method for preparing a high-elastic artificial board, comprising the following steps:

[0032] (1) introducing small molecules or inorganic electrolytes as cross-linking agents directly into a high-molecular polymer network containing hydroxyl groups to form dynamic bond cross-linking points, to obtain one or more dynamic coordination cross-linked high-molecular additives, the coordination-driven cross-linking network has a novel system with reversible and dynamic characteristics, and will produce bond breaking and connection when subjected to a certain degree of external stimulus;

[0033] (2) blending the artificial board raw materials with one or more dynamic coordination cross-linked high-molecular additives obtained in step (1), and after multiple additions and blending, drying to obtain the dynamic coordination cross-linked high-molecular additive pretreated artificial board raw materials;

[0034] (3) sizing the pretreated artificial board raw materials obtained in step (2), and then hot pressing to obtain a high-elastic artificial board.

[0035] Optionally, the small molecule or inorganic electrolyte cross-linking agent is boric acid and / or borax and / or small molecule organic boric acid and its derivatives; the introduction process in step (1) refers to providing reaction conditions of the small molecule or inorganic electrolyte cross-linking agent and the high-molecular polymer containing hydroxyl groups to form the dynamic bond cross-linking points in the high-molecular polymer network.

[0036] Optionally, the high-molecular polymer containing hydroxyl groups is a hydroxyl-modified polyurethane and / or a hydroxyl-terminated polysiloxane and / or a modified epoxy resin.

[0037] Optionally, the artificial board raw materials are wood fibers and / or wood shavings and / or thin wood sheets.

[0038] Optionally, the blending method in step (2) comprises stirring or soaking or spraying or ultrasonic oscillation. Optionally, the weight ratio of the dynamic coordination cross-linked polymer additive to the wood-based panel raw material in step (2) is 1-20:100.

[0039] Optionally, in step (3), the glue used in the gluing step is urea-formaldehyde resin and / or melamine modified urea-formaldehyde resin and / or MDI glue and / or other common process glue for wood-based panels.

[0040] Optionally, in step (2), a drying device is used for drying and water removal, and the moisture content is controlled to be below 10%.

[0041] In order to better understand the present application, the following specific examples and comparative examples are listed:

[0042] The high-elastic wood-based panel preparation method embodiment 1 of the present application comprises the following steps:

[0043] (1) 20 parts of boric acid is dissolved in 20 parts of water solution, and magnetic stirring is performed for 60 min to uniformly mix to obtain a boric acid aqueous solution;

[0044] (2) 100 parts of hydroxyl-terminated polydimethylsiloxane is dispersed in 100 parts of glycerol, and magnetic stirring is performed for 60 min to uniformly mix to obtain a dynamic coordination cross-linked polymer additive;

[0045] (3) The eucalyptus wood fibers are blended with the dynamic coordination cross-linked high molecular additive obtained in step (1) and boric acid aqueous solution. The blending operation method is as follows: the two solutions are blended at room temperature, and an emulsion is formed under intense stirring. After standing, the emulsion is layered, so the additive and boric acid water are uniformly mixed by spraying while stirring. After multiple additions and blending, drying is performed. In this scheme, the drying step is critical: it is mainly to prevent the oxidation and decomposition of the above reagents, and to ensure uniform drying inside and outside the wood fibers (the quality of this drying step will affect the proportion of hydroxyl-terminated polydimethylsiloxane combined to the fibers, that is, the building effect of the cross-linked network, which directly affects the high elasticity effect of the board. Therefore, the purpose of drying is low-temperature drying and minimizing the drying time, and then the next step of gluing and board making is performed. In this embodiment, a special drying device of the application is preferred, which realizes low-temperature rapid drying by controlling the drying temperature below 80°C (optionally 55°C, 60°C, 65°C and 70°C, etc.), and then realizes low-temperature rapid drying by using a combination of negative pressure air extraction, high-pressure air injection and centrifugation. Under the conditions of preventing oxidation of the reagents at low temperature and improving the drying speed, the moisture content inside and outside the fibers can also be ensured to be uniform, avoiding the drawbacks of traditional drying machines, which are high-temperature drying and excessive drying of the outer layer of the fibers while the inner layer has a high moisture content, which affects the building effect of the cross-linked network. The ratio of eucalyptus wood fibers, dynamic coordination cross-linked high molecular additive and boric acid aqueous solution is 600:40:8, and the moisture content of the eucalyptus wood fibers after drying is 10%. Under the action of hydrogen bonding, the hydroxyl-terminated polydimethylsiloxane is combined to the fibers, and at the same time, based on the cross-linking effect of the boric acid particles, the dihydroxy polydimethylsiloxane is dynamically cross-linked with the fibers, to obtain eucalyptus wood fibers pretreated by dynamic coordination cross-linked high molecular additive;

[0046] (4) The pretreated eucalyptus wood fibers obtained in step (2) are applied with MDI glue, and the ratio of MDI glue to pretreated eucalyptus wood fibers is 1:20, and then high-elasticity artificial board is obtained by hot pressing. The artificial board prepared in Example 1 is detected for related indexes.

[0047] Comparative Example 1

[0048] Comparative Example 1 uses a conventional fiberboard preparation method, which includes the following steps:

[0049] (1) The eucalyptus wood fibers are dried, and the moisture content of the eucalyptus wood fibers after drying is 10%.

[0050] (2) The pretreated eucalyptus wood fibers obtained in step (1) are applied with MDI glue, and the ratio of MDI glue to pretreated eucalyptus wood fibers is 1:20, and then high-elasticity artificial board is obtained by hot pressing. The artificial board prepared in Comparative Example 2 is detected for related indexes.

[0051] Comparative Example 2

[0052] The difference between the present comparative example 2 and example 1 is that the drying is performed at the same temperature using a conventional drying machine until the average eucalyptus fiber moisture content is 10% (since the conventional drying machine is a static drying, it not only needs a longer drying time, but also the moisture content inside and outside the fiber is different, the moisture content of the outer layer is much lower than that of the inner layer, so the average moisture content is taken), and the relevant indicators of the artificial board prepared in the present comparative example 2 are detected.

[0053] The elastic modulus and impact toughness of the artificial boards of example 1, comparative example 1 and comparative example 2 are tested, and the mechanical property test refers to the standard of GB / T 17657—2022 “Test methods of physical and chemical properties of wood-based panels and veneered wood-based panels”, and the results are shown in table 1. The elastic modulus and impact toughness of the experimental board of example 1 are better than those of the artificial boards of comparative examples 1 and 2, which indicates that the experimental board has good toughness and better deformation ability under external force impact, and the internal bonding strength is increased, which indicates that the addition of the dynamic coordination cross-linked polymer additive has a reinforcing effect on the adhesive of the conventional fiber board.

[0054] Table 1 Performance data of the prepared artificial board

[0055]

[0056]

[0057] A kind of high elastic artificial board, using the preparation method of a kind of high elastic artificial board as described above is prepared.

[0058] Drying device, it is applied to the drying section in the step (2) in the preparation method of a kind of high elastic artificial board as described above, and especially for the wood fiber (such as wood fiber silk, etc.) used as artificial board raw material, using the drying device, the agent such as preventing polydimethylsiloxane oxidation and reducing the dynamic cross-linking effect with fiber in the method can be maintained at low temperature drying to facilitate the construction of cross-linking network, can significantly improve the quality of board.

[0059] As Figure 1As shown, including the device body 1, the device body 1 is provided with a centrifugal drying turntable 21, the centrifugal drying turntable 21 is driven by a centrifugal motor 24, in this embodiment, the centrifugal motor 24 is a variable frequency motor (or speed adjustable motor), the centrifugal drying turntable 21 is provided with a plurality of drying air holes 3; the lower part of the centrifugal drying turntable 21 is provided with a drying air chamber 2; the drying air chamber 2 is communicated with a drying air inlet pipe 22, the drying air inlet pipe 22 is connected with a constant temperature air heater, in this example, the drying air inlet pipe 22 is also provided with a control valve; in this embodiment, in order to ensure the stability of the centrifugal drying turntable 21, the first rolling bearing 25 is arranged at the lower part of the centrifugal drying turntable 21 and is rotatably connected with the device body 1, and the boss 21 is arranged at the upper part of the centrifugal drying turntable 21 and is rotatably connected with the device body 1 through the second rolling bearing 20; the upper part of the centrifugal drying turntable 21 is provided with a turntable cover 6 and a feeding and air exhaust pipe, the turntable cover 6 is rotatably fixed on the feeding and air exhaust pipe through a rotating shaft 7; the lifting of the turntable cover 6 is controlled to realize the discharge of the drying material, in order to improve the smoothness of the lifting process, a ring 4 is arranged at the top of the centrifugal drying turntable 21 in this embodiment, and a horizontal ring 5 is correspondingly arranged at the lower outer side of the turntable cover 6. The lower part of the feeding and air exhaust pipe is arranged to be liftable, a telescopic pipe body is used, the lower segment 8 and the upper segment 9 can be relatively telescopic and displaced, the upper segment 9 of the feeding and air exhaust pipe is fixed to the support frame 15, in this embodiment, the support frame 15 is provided with a through hole, the lower part of the feeding and air exhaust pipe passes through the through hole, and the lower segment 8 of the feeding and air exhaust pipe is sleeved outside the upper segment 9 and can be relatively telescopic up and down, in order to improve the sealing performance and the smoothness of the telescopic process, a silica gel ring 10 is arranged in the through hole; when the lower segment 8 and the turntable cover 6 are driven, the embodiment scheme is as follows: a rack 18 is arranged at the outer side of the lower segment 8, a lifting motor 17 is used to drive the lifting, and the lifting motor 17 is fixed to the support frame 15 through a motor support 16; the upper segment 9 is communicated with an air exhaust pipe 11, the air exhaust pipe 11 is connected with an air exhaust pump; the top of the upper segment 9 is communicated with a feeding hopper 12, the feeding hopper 12 is fixed on the support frame 15 through a support; at the same time, an electric control material valve 14 is arranged on the feeding pipe. In order to improve the air exhaust uniformity, a plurality of air holes 23 are arranged at the lower part of the lower segment 8. In some embodiments, a blocking ring 19 can also be arranged to prevent the material from being thrown too far.

[0060] In use, the operating principle is as follows: the control of the electric control material valve 14 is opened to promote the wood fiber to be dried to be discharged from the feeding air exhaust pipe, and the feeding amount is controlled within a certain range by time control; after the control of the electric control material valve 14 is closed, the rotary disc cover 6 covers the centrifugal drying disc 21 at this time; the centrifugal motor 24 is started, the centrifugal drying disc 21 rotates, and the drying air inlet pipe 22 introduces constant temperature air below 80°C, and the wood fiber to be dried rolls upward under the action of centrifugal force, at this time, the constant temperature air is blown into the drying air outlet hole 3 during the rolling process, and is aligned for drying, the air exhaust pump of the air exhaust pipe 11 is started to exhaust air, the moisture is exhausted, the controller controls the centrifugal motor 24 to rotate at high speed for less than 10s, and then rotates at low speed for less than 5s, so that the wood fiber thrown to the high place of the centrifugal drying disc 21 falls back to the bottom of the centrifugal drying disc 21, and the drying air outlet hole 3 continues to blow in during the falling back process, and then the centrifugal motor 24 rotates at high speed again for less than 10s, so that the wood fiber at the bottom is thrown to the high place again, and after such reciprocating for many times, the drying and discharging are completed. The discharging process is as follows: the centrifugal motor 24 runs at low speed, and then the lifting motor 17 is started to promote the rotary disc cover 6 to rise to the high position, and after the lifting motor 17 stops, the centrifugal motor 24 rotates at high speed to promote the wood fiber to be centrifugally thrown from the top of the centrifugal drying disc 21 to the lower side of the blocking ring 19, and the discharging is completed, and then the centrifugal motor 24 becomes low speed during feeding, at this time the lifting motor 17 is started in reverse to promote the rotary disc cover 6 to descend and adhere to the top of the centrifugal drying disc 21, and then the control of the electric control material valve 14 is opened to discharge, and the above steps are repeated to complete the continuous drying of the material. The use of the device can significantly reduce manual operation, especially in feeding and discharging operations, and can reduce labor cost. At the same time, the device adopts the centrifugal method to promote the wood fiber to rotate at high speed in the centrifugal drying disc 21, and the constant temperature air is blown into the wood fiber through the air outlet hole 3 during the centrifugal rolling process to dry the wood fiber, and the wood fiber realizes continuous rolling drying during the centrifugal throwing and falling back process, which can significantly improve the uniformity of the internal and external moisture of the wood fiber, and greatly shorten the drying time at low temperature, and has good use effect.

Claims

1. A method for preparing a high-elasticity artificial board, characterized in that, comprising the following steps: (1) introducing boric acid and / or borax and / or small-molecule organic boric acid and its derivatives as a cross-linking agent into a hydroxyl-containing high-molecular polymer network to form dynamic bond cross-linking points, to obtain one or more dynamic coordination cross-linked high-molecular additives, and the coordination-driven cross-linking network is a system with reversible and dynamic characteristics, and will produce bond breaking and connection when subjected to a certain degree of external stimulus; (2) blending the artificial board raw materials with one or more dynamic coordination cross-linked high-molecular additives obtained in step (1), and after multiple additions and blending, drying to obtain the dynamic coordination cross-linked high-molecular additive pretreated artificial board raw materials; the drying is low-temperature rapid drying; (3) sizing the pretreated artificial board raw materials obtained in step (2), and then hot pressing to obtain a high-elasticity artificial board; the introduction process in step (1) refers to providing reaction conditions of the cross-linking agent and the hydroxyl-containing high-molecular polymer to form the dynamic bond cross-linking points in the high-molecular polymer network; the hydroxyl-containing high-molecular polymer is a hydroxyl-modified polyurethane and / or a hydroxyl-terminated polysiloxane and / or a modified epoxy resin. The artificial board raw materials are wood fibers and / or wood shavings and / or thin wood sheets.

2. The method of claim 1, wherein: The blending method in step (2) includes stirring or soaking or spraying or ultrasonic oscillation.

3. The method of claim 1, wherein the method further comprises: The weight ratio of the dynamic coordination cross-linked high-molecular additives to the artificial board raw materials in step (2) is 1-20:

100.

4. The method for preparing a high-elasticity engineered wood panel according to claim 1, characterized in that: In step (3), the glue used in the sizing step is urea-formaldehyde resin and / or melamine-modified urea-formaldehyde resin and / or MDI glue.

5. The method of claim 1, wherein the method further comprises: In step (2), a drying device is used for drying and water removal, and the moisture content is controlled to be below 10%.

6. The method of claim 1, wherein: The drying device used in the drying section in step (2) is:

7. The method of claim 1, wherein the method further comprises the step of: including a device body, a centrifugal drying turntable is arranged in the device body, a plurality of drying gas outlets are arranged on the centrifugal drying turntable; a drying gas chamber is arranged below the centrifugal drying turntable; the drying gas chamber is communicated with a drying gas inlet pipe; a turntable cover and a feeding and gas extraction pipe are arranged above the centrifugal drying turntable, the turntable cover is rotatably arranged on the feeding and gas extraction pipe; the lower part of the feeding and gas extraction pipe is liftably arranged, the upper part thereof is communicated with a gas extraction pipe, and the top part thereof is communicated with a feeding hopper. ​ Prepared by using the method for preparing a high-elasticity artificial board according to any one of claims 1-7.

8. A high-resilience artificial board material, characterized by: ​

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