High-elastic artificial board, preparation method and drying device

Abstract

The invention 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 method comprises the following steps: (1) directly introducing a cross-linking agent into a hydroxyl-containing high-molecular polymer network to form a dynamic bond cross-linking point so as to obtain one or more dynamic coordination cross-linked high-molecular additives; (2) blending an artificial board raw material with one or more dynamic coordination cross-linked polymer additives obtained in the step (1), adding and blending for multiple times, and drying; and (3) gluing the pretreated artificial board raw material obtained in the step (2), and then carrying out hot pressing to obtain the high-elastic artificial board. The high-elastic artificial board prepared by the method has the advantages that key fracture and connection can be generated when the high-elastic artificial board is subjected to external stimulation to a certain degree, so that the board is quickly changed into a high-elastic hard solid. By using the drying device, the drying uniformity can be obviously improved, and the drying time is shortened.

Description

Technical Field

[0001] The invention belongs to the technical field of artificial board manufacturing, and in particular relates to a high-elastic artificial board, a preparation method and a drying device. Background Art

[0002] Wood flooring is a popular floor decoration material for homes and commercial spaces around the world. It is an indispensable carrier in the life of people in the new era. It contains the yearning and pursuit for a better life and creates a comfortable and warm space. After nearly 30 years of development, my country's wood flooring industry has made significant progress in technological innovation and brand building, and has now formed a relatively complete industrial system. In recent years, after reaching a staged historical peak, my country's wood flooring production has shown a slow downward trend. The benefits of most products in this field have declined, and the industry development situation is grim. Science is the first driving force for the development of the industry. Only by constantly innovating and bringing forth new ideas based on people's needs can the current dilemma of the wood flooring industry be broken.

[0003] In recent years, national sports and home fitness have become popular, and people's enthusiasm for sports is increasing day by day. The floor of the sports area has become an important factor affecting people's walking comfort. In order to meet people's demand for high-quality sports areas, highly elastic floors are urgently needed to be innovatively developed. This kind of floor allows people to quickly turn the floor board into a highly elastic hard solid when they are doing intense sports or sports competitions. Summary of the invention

[0004] In view of the above shortcomings, the present invention 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 object, the present invention adopts the following technical scheme:

[0006] A method for preparing a high-elastic artificial sheet material,

[0007] The steps include:

[0008] (1) Small molecules or inorganic electrolytes are directly introduced as crosslinking agents into a hydroxyl-containing polymer network to form dynamic bond crosslinking points, thereby obtaining one or more dynamic coordination crosslinking polymer additives. The coordination-driven crosslinking network is a novel system with reversible and dynamic characteristics, and bond breaking and connection will occur when subjected to a certain degree of external stimulation;

[0009] (2) blending the raw material for artificial board with one or more dynamically coordinated cross-linked polymer additives obtained in step (1), adding and blending for multiple times, and then drying to obtain the raw material for artificial board pretreated with the dynamically coordinated cross-linked polymer additive;

[0010] (3) Gluing the pretreated artificial board raw material obtained in step (2), and then hot pressing to obtain a high-elastic artificial 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 introduction process in step (1) refers to providing reaction conditions between the small molecule or inorganic electrolyte crosslinking agent and the hydroxyl-containing high molecular polymer to form the dynamic bond crosslinking points in the high molecular polymer network.

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

[0013] Optionally, the raw materials of the artificial board are wood fibers and / or wood shavings and / or wood chips.

[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 cross-linking polymer additive to the raw material of the artificial board in step (2) is 1 to 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 artificial boards.

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

[0017] A high-elastic artificial board is prepared using the above-mentioned method for preparing a high-elastic artificial board. A drying device is used in the drying section in step (2) of the above-mentioned method for preparing a high-elastic artificial board;

[0018] It includes a device body, wherein a centrifugal drying turntable is arranged inside the device body, and a plurality of drying air outlet holes are arranged on the centrifugal drying turntable; a drying air chamber is arranged below the centrifugal drying turntable; the drying air chamber is connected to a drying air inlet pipe; a turntable cover and a feeding and exhaust pipe are arranged above the centrifugal drying turntable, and the turntable cover can be rotatably arranged on the feeding and exhaust pipe; the lower part of the feeding and exhaust pipe can be raised and lowered, and the upper part thereof is connected to an exhaust pipe, and the top thereof is connected to a feeding funnel.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The method for preparing the highly elastic artificial board of the present invention establishes a coordination-driven cross-linking network, which is a novel system with reversible and dynamic characteristics. Under external stimulation, it can be transformed from a conventional wooden floor to a highly elastic hard floor without the need for additional energy. The floor has a comfortable walking feeling and a sense of movement, and is suitable for decoration, flooring and other fields in indoor places, public places, gymnasiums and the like.

[0021] 2. The method for preparing the highly elastic artificial board of the present invention adds a dynamically coordinated cross-linked polymer additive while retaining the original process of the wood floor. The additive is applicable to the existing conventional wood floor manufacturing process, and no additional modification or change is required to the equipment, thereby reducing the cost of new product development and facilitating the large-scale promotion of new products.

[0022] 3. The preparation method of the artificial board with high elasticity of the present invention, the dynamic coordination cross-linking polymer additive is compatible with most artificial board adhesives and additives, and different types of wood floor products can be customized according to needs.

[0023] 4. In the method for preparing the highly elastic artificial board of the present invention, the dynamically coordinated cross-linked polymer additive adds a cross-linked network between multiple substances such as adhesives, artificial board raw materials, additives, etc., effectively improving the bonding performance of the adhesive and the physical properties of the artificial board. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below.

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

[0026] Figure 2a to Figure 2b This is the test report of Comparative Example 2 of the present invention;

[0027] Figure 3a to Figure 3b This is the test report of Example 1 of the present invention. DETAILED DESCRIPTION

[0028] The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "inside", "front", "back", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0030] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] A method for preparing a high-elastic artificial sheet material comprises the following steps:

[0032] (1) Small molecules or inorganic electrolytes are directly introduced as crosslinking agents into a hydroxyl-containing polymer network to form dynamic bond crosslinking points, thereby obtaining one or more dynamic coordination crosslinking polymer additives. The coordination-driven crosslinking network is a novel system with reversible and dynamic characteristics, and bond breaking and connection will occur when subjected to a certain degree of external stimulation;

[0033] (2) blending the raw material for artificial board with one or more dynamically coordinated cross-linked polymer additives obtained in step (1), adding and blending for multiple times, and then drying to obtain the raw material for artificial board pretreated with the dynamically coordinated cross-linked polymer additive;

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

[0035] 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 introduction process in step (1) refers to providing reaction conditions between the small molecule or inorganic electrolyte crosslinking agent and the hydroxyl-containing high molecular polymer to form the dynamic bond crosslinking points in the high molecular polymer network.

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

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

[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-linking polymer additive to the raw material of the artificial board in step (2) is 1 to 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 general process glue for artificial boards.

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

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

[0042] Embodiment 1 of a method for preparing a high-elastic artificial sheet material of the present invention comprises the following steps:

[0043] (1) dissolving 20 parts of boric acid in 20 parts of aqueous solution, and magnetically stirring for 60 minutes to uniformly mix the solution to obtain a boric acid aqueous solution;

[0044] (2) dispersing 100 parts of hydroxyl-terminated polydimethylsiloxane in 100 parts of propylene glycol, and magnetically stirring for 60 minutes to uniformly mix the mixture, thereby obtaining a dynamically coordinated cross-linked polymer additive;

[0045] (3) Blending the eucalyptus fiber with the dynamically coordinated cross-linked polymer additive and boric acid aqueous solution obtained in step (1), the blending operation method is as follows: the two solutions are blended at room temperature, and an emulsion is formed under vigorous stirring. After standing, the emulsion will be stratified, so the mixture is sprayed while stirring to ensure uniform mixing of the additive and boric acid water. After multiple additions and blending, the mixture is dried. In this scheme, the drying step is more critical: it is mainly to prevent the oxidative decomposition of the above reagents and to ensure uniform drying inside and outside the wood fiber (the quality of this drying step will affect the proportion of hydroxyl-terminated polydimethylsiloxane bound to the fiber, that is, the construction effect of the cross-linked network, and thus directly affect the high elasticity of the board. Therefore, the purpose of drying is to dry at low temperature and minimize the drying time, and then proceed to the next step of gluing and board making. In this embodiment, the special drying device of the present invention is preferred, which controls the drying temperature below 80°C (optionally 55°C, 60°C, 65°C and 70°C, etc.), and then adopts a combination of negative pressure suction + high pressure jet + centrifugal to achieve low temperature and fast drying. Rapid drying, at low temperature to prevent oxidation of the agent and increase the drying speed, can also ensure uniform moisture content inside and outside the fiber, avoiding the disadvantages of high-temperature drying in traditional dryers, where the outer layer of the fiber is over-dried while the moisture content of the inner layer is still high, which affects the construction effect of the cross-linked network. The specific gravity of eucalyptus fiber, dynamically coordinated cross-linked polymer additive, and boric acid aqueous solution is 600:40:8, and the moisture content of eucalyptus fiber after drying is 10%. Under the action of hydrogen bonding, hydroxyl-terminated polydimethylsiloxane is bound to the fiber, and based on the cross-linking effect of borate particles, dihydroxy polydimethylsiloxane is dynamically cross-linked with the fiber to obtain eucalyptus fiber pretreated with dynamically coordinated cross-linked polymer additives;

[0046] (4) MDI glue is applied to the pretreated eucalyptus fiber obtained in step (2), wherein the ratio of MDI glue to pretreated eucalyptus fiber is 1:20, and then hot-pressed to obtain a high-elastic artificial board. The artificial board prepared in Example 1 is tested for relevant indicators.

[0047] Comparative Example 1

[0048] This comparative example 1 uses a conventional fiberboard preparation method, including the following steps:

[0049] (1) drying the eucalyptus fiber, wherein the moisture content of the eucalyptus fiber after drying is 10%;

[0050] (2) Applying MDI glue to the pretreated eucalyptus fiber obtained in step (1), wherein the ratio of MDI glue to pretreated eucalyptus fiber is 1:20, and then hot pressing to obtain a high-elastic artificial board. The artificial board prepared in Comparative Example 2 is tested for relevant indicators.

[0051] Comparative Example 2

[0052] The difference between this comparative example 2 and example 1 is that: a conventional dryer is used to dry the eucalyptus fiber at the same temperature until the average moisture content of the eucalyptus fiber is 10% (because the conventional dryer is static drying, not only the drying time required is longer, but also the moisture content inside and outside the fiber will be 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 artificial board prepared in comparative example 2 is tested for relevant indicators.

[0053] The elastic modulus and impact toughness of the artificial boards of Example 1, Comparative Example 1 and Comparative Example 2 were tested, and the mechanical properties test was carried out according to GB / T 17657-2022 "Test Methods for Physical and Chemical Properties of Artificial Boards and Facing Artificial Boards", 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 Example 1 and Comparative Example 2, indicating that the experimental board has good toughness and better deformation ability under external force impact, and the increase in internal bonding strength indicates that the addition of this kind of dynamically coordinated cross-linked polymer additive has an enhancing effect on the adhesive of conventional fiberboard.

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

[0055]

[0056]

[0057] A high-elastic artificial board is prepared using the high-elastic artificial board preparation method as described above.

[0058] The drying device is applied to the drying section in the step (2) of the method for preparing a high-elastic artificial board as described above, and especially when the raw material of the artificial board used is wood fiber (such as wood fiber filaments, etc.), the drying device can be used to prevent the oxidation of agents in the method, such as polydimethylsiloxane, and reduce the dynamic cross-linking effect with the fiber, so as to maintain low-temperature drying, which is conducive to the construction of the cross-linking network and can significantly improve the quality of the board.

[0059] like Figure 1As shown, the device comprises a main body 1, wherein a centrifugal drying turntable 21 is arranged in the main body 1, and 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 a motor with adjustable speed), and a plurality of drying air outlets 3 are arranged on the centrifugal drying turntable 21; a drying air chamber 2 is arranged below the centrifugal drying turntable 21; the drying air chamber 2 is connected to a drying air inlet pipe 22, and the drying air inlet pipe 22 is externally connected to a constant temperature air heater. In this example, a control valve is also arranged on the drying air inlet pipe 22; in this embodiment, in order to ensure the stability of the operation of the centrifugal drying turntable 21, A first rolling bearing 25 is arranged at its lower part and is rotatably connected to the device body 1. At the same time, a boss 21 is arranged on the upper part of the centrifugal drying turntable 21, and the boss 21 is rotatably connected to the device body 1 through a second rolling bearing 20; a turntable cover 6 and a feeding and exhaust pipe are arranged above the centrifugal drying turntable 21, and the turntable cover 6 can be rotatably fixed on the feeding and exhaust pipe through a rotating shaft 7; drying and discharging are achieved by controlling the lifting and lowering of the turntable cover 6. In order to improve the smoothness of the lifting process, a circle of convex rings 4 are arranged on the top of the centrifugal drying turntable 21 in this embodiment, and the lower outer side of the turntable cover 6 is also correspondingly arranged as a horizontal circle 5. The lower part of the feeding and exhausting pipe can be raised and lowered, and a telescopic pipe body is used, and its lower section 8 and upper section 9 can be relatively telescopically displaced. The upper section 9 of the feeding and exhausting pipe is fixed to the support frame 15. In this embodiment, the support frame 15 is provided with a through hole, and the lower part of the feeding and exhausting pipe passes through the through hole. At the same time, the lower section 8 of the feeding and exhausting pipe is sleeved on the outside of the upper section 9 and can be telescopically displaced up and down relative to the upper section 9. In order to improve the sealing performance and the smoothness of telescopicity, in this embodiment, a silicon The rubber ring 10; when driving the lower section 8 and the turntable cover 6, the scheme of this embodiment is as follows: a rack 18 is arranged on the outer side of the lower section 8, and the lifting and lowering is driven by the lifting motor 17, and the lifting motor 17 is fixed to the support frame 15 through the motor bracket 16; the upper section 9 is connected with the exhaust pipe 11, and the exhaust pipe 11 is connected to the exhaust pump; the top of the upper section 9 is connected with the feed funnel 12, and the feed funnel 12 is fixed to the support frame 15 through the bracket; at the same time, an electric control material valve 14 is arranged on the feed pipe. In order to improve the uniformity of the exhaust, in this embodiment, a plurality of air holes 23 are arranged at the lower part of the lower section 8. In some embodiments, a retaining ring 19 can also be provided to prevent the material from being thrown out too far.

[0060] When in use, the operating principle is as follows: the electronically controlled material valve 14 is controlled to open to cause the wood fiber to be dried to be discharged from the feeding and exhausting pipe, and the feeding amount is controlled within a certain range by time; after the electronically controlled material valve 14 is controlled to be closed, the turntable cover 6 is covered on the centrifugal drying turntable 21; the centrifugal motor 24 is started, the centrifugal drying turntable 21 rotates, and at the same time, the drying air inlet pipe 22 is introduced with constant temperature air below 80°C, and the wood fiber to be dried rolls upward under the centrifugal action. At this time, the constant temperature air is discharged from the drying outlet during the rolling process. The centrifugal motor 24 is controlled by the controller to rotate at a high speed for less than 10 seconds, and then rotates at a low speed for less than 5 seconds, so that the wood fibers thrown to the high place of the centrifugal drying turntable 21 fall back to the bottom of the centrifugal drying turntable 21. During the falling process, the drying outlet hole 3 is continuously blown in, and then the centrifugal motor 24 rotates at a high speed for less than 10 seconds, so that the wood fibers at the bottom are thrown to a high place again. After repeated reciprocation, the drying and discharging are completed. The discharging process is as follows: the centrifugal motor 24 runs at a low speed, and then the lifting motor 17 is started, prompting the turntable cover 6 to rise to a high position. After the lifting motor 17 stops, the centrifugal motor 24 rotates at a high speed, prompting the wood fiber to be centrifugally thrown out from the top of the centrifugal drying turntable 21 to the bottom of the retaining ring 19 to complete the discharging. Then, when feeding, the centrifugal motor 24 becomes low speed, and at this time, the lifting motor 17 is reversely started, prompting the turntable cover 6 to descend and fit with the top of the centrifugal drying turntable 21, and then the electronically controlled material valve 14 is controlled to open the material, and the above steps are repeated to complete the continuous drying of the material. The use of this device can significantly reduce manual work, especially in operations such as feeding and discharging, and everyone reduces labor costs. At the same time, the device adopts a centrifugal method to prompt the wood fiber to flip at a high speed in the centrifugal drying turntable 21. At the same time, during the centrifugal flipping process, constant temperature air is blown into the air outlet 3 to dry the wood fiber. The wood fiber is continuously flipped and dried during the centrifugal outward swing and falling process, which can significantly improve the uniformity of moisture drying inside and outside the wood fiber, and can also greatly shorten the drying time at low temperature, and the use effect is good.

Claims

1. A method for preparing a high-elastic artificial sheet, characterized in that: The steps include: (1) Small molecules or inorganic electrolytes are directly introduced as crosslinking agents into a hydroxyl-containing polymer network to form dynamic bond crosslinking points, thereby obtaining one or more dynamic coordination crosslinking polymer additives. The coordination-driven crosslinking network is a novel system with reversible and dynamic characteristics, and bond breaking and connection will occur when subjected to a certain degree of external stimulation; (2) blending the raw material for artificial board with one or more dynamically coordinated cross-linked polymer additives obtained in step (1), adding and blending for multiple times, and then drying to obtain the raw material for artificial board pretreated with the dynamically coordinated cross-linked polymer additive; (3) Gluing the pretreated artificial board raw material obtained in step (2), and then hot pressing to obtain a high-elastic artificial board.

2. A method for preparing a high-elastic artificial sheet according to claim 1, characterized in that; 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 introduction process in step (1) refers to providing reaction conditions between the small molecule or inorganic electrolyte crosslinking agent and the hydroxyl-containing high molecular polymer to form the dynamic bond crosslinking point in the high molecular polymer network.

3. The method for preparing a high-elastic artificial sheet according to claim 1, characterized in that: The hydroxyl-containing high molecular polymer is hydroxyl-modified polyurethane and / or hydroxyl-terminated polysiloxane and / or modified epoxy resin.

4. The method for preparing a high-elastic artificial sheet according to claim 1, characterized in that: The raw materials of the artificial board are wood fibers and / or wood shavings and / or wood chips.

5. The method for preparing a high-elastic artificial sheet according to claim 1, characterized in that: The blending method in step (2) includes: stirring, soaking, spraying or ultrasonic vibration.

6. The method for preparing a high-elastic artificial sheet according to claim 1, characterized in that: The weight ratio of the dynamic coordination cross-linking polymer additive to the raw material of the artificial board in the step (2) is 1 to 20:

100.

7. The method for preparing a high-elastic artificial board according to claim 1, characterized in that: In the 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 artificial boards.

8. The method for preparing a high-elastic artificial board according to claim 1, characterized in that: In the step (2), a drying device is used to dry and remove water, and the moisture content is controlled to be below 10%.

9. A high-elastic artificial sheet, characterized in that: The high-elastic artificial board is prepared using the method for preparing the high-elastic artificial board as described in any one of claims 1 to 8.

10. Drying device, characterized in that: Applicable to the drying section in step (2) of the method for preparing a high-elastic artificial board as claimed in any one of claims 1 to 8; It includes a device body, wherein a centrifugal drying turntable is arranged inside the device body, and a plurality of drying air outlet holes are arranged on the centrifugal drying turntable; a drying air chamber is arranged below the centrifugal drying turntable; the drying air chamber is connected to a drying air inlet pipe; a turntable cover and a feeding and exhaust pipe are arranged above the centrifugal drying turntable, and the turntable cover can be rotatably arranged on the feeding and exhaust pipe; the lower part of the feeding and exhaust pipe can be raised and lowered, and the upper part thereof is connected to an exhaust pipe, and the top thereof is connected to a feeding funnel.

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