Fiberboard preparation process

Abstract

The embodiment of the invention provides a fiberboard preparation process, and belongs to the technical field of building decoration products. The preparation process comprises the following steps: step s100, sequentially carrying out sulfamic acid solution treatment, acetic acid solution treatment, alkaline solution treatment and vacuum treatment on natural plant fibers to obtain pretreated fibers; s200, an adhesive is prepared; s300, the pretreated fibers and the adhesive are mixed to obtain a mixture, and the mixture is laid and formed to obtain a plate blank; and s400, the plate blank is subjected to hot pressing and curing. Natural plant fibers are used as raw materials, and the raw materials are subjected to sulfamic acid solution treatment, acetic acid solution treatment, alkali solution treatment and vacuum treatment, so that the finally obtained plate is more stable in structure, and the volatilization rate of VOC (volatile organic compounds) and formaldehyde is lower.

Description

Technical Field

[0001] The present invention relates to the technical field of building decoration products, in particular to a fiberboard preparation process. Background Art

[0002] Fiberboard is a man-made board material widely used in furniture, construction, and decoration. Traditional fiberboard production typically uses formaldehyde-containing urea-formaldehyde or phenol-formaldehyde resins as adhesives. This causes the finished boards to continuously release formaldehyde and other volatile organic compounds (VOCs) during use, posing a threat to human health and the environment. With growing environmental awareness, market demand for low-VOC, zero-formaldehyde fiberboard is increasing.

[0003] Although some low-formaldehyde or formaldehyde-free adhesives have been studied in the prior art, they still face problems such as high cost, insufficient bonding strength, and complex production processes. Therefore, it is of great significance to develop a low-VOC, zero-formaldehyde fiberboard that is both environmentally friendly, economical, and practical. Summary of the Invention

[0004] The objects of the present invention include, for example, providing a fiberboard preparation process, using natural plant fibers as raw materials, and subjecting the raw materials to aminosulfonic acid solution treatment, acetic acid solution treatment, alkaline solution treatment and vacuum treatment, so that the structure of the final board is more stable and the volatilization rate of VOC and formaldehyde is lower.

[0005] The embodiments of the present invention can be implemented as follows:

[0006] In a first aspect, the present invention provides a fiberboard preparation process comprising the following steps:

[0007] Step s100: sequentially treating the natural plant fiber with a sulfamic acid solution, an acetic acid solution, an alkaline solution, and a vacuum treatment to obtain pretreated fiber;

[0008] Step s200: preparing adhesive;

[0009] Step s300: mixing the pretreated fibers with the adhesive to obtain a mixture, and paving and forming the mixture to obtain a slab;

[0010] Step s400: hot pressing and curing the slab.

[0011] In the above technical solution, treating the natural plant fibers with aminosulfonic acid solution can enhance the bonding force between cellulose and lignin, preventing the density board from swelling and deforming after absorbing water, and maintaining the structural integrity of the density board. In addition, subsequent treatment with acetic acid solution and alkaline solution can fix the bonding force between cellulose and lignin, preventing the increase or decrease in bonding force from causing changes in the size of the density board. At the same time, it can reduce the water retention capacity of the pulverized fibers, allowing the density board to dry quickly after soaking in water, maintaining the structural stability of the density board. Vacuum treatment is then performed to evenly mix and penetrate the various components of the pulverized fibers, reducing the water absorption and water retention capacity of the pulverized fibers and improving the hydrophobic properties of the density board. The subsequent addition of adhesive and hot-press curing can make the resulting board structure more stable and have lower VOC and formaldehyde volatility.

[0012] In an optional embodiment, the sulfamic acid solution treatment method includes: crushing natural plant fibers to a particle size of 1 to 3 mm to obtain crushed fibers, then adding sulfamic acid solution, standing and drying to obtain dry fibers with a moisture content of 5 to 7%.

[0013] In the above technical solution, by controlling the fiber particle size to 1 to 3 mm, the surface area of ​​the crushed fiber can be increased, which is beneficial for the subsequent treatment of the aminosulfonic acid solution. By controlling the moisture content, it is convenient for the early mixing and can also reduce the water required for the later curing and molding, thereby reducing energy consumption.

[0014] Optionally, the natural plant fiber may be, for example but not limited to, wood, bamboo, straw, etc.

[0015] In an optional embodiment, the concentration of the sulfamic acid solution is 65-75 mg / L, the amount of the sulfamic acid solution added is 40-45% of the weight of the pulverized fiber, and the standing time is 2-3 days.

[0016] In an optional embodiment, the acid solution treatment method includes: adding 20-25% acetic acid solution by weight of the dry fiber to the dry fiber, stirring, and standing at room temperature and pressure for 20-24 hours; wherein the volume concentration of the acetic acid solution is 3-5%.

[0017] In an optional embodiment, the method of treating with alkaline solution comprises: continuing to add sodium hydroxide solution with a concentration of 40-45% of the dry fiber weight to the solution treated with acid solution, stirring, standing for 8-10 hours, and drying to a water content of 8-10% to obtain acid-base treated fiber; wherein the alkaline solution is a sodium hydroxide solution with a concentration of 32-36 mg / L.

[0018] In an optional embodiment, the process further includes placing the alkali-treated fiber in a heating kettle, adjusting the vacuum degree to -85 to -90 kPa, heating to 270 to 290°C at a rate of 2 to 3°C / min, keeping the temperature for 30 to 40 minutes, adjusting to normal pressure, keeping the temperature for 15 to 25 minutes, and naturally cooling to 50 to 70°C to obtain high-pressure treated fiber.

[0019] In an optional embodiment, in step s200, the ingredients of the adhesive include, by weight, 5 to 10 parts of soy protein glue, 42 to 44 parts of chlorinated polypropylene resin, 27 to 29 parts of polysiloxane resin, 21 to 23 parts of acrylic emulsion, 16 to 18 parts of polydimethylsiloxane, and 5 to 7 parts of nano zinc oxide.

[0020] In the above technical solution, adding multiple ingredients to the adhesive can improve the bonding ability between fibers and increase the strength of the density board. At the same time, it can also improve the hydrophobic and antibacterial properties of the density board, delay the aging of the density board, and extend the service life of the density board.

[0021] In an optional embodiment, the adhesive further contains 0.5 to 1 parts by weight of additives, wherein the additives include natural antibacterial agents, flame retardants, and VOC adsorbents.

[0022] In an optional embodiment, in step s300: the amount of the adhesive added is 16-18% of the weight of the pretreated fiber.

[0023] In an optional embodiment, in step s400: the pressure of the hot pressing curing is 60-65 MPa; wherein, the temperature is first heated to 220-240°C at a rate of 2-3°C / min, kept warm for 25-35 minutes, and then slowly lowered to 170-190°C and kept warm for 15-20 minutes.

[0024] In the above technical solution, the pressure is first increased, the temperature is quickly raised, and the density board is hot-pressed to promote the adhesive in the density board to evenly adhere to the surface of the crushed fibers. At the same time, the moisture in the slab can be removed, and the bonding ability between the crushed fibers is increased. The temperature is slowly lowered and then kept warm again to promote uniform film formation of the adhesive and improve the adhesive ability. Finally, the temperature is naturally lowered to room temperature to evenly solidify the adhesive in the density board, thereby increasing the strength and wear resistance of the density board.

[0025] The beneficial effects of the embodiments of the present invention include, for example:

[0026] Using natural plant fibers as raw materials, and subjecting the raw materials to aminosulfonic acid solution treatment, acetic acid solution treatment, alkaline solution treatment and vacuum treatment, can make the structure of the final board more stable and the volatility of VOC and formaldehyde lower. DETAILED DESCRIPTION

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. It should be noted that the features in the embodiments of the present invention can be combined with each other unless there is any conflict.

[0028] This embodiment provides a fiberboard preparation process, comprising the following steps:

[0029] Step s100: sequentially treating the natural plant fiber with a sulfamic acid solution, an acetic acid solution, an alkaline solution, and a vacuum treatment to obtain pretreated fiber;

[0030] Step s200: preparing adhesive;

[0031] Step s300: mixing the pretreated fibers with an adhesive to obtain a mixture, and paving and forming the mixture to obtain a slab;

[0032] Step s400: hot pressing and curing the slab.

[0033] Based on the above technical solution, treating natural plant fibers with aminosulfonic acid solution can enhance the bonding force between cellulose and lignin, preventing the density board from swelling and deformation after absorbing water, and maintaining the structural integrity of the density board. In addition, subsequent treatment with acetic acid solution and alkaline solution can fix the bonding force between cellulose and lignin, preventing the increase or decrease in bonding force from causing changes in the size of the density board. At the same time, it can reduce the water retention capacity of the crushed fibers, allowing the density board to dry quickly after soaking in water and maintaining the structural stability of the density board. Vacuum treatment is then performed to evenly mix and penetrate the various components of the crushed fibers, reducing the water absorption and water retention capacity of the crushed fibers and improving the hydrophobic properties of the density board. The subsequent addition of adhesives for hot pressing and curing can make the final board structure more stable and have lower VOC and formaldehyde volatility.

[0034] In this embodiment, the optional method of treating with sulfamic acid solution includes: crushing natural plant fibers to a particle size of 1 to 3 mm to obtain crushed fibers, then adding sulfamic acid solution, standing and drying to obtain dry fibers with a moisture content of 5 to 7%.

[0035] Based on the above technical solution, by controlling the fiber particle size to 1 to 3 mm, the surface area of ​​the crushed fiber can be increased, which is beneficial for the subsequent treatment of the aminosulfonic acid solution. By controlling the moisture content, it is convenient for the early mixing and can also reduce the water required for the later curing and molding, thereby reducing energy consumption.

[0036] Optionally, the natural plant fiber may be, for example but not limited to, wood, bamboo, straw, etc.

[0037] In this embodiment, optionally, the concentration of the sulfamic acid solution is 65-75 mg / L, the amount of the sulfamic acid solution added is 40-45% of the weight of the pulverized fibers, and the standing time is 2-3 days.

[0038] In this embodiment, the acid solution treatment method optionally includes: adding acetic acid solution of 20-25% by weight of the dry fiber to the dry fiber, stirring, and standing at room temperature and pressure for 20-24 hours; wherein the volume concentration of the acetic acid solution is 3-5%.

[0039] In this embodiment, optionally, the method of alkaline solution treatment includes: continuing to add 40-45% of the dry fiber weight of sodium hydroxide solution to the solution after acid solution treatment, stirring, standing for 8-10 hours, and drying to a water content of 8-10% to obtain acid-base treated fiber; wherein the alkaline solution is a sodium hydroxide solution with a concentration of 32-36 mg / L.

[0040] In this embodiment, optionally, the following further comprises: placing the alkali-treated fiber in a heating kettle, adjusting the vacuum degree to -85 to -90 kPa, heating to 270 to 290°C at a rate of 2 to 3°C / min, keeping the temperature for 30 to 40 minutes, adjusting to normal pressure, keeping the temperature for 15 to 25 minutes, and naturally cooling to 50 to 70°C to obtain high-pressure treated fiber.

[0041] In this embodiment, optionally, in step s200, the components of the adhesive include, by weight, 5 to 10 parts of soy protein glue, 42 to 44 parts of chlorinated polypropylene resin, 27 to 29 parts of polysiloxane resin, 21 to 23 parts of acrylic emulsion, 16 to 18 parts of polydimethylsiloxane, and 5 to 7 parts of nano zinc oxide.

[0042] Based on the above technical solution, adding multiple ingredients to the adhesive can improve the bonding ability between fibers and increase the strength of the density board. At the same time, it can also improve the hydrophobic and antibacterial properties of the density board, delay the aging of the density board, and extend the service life of the density board.

[0043] In this embodiment, the adhesive may optionally further contain 0.5 to 1 parts by weight of additives, wherein the additives include natural antimicrobial agents, flame retardants, and VOC adsorbents.

[0044] In this embodiment, optionally, in step s300 , the amount of adhesive added is 16-18% of the weight of the pretreated fiber.

[0045] In this embodiment, optionally, in step s400: the pressure of hot pressing curing is 60-65 MPa; wherein, first heating to 220-240°C at a rate of 2-3°C / min, keeping warm for 25-35 minutes, then slowly cooling to 170-190°C, keeping warm for 15-20 minutes.

[0046] Based on the above technical solution, the pressure is first increased, the temperature is quickly raised, and the density board is hot-pressed to promote the adhesive in the density board to evenly adhere to the surface of the crushed fibers. At the same time, it can remove moisture in the slab and increase the bonding ability between the crushed fibers. The temperature is slowly lowered and then kept warm again to promote uniform film formation of the adhesive and improve the adhesive ability. Finally, the temperature is naturally lowered to room temperature to allow the adhesive in the density board to evenly solidify, thereby increasing the strength and wear resistance of the density board.

[0047] Example 1

[0048] Step s100: Mix wood and straw in a weight ratio of 4:1, crush the mixed wood and straw into crushed fibers with a particle size of 2 mm, add aminosulfonic acid solution with a concentration of 70 mg / L and an addition amount of 40% of the weight of the crushed fibers to the crushed fibers, stir evenly, let it stand and soak for 3 days, and freeze-dry the wet crushed fibers to a moisture content of 6% to obtain dry fibers.

[0049] Step s200: Add an acetic acid solution with a concentration of 70 mg / L and an addition amount of 4% of the dry fiber weight to the dry fiber, stir evenly, and let it stand at room temperature and pressure for 24 hours. Then add a sodium hydroxide solution with a concentration of 30 mg / L and an addition amount of 5% of the dry fiber weight, stir evenly, let it stand for 10 hours, and dry to a moisture content of 8% to obtain acid-base treated fiber.

[0050] Step s300: Place the acid-base treated fiber in a heating kettle, adjust the vacuum degree to -90 kPa, heat to 270°C at a rate of 3°C / min, keep warm for 30 minutes, adjust to normal pressure, keep warm for 20 minutes, and naturally cool to 70°C to obtain high-pressure treated fiber.

[0051] Step s400: uniformly add an adhesive comprising 10 parts by weight of soybean protein glue, 40 parts by weight of chlorinated polypropylene resin, 25 parts by weight of polysilicon nitrogen resin, 20 parts by weight of acrylic emulsion, 15 parts by weight of polydimethylsiloxane, 5 parts by weight of nano zinc oxide and 1 part by weight of VOC adsorbent activated carbon to the high-pressure treated fiber, in an amount of 20% by weight of the high-pressure treated fiber, and stir evenly to obtain the sizing-treated fiber.

[0052] Step s500: Lay the sizing treated fibers and form the blanks, hot press the blanks at a pressure of 60 MPa, heat to 230°C at a rate of 3°C / min, keep warm for 30 minutes, then slowly cool to 180°C and keep warm for 20 minutes to obtain a density of 830-900 kg / m 3 fiberboard.

[0053] Example 2

[0054] The difference from Example 1 is that the ratio of plant raw materials, trees and straw, is 5:1, and the rest is the same.

[0055] Example 3

[0056] The difference from Example 1 is that the ingredients are 15 parts of soybean protein glue, 45 parts of chlorinated polypropylene resin, 35 parts of polysiloxane resin, 25 parts of acrylic emulsion, 20 parts of polydimethylsiloxane, and 10 parts of nano zinc oxide, and the rest are the same.

[0057] Comparative Example 1

[0058] The difference between Comparative Example 1 and Example 1 is that

[0059] Step s100: mixing wood and straw in a weight ratio of 4:1, and crushing the mixed wood and straw into crushed fibers with a particle size of 2 mm.

[0060] Step s200: Add acetic acid solution with a concentration of 70 mg / L and an addition amount of 4% of the weight of the pulverized fiber to the pulverized fiber, stir evenly, and let it stand at room temperature and pressure for 24 hours. Then add sodium hydroxide solution with a concentration of 30 mg / L and an addition amount of 5% of the dry fiber weight, stir evenly, let it stand for 10 hours, and dry to a moisture content of 8% to obtain acid-base treated fiber.

[0061] Comparative Example 2

[0062] The difference between Comparative Example 2 and Example 1 is that step s200 is not performed.

[0063] Comparative Example 3

[0064] Comparative Example 3 differs from Example 1 in that step s300 is not performed.

[0065] The properties of the fiberboards provided in Examples 1 to 3 and Comparative Examples 1 to 3 were tested respectively, as shown in Table 1.

[0066] Table 1 Properties of fiberboard

[0067]

[0068]

[0069] As can be seen from Table 1, the fiber preparation process provided in this embodiment can obtain a more stable fiberboard structure with a formaldehyde emission of ≤0.05 mg / m 3 , VOC emissions ≤ 0.1mg / m 3 , low formaldehyde emission, low VOC emission, good environmental protection. At the same time, the preparation process is simple and the preparation cost is low.

[0070] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A fiberboard preparation process, characterized in that: The steps include: Step s100: sequentially treating the natural plant fiber with a sulfamic acid solution, an acetic acid solution, an alkaline solution, and a vacuum treatment to obtain pretreated fiber; Step s200: preparing adhesive; Step s300: mixing the pretreated fibers with the adhesive to obtain a mixture, and paving and forming the mixture to obtain a slab; Step s400: hot pressing and curing the slab.

2. The fiberboard preparation process according to claim 1, characterized in that: The method for treating the sulfamic acid solution comprises: The natural plant fiber is crushed to a particle size of 1 to 3 mm to obtain crushed fiber, and then a sulfamic acid solution is added, and the fiber is allowed to stand and dried to obtain dry fiber with a water content of 5 to 7%.

3. The fiberboard preparation process according to claim 2, characterized in that: The concentration of the sulfamic acid solution is 65-75 mg / L, the amount of the sulfamic acid solution added is 40-45% of the weight of the pulverized fiber, and the standing time is 2-3 days.

4. The fiberboard preparation process according to claim 2, characterized in that: The method of the acid solution treatment comprises: Add acetic acid solution with a volume concentration of 20-25% of the dry fiber weight to the dry fiber, stir, and let stand at room temperature and pressure for 20-24 hours; wherein the volume concentration of the acetic acid solution is 3-5%.

5. The fiberboard preparation process according to claim 4, characterized in that: The alkaline solution treatment method comprises: Continue to add 40-45% of the dry fiber weight of sodium hydroxide solution to the solution treated with the acid solution, stir, let it stand for 8-10 hours, and dry it to a moisture content of 8-10% to obtain acid-base treated fiber; wherein the alkaline solution is a sodium hydroxide solution with a concentration of 32-36 mg / L.

6. The fiberboard preparation process according to claim 4, characterized in that: The method further includes placing the alkali-treated fiber in a heating kettle, adjusting the vacuum degree to -85 to -90 kPa, heating to 270 to 290° C. at a rate of 2 to 3° C. / min, maintaining the temperature for 30 to 40 minutes, adjusting the pressure to normal, maintaining the temperature for 15 to 25 minutes, and naturally cooling the temperature to 50 to 70° C. to obtain high-pressure treated fiber.

7. The fiberboard preparation process according to any one of claims 1 to 6, characterized in that: In step s200, the adhesive comprises, by weight, 5 to 10 parts of soybean protein glue, 42 to 44 parts of chlorinated polypropylene resin, 27 to 29 parts of polysiloxane resin, 21 to 23 parts of acrylic emulsion, 16 to 18 parts of polydimethylsiloxane, and 5 to 7 parts of nano zinc oxide.

8. The fiberboard preparation process according to claim 7, characterized in that: The adhesive further contains 0.5 to 1 parts by weight of additives, which include natural antibacterial agents, flame retardants and VOC adsorbents.

9. The fiberboard preparation process according to any one of claims 1 to 6, characterized in that: In step s300: the amount of the adhesive added is 16-18% of the weight of the pretreated fiber.

10. The fiberboard preparation process according to claim 1, characterized in that: In step s400: the pressure of the hot pressing curing is 60-65 MPa; wherein, the temperature is first heated to 220-240°C at a rate of 2-3°C / min, kept at this temperature for 25-35 minutes, and then slowly lowered to 170-190°C and kept at this temperature for 15-20 minutes.

Images