Method for manufacturing e0 grade low odor fiberboard from poplar and fiberboard thereof

Abstract

The present application belongs to the technical field of wood processing, and relates to a manufacturing method of E0-level poplar low-odor fiberboard, which comprises the following steps: poplar peeling, adding antibacterial and mildewproof agent, storing for 1-2 months, wood chip screening, washing, steaming, fiber separation, glue application, including adding odor removal agent, environment-friendly adhesive, waterproof agent and curing agent, drying and sorting, laying and forming, pre-pressing, hot pressing, board turning and cooling, sanding, spraying sealing agent, inspection and grading, and packaging and warehousing. The E0-level poplar low-odor fiberboard produced by the present application can eliminate the sour smell of existing poplar boards caused by microbial parasitic metabolism, reduce the peculiar smell caused by fatty acid oxidation, adsorb the odor of wood itself, and reduce the concentration of odor molecules. The added titanium dioxide is distributed in the board, and continuously eliminates peculiar smell through photocatalysis; the environmental protection quality and function of the fiberboard are improved, and the demand for high-quality life is met.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of wood processing, and relates to the manufacturing of fiber boards, in particular to a manufacturing method of E0-level poplar low-odor fiber boards and the fiber boards. BACKGROUND

[0002] China is the largest country in the world in terms of production, consumption and trade of wood materials and products, and the total annual output value of wood materials and products exceeds 3 trillion yuan. As the main wood material, man-made boards are widely used in furniture and building decoration. As one of the important sub-categories of man-made boards, fiber boards are made of wood fibers or other plant fibers as raw materials, and are prepared by fiber preparation and application of synthetic resin under the conditions of heating and pressing. With the continuous improvement of people's pursuit of a better life, consumers in the custom home industry are increasingly concerned about the odor of furniture. Some existing boards have a stimulating odor problem, and custom home manufacturers hope that board manufacturers can provide green and environmentally friendly low-odor boards for the manufacture of furniture such as wardrobes and cabinets.

[0003] The odor sources of fiber boards made of poplar mainly include the following aspects: (1) During the storage of poplar and poplar chips, due to high temperature and high humidity, the rotten odor and the odor of decay are generated, mainly under the suitable conditions of temperature and humidity, some microorganisms will parasitize and multiply, and then metabolize to produce new compounds, thereby emitting the odor of poplar; (2) During the production of poplar fiber boards, the extraction of wood extractives and the volatilization of lipids and oxygen under the action of temperature, moisture and light will generate aldehydes, ketones, acids and alcohols, thereby producing a foul odor; (3) The foreign odor generated by the additives applied during the production of the board, such as unsuitable adhesives and waterproof agents; (4) The odor of poplar itself, the odor of wood itself mainly comes from the high molecular compounds in the cells of wood, such as terpenes and other organic compounds. The odor of terpenes in fast-growing wood is a naturally released compound and has no harm to human health. SUMMARY

[0004] In order to reduce the odor of poplar fiber boards, it is necessary to eliminate the rotten odor and the odor of aldehydes, ketones and acids generated during the storage and production of poplar, and the application discloses a manufacturing method of E0-level poplar low-odor fiber boards to realize the odor reduction and control of fiber boards, obtain low-odor fiber boards, provide support for the quality improvement of boards, and further expand the application of fiber boards in indoor decoration.

[0005] TECHNICAL SCHEME

[0006] A kind of E0 grade poplar low odor fiberboard manufacturing method, comprising: poplar peeling→ chip, add antibacterial mildewproof agent→ store 1-2 months→ wood chip screening→ washing→ cooking→ fiber separation→ glue application, including the application of odor removal agent, environmentally friendly adhesive, waterproof agent, curing agent→ dry selection→ laying and forming→ pre-pressing→ hot pressing→ board cooling→ sanding→ spray sealant→ inspection grading→ packaging storage, wherein:

[0007] The chip, antibacterial mildewproof agent adding process, 0.1-1%, preferably 0.5% of antibacterial mildewproof agent is added to poplar chip relative to the mass of absolutely dry wood chip;

[0008] The cooking process, pre-cooking temperature is 85-90 DEG C, cooking temperature is 160-170 DEG C, and cooking time is 2-2.5 min;

[0009] The glue application, including the application of odor removal agent, environmentally friendly adhesive, waterproof agent, curing agent process, the addition amount of odor removal agent is 1-3 kg / m 3 , preferably 2 kg / m 3 , the application amount of environmentally friendly adhesive is 175-220 kg / m 3 , preferably 200 kg / m 3 ;The addition amount of waterproof agent is 4-8 kg / m 3 , preferably 6 kg / m 3 ;The addition amount of curing agent is 2-4 kg / m 3 , preferably 3 kg / m 3 ;Each component is applied relative to the volume of wood fiber.

[0010] The preferred disclosure of the application, the mildew-resistant antibacterial agent is the model KEPUYIN-M002 mildew-resistant antibacterial agent produced by Guangdong Kepu Yin Biotechnology Co., Ltd.;When using, dilute into solution with 5-20 times water.

[0011] The preferred disclosure of the application, the odor removal agent is applied in poplar fiber alone, or is mixed with environmentally friendly adhesive and is simultaneously applied to poplar fiber.

[0012] The preferred disclosure of the application, the main component of the odor removal agent is nanometer titanium dioxide.

[0013] Further, the odor removal agent, its preparation method includes the following steps:

[0014] A, take the plant extract, the plant extract is one or more of tea polyphenol extract, rosemary extract, liquorice extract, citric acid, wherein tea polyphenol extract 0-20 parts, rosemary extract 0-10 parts, liquorice extract 0-10 parts, citric acid 0-2 parts, each component is not 0 parts;Then take one or more of emulsifier Tween 20T-20, Span 80, fatty alcohol polyoxyethylene ether AEO-9, wherein the mass of the emulsifier is 1-3 times the mass of the plant extract, mix and stir uniformly;

[0015] B, take 1-3 times the mass of the plant extract hydroxypropyl-β-cyclodextrin dissolved in deionized water, and prepare a 5-15% concentration aqueous solution, slowly pour the hydroxypropyl-β-cyclodextrin solution along the wall into the mixture obtained in step A, and stir to make the solution system uniform;

[0016] C, adjust the pH of the system to 5.0-9.0 with sodium hydroxide solution, continue to stir, after the system is stable, add nano titanium dioxide, continue to stir, prepare a translucent to white emulsion, namely, the content of the nano titanium dioxide is 1-4 wt.% of the finished emulsion.

[0017] In the preferred disclosure of the application, in step A, the tea polyphenol extract is 10 parts, the rosemary extract is 5 parts, the liquorice extract is 5 parts, and the citric acid is 1 part.

[0018] In the preferred disclosure of the application, in step C, the concentration of the sodium hydroxide solution is 0.1 mol / L.

[0019] In the preferred disclosure of the application, in step C, the particle size of the nano titanium dioxide is 10-20 nm, and the content is 3 wt.% of the finished emulsion.

[0020] In the preferred disclosure of the application, the preparation process of the environment-friendly adhesive comprises the following steps:

[0021] (1) Add F1 to the reactor, adjust the pH to 8.5-9.0 with a lye solution, add U1, stir, and heat to 85℃ in 30-40 min by steam, and keep the temperature for 13-16 min, preferably 15 min, and control the pH at 6.5-7.5;

[0022] (2) slowly adjust the pH to 4.5-4.7 with formic acid, and react at a temperature of 88-89℃ until white mist appears in the reaction solution dropped in ice water;

[0023] (3) adjust the pH of the reaction solution to 6.0-6.5 with a lye solution, add U2, heat to 85℃, and keep the temperature for 8-12 min, preferably 10 min;

[0024] (4) Adjust the pH to 9.0-9.3 with a caustic solution, and then add F2 and M, and heat to 88-92 DEG C, and keep the system at 90 DEG C for 45 min, and during the constant temperature process, the pH is kept above 8.3;

[0025] (5) After the constant temperature process, cool rapidly by circulating cooling water, and then add U3 at 80 DEG C, and cool to 35 DEG C, and adjust the pH to 7.0-8.0, and then glue is discharged;

[0026] In the formula, the amount of melamine (M) accounts for 5-12% of the mass of the environment-friendly adhesive, the molar ratio of formaldehyde (F) to urea (U) and melamine is 0.80-0.82, formaldehyde is added twice, wherein F1 is 84% and F2 is 16%, urea is added three times, and melamine is added once, the molar ratio of F1 to U1 is 2.0-2.2, and the molar ratio of F1 to the sum of U1 and U2 is 1.4-1.6.

[0027] In the preferable disclosed embodiment of the application, the mass percentage concentration of the caustic solution used for adjusting the pH is 25%.

[0028] In the preferable disclosed embodiment of the application, the waterproof agent is No. 58 fully refined paraffin wax.

[0029] In the preferable disclosed embodiment of the application, the curing agent is a composite curing agent, the composite curing agent is a mixture of phosphoric acid and ammonium sulfate in a molar ratio of 1:1, the concentration of the aqueous solution after mixing of the two is 20-40%, and the pH value of the aqueous solution is 4-5.

[0030] In the preferable disclosed embodiment of the application, in the drying and sorting process, the inlet temperature is 160-180 DEG C, and the outlet temperature is 80-90 DEG C.

[0031] In the preferable disclosed embodiment of the application, in the hot pressing process, the hot pressing temperature is set to 170-235 DEG C, five temperature zones are adopted, the hot pressing pressure is 0-4 MPa, the hot pressing factor is 7.0-8.0 s / mm, and the highest pressure is 3 MPa.

[0032] The E0 grade poplar low-odor fiberboard manufactured by the method disclosed in the application meets the odor grade ≤2 grade in LY / T3236-2020 "Artificial board and its product odor grading and its evaluation method" in addition to all the physical and chemical performance of the ordinary fiberboard GB / T11718.

[0033] The key points of the poplar low-odor fiberboard production method disclosed in the application are the selection and application of the antibacterial and mildew-proof agent, the preparation and application of the odor removal agent, the preparation and application of the E0 grade adhesive matched with the odor removal agent, the suitable time and temperature of the wood chip cooking process, the drying process, and the suitable pressure, temperature and speed of the hot pressing process.

[0034] Poplar wood chips in the process of storage, in the appropriate temperature and humidity environment, easy to mildew and rot, microbial fermentation produce irritating odor, need to add the appropriate amount of antibacterial and mildewproof agent in the poplar chip process.

[0035] Because the content of poplar wood semi-fiber is more than that of pine wood, the water absorption thickness expansion rate of the board will be higher, and some poplar wood has higher pH. Therefore, the preparation of the environmentally friendly adhesive adopts the step of adding formaldehyde twice, so that the reaction of formaldehyde with urea and formaldehyde with triamine is more sufficient. The first formaldehyde and urea are subjected to polycondensation reaction under acidic conditions to generate sufficient methylol groups, thereby ensuring the interfacial strength of the adhesive. The second formaldehyde and melamine are subjected to reaction under alkaline conditions to generate methylol melamine, and the water resistance of this group is good, which can improve the water resistance of the glue and further improve the water resistance of the poplar board. The deodorizing agent containing titanium dioxide is added to cover the odor by photodegradation and odor application, so as to reduce the odor of the poplar board.

[0036] Beneficial effects

[0037] The E0 grade poplar low-odor fiberboard produced by the present application can eliminate the sour smell of existing poplar boards caused by microbial parasitic metabolism of raw materials, reduce the peculiar smell caused by oxidation of fatty acids, adsorb the odor of wood itself, and reduce the concentration of odor molecules. At the same time, the titanium dioxide added in the formula is distributed in the board, which continuously eliminates the peculiar smell through photocatalysis. The board can continuously have the effects of deodorization, antibacterial and mildew prevention under the action of light in the subsequent storage and use. The manufacturing method disclosed in the present application improves the environmental quality and function of the fiberboard, and meets the demand for high-quality life. DETAILED DESCRIPTION

[0038] The present application will be described in detail below with reference to examples, so that those skilled in the art can better understand the present application, but the present application is not limited to the following examples.

[0039] Examples

[0040] I. Preparation process of E0 grade poplar fiberboard with environmentally friendly glue

[0041] Dosage:

[0042] Formaldehyde: F1 = 9500 kg, F2 = 1800 kg;

[0043] Urea: U1 = 3300 kg, U2 = 1400 kg, U3 = 4350 kg;

[0044] Melamine: M = 2700 kg;

[0045] 1. Add F1, add sodium hydroxide solution (25%), adjust pH = 8.5-9.0;

[0046] 2. Add U1, start the blender, and steam to 85°C for 30-40 minutes, keep the temperature for 15 minutes, and control the pH at 6.5-7.5;

[0047] 3. Slowly add formic acid, adjust the pH to 4.5-4.7, and react at 88-89°C until white mist appears in the reaction solution dropped in ice water;

[0048] 4. Add caustic solution, adjust the pH of the reaction solution to 6.0-6.5, and add U2;

[0049] 5. Increase the temperature to 85°C, keep the temperature for 10 minutes, add caustic solution to adjust the pH to 9.0-9.3, and add M;

[0050] 6. Add F2, increase the temperature to 88-92°C, and keep the temperature at 90°C for 45 minutes; during the 45 minutes, the pH is kept above 8.3, and if the pH decreases, add caustic solution to adjust the pH;

[0051] 7. After the constant temperature ends, quickly cool with cooling water, add U3 at 80°C, cool to 35°C, adjust the pH to 7.6-8.0, and discharge the glue.

[0052] II. Preparation method of deodorant

[0053] 1. Weigh the plant extracts: tea polyphenol extract 8 parts, rosemary extract 6 parts, licorice extract 6 parts, and citric acid 1 part; weigh the emulsifiers Tween 20T-20 32 parts, fatty alcohol polyoxyethylene ether AEO-9 10 parts, and Span 80 18 parts, and add them to a container, and stir to make them uniform;

[0054] 2. Dissolve 25 parts of hydroxypropyl-β-cyclodextrin in 225 parts of deionized water to prepare an aqueous solution with a concentration of about 10%, and then slowly pour the hydroxypropyl-β-cyclodextrin solution along the wall into the mixture of step 1, and stir to make the solution system uniform;

[0055] 3. Adjust the pH to 7-8 with 0.1 mol / L sodium hydroxide solution;

[0056] 4. Stir at room temperature for 4 hours, after the system is stable, add 25 parts of nano titanium dioxide, and continue to stir at room temperature to obtain a semi-transparent to white emulsion.

[0057] III. Manufacturing method of low-odor poplar fiberboard

[0058] The poplar is sliced, and an antibacterial and mildew-proof agent is added in the slicing process, and the addition amount of the antibacterial and mildew-proof agent is 0.1-1% relative to the absolutely dry wood chips, and the mildew-proof agent is diluted with water at a ratio of 1:10;

[0059] The poplar chips are stored in a chip warehouse for 1-2 months for use, and the smell of the stored poplar chips is obviously reduced. Since the antibacterial and mildew-proof agent is added, the peculiar smell caused by microbial mold during storage is avoided;

[0060] The wood chips are screened and then washed to remove impurities such as mud. After pre-cooking at 90°C, the wood chips enter the cooking process at 165°C for 2.5 minutes.

[0061] The cooked wood chips enter the grinder for fiber separation, and 58# fully refined paraffin is added to the grinder at an amount of 6 kg / m 3 A curing agent, an environmentally friendly adhesive, and a deodorizing agent are added at the spray pipe. The curing agent is added at an amount of 2.5 kg / m 3 The environmentally friendly adhesive is applied at an amount of 200 kg / m 3 The deodorizing agent is added at an amount of 2 kg / m 3 The deodorizing agent can be applied alone or mixed with the environmentally friendly adhesive in a certain proportion before being applied together.

[0062] The glued fibers enter the fiber bin after being dried by flue gas drying. The inlet temperature of the flue gas drying is 180°C, and the outlet temperature is 80°C. The moisture content of the dried fibers is controlled at 9-12%.

[0063] The fibers in the bin are laid by a laying machine and then pre-pressed. The pre-pressed fiber board enters the press for hot pressing. The hot pressing temperature is 228, 218, 205, 196, and 180°C respectively in five hot pressing zones, and the hot pressing factor is controlled at 7.6-7.8 s / mm.

[0064] The low-odor board out of the press is cooled by a board turning machine and then stored in a separate warehouse to avoid interference with other odor boards.

[0065] After 48 hours of storage, sanding is performed, and the sanded fiber board is sorted and stored.

[0066] The 10mm E0 poplar fiber board prepared by the above steps is detected according to the standards GB / T11718-2019, LY / T3236-2020, HJ571-2010, and LY / T2230-2013, and the results are as follows:

[0067] Performance Indicators 10 mm E0 grade poplar fiberboard Density kg / m 3 ]] 845 Surface Bond Strength MPa 1.9 Panel Moisture Content % 5.8 Internal Bond Strength MPa 1.8 Modulus of Rupture MPa 52 Water Absorption Thickness Swelling % Formaldehyde Emission mg / 100g Odour Rating 5.1 1.8 Grade 4.4 Mould Resistance Rating 1 Grade TVOC mg / (m 2 • h) 72h 0.20 ​ ​

[0068] The above description is only an embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation, or direct or indirect application in other related technical fields, is also included in the patent protection scope of the present application.

Claims

1. A method of making an E0 grade low odor poplar fiberboard, comprising: The poplar is peeled, sliced, and then added with an antibacterial and mildewproof agent, and then stored for 1-2 months, and then screened, washed, cooked, separated, and then added with a deodorizing agent, an environment-friendly adhesive, a waterproof agent, and a curing agent, and then dried, shaped, pre-pressed, hot-pressed, cooled, sanded, sprayed with a sealing agent, and then inspected, graded, and packaged. In the slicing and antibacterial and mildewproof agent adding process, 0.1-1% of the antibacterial and mildewproof agent is added to the poplar slices relative to the mass of the absolutely dry wood slices. In the cooking process, the pre-cooking temperature is 85-90℃, the cooking temperature is 160-170℃, and the cooking time is 2-2.5min. The adding amount of the deodorant is 1-3 kg / m 3 , the applying amount of the environment-friendly adhesive is 175-220 kg / m 3 , the adding amount of the waterproof agent is 4-8 kg / m 3 , the adding amount of the curing agent is 2-4 kg / m 3 , each component is applied with respect to the volume of wood fiber; wherein the preparation method of the deodorant comprises the following steps: A. The plant extract, which is tea polyphenol extract, rosemary extract, liquorice extract and citric acid, is weighed, wherein the tea polyphenol extract is 0-20 parts, the rosemary extract is 0-10 parts, the liquorice extract is 0-10 parts, and the citric acid is 0-2 parts, and each component is not 0 part; one or more of the emulsifiers Tween 20 T-20, Span 80 and AEO-9 are weighed, wherein the mass of the emulsifier is 1-3 times that of the plant extract, and the mixture is uniformly stirred; B. The hydroxypropyl-beta-cyclodextrin is dissolved in deionized water to prepare a 5-15% aqueous solution, and the hydroxypropyl-beta-cyclodextrin solution is slowly poured along the wall into the mixture obtained in step A, and the solution system is uniformly stirred; C. The system pH is adjusted to 5.0-9.0 with a sodium hydroxide solution, and the system is continuously stirred until it is stable, then nano-titanium dioxide is added, and the stirring is continued, and a semi-transparent to white emulsion is prepared, which is obtained, and the content of the nano-titanium dioxide is 1-4wt.% of the finished emulsion.

2. The method of claim 1, wherein the E0 grade low odor poplar fiberboard is manufactured by the steps of: In the slicing and antibacterial and mildewproof agent adding process, 0.5% of the antibacterial and mildewproof agent is added to the poplar slices relative to the mass of the absolutely dry wood slices.

3. The method of claim 1, wherein the E0 grade low odor poplar fiberboard is manufactured by: The deodorizing agent is applied to the poplar wood fibers alone or mixed with the environment-friendly adhesive.

4. The method of claim 1, wherein the E0 grade low odor poplar fiberboard is manufactured by: The waterproof agent is No. 58 full-refined paraffin wax.

5. The method of claim 1, wherein the E0 grade low odor poplar fiberboard is manufactured by: The curing agent is a composite curing agent, which is a mixture of phosphoric acid and ammonium sulfate in a molar ratio of 1:1, and the concentration of the aqueous solution after mixing is 20-40%, and the pH of the aqueous solution is 4-5.

6. The method of making an E0 grade low odor poplar fiberboard of claim 1, wherein: The adding amount of the deodorant is 2 kg / m 3 , the applying amount of the environment-friendly adhesive is 200 kg / m 3 , the adding amount of the waterproof agent is 6 kg / m 3 , and the adding amount of the curing agent is 3 kg / m 3 .

7. The method of making an E0 grade low odor poplar fiberboard of claim 1, wherein: In step A, the tea polyphenol extract is 10 parts, the rosemary extract is 5 parts, the liquorice extract is 5 parts, and the citric acid is 1 part.

8. The method of claim 1, wherein the E0 grade low odor poplar fiberboard is manufactured by the steps of: In step C, the concentration of the sodium hydroxide solution is 0.1 mol / L.

9. The method of making an E0 grade low odor poplar fiberboard of claim 1, wherein: In step C, the particle size of the nano-titanium dioxide is 10-20 nm, and the content is 3wt.% of the finished emulsion.

10. The method of making an E0 grade low odor poplar fiberboard of claim 1, wherein: In the drying and sorting process, the inlet temperature is 160-180℃, and the outlet temperature is 80-90℃.

11. The method of making an E0 grade low odor poplar fiberboard of claim 1, wherein: In the hot pressing process, the hot pressing temperature is set to 170-235℃, and five temperature zones are adopted; the hot pressing pressure is 0-4MPa, and the hot pressing factor is 7.0-8.0s / mm.

12. The E0 grade low odor poplar fiberboard manufactured according to the method of any one of claims 1-11, characterized by: The E0 grade poplar low-odor fiberboard not only meets all the physical and chemical properties of ordinary fiberboard GB / T11718-2019, but also meets the odor grade ≤2 in LY / T3236-2020 "Artificial board and its products odor grading and evaluation method".