CN118222150A - Waterproof agent for medium-density fiberboard, preparation and application - Google Patents
Waterproof agent for medium-density fiberboard, preparation and application Download PDFInfo
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- CN118222150A CN118222150A CN202211638745.1A CN202211638745A CN118222150A CN 118222150 A CN118222150 A CN 118222150A CN 202211638745 A CN202211638745 A CN 202211638745A CN 118222150 A CN118222150 A CN 118222150A
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- density fiberboard
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- phenol
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- 239000011094 fiberboard Substances 0.000 title claims abstract description 79
- 239000003795 chemical substances by application Substances 0.000 title claims abstract description 50
- 238000002360 preparation method Methods 0.000 title claims abstract description 16
- 239000012188 paraffin wax Substances 0.000 claims abstract description 55
- 239000001993 wax Substances 0.000 claims abstract description 45
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 38
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical class [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 claims abstract description 30
- 239000004200 microcrystalline wax Substances 0.000 claims abstract description 28
- 235000019808 microcrystalline wax Nutrition 0.000 claims abstract description 28
- 229930040373 Paraformaldehyde Natural products 0.000 claims abstract description 23
- 229920002866 paraformaldehyde Polymers 0.000 claims abstract description 23
- 238000004078 waterproofing Methods 0.000 claims abstract description 20
- VKYKSIONXSXAKP-UHFFFAOYSA-N hexamethylenetetramine Chemical compound C1N(C2)CN3CN1CN2C3 VKYKSIONXSXAKP-UHFFFAOYSA-N 0.000 claims abstract description 18
- 239000002994 raw material Substances 0.000 claims abstract description 15
- 238000004519 manufacturing process Methods 0.000 claims abstract description 6
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 29
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 claims description 26
- 238000010438 heat treatment Methods 0.000 claims description 26
- 239000003921 oil Substances 0.000 claims description 25
- 235000019198 oils Nutrition 0.000 claims description 25
- -1 polyethylene Polymers 0.000 claims description 25
- 238000000034 method Methods 0.000 claims description 23
- HZAXFHJVJLSVMW-UHFFFAOYSA-N 2-Aminoethan-1-ol Chemical compound NCCO HZAXFHJVJLSVMW-UHFFFAOYSA-N 0.000 claims description 22
- 238000003756 stirring Methods 0.000 claims description 19
- 239000004698 Polyethylene Substances 0.000 claims description 17
- 229920000573 polyethylene Polymers 0.000 claims description 17
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 15
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 14
- 238000006243 chemical reaction Methods 0.000 claims description 13
- 238000001816 cooling Methods 0.000 claims description 13
- 229920001807 Urea-formaldehyde Polymers 0.000 claims description 12
- 238000007731 hot pressing Methods 0.000 claims description 12
- WRIDQFICGBMAFQ-UHFFFAOYSA-N (E)-8-Octadecenoic acid Natural products CCCCCCCCCC=CCCCCCCC(O)=O WRIDQFICGBMAFQ-UHFFFAOYSA-N 0.000 claims description 11
- LQJBNNIYVWPHFW-UHFFFAOYSA-N 20:1omega9c fatty acid Natural products CCCCCCCCCCC=CCCCCCCCC(O)=O LQJBNNIYVWPHFW-UHFFFAOYSA-N 0.000 claims description 11
- QSBYPNXLFMSGKH-UHFFFAOYSA-N 9-Heptadecensaeure Natural products CCCCCCCC=CCCCCCCCC(O)=O QSBYPNXLFMSGKH-UHFFFAOYSA-N 0.000 claims description 11
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 claims description 11
- ZQPPMHVWECSIRJ-UHFFFAOYSA-N Oleic acid Natural products CCCCCCCCC=CCCCCCCCC(O)=O ZQPPMHVWECSIRJ-UHFFFAOYSA-N 0.000 claims description 11
- 239000005642 Oleic acid Substances 0.000 claims description 11
- QXJSBBXBKPUZAA-UHFFFAOYSA-N isooleic acid Natural products CCCCCCCC=CCCCCCCCCC(O)=O QXJSBBXBKPUZAA-UHFFFAOYSA-N 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 11
- ZQPPMHVWECSIRJ-KTKRTIGZSA-N oleic acid Chemical compound CCCCCCCC\C=C/CCCCCCCC(O)=O ZQPPMHVWECSIRJ-KTKRTIGZSA-N 0.000 claims description 11
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 7
- 229920005989 resin Polymers 0.000 claims description 7
- 239000011347 resin Substances 0.000 claims description 7
- 239000008098 formaldehyde solution Substances 0.000 claims description 5
- 239000000853 adhesive Substances 0.000 claims description 3
- 230000001070 adhesive effect Effects 0.000 claims description 3
- 238000001035 drying Methods 0.000 claims description 3
- 238000012216 screening Methods 0.000 claims description 3
- 239000004209 oxidized polyethylene wax Substances 0.000 claims description 2
- 235000013873 oxidized polyethylene wax Nutrition 0.000 claims description 2
- 230000002940 repellent Effects 0.000 claims description 2
- 239000005871 repellent Substances 0.000 claims description 2
- 239000008159 sesame oil Substances 0.000 claims description 2
- 235000011803 sesame oil Nutrition 0.000 claims description 2
- 238000005303 weighing Methods 0.000 claims description 2
- 238000009966 trimming Methods 0.000 claims 1
- 238000010521 absorption reaction Methods 0.000 abstract description 33
- 239000002023 wood Substances 0.000 abstract description 10
- 239000000463 material Substances 0.000 abstract description 6
- 239000000047 product Substances 0.000 description 21
- 229920002522 Wood fibre Polymers 0.000 description 16
- 230000000052 comparative effect Effects 0.000 description 16
- 239000002025 wood fiber Substances 0.000 description 16
- 239000000835 fiber Substances 0.000 description 13
- GZCGUPFRVQAUEE-SLPGGIOYSA-N aldehydo-D-glucose Chemical compound OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C=O GZCGUPFRVQAUEE-SLPGGIOYSA-N 0.000 description 9
- 229920000877 Melamine resin Polymers 0.000 description 7
- 238000012545 processing Methods 0.000 description 7
- 238000002844 melting Methods 0.000 description 5
- 230000008018 melting Effects 0.000 description 5
- 235000011121 sodium hydroxide Nutrition 0.000 description 4
- 239000000839 emulsion Substances 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- 239000002861 polymer material Substances 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 230000001105 regulatory effect Effects 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 239000004094 surface-active agent Substances 0.000 description 2
- 241000219000 Populus Species 0.000 description 1
- 238000004026 adhesive bonding Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 239000012948 isocyanate Substances 0.000 description 1
- 150000002513 isocyanates Chemical class 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 229920001568 phenolic resin Polymers 0.000 description 1
- 239000011120 plywood Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27N—MANUFACTURE BY DRY PROCESSES OF ARTICLES, WITH OR WITHOUT ORGANIC BINDING AGENTS, MADE FROM PARTICLES OR FIBRES CONSISTING OF WOOD OR OTHER LIGNOCELLULOSIC OR LIKE ORGANIC MATERIAL
- B27N3/00—Manufacture of substantially flat articles, e.g. boards, from particles or fibres
- B27N3/04—Manufacture of substantially flat articles, e.g. boards, from particles or fibres from fibres
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27N—MANUFACTURE BY DRY PROCESSES OF ARTICLES, WITH OR WITHOUT ORGANIC BINDING AGENTS, MADE FROM PARTICLES OR FIBRES CONSISTING OF WOOD OR OTHER LIGNOCELLULOSIC OR LIKE ORGANIC MATERIAL
- B27N3/00—Manufacture of substantially flat articles, e.g. boards, from particles or fibres
- B27N3/002—Manufacture of substantially flat articles, e.g. boards, from particles or fibres characterised by the type of binder
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27N—MANUFACTURE BY DRY PROCESSES OF ARTICLES, WITH OR WITHOUT ORGANIC BINDING AGENTS, MADE FROM PARTICLES OR FIBRES CONSISTING OF WOOD OR OTHER LIGNOCELLULOSIC OR LIKE ORGANIC MATERIAL
- B27N3/00—Manufacture of substantially flat articles, e.g. boards, from particles or fibres
- B27N3/08—Moulding or pressing
- B27N3/10—Moulding of mats
- B27N3/12—Moulding of mats from fibres
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D161/00—Coating compositions based on condensation polymers of aldehydes or ketones; Coating compositions based on derivatives of such polymers
- C09D161/04—Condensation polymers of aldehydes or ketones with phenols only
- C09D161/06—Condensation polymers of aldehydes or ketones with phenols only of aldehydes with phenols
- C09D161/14—Modified phenol-aldehyde condensates
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
- C09D7/40—Additives
- C09D7/60—Additives non-macromolecular
- C09D7/63—Additives non-macromolecular organic
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
- C09D7/40—Additives
- C09D7/65—Additives macromolecular
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
- C08L2205/025—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Forests & Forestry (AREA)
- Dry Formation Of Fiberboard And The Like (AREA)
Abstract
The invention discloses a waterproofing agent for medium density fiberboard, and preparation and application thereof. The waterproof agent for the medium-density fiberboard is prepared from the following raw materials in parts by mass: 100 parts of modified phenolic resin, 1-200 parts of white oil, 10-1000 parts of paraffin wax, 1-100 parts of microcrystalline wax, 1-100 parts of synthetic wax and 0.1-5 parts of urotropine and/or paraformaldehyde. The medium density fiberboard prepared by the waterproof agent for the medium density fiberboard has the water absorption thickness expansion rate of less than or equal to 7% in 24 hours, the internal bonding strength is improved by more than 60%, and the waterproof agent can be widely applied to the production of high-humidity environment reinforced wood floor base materials, medium density fiberboard and high density fiberboard.
Description
Technical Field
The invention belongs to the technical field of artificial board production. More particularly, relates to a waterproofing agent for medium density fiberboard, and preparation and application thereof.
Background
The dry shrinkage and wet expansion of wood materials such as wood, fiber boards, shaving boards, plywood, wood floors and the like and products thereof are main technical problems affecting the use of the wood materials. Dimensional stability is one of the main technical indexes for evaluating wood materials and products.
In order to reduce the water absorption thickness expansion rate of the medium density fiberboard and improve the dimensional stability of the medium density fiberboard, the traditional production process is to spray 58# paraffin or 62# paraffin into a slurry pipe after melting, adhere the wet fiber mixed paraffin to the surface of the fiber and delay the penetration of water into the medium density fiberboard by means of the hydrophobicity of the paraffin. The addition of paraffin is usually 0.5-1.5% of the dry fiber mass percent, and the addition of excessive paraffin can affect the bonding between fibers and reduce the mechanical properties of the medium density fiberboard. The medium density fiberboard or the high density fiberboard produced by adopting urea formaldehyde resin or melamine modified urea formaldehyde resin has the limit water absorption thickness expansion rate of about 7 percent in 24 hours.
The paraffin is prepared into a waterproof agent emulsion by adopting a surfactant, and the paraffin emulsion or suspension with the wavelength of 200 nm-30 mu m is prepared, so that the coverage rate of the paraffin on the surface of the fiber is improved, and the dosage of the paraffin waterproof agent is reduced. But the surfactant obviously reduces the surface tension of water, improves the wettability of the wood material, increases the water absorption speed and water absorption capacity of the medium density fiberboard, and has higher expansion rate of ultimate water absorption thickness after 24 hours than that of molten paraffin.
Whether molten paraffin or paraffin emulsion is used as the waterproofing agent of the medium density fiberboard, the water-proof performance of the medium density fiberboard is rapidly deteriorated after the secondary processing hot pressing, and the water absorption thickness expansion rate is increased by 50-200% in 24 hours. Researches show that under the combined action of temperature, pressure and moisture in the medium density fiberboard during secondary processing, paraffin partially covered on the surface of the fiber is melted again and even vaporized, and enters the fiber, so that the paraffin is one of the main reasons for the deterioration of the waterproof performance of the medium density fiberboard.
Therefore, there is a need to develop a novel waterproofing agent for medium density fiberboard to overcome the problems existing in the prior art.
Disclosure of Invention
In order to solve the above problems, a first object of the present invention is to provide a waterproofing agent for medium density fiberboard.
A second object of the present invention is to provide a method for producing a water repellent for medium density fiberboard as described above.
The third object of the invention is to provide an application of the waterproofing agent for the medium density fiberboard in the preparation of the artificial board.
In order to achieve the first object, the present invention adopts the following technical scheme:
The invention discloses a waterproof agent for a medium-density fiberboard, which is characterized by being prepared from the following raw materials in parts by mass: 100 parts of modified phenolic resin, 1-200 parts of white oil, 10-1000 parts of paraffin wax, 1-100 parts of microcrystalline wax, 1-100 parts of synthetic wax and 0.1-5 parts of urotropine and/or paraformaldehyde.
In order to solve the technical bottleneck that the water absorption thickness expansion rate of the medium density fiberboard produced by adopting urea formaldehyde resin or melamine modified urea formaldehyde resin is high, the waterproof performance is further deteriorated in secondary processing, the modified phenolic resin is used as a carrier, and white oil, microcrystalline wax and synthetic wax components are added into 52# to 62# paraffin, which is a common waterproof agent for the medium density fiberboard, so that the waterproof agent for the medium density fiberboard is prepared. In the hot press molding process of the fiber board, the modified phenolic resin in the waterproof agent reacts with urotropine and/or paraformaldehyde, urea-formaldehyde resin coated on the fiber and free formaldehyde thereof to generate a net-shaped polymer material with toughness, and the net-shaped polymer material covers the surface of the fiber, thereby playing a double function of gluing the fiber and preventing water, and improving the strength and waterproof performance of the artificial board; meanwhile, the reticular polymer material formed by the modified phenolic resin, high-melting-point microcrystalline wax and synthetic wax form a ductile protective film, so that the quantity of paraffin entering into wood cell cavities and pores during hot press molding of the medium-density fiberboard and secondary hot press processing of the medium-density fiberboard is reduced, and the waterproof effect of the waterproof agent is improved; oleic acid, ethanolamine and dimethylacetamide in the modified phenolic resin disperse and emulsify paraffin, microcrystalline wax and synthetic wax, reduce the particle size of the paraffin, microcrystalline wax and synthetic wax, and effectively improve the uniformity of the distribution of the paraffin, microcrystalline wax and synthetic wax on the fiber. The white oil has low viscosity and good permeability, can enter into the cell cavities and pores of the wood, and covers the surfaces of the cell cavities and the pores when the medium-density fiberboard is subjected to hot press molding and secondary processing hot press, thereby improving the waterproof performance of the wood material.
Further, the waterproof agent for the medium-density fiberboard is prepared from the following raw materials in parts by mass: 100 parts of modified phenolic resin, 5-50 parts of white oil, 20-500 parts of paraffin wax, 5-50 parts of microcrystalline wax, 5-50 parts of synthetic wax and 0.3-3.0 parts of urotropine and/or paraformaldehyde.
Further, the modified phenolic resin is prepared according to the following process:
(1) Adding a certain amount of phenol into a reaction kettle, heating to 50-60 ℃, adding phosphoric acid, and keeping for 10-15 minutes;
(2) Adding formaldehyde solution, heating to 98-100 ℃, and keeping for 60-120 minutes;
(3) Cooling to 75-80deg.C, and adjusting pH to 8.5-9.5 with sodium hydroxide;
(4) Slowly adding paraformaldehyde, and maintaining at 90-95deg.C for 30-120 min;
(5) Detecting the viscosity of the resin, adding oleic acid, ethanolamine and dimethylacetamide when the viscosity is 50-2000cps, and cooling to obtain the final product.
Further, in the step 1, the molar ratio of phosphoric acid to phenol is 0.02-0.04:1; in the step 2, the molar ratio of formaldehyde to phenol is 0.65-0.85:1; in the step 4, the molar ratio of the paraformaldehyde to the phenol is 0.80-1.2:1, so that the molar ratio of (formaldehyde+paraformaldehyde)/phenol is 1.60-2.10.
Further, in the step 5, the mass ratio of oleic acid to phenol is 0.1-1:1, the mass ratio of ethanolamine to phenol is 0.02-0.1:1, and the mass ratio of dimethylacetamide to phenol is 0.005-0.05:1.
Further, the white oil types include, but are not limited to, one or more of 5#, 7#, 10#, 15#, 22#, 26#, 32#, 46#, 86#, 100#, 220#, 320 #; preferably, white oil is selected from one or more of 10#, 15#, 22#, 26#, 32 #.
Further, the paraffin wax includes one or more of the following types including, but not limited to, 50#, 52#, 54#, 58#, 60#, 62#, 64#, 68#, and 70 #; preferably, the paraffin wax of one or more of 56#, 58#, 60#, 62# is selected to be better.
Further, the model of the microcrystalline wax includes, but is not limited to, one or more of 70#, 75#, 80#, 85#, 90 #; preferably, a soft, high viscosity microcrystalline wax is selected for better results.
Further, the synthetic waxes include, but are not limited to, one or more of polyethylene wax, oxidized polyethylene wax, fischer-tropsch wax, hydrogenated cage sesame oil wax, S wax, OP wax, O wax, E wax; preferably, the synthetic wax is polyethylene wax with better effect.
In order to achieve the second object, the present invention adopts the following technical scheme:
the invention discloses a method for preparing a waterproof agent for a medium-density fiberboard, which comprises the following steps:
weighing the self-made modified phenolic resin according to the method, heating to 50-90 ℃, adding white oil, stirring for 15-20 minutes at the speed of 60-2000 rn/min to obtain a first mixture, and then heating to 90-120 ℃; adding paraffin wax, microcrystalline wax and synthetic wax into the first mixture, stirring and completely dissolving, and stirring for 15-20 minutes at the speed of 60-2000 rn/min to obtain a second mixture; adding urotropine and/or paraformaldehyde into the second mixture, and stirring at the rotating speed of 60-2000 rn/min for 30-120 min to obtain the product.
In order to achieve the third object, the present invention adopts the following technical scheme:
the invention discloses an application of a waterproof agent for preparing a medium-density fiberboard.
Further, the specific steps for preparing the medium density fiberboard are as follows:
adding urea-formaldehyde resin adhesive and a waterproofing agent for the medium-density fiberboard into a spraying pipe, rapidly drying, screening, separating, paving and prepressing to obtain a board blank, hot-pressing the board blank, and performing edge cutting, board cooling, thickness fixing and fine sanding after pressing to obtain the medium-density fiberboard.
Further, the hot pressing temperature is 170-240 ℃, the hot pressing time is 10-15 seconds/mm, and the highest unit pressure is 3.0MPa.
The beneficial effects of the invention are as follows:
1. The water-proofing agent for the medium-density fiberboard, which is produced by adopting urea formaldehyde resin or melamine modified urea formaldehyde resin, has the water absorption thickness expansion rate of less than or equal to 7% in 24 hours, and is lower than the limit value that the water absorption thickness expansion rate of more than or equal to 7% in 24 hours of the medium-density fiberboard produced by adopting 58# or 62# paraffin water-proofing agent in the prior art.
2. The water-proofing agent for the medium-density fiberboard is used, the medium-density fiberboard produced by adopting urea formaldehyde resin or melamine modified urea formaldehyde resin has the water absorption thickness expansion rate of less than or equal to 12 percent in 72 hours, and the thickness of the medium-density fiberboard product is basically stable along with the extension of the impregnation time; in the prior art, the medium density fiberboard produced by adopting a 58# or 62# paraffin waterproof agent has the water absorption thickness expansion rate of more than or equal to 20% in 72 hours, and the thickness is continuously increased along with the extension of the soaking time until the product is destroyed.
3. The water-proofing agent for the medium-density fiberboard adopts urea resin or melamine modified urea resin to produce the medium-density fiberboard, and the water absorption thickness expansion rate after secondary processing and hot pressing is less than or equal to 7 percent; the expansion rate of the water absorption thickness of the medium density fiberboard produced by the prior art after the secondary processing and hot pressing is more than or equal to 10 percent, which is close to the limit of national standard.
4. The inner bonding strength of the medium-density fiberboard produced by adopting urea-formaldehyde resin or melamine modified urea-formaldehyde resin is improved by more than 60 percent, and the inner bonding strength is improved along with the increase of the dosage of the waterproof agent; when the mass percentage of paraffin/absolute fiber is more than 1.5%, the internal bonding strength of the medium density fiberboard produced by the waterproof agent in the prior art is obviously reduced along with the increase of the dosage of the paraffin.
5. The water-proofing agent for the medium-density fiberboard, which is produced by adopting urea formaldehyde resin or melamine modified urea formaldehyde resin, can be used for producing the medium-density fiberboard used in a high-humidity environment; the prior art is directed to the production of medium density fiberboard in a highly humid environment, typically using isocyanate resins.
Detailed Description
In order to more clearly illustrate the present invention, the present invention will be further described with reference to preferred embodiments. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and that this invention is not limited to the details given herein.
In the present invention, the self-made modified phenolic resins of examples 1-3 and comparative examples 5-7 were prepared according to the following procedure:
(1) Adding 1.0 mol of phenol into a reaction kettle, starting a stirring device, heating to 50-60 ℃, adding 0.03 mol of phosphoric acid with the mass percent of 85%, and keeping for 10-15 minutes;
(2) Adding formaldehyde solution with the mass percentage of 0.68 percent of 37.0 percent, heating to 98-100 ℃ and keeping for 120 minutes;
(3) Cooling to 78-80 deg.c and regulating pH value with caustic soda to 8.5-9.0;
(4) Slowly adding paraformaldehyde to make the molar ratio of (formaldehyde + paraformaldehyde)/phenol be 1.68, and making them retain reaction at 90-93 deg.C;
(5) Detecting the viscosity of the resin, when the viscosity is 150cps, adding oleic acid, ethanolamine and dimethylacetamide, wherein the addition amounts of the oleic acid, the ethanolamine and the dimethylacetamide are respectively 21.3 percent, 3.2 percent and 2.1 percent of the addition amount of phenol, maintaining for 30 minutes, and cooling to below 50 ℃ for standby.
The self-made modified phenolic resin in examples 4-6 was prepared according to the following procedure:
(1) Adding 1.0 mol of phenol into a reaction kettle, starting a stirring device, heating to 50-60 ℃, adding 0.03 mol of phosphoric acid with the mass percent of 85%, and keeping for 10-15 minutes;
(2) Adding formaldehyde solution with the mass percentage of 1 mol percent of 37.0%, heating to 98-100 ℃, and keeping for 120 minutes;
(3) Cooling to 78-80 deg.c and regulating pH value with caustic soda to 8.5-9.0;
(4) Slowly adding paraformaldehyde to make the molar ratio of (formaldehyde + paraformaldehyde)/phenol be 1.80, and making them retain reaction at 90-93 deg.C;
(5) Detecting the viscosity of the resin, when the viscosity is 300cps, adding oleic acid, ethanolamine and dimethylacetamide, wherein the addition amounts of the oleic acid, the ethanolamine and the dimethylacetamide are 19.4 percent, 3.4 percent and 1.4 percent of the addition amount of phenol respectively, keeping for 30 minutes, and cooling to below 50 ℃ for standby.
The self-made modified phenolic resin in examples 7-9 was prepared according to the following procedure:
(1) Adding 1.0 mol of phenol into a reaction kettle, starting a stirring device, heating to 50-60 ℃, adding 0.03 mol of phosphoric acid with the mass percent of 85%, and keeping for 10-15 minutes;
(2) Adding formaldehyde solution with the mass percentage of 0.86 to 37.0 percent, heating to 98 to 100 ℃ and keeping for 120 minutes;
(3) Cooling to 78-80 deg.c and regulating pH value with caustic soda to 8.5-9.0;
(4) Slowly adding paraformaldehyde to make the molar ratio of (formaldehyde + paraformaldehyde)/phenol be 2.03, and making them retain reaction at 90-93 deg.C;
(5) Detecting the viscosity of the resin, when the viscosity is 350cps, adding oleic acid, ethanolamine and dimethylacetamide, wherein the addition amounts of the oleic acid, the ethanolamine and the dimethylacetamide are 29.5 percent, 8.5 percent and 3 percent of the addition amount of phenol respectively, keeping for 30 minutes, and cooling to below 50 ℃ for standby.
Example 1
The embodiment relates to a waterproof agent for medium density fiberboard, which comprises the following raw materials:
100 parts of self-made modified phenolic resin, 5 parts of 15# white oil, 500 parts of 58# paraffin wax, 50 parts of 85# microcrystalline wax, 50 parts of polyethylene wax and 2 parts of urotropine.
The preparation method comprises the following steps:
1) Adding 100 parts by mass of modified phenolic resin into a reaction kettle with a heating sleeve and a stirring device, and heating to 80 ℃;
2) Starting a stirrer, wherein the rotating speed is 120rn/min, adding 5 parts by mass of 15# white oil, and stirring for 15 minutes to obtain a first mixture;
3) Heating to 120 ℃, adding 500 parts by mass of 58# paraffin, 50 parts by mass of 85# microcrystalline wax and 50 parts by mass of polyethylene wax, stirring to dissolve completely, and keeping for 20 minutes to obtain a second mixture;
4) Adding 2 parts by mass of urotropine, and keeping for 60 minutes to obtain the waterproof agent for the medium-density fiberboard.
Adding urea-formaldehyde resin adhesive and the waterproof agent into poplar fibers in a guniting pipe, rapidly drying, screening, separating, paving and prepressing to obtain a plate blank, hot-pressing the plate blank, and performing edge cutting, plate cooling, thickness fixing and fine sanding after pressing to obtain the medium-density fiberboard. The hot pressing temperature of the medium density fiberboard with the thickness of 18mm is 220 ℃, the hot pressing time is 300 seconds, and the highest unit pressure is 3.0MPa. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the internal bonding strength water absorption thickness expansion rate of the product is shown in 2.
Example 2
The embodiment relates to a waterproof agent for medium density fiberboard, which comprises the following raw materials:
100 parts of self-made modified phenolic resin, 5 parts of 15# white oil, 485 parts of 58# paraffin wax, 5 parts of 85# microcrystalline wax, 5 parts of polyethylene wax and 2 parts of urotropine.
The preparation method is the same as in example 1.
Other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Example 3
The embodiment relates to a waterproof agent for medium density fiberboard, which comprises the following raw materials:
100 parts of self-made modified phenolic resin, 20 parts of 15# white oil, 360 parts of 58# paraffin wax, 10 parts of 85# microcrystalline wax, 10 parts of polyethylene wax and 1 part of urotropine.
The preparation method is the same as in example 1.
Other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Example 4
The embodiment relates to a waterproof agent for medium density fiberboard, which comprises the following raw materials:
100 parts of self-made modified phenolic resin, 50 parts of 20# white oil, 210 parts of 60# paraffin wax, 20 parts of 85# microcrystalline wax, 20 parts of polyethylene wax and 1 part of urotropine.
The preparation method is the same as in example 1.
Other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Example 5
The embodiment relates to a waterproof agent for medium density fiberboard, which comprises the following raw materials:
100 parts of self-made modified phenolic resin, 15 parts of 20# white oil, 170 parts of 62# paraffin wax, 10 parts of 80# microcrystalline wax, 5 parts of polyethylene wax and 1 part of urotropine.
The preparation method is the same as in example 1.
Other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Example 6
The embodiment relates to a waterproof agent for medium density fiberboard, which comprises the following raw materials:
100 parts of self-made modified phenolic resin, 10 parts of 15# white oil, 80 parts of 58# paraffin wax, 5 parts of 85# microcrystalline wax, 5 parts of polyethylene wax and 2.0 parts of urotropine.
The preparation method is the same as in example 1.
Other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Example 7
The embodiment relates to a waterproof agent for medium density fiberboard, which comprises the following raw materials:
100 parts of self-made modified phenolic resin, 5 parts of 15# white oil, 45 parts of 58# paraffin wax, 20 parts of 85# microcrystalline wax, 5 parts of polyethylene wax and 1.0 part of paraformaldehyde.
The preparation method is the same as in example 1.
Other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Example 8
The embodiment relates to a waterproof agent for medium density fiberboard, which comprises the following raw materials:
100 parts of self-made modified phenolic resin, 5 parts of 15# white oil, 40 parts of 58# paraffin wax, 5 parts of 85# microcrystalline wax, 5 parts of polyethylene wax and 1.5 parts of paraformaldehyde.
The preparation method is the same as in example 1.
Other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Example 9
The embodiment relates to a waterproof agent for medium density fiberboard, which comprises the following raw materials:
100 parts of self-made modified phenolic resin, 5 parts of 15# white oil, 20 parts of 58# paraffin wax, 5 parts of 85# microcrystalline wax, 5 parts of polyethylene wax and 0.5 part of paraformaldehyde.
The preparation method is the same as in example 1.
Other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Comparative example 1
Adding 100 parts by mass of 58# paraffin into a reaction kettle with a heating sleeve and a stirring device, heating to 90 ℃, and completely melting the paraffin for later use;
other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Comparative example 2
Adding 100 parts by mass of 58# paraffin and 50 parts by mass of 15# white oil into a reaction kettle with a heating sleeve and a stirring device, heating to 90 ℃, and completely melting the paraffin for later use;
other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Comparative example 3
Adding 100 parts by mass of 58# paraffin wax and 50 parts by mass of 85# microcrystalline wax into a reaction kettle with a heating sleeve and a stirring device, heating to 95 ℃, and completely melting the paraffin wax for later use;
other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Comparative example 4
Adding 100 parts by mass of 58# paraffin and 50 parts by mass of polyethylene wax into a reaction kettle with a heating sleeve and a stirring device, heating to 95 ℃, and completely melting the paraffin for later use;
other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Comparative example 5
100 Parts of self-made modified phenolic resin and 1 part of urotropine, heating to 95 ℃, and uniformly stirring for standby;
other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Comparative example 6
The modified phenolic resin was prepared as in example 1.
100 Parts of self-made modified phenolic resin, 50 parts of 15# white oil, 1100 parts of 58# paraffin wax, 20 parts of 85# microcrystalline wax, 20 parts of polyethylene wax and 2 parts of urotropine.
Other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Comparative example 7
The modified phenolic resin was prepared as in example 1.
100 Parts of self-made modified phenolic resin, 200 parts of 15# white oil, 600 parts of 58# paraffin wax, 20 parts of 85# microcrystalline wax, 20 parts of polyethylene wax and 2 parts of urotropine.
Other process conditions were the same as in example 1. Based on 100 parts by mass of absolute dry wood fiber, specific components are shown in table 1, and the water absorption thickness expansion rate of the product is shown as 2.
Table 1 raw material composition of examples and comparative examples
Table 2 shows the water absorption thickness expansion ratio of the bonding strength in the density fiberboard
| Internal bond strength | 24H Water absorption thickness expansion Rate (%) | Thickness expansion rate of water absorption for 72h (%) | |
| Example 1 | 1.07 | 6.5 | 11.3 |
| Example 2 | 1.04 | 6.4 | 11.7 |
| Example 3 | 1.05 | 6.8 | 11.5 |
| Example 4 | 1.11 | 6.7 | 11.8 |
| Example 5 | 1.08 | 5.5 | 10.8 |
| Example 6 | 1.21 | 6.1 | 10.8 |
| Example 7 | 1.23 | 5.6 | 9.9 |
| Example 8 | 1.19 | 5.9 | 10.2 |
| Example 9 | 1.27 | 5.7 | 9.8 |
| Comparative example 1 | 0.87 | 8.7 | 25.9 |
| Comparative example 2 | 0.92 | 9.8 | 27.5 |
| Comparative example 3 | 0.79 | 8.2 | 24.3 |
| Comparative example 4 | 0.91 | 8.6 | 23.9 |
| Comparative example 5 | 1.35 | 7.3 | 14.9 |
| Comparative example 6 | 0.57 | 9.2 | 21.3 |
| Comparative example 7 | 0.61 | 10.7 | 23.2 |
It should be understood that the foregoing examples of the present invention are provided merely for clearly illustrating the present invention and are not intended to limit the embodiments of the present invention, and that various other changes and modifications may be made therein by one skilled in the art without departing from the spirit and scope of the present invention as defined by the appended claims.
Claims (10)
1. The waterproof agent for the medium-density fiberboard is characterized by being prepared from the following raw materials in parts by mass: 100 parts of modified phenolic resin, 1-200 parts of white oil, 10-1000 parts of paraffin wax, 1-100 parts of microcrystalline wax, 1-100 parts of synthetic wax and 0.1-5 parts of urotropine and/or paraformaldehyde.
2. The waterproofing agent for medium density fiberboard according to claim 1, which is prepared from the following raw materials in parts by mass: 100 parts of modified phenolic resin, 5-50 parts of white oil, 20-500 parts of paraffin wax, 5-50 parts of microcrystalline wax, 5-50 parts of synthetic wax and 0.3-3.0 parts of urotropine and/or paraformaldehyde.
3. The waterproofing agent for medium density fiberboard according to claim 1, wherein the modified phenolic resin is prepared according to the following process:
(1) Adding a certain amount of phenol into a reaction kettle, heating to 50-60 ℃, adding phosphoric acid, and keeping for 10-15 minutes;
(2) Adding formaldehyde solution, heating to 98-100 ℃, and keeping for 60-120 minutes;
(3) Cooling to 75-80deg.C, and adjusting pH to 8.5-9.5 with sodium hydroxide;
(4) Slowly adding paraformaldehyde, and maintaining at 90-95deg.C for 30-120 min;
(5) Detecting the viscosity of the resin, adding oleic acid, ethanolamine and dimethylacetamide when the viscosity is 50-2000cps, and cooling to obtain the resin;
Preferably, in step 1, the molar ratio of phosphoric acid to phenol is 0.02-0.04:1; in the step 2, the molar ratio of formaldehyde to phenol is 0.65-0.85:1; in the step 4, the molar ratio of the paraformaldehyde to the phenol is 0.80-1.2:1, so that the molar ratio of (formaldehyde+paraformaldehyde)/phenol is 1.60-2.10;
preferably, in step 5, the mass ratio of oleic acid to phenol is 0.1-1:1, the mass ratio of ethanolamine to phenol is 0.02-0.1:1, and the mass ratio of dimethylacetamide to phenol is 0.005-0.05:1.
4. The waterproofing agent for medium density fiberboard according to claim 1, wherein the type of the white oil comprises one or more of 5#, 7#, 10#, 15#, 22#, 26#, 32#, 46#, 86#, 100#, 220#, 320 #;
Preferably, the model of the white oil comprises one or more of 10#, 15#, 22#, 26#, 32#.
5. The waterproofing agent for medium density fiberboard according to claim 1, wherein the paraffin wax is one or more of 50#, 52#, 54#, 58#, 60#, 62#, 64#, 68#, 70 #;
Preferably, the paraffin wax comprises one or more of 56#, 58#, 60#, 62 #.
6. The waterproofing agent for medium density fiberboard according to claim 1, wherein the model of the microcrystalline wax comprises one or more of # 70, # 75, # 80, # 85, and # 90.
7. The waterproofing agent for medium density fiberboard according to claim 1, wherein the synthetic wax comprises one or more of polyethylene wax, oxidized polyethylene wax, fischer-tropsch wax, hydrogenated cage sesame oil wax, S wax, OP wax, O wax, E wax;
Preferably, the synthetic wax is selected from polyethylene waxes.
8. The method for producing a water repellent for medium density fiberboard according to any one of claims 1 to 7, comprising the steps of:
Weighing modified phenolic resin, heating to 50-90 ℃, adding white oil, stirring for 15-20 minutes at the speed of 60-2000 rn/min to obtain a first mixture, and then heating to 90-120 ℃; adding paraffin wax, microcrystalline wax and synthetic wax into the first mixture, stirring and completely dissolving, and stirring for 15-20 minutes at the speed of 60-2000 rn/min to obtain a second mixture; adding urotropine and/or paraformaldehyde into the second mixture, and stirring at the rotating speed of 60-2000 rn/min for 30-120 min to obtain the product.
9. Use of the waterproofing agent for medium density fiberboard according to any one of claims 1 to 7 in the preparation of medium density fiberboard.
10. The use according to claim 9, characterized in that the specific steps for the preparation of medium density fiberboard are:
Adding urea resin adhesive and waterproofing agent for medium density fiberboard into a guniting pipe, rapidly drying, screening, separating, paving and prepressing to obtain a board blank, hot-pressing the board blank, and trimming, cooling, fixing thickness and finely sanding to obtain the medium density fiberboard;
preferably, the hot pressing temperature is 170-240 ℃, the hot pressing time is 10-15 seconds/mm, and the highest unit pressure is 3.0MPa.
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