Fire-retardant fireproof wooden door and preparation method thereof

Abstract

This invention belongs to the field of fire-resistant wooden doors, specifically relating to a flame-retardant fire-resistant wooden door and its preparation method. The preparation steps are as follows: step (a) preparation of the fire-resistant door core board; step (b) preparation of the decorative solid wood veneer; step (c) combination of the door core board and the decorative solid wood veneer to form a flame-retardant fire-resistant wooden door; step (d) inspection and packaging. This invention optimizes and improves the structure of ordinary solid wood composite doors, and correspondingly adjusts the composition of the door core board. By adding modified lignin to the door core, it effectively protects the wooden door from further combustion, reduces the heat release rate, and improves the physical and chemical properties and fire resistance limit of the finished flame-retardant fire-resistant wooden door.

Description

Technical Field

[0001] This invention belongs to the field of fireproof wooden doors, specifically relating to a flame-retardant fireproof wooden door and its preparation method. Background Technology

[0002] Wooden doors are closely related to people's production and daily life, and door culture holds an important place in the history of traditional Chinese architecture. Since 2010, my country has gradually formed six major wooden door production bases in the Pearl River Delta, Yangtze River Delta, Northeast China, Bohai Rim region, Southwest China, and Northwest China, making it the world's largest wooden door production base, export base, and consumer market. Currently, the main types of wooden doors on the market are solid wood doors, composite wood doors, and hollow wood doors. After more than 20 years of development, my country's wooden door industry has gradually entered a stage of steady development.

[0003] Patent CN 106246078 A discloses a high-strength fireproof wooden door, which consists of a door edge, a fireproof door core panel, and a decorative surface. The production method is as follows: (1) Prepare the door core board: Prepare the raw materials according to the following weight parts: 10 parts of lightly calcined magnesium oxide powder, 2-2.5 parts of magnesium sulfate, 0.05 parts of chitosan, 0.05 parts of magnesium aluminum spinel, 0.6 parts of pine wood chips, 1-1.5 parts of sodium octenyl succinate starch, 0.8 parts of phosphate starch, 0.1-0.2 parts of tourmaline powder, 0.8-1 parts of andalusite powder, 0.8 parts of organosilicon waterproofing agent powder, 0.08 parts of nano silica, 0.1 parts of polypropylene fiber, 8-10 parts of water and 2-3 parts of foam; then dissolve magnesium sulfate to make magnesium sulfate solution; add the other raw materials except foam to the magnesium sulfate solution in proportion and stir evenly, then add foam and mix evenly to obtain slurry; after pretreatment, curing and maintenance of the slurry, fireproof door core board is obtained; (2) Combine the door edge, door core board decorative surface and door core board together to obtain a wooden door. While possessing good fire resistance and a certain degree of mechanical strength, wooden doors are prone to deformation or damage upon impact. The core filling material is often lightweight, consisting of wood chips, scraps, and other offcuts, resulting in poor sound insulation and fire resistance, making them susceptible to fire spread and failing to meet practical needs. Therefore, improving the physical and chemical properties of wooden doors, especially their fire resistance and heat insulation performance, remains a topic worthy of further exploration. Summary of the Invention

[0004] In view of the problems existing in the background technology, the present invention optimizes and improves the structure of ordinary solid wood composite doors, and adjusts the composition of the door core board accordingly, thereby improving the physical and chemical properties and fire resistance limit of the finished flame-retardant and fireproof wooden doors.

[0005] A method for preparing a flame-retardant and fireproof wooden door includes the following steps:

[0006] Step (a) Preparation of fireproof door core board: Weigh the required raw materials and glycerol according to the proportions, mix them evenly, heat to 90°C under stirring, react for 2 hours to obtain slurry, inject the slurry into the mold for curing, remove the mold after 3-4 hours, and cure under certain conditions to obtain fireproof door core board;

[0007] Step (b) Preparation of decorative solid wood door veneer: Select wood without internal cracks, knots, rotten wood, or blue stain. After drying the wood, perform rough planing and cut the wood to the required size to obtain the door panel. Then, vacuum pressurize the door panel to inject flame retardant, polish it, wipe the dust off the surface, and spray paint and color-correct one side of the door panel.

[0008] Step (c) The door core panel and the decorative solid wood door skin are combined to form a flame-retardant and fireproof wooden door: After applying two-component epoxy resin glue to the two decorative door panels respectively, they are attached to both sides of the door core panel and sealed with solid wood strips. After high temperature and hot pressing, the door body is made and the excess glue is sanded off.

[0009] Step (d) Check the packaging: Check whether the overall color matching of the flame-retardant and fireproof wooden door is harmonious and consistent, check whether the surface of the door panel is smooth, repair any defects, wipe the dust off the surface of the wooden door, pack it and put it into the warehouse for storage.

[0010] The raw material composition includes: 30-35 parts modified lignin, 20-35 parts polybutylene succinate, 10-16 parts nano silica, 5-10 parts polyethyleneimine, 5-10 parts aluminum hypophosphite, 5-8 parts piperazine pyrophosphate, and 1-3 parts magnesium sulfate.

[0011] Preferably, the maintenance conditions for the fireproof door panel core in step (a) are as follows: regularly clean the dust on the surface of the door panel core with a soft cotton cloth, avoid high temperature, and maintain it for 1 day at a temperature of 15°C and a relative humidity of 90%.

[0012] Preferably, the wood used in step (b) is selected from one or more of pine, poplar, walnut and teak.

[0013] Preferably, the wood drying conditions in step (b) are high-frequency drying under vacuum at 60°C, with the moisture content controlled at 8-9%.

[0014] Preferably, the vacuum pressure flame retardant treatment conditions in step (b) are as follows: the door panel is placed in a vacuum can, the vacuum is drawn to -0.03MPa, then the flame retardant agent is added, and after the agent penetrates, the vacuum can is pressurized to 1.2MPa to further promote the diffusion of the agent into the wood. After 5 hours, the door panel is taken out and allowed to cure naturally or by heating, so that the agent is tightly bonded to the door panel.

[0015] More preferably, the flame retardant is disodium hydrogen phosphate.

[0016] Preferably, the modified lignin is prepared by: weighing a certain amount of enzymatically hydrolyzed lignin and adding it to an N,N-dimethylformamide solution, then adding pentaethylenehexamine and aminotrimethylphosphoric acid, reacting at 60°C for 0.5 hours, then adding benzaldehyde and continuing the reaction for 5 hours to obtain the product, subjecting the product to alkaline extraction and acid precipitation, filtering, washing with ethyl acetate three times, drying, and pulverizing to obtain the modified lignin.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] This invention provides a flame-retardant and fireproof wooden door and its preparation method. By adding modified lignin to the door panel core, the wood door is effectively protected from further combustion, the heat release rate is reduced, and the smoke suppression performance is improved. This extends the ignition time of the door and gives the flame-retardant wooden door better heat resistance and chemical stability. The fire resistance time is increased to 6.5–7.1 hours. In the event of a fire, the flames cannot penetrate the door body, effectively preventing the spread of fire and providing a flame-retardant effect, thus buying time for escape. Detailed Implementation

[0019] The embodiments of the technical solution of the present invention will be described in detail below with reference to the examples. The following embodiments are only used to illustrate the technical solution of the present invention more clearly, and are therefore only examples, and should not be used to limit the scope of protection of the present invention.

[0020] It should be noted that, unless otherwise specified, the experimental methods used in the implementation examples are all conventional methods; and the materials and reagents used are all commercially available unless otherwise specified.

[0021] In this invention, unless otherwise stated, all “parts” and percentages (%) refer to weight percentages.

[0022] In this invention, unless otherwise stated, the sum of all percentages in all compositions is 100%.

[0023] In this invention, unless otherwise stated, the numerical range "a~b" represents an abbreviation of any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0~5" means that all real numbers between "0~5" have been listed herein, and "0~5" is simply an abbreviation of these numerical combinations.

[0024] In this invention, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined to form new technical solutions.

[0025] In this invention, unless otherwise specified, all steps mentioned herein may be performed sequentially or randomly, but are preferably performed sequentially; for example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially; for example, the method may also include step (c), indicating that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0026] In this invention, unless otherwise specified, the specific values ​​and substances in the embodiments of this invention can be combined with other features in the description of this invention; for example, if the specification mentions that the reaction temperature is 10 to 100°C, while the embodiment mentions that the reaction temperature is 20°C, then it can be considered that this invention has specifically disclosed the range of 10 to 20°C, or the range of 20 to 100°C, and this range can be combined with other features in the description to form a new technical solution.

[0027] Preparation of modified lignin

[0028] Weigh 5 kg of enzymatically hydrolyzed lignin and add it to an appropriate amount of N,N-dimethylformamide solution. Then add pentaethylenehexamine and aminotrimethylphosphoric acid and react at 60°C for 0.5 hours. Then add 0.92 kg of benzaldehyde and continue the reaction for 5 hours to obtain the product. The product is subjected to alkaline extraction and acid precipitation, filtered, washed three times with ethyl acetate, dried, and pulverized to obtain modified lignin.

[0029] Example 1;

[0030] Step (a) Preparation of fireproof door core board: Weigh 30 parts of modified lignin, 24 parts of polybutylene succinate, 15 parts of nano silica, 10 parts of polyethyleneimine, 10 parts of aluminum hypophosphite, 8 parts of piperazine pyrophosphate, 3 parts of magnesium sulfate and glycerol according to the specified parts and mix them evenly. Heat the mixture to 90°C under stirring and react for 2 hours to obtain a slurry. Pour the slurry into a mold and cure it. Remove the mold after 3-4 hours. Use a soft cotton cloth to clean the dust on the surface of the door core regularly. Avoid high temperature exposure. Cure it for 1 day at a temperature of 15°C and a relative humidity of 90% to obtain the fireproof door core.

[0031] Step (b) Preparation of decorative solid wood door veneer: Select pine wood without internal cracks, knots, rot, or blue stain. Dry the wood at high frequency under vacuum at 60℃, controlling the moisture content to 8-9%, and then perform rough planing. Cut the wood to the required size to obtain the door panel. Then, place the door panel in a vacuum chamber and evacuate it to -0.03MPa. Add disodium hydrogen phosphate solution. After the agent penetrates, pressurize the vacuum chamber to 1.2MPa to further promote the diffusion of the agent into the wood. Keep it for 5 hours, remove the door panel, and allow it to cure naturally or by heating to ensure that the agent is tightly bonded to the door panel. Then polish it, wipe the surface dust clean, and spray paint and touch up the color on one side of the door panel.

[0032] Step (c) The door core panel and the decorative solid wood door skin are combined to form a flame-retardant and fireproof wooden door: After applying two-component epoxy resin glue to the two decorative door panels respectively, they are attached to both sides of the door core panel and sealed with solid wood strips. After high temperature and hot pressing, the door body is made and the excess glue is sanded off.

[0033] Step (d) Check the packaging: Check whether the overall color matching of the flame-retardant and fireproof wooden door is harmonious and consistent, check whether the surface of the door panel is smooth, repair any defects, wipe the dust off the surface of the wooden door, pack it and put it into the warehouse for storage.

[0034] Example 2;

[0035] Step (a) Preparation of fireproof door core board: Weigh 30 parts of modified lignin, 24 parts of polybutylene succinate, 15 parts of nano silica, 10 parts of polyethyleneimine, 10 parts of aluminum hypophosphite, 8 parts of piperazine pyrophosphate, 3 parts of magnesium sulfate and glycerol according to the specified parts and mix them evenly. Heat the mixture to 90°C under stirring and react for 2 hours to obtain a slurry. Pour the slurry into a mold and cure it. Remove the mold after 3-4 hours. Use a soft cotton cloth to clean the dust on the surface of the door core regularly. Avoid high temperature exposure. Cure it for 1 day at a temperature of 15°C and a relative humidity of 90% to obtain the fireproof door core.

[0036] Step (b) Preparation of decorative solid wood door veneer: Select poplar wood without internal cracks, knots, rot, or blue stain. Dry the wood at high frequency under vacuum at 60℃, controlling the moisture content to 8-9%, and then perform rough planing. Cut the wood to the required size to obtain the door panel. Then, place the door panel in a vacuum chamber and evacuate it to -0.03MPa. Add disodium hydrogen phosphate solution. After the agent penetrates, pressurize the vacuum chamber to 1.2MPa to further promote the diffusion of the agent into the wood. Keep it for 5 hours, remove the door panel, and allow it to cure naturally or by heating to ensure that the agent is tightly bonded to the door panel. Then polish it, wipe the dust off the surface, and spray paint and touch up the color on one side of the door panel.

[0037] Step (c) The door core panel and the decorative solid wood door skin are combined to form a flame-retardant and fireproof wooden door: After applying two-component epoxy resin glue to the two decorative door panels respectively, they are attached to both sides of the door core panel and sealed with solid wood strips. After high temperature and hot pressing, the door body is made and the excess glue is sanded off.

[0038] Step (d) Check the packaging: Check whether the overall color matching of the flame-retardant and fireproof wooden door is harmonious and consistent, check whether the surface of the door panel is smooth, repair any defects, wipe the dust off the surface of the wooden door, pack it and put it into the warehouse for storage.

[0039] Example 3;

[0040] Step (a) Preparation of fireproof door core board: Weigh 32 parts of modified lignin, 28 parts of polybutylene succinate, 12 parts of nano silica, 8 parts of polyethyleneimine, 9 parts of aluminum hypophosphite, 8 parts of piperazine pyrophosphate, 3 parts of magnesium sulfate and glycerol according to the proportions, mix evenly, heat to 90°C under stirring, react for 2 hours to obtain slurry, inject the slurry into the mold for curing, remove the mold after 3-4 hours, use a soft cotton cloth to clean the dust on the surface of the door core regularly, avoid high temperature, and cure for 1 day at a temperature of 15°C and a relative humidity of 90% to obtain fireproof door core board;

[0041] Step (b) Preparation of decorative solid wood door veneer: Select pine wood without internal cracks, knots, rot, or blue stain. Dry the wood at high frequency under vacuum at 60℃, controlling the moisture content to 8-9%, and then perform rough planing. Cut the wood to the required size to obtain the door panel. Then, place the door panel in a vacuum chamber and evacuate it to -0.03MPa. Add disodium hydrogen phosphate solution. After the agent penetrates, pressurize the vacuum chamber to 1.2MPa to further promote the diffusion of the agent into the wood. Keep it for 5 hours, remove the door panel, and allow it to cure naturally or by heating to ensure that the agent is tightly bonded to the door panel. Then polish it, wipe the surface dust clean, and spray paint and touch up the color on one side of the door panel.

[0042] Step (c) The door core panel and the decorative solid wood door skin are combined to form a flame-retardant and fireproof wooden door: After applying two-component epoxy resin glue to the two decorative door panels respectively, they are attached to both sides of the door core panel and sealed with solid wood strips. After high temperature and hot pressing, the door body is made and the excess glue is sanded off.

[0043] Step (d) Check the packaging: Check whether the overall color matching of the flame-retardant and fireproof wooden door is harmonious and consistent, check whether the surface of the door panel is smooth, repair any defects, wipe the dust off the surface of the wooden door, pack it and put it into the warehouse for storage.

[0044] Example 4;

[0045] Step (a) Preparation of fireproof door core board: Weigh 32 parts of modified lignin, 28 parts of polybutylene succinate, 12 parts of nano silica, 8 parts of polyethyleneimine, 9 parts of aluminum hypophosphite, 8 parts of piperazine pyrophosphate, 3 parts of magnesium sulfate and glycerol according to the proportions, mix evenly, heat to 90°C under stirring, react for 2 hours to obtain slurry, inject the slurry into the mold for curing, remove the mold after 3-4 hours, use a soft cotton cloth to clean the dust on the surface of the door core regularly, avoid high temperature, and cure for 1 day at a temperature of 15°C and a relative humidity of 90% to obtain fireproof door core board;

[0046] Step (b) Preparation of decorative solid wood door veneer: Select walnut wood without internal cracks, knots, rot, or blue stain. Dry the wood at high frequency under vacuum at 60℃, controlling the moisture content to 8-9%, and then perform rough planing. Cut the wood to the required size to obtain the door panel. Then, place the door panel in a vacuum chamber and evacuate it to -0.03MPa. Add disodium hydrogen phosphate solution. After the agent penetrates, pressurize the vacuum chamber to 1.2MPa to further promote the diffusion of the agent into the wood. Keep it for 5 hours, remove the door panel, and allow it to cure naturally or by heating to ensure that the agent is tightly bonded to the door panel. Then polish it, wipe the dust off the surface, and spray paint and touch up the color on one side of the door panel.

[0047] Step (c) The door core panel and the decorative solid wood door skin are combined to form a flame-retardant and fireproof wooden door: After applying two-component epoxy resin glue to the two decorative door panels respectively, they are attached to both sides of the door core panel and sealed with solid wood strips. After high temperature and hot pressing, the door body is made and the excess glue is sanded off.

[0048] Step (d) Check the packaging: Check whether the overall color matching of the flame-retardant and fireproof wooden door is harmonious and consistent, check whether the surface of the door panel is smooth, repair any defects, wipe the dust off the surface of the wooden door, pack it and put it into the warehouse for storage.

[0049] Example 5

[0050] Step (a) Preparation of fireproof door core board: Weigh 35 parts of modified lignin, 20 parts of polybutylene succinate, 15 parts of nano silica, 8 parts of polyethyleneimine, 8 parts of aluminum hypophosphite, 7 parts of piperazine pyrophosphate, 2 parts of magnesium sulfate and glycerol according to the specified proportions, mix them evenly, heat to 90°C under stirring, react for 2 hours to obtain slurry, inject the slurry into the mold for curing, remove the mold after 3-4 hours, use a soft cotton cloth to clean the dust on the surface of the door core regularly, avoid high temperature, and cure for 1 day at a temperature of 15°C and a relative humidity of 90% to obtain fireproof door core board;

[0051] Step (b) Preparation of decorative solid wood door veneer: Select pine wood without internal cracks, knots, rot, or blue stain. Dry the wood at high frequency under vacuum at 60℃, controlling the moisture content to 8-9%, and then perform rough planing. Cut the wood to the required size to obtain the door panel. Then, place the door panel in a vacuum chamber and evacuate it to -0.03MPa. Add disodium hydrogen phosphate solution. After the agent penetrates, pressurize the vacuum chamber to 1.2MPa to further promote the diffusion of the agent into the wood. Keep it for 5 hours, remove the door panel, and allow it to cure naturally or by heating to ensure that the agent is tightly bonded to the door panel. Then polish it, wipe the surface dust clean, and spray paint and touch up the color on one side of the door panel.

[0052] Step (c) The door core panel and the decorative solid wood door skin are combined to form a flame-retardant and fireproof wooden door: After applying two-component epoxy resin glue to the two decorative door panels respectively, they are attached to both sides of the door core panel and sealed with solid wood strips. After high temperature and hot pressing, the door body is made and the excess glue is sanded off.

[0053] Step (d) Check the packaging: Check whether the overall color matching of the flame-retardant and fireproof wooden door is harmonious and consistent, check whether the surface of the door panel is smooth, repair any defects, wipe the dust off the surface of the wooden door, pack it and put it into the warehouse for storage.

[0054] Comparative Example 1

[0055] The difference between this comparative example and the embodiment is that the modified lignin in step (a) is ordinary lignin, while the remaining steps are the same as in embodiment one.

[0056] Performance testing

[0057] The flame-retardant and fireproof wooden doors prepared according to Examples 1 to 5 and Comparative Examples 1 to 2 of the present invention were subjected to performance tests, and the experimental results are shown in Table 1.

[0058] Table 1. Performance test results of flame-retardant and fireproof wooden doors

[0059] Serial Number Refractory time / h Moisture absorption and halogenation Flame retardant rating / class Example 1 6.9 none A Example 2 6.5 none A Example 3 7.1 none A Example 4 6.8 none A Example 5 7.0 none A Comparative Example 1 1.5 none B1

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A method for preparing a fire-retardant fireproof wooden door, characterized in that, Includes the following steps: Step (a) Preparation of fireproof door core board: Weigh the required raw materials and glycerol according to the proportions, mix them evenly, heat to 90°C under stirring, react for 2 hours to obtain slurry, inject the slurry into the mold for curing, remove the mold after 3-4 hours, and cure under certain conditions to obtain fireproof door core board; Step (b) Preparation of decorative solid wood door veneer: Select wood without internal cracks, knots, rotten wood, or blue stain. After drying the wood, perform rough planing and cut the wood to the required size to obtain the door panel. Then, vacuum pressurize the door panel to inject flame retardant, polish it, wipe the dust off the surface, and spray paint and color-correct one side of the door panel. Step (c) The door core panel and the decorative solid wood door skin are combined to form a flame-retardant and fireproof wooden door: After applying two-component epoxy resin glue to the two decorative door panels respectively, they are attached to both sides of the door core panel and sealed with solid wood strips. After high temperature and hot pressing, the door body is made and the excess glue is sanded off. Step (d) Check the packaging: Check whether the overall color matching of the flame-retardant and fireproof wooden door is harmonious and consistent, check whether the surface of the door panel is smooth, repair any defects, wipe the dust off the surface of the wooden door, pack it and put it into the warehouse for storage. The raw material composition includes: 30-35 parts modified lignin, 20-35 parts polybutylene succinate, 10-16 parts nano silica, 5-10 parts polyethyleneimine, 5-10 parts aluminum hypophosphite, 5-8 parts piperazine pyrophosphate, and 1-3 parts magnesium sulfate.

2. The method for preparing a flame-retardant and fireproof wooden door according to claim 1, characterized in that, The maintenance conditions for the fireproof door panel core in step (a) are as follows: use a soft cotton cloth to regularly clean the dust on the surface of the door panel core, avoid high temperature, and maintain it for 1 day at a temperature of 15℃ and a relative humidity of 90%.

3. The method for preparing a flame-retardant and fireproof wooden door according to claim 1, characterized in that, The wood used in step (b) is selected from one or more of pine, poplar, walnut and teak.

4. The method for preparing a flame-retardant and fireproof wooden door according to claim 1, characterized in that, The wood drying conditions in step (b) are high-frequency drying under vacuum at 60°C, with the moisture content controlled at 8-9%.

5. The method for preparing a flame-retardant and fireproof wooden door according to claim 1, characterized in that, The treatment conditions for vacuum pressure flame retardant filling in step (b) are as follows: place the door panel in a vacuum can, evacuate to -0.03MPa, then add flame retardant agent. After the agent penetrates, pressurize the vacuum can to 1.2MPa to further promote the diffusion of the agent into the wood. Keep it for 5 hours, then take out the door panel and allow it to cure naturally or by heating to ensure that the agent is tightly bonded to the door panel.

6. The method for preparing a flame-retardant and fireproof wooden door according to claim 5, characterized in that, The flame retardant agent is disodium hydrogen phosphate.

7. The method for preparing a flame-retardant and fireproof wooden door according to claim 1, characterized in that, The modified lignin is prepared by weighing a certain amount of enzymatically hydrolyzed lignin and adding it to an N,N-dimethylformamide solution. Then, pentaethylenehexamine and aminotrimethylphosphoric acid are added to it, and the reaction is carried out at 60°C for 0.5 hours. Then, benzaldehyde is added to it and the reaction is continued for 5 hours to obtain the product. The product is subjected to alkaline extraction and acid precipitation, filtered, washed three times with ethyl acetate, dried, and pulverized to obtain the modified lignin.

8. A flame-retardant and fireproof wooden door, characterized in that, It is prepared by the preparation method according to any one of claims 1 to 7.