CN112265092B - Method for simply manufacturing environment-friendly flame-retardant wood and improving mechanical property of environment-friendly flame-retardant wood - Google Patents

Method for simply manufacturing environment-friendly flame-retardant wood and improving mechanical property of environment-friendly flame-retardant wood Download PDF

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Publication number
CN112265092B
CN112265092B CN202011122977.2A CN202011122977A CN112265092B CN 112265092 B CN112265092 B CN 112265092B CN 202011122977 A CN202011122977 A CN 202011122977A CN 112265092 B CN112265092 B CN 112265092B
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wood
phytic acid
flame
uracil
retardant
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CN112265092A (en
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邹美帅
张立晨
李晓东
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Beijing Institute of Technology BIT
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Beijing Institute of Technology BIT
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B27WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27KPROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
    • B27K3/00Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
    • B27K3/02Processes; Apparatus
    • B27K3/025Controlling the process
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B27WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27KPROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
    • B27K3/00Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
    • B27K3/34Organic impregnating agents
    • B27K3/343Heterocyclic compounds
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B27WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27KPROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
    • B27K3/00Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
    • B27K3/34Organic impregnating agents
    • B27K3/36Aliphatic compounds
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B27WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27KPROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
    • B27K3/00Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
    • B27K3/34Organic impregnating agents
    • B27K3/50Mixtures of different organic impregnating agents
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B27WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27KPROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
    • B27K5/00Treating of wood not provided for in groups B27K1/00, B27K3/00
    • B27K5/04Combined bleaching or impregnating and drying of wood
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B27WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27KPROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
    • B27K2240/00Purpose of the treatment
    • B27K2240/30Fireproofing

Abstract

The invention relates to a method for simply manufacturing environment-friendly flame-retardant wood and simultaneously improving the mechanical property of the environment-friendly flame-retardant wood, belonging to the technical field of material processing. Adding one part of uracil and 40-100 parts of solvent into a glass container, controlling the temperature of the reactor to be 50-90 ℃, and stirring for 10min (minutes) to 2h (hours) under heat preservation; adding 1-5 parts of phytic acid into a glass container, and stirring for 10 min-1 h. Soaking wood in a certain shape in a solution in a glass container for 30 min-3 h, taking out, washing with distilled water and ethanol for multiple times, and drying to obtain the flame-retardant wood with improved mechanical properties. The invention is simple to operate, can realize the purpose of green flame retardance only by soaking wood in the mixed solution of phytic acid and uracil, is very suitable for expanding production, and improves the mechanical property of the wood.

Description

Method for simply manufacturing environment-friendly flame-retardant wood and improving mechanical property of environment-friendly flame-retardant wood
Technical Field
The invention relates to a method for simply manufacturing environment-friendly flame-retardant wood and simultaneously improving the mechanical property of the environment-friendly flame-retardant wood, belonging to the technical field of material processing.
Background
Wood is one of the most abundant, oldest and sustainable natural materials on earth. The wood has the advantages of light weight, high strength, low cost and the like, so the wood is widely used in the industries of building materials, thermal energy, transportation, furniture, decoration and the like. However, the flammability of wood limits its use in the building and furniture fields, especially in densely populated areas. Therefore, there is a need for flame retardant treatment of wood products. The conventional method for preparing flame-retardant wood is to impregnate halogenated flame retardant, phenolic resin or melamine formaldehyde resin into wood pores through physical penetration. However, these compounds constantly release harmful organic compounds, such as halogens, formaldehyde and phenol, which do not meet the environmental and health requirements. Many researchers at home and abroad use a bio-mineral struvite permeation technology to prepare a magnesium-aluminum Layer Double Hydroxide (LDH) coating or impregnate montmorillonite clay into wood cell walls to prepare the environment-friendly wood with flame retardance. However, too much struvite results in a decrease in the mechanical properties of the wood, and nano-coatings and clays can be too expensive for industrialization. Therefore, there is an urgent need to obtain flame retardant wood with enhanced mechanical properties in an environmentally friendly, low cost and convenient manner. The invention takes common poplar as a research object. Poplar consists approximately of 40-50% cellulose, 20-35% hemicellulose and 15-30% lignin and some fiber derivatives. Cellulose and lignin are widely used as biomass carbon sources in Intumescent Flame Retardant (IFR) systems. Generally, IFR comprises mainly three parts, acid source, gas source and carbon source. In order to form an intumescent flame retardant system, an environmentally friendly acid and gas source is still required.
Phytic acid (Phytic acid) is an organic phosphoric acid compound extracted from plant seeds, and has a molecular formula of C6H18O24P6. The product is light yellow to light brown slurry liquid, and is easily soluble in water, ethanol and acetone. Phytic acid is a strong acid, has strong chelating ability, and has 6 phosphate radicals with negative electricity. Due to the characteristics of biocompatibility, renewability and rich phosphorus, the phytic acid is very suitable for being used as a flame-retardant additive material, thereby causing wide attention of people. And the phytic acid is obtained by distilling grains and beans, so that the method is very environment-friendly. PA is used as an acid source and can interact with molecules with positive charges, so that the PA is widely used for constructing a layer-by-layer self-assembly (LbL) flame retardant system, a synthetic polyelectrolyte complex flame retardant system and the like.
The appearance of Uracil (Uracil) is white or light yellow needle crystal with chemical formula C4H4N2O2The melting point is 338 ℃, and the water soluble type ammonia water insoluble type ethanol and ether. Uracil is a unique base of RNA and is one of the four constituent bases that make up RNA. The nitrogenous base is a nitrogenous substance with good thermal stability in nature, and can release gas in the combustion process like melamine, so that uracil can be used as a gas source of IFR. Wang et al used uracil as a biobased gas source to modulate the efficiency of IFR in polypropylene (Wang Z, Liu Y, Li J. regulating effects of nitrogenes bases on the character structure and flame recovery of polypropylene/endogenous flame recovery compositions [ J]ACS Sustainable chem. Eng.2017,5(3), 2375-2383). At present, the research of flame-retardant wood by using phytic acid as an acid source in an intumescent flame-retardant system and uracil as a gas source is not carried out, and the invention provides a new and simple environment-friendly flame-retardant woodAnd an industrial production method.
Disclosure of Invention
The invention aims to provide a method for simply and quickly manufacturing green environment-friendly flame-retardant wood and enhancing the mechanical property of the green environment-friendly flame-retardant wood.
The phytic acid is used as an acid source in an intumescent flame retardant system, the uracil is used as a gas source, cellulose and lignin of poplar are used as carbon sources, and the cellulose and the lignin are combined through hydrogen bond action to form a green intumescent flame retardant system.
The purpose of the invention is realized by the following technical scheme.
The invention relates to a method for simply manufacturing green environment-friendly flame-retardant wood and simultaneously improving the mechanical property of the wood, which is formed by combining poplar, phytic acid and uracil through hydrogen bond action, and the wood comprises the following components in percentage by mass: 60-90% of poplar, 5-20% of phytic acid and 5-20% of uracil.
The invention relates to a method for simply manufacturing green environment-friendly flame-retardant wood and simultaneously improving the mechanical property of the green environment-friendly flame-retardant wood, which comprises the following steps:
1) adding uracil and a solvent into a glass container, stirring and heating for reaction, controlling the temperature of the reactor to be 50-90 ℃, and stirring for 10 min-2 h under the condition of heat preservation to obtain a transparent solution;
2) adding phytic acid into a glass container, and stirring for 10 min-1 h to obtain a uniformly mixed phytic uracil mixed solution;
3) soaking poplar in a certain shape in the mixed solution obtained in the step 2), controlling the temperature of a glass container to be 50-90 ℃, stirring, and carrying out heat preservation reaction for 30 min-3 h;
4) taking out the wood blocks obtained in the step 3), washing the wood blocks with distilled water and ethanol for multiple times, and then drying the wood blocks to obtain the flame-retardant wood.
The mass ratio of uracil to solvent in step 1) above is 1 g: 40-100 mL;
the phytic acid used in the above step 2) was 50% in H2O,70%in H2One or a mixture of O, and the addition amount of the phytic acid is 1 to 5 grams;
the solvent used in the step 1) is one or a mixture of ethanol, acetic acid and deionized water;
the invention has the bright points that: the wood can obtain the flame retardant property by simply soaking in the mixed solution of the phytic acid and the uracil, and the mechanical property is improved. This opens up a new way of making fire retardant wood. The mechanical properties of the obtained product are shown in figure 1, and the flame retardant properties are shown in figure 2. The method has the advantages of simple process, easily obtained raw materials, low cost, environmental protection and capability of obviously improving the flame retardant property and the mechanical property of the wood.
Drawings
Fig. 1 is a graph showing the mechanical properties of untreated wood and the flame-retardant wood prepared in example 1, and fig. 2 is a graph showing the flame-retardant properties of untreated wood and the flame-retardant wood prepared in example 1.
Detailed Description
The present invention is further illustrated by the following examples, which are not intended to limit the scope of the invention.
Example 1
Adding one part of uracil and 80 parts of distilled water into a glass container, uniformly stirring, heating to 70 ℃, and keeping the temperature and stirring for 30min to obtain a transparent solution; adding 2 parts by mass of phytic acid into a glass container, and stirring for 1 hour to obtain a uniformly mixed solution; soaking wood in certain shape in the solution for 2h, and stirring and maintaining the temperature; and taking out the wood blocks, washing the wood blocks for multiple times by using distilled water, and drying the wood blocks in a blast oven to obtain the flame-retardant wood.
As can be seen from the mechanical property curve of the untreated wood and the flame-retardant wood, the compression strength of the flame-retardant wood is improved by 15.3 percent compared with that of the untreated natural wood, and the modulus of rupture of the flame-retardant wood and the untreated natural wood is basically consistent. The mechanical property of the flame-retardant wood treated by the phytic acid and the uracil is improved. From the fire retardant performance curve of fig. two, the limited oxygen index of the fire-retardant wood is 31.8%, and UL94 is a V0 grade, while the limited oxygen index of the untreated natural wood is only 22%, and UL94 is not grade, and the peak value of the heat release rate is reduced by 41.2% compared with the untreated wood. The two figures illustrate that a method of simply manufacturing green environment-friendly flame-retardant wood and simultaneously improving the mechanical properties thereof according to the present invention is effective.
Example 2
Adding one part by mass of uracil and 60 parts by mass of distilled water into a glass container, uniformly stirring, heating to 90 ℃, and keeping the temperature and stirring for 10min to obtain a transparent solution; adding 1.5 parts by mass of phytic acid into a glass container, and stirring for 1 hour to obtain a uniformly mixed solution; soaking wood in certain shape in the solution for 2h, and stirring and maintaining the temperature; and taking out the wood blocks, washing the wood blocks for multiple times by using distilled water, and drying the wood blocks in a blast oven to obtain the flame-retardant wood.
Example 3
Adding one part of uracil and 100 parts of distilled water into a glass container, uniformly stirring, heating to 70 ℃, and stirring for 1 hour under the condition of heat preservation to obtain a transparent solution; adding 2 parts by mass of phytic acid into a glass container, and stirring for 1 hour to obtain a uniformly mixed solution; soaking wood in certain shape in the solution for 3h, and stirring and maintaining the temperature; and taking out the wood blocks, washing the wood blocks for multiple times by using distilled water, and drying the wood blocks in a blast oven to obtain the flame-retardant wood.
Example 4
Adding one part of uracil and 40 parts of distilled water into a glass container, uniformly stirring, heating to 50 ℃, and stirring for 2 hours under heat preservation to obtain a transparent solution; adding 5 parts by mass of phytic acid into a glass container, and stirring for 1 hour to obtain a uniformly mixed solution; soaking wood in certain shape in the solution for 2h, and stirring and maintaining the temperature; and taking out the wood blocks, washing the wood blocks for multiple times by using distilled water, and drying the wood blocks in a blast oven to obtain the flame-retardant wood.
Example 5
Adding one part of uracil and 60 parts of distilled water into a glass container, uniformly stirring, heating to 80 ℃, and stirring for 1 hour under the condition of heat preservation to obtain a transparent solution; adding 1.5 parts by mass of phytic acid into a glass container, and stirring for 1 hour to obtain a uniformly mixed solution; soaking wood in certain shape in the solution for 2h, and stirring and maintaining the temperature; and taking out the wood blocks, washing the wood blocks for multiple times by using distilled water, and drying the wood blocks in a blast oven to obtain the flame-retardant wood.
Example 6
Adding one part of uracil and 60 parts of distilled water into a glass container, uniformly stirring, heating to 80 ℃, and stirring for 1 hour under the condition of heat preservation to obtain a transparent solution; adding 1 part by mass of phytic acid into a glass container, and stirring for 10min to obtain a uniformly mixed solution; soaking the wood with a certain shape in the solution for 30min, and simultaneously stirring and preserving heat; and taking out the wood blocks, washing the wood blocks for multiple times by using distilled water, and drying the wood blocks in a blast oven to obtain the flame-retardant wood.

Claims (4)

1. A method for simply manufacturing green environment-friendly flame-retardant wood and simultaneously improving the mechanical property of the green environment-friendly flame-retardant wood is characterized by comprising the following steps: the wood is soaked in a mixed solution of phytic acid and uracil, the wood, the phytic acid and the uracil are combined through hydrogen bond, and the flame-retardant wood comprises the following components in percentage by mass:
60-90% of poplar
5 to 20 percent of phytic acid
5% -20% of uracil.
2. A method for simply manufacturing green environment-friendly flame-retardant wood and simultaneously improving the mechanical property of the green environment-friendly flame-retardant wood is characterized by comprising the following specific preparation steps:
1) adding uracil and a solvent into a glass container, stirring and heating for reaction, controlling the temperature of the reactor to be 50-90 ℃, and stirring for 10 min-2 h while keeping the temperature to obtain a transparent solution:
2) adding phytic acid into a glass container, and stirring for 10 min-l h to obtain a uniformly mixed phytic acid uracil mixed solution;
3) soaking poplar in a certain shape in the mixed solution obtained in the step 2), controlling the temperature of a glass container to be 50-90 ℃, and stirring and carrying out heat preservation reaction for 30 min-3 h;
4) taking out the wood blocks in the step 3), washing the wood blocks with distilled water and ethanol for multiple times, and then drying the wood blocks to obtain the flame-retardant wood;
the mass volume ratio of the uracil to the solvent in the step 1) is 1 g: 40-100 mL;
the phytic acid used in the step 2) is one of a 50% phytic acid aqueous solution and a 70% phytic acid aqueous solution or a mixture of the 50% phytic acid aqueous solution and the 70% phytic acid aqueous solution, and the addition amount of the phytic acid is 1-5 g;
the solvent used in the step 1) is one or a mixture of ethanol, acetic acid and deionized water;
3. the method for simply manufacturing the green environmental-friendly flame-retardant wood while improving the mechanical properties thereof as claimed in claim 2, wherein: the glass container is provided with a temperature control device and a stirring device.
4. The method for simply manufacturing the green environmental-friendly flame-retardant wood while improving the mechanical properties thereof as claimed in claim 2, wherein: the uracil in step 1) is exchanged with the phytic acid in step 2), and the rest steps are unchanged.
CN202011122977.2A 2020-10-20 2020-10-20 Method for simply manufacturing environment-friendly flame-retardant wood and improving mechanical property of environment-friendly flame-retardant wood Active CN112265092B (en)

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SG10201504031VA (en) * 2006-10-26 2015-06-29 Xyleco Inc Processing biomass
CN106750893B (en) * 2016-11-18 2019-10-11 中国科学院宁波材料技术与工程研究所 A kind of anti-flaming polyolefin composition biology base gas source it and constituted
CN109400957B (en) * 2018-07-19 2020-11-27 中国科学院宁波材料技术与工程研究所 Alkaloid phosphate flame retardant and preparation method thereof
CN110524657A (en) * 2019-08-29 2019-12-03 北京林业大学 A kind of phytic acid fire retarding wood and preparation method thereof

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