阅读说明：本技术 低烟毒阻燃纤维板及其制备方法 (Low-smoke-toxicity flame-retardant fiberboard and preparation method thereof ) 是由 李碧英 朱剑 颜明强 甘子琼 王甫正 王文涛 钱伟平 文桂英 于 2021-09-14 设计创作，主要内容包括：本发明属于人造板材技术领域,具体涉及一种纤维板及其制备方法。其中一种低烟毒阻燃纤维板,包括：木纤维和阻燃胶黏剂；阻燃胶黏剂包括：树脂胶黏剂；低烟毒复合阻燃剂。本发明可在高层建筑、公共场所用室内装饰装修、家具制造中广泛应用,可有效解决当前歌舞娱乐场所、高层建筑等场所使用纤维板存在的火灾危险性高、产烟量大、产烟毒性不合格,贮存和使用过程中纤维板易发生霉变以及易变色等技术难题。(The invention belongs to the technical field of artificial boards, and particularly relates to a fiberboard and a preparation method thereof. One of them low smoke and toxicity fire-retardant fiberboard includes: wood fiber and flame retardant adhesive; the flame-retardant adhesive comprises: resin adhesive; a low-smoke composite flame retardant. The invention can be widely applied to indoor decoration and fitment and furniture manufacture in high-rise buildings and public places, and can effectively solve the technical problems of high fire hazard, large smoke production, unqualified smoke production toxicity, easy mildew and easy color generation of the fiberboard in the storage and use processes and the like in the current occasions such as singing, dancing, entertainment places, high-rise buildings and the like.)

1. A low smoke flame retardant fiberboard comprising: wood fiber and flame retardant adhesive;

the flame-retardant adhesive is characterized by comprising the following components in percentage by weight:

an aqueous resin adhesive solution;

a low-smoke composite flame retardant.

2. The low smoke toxicity flame retardant fiber board of claim 1, wherein the moisture content of the wood fiber is below 7%;

the aqueous resin adhesive solution is 25 to 60 percent, preferably 30 to 55 percent, by weight of the wood fiber;

the low-smoke composite flame retardant accounts for 3-30% of the weight of the wood fiber, and preferably accounts for 5-25%.

3. The low smoke toxicity flame retardant fiberboard of claim 1, wherein the aqueous resin adhesive solution is at least one of an aqueous urea formaldehyde resin adhesive solution or an aqueous melamine modified urea formaldehyde resin adhesive solution.

4. The low smoke toxicity flame retardant fiberboard of claim 1, wherein the low smoke toxicity composite flame retardant comprises the following raw materials:

ammonium phosphate, boric acid, borate, flame retardant synergist and smoke suppressant;

the smoke suppressant is at least one of a smoke suppressant synergist or a smoke suppressant adsorbent;

the low-smoke-toxicity composite flame retardant comprises the following raw materials in parts by weight based on 100 parts by weight of the low-smoke-toxicity composite flame retardant:

10-50 parts of ammonium phosphate salt, preferably 15-40 parts;

10-55 parts of boric acid, preferably 15-45 parts;

10-55 parts of borate, preferably 15-45 parts;

5-30 parts of flame-retardant synergist, preferably 10-28 parts;

2-30 parts of smoke suppression synergist or 1-15 parts of smoke suppression adsorbent, and preferably 5-25 parts of smoke suppression synergist or preferably 3-10 parts of smoke suppression adsorbent.

5. The low smoke toxicity flame retardant fiber board of claim 4, wherein said ammonium phosphate salt is at least one of ammonium polyphosphate, ammonium monohydrogen phosphate or ammonium dihydrogen phosphate;

the borate is at least one of borax, zinc borate, calcium borate or copper borate;

the flame-retardant synergist is at least one of organic nano montmorillonite, organic silicon flame retardant, melamine cyanurate, melamine phosphate, melamine pyrophosphate, dipentaerythritol triphosphate melamine salt, dipentaerythritol phosphate melamine salt or dipentaerythritol diphosphate dihydrogen melamine salt;

the smoke suppression synergist is at least one of copper hydroxide, copper oxide, cuprous oxide, malachite, chalcopyrite, ammonium molybdate, zinc molybdate, molybdenum oxide, ferrocene, iron oxide, cadmium oxide or zinc oxide;

the smoke suppression adsorbent is at least one of a molecular sieve, graphene or aerogel.

6. The low smoke toxicity flame retardant fiberboard of claim 4, wherein the surface of the raw material of the low smoke toxicity composite flame retardant is further subjected to surface modification treatment by using a surface modifier;

the surface modifier is a surface modifier solution with the concentration of 0.8-2.0%, preferably 1.0-1.5%;

the surface modifier is at least one of silane coupling agent, titanate coupling agent, aluminate coupling agent or organic silicon;

the weight of the surface modifier is 0.1-1.5%, preferably 0.2-1.2% of the weight of the low-smoke composite flame retardant.

7. A method for preparing a low smoke toxicity flame retardant fiber board according to any one of claims 1 to 6, characterized by comprising the following steps:

1) weighing a resin adhesive aqueous solution, adding a low smoke toxicity composite flame retardant under stirring to prepare a flame retardant adhesive solution;

2) mixing the dried and weighed wood fibers, spraying the flame-retardant adhesive solution under the condition of stirring, continuously stirring, taking out the wood fibers, and drying;

3) paving and shaping the dried wood fiber;

4) and (3) carrying out hot-press molding on the paved and shaped wood fibers, and carrying out trimming and polishing to obtain the low-smoke-toxicity flame-retardant fiberboard.

8. The method for preparing the low smoke toxicity flame retardant fiberboard of claim 7, wherein in the step 1), the low smoke toxicity composite flame retardant is prepared by the following method:

101) mixing the raw materials;

102) carrying out surface modification treatment on the raw materials in a mixed state;

103) and drying the raw materials subjected to surface modification to obtain the low-smoke-toxicity composite flame retardant.

9. A low smoke toxicity flame retardant fiber board and its preparation method according to claim 8, characterized in that, in step 101), the raw materials are added into a high speed mixer, and the mixing is performed for 3min to 15min, preferably 5min to 12min at the rotation speed of 200r/min to 450r/min, preferably 250r/min to 400r/min of the high speed mixer;

in the step 102), a surface modifier is adopted to carry out surface modification treatment on the raw material, wherein the weight of the surface modifier is 0.1% -1.5%, preferably 0.2% -1.2% of the weight of the low-smoke-toxicity composite flame retardant, the surface modifier is prepared into a 0.8% -2.0% concentration surface modifier solution, preferably 1.0% -1.5% concentration surface modifier solution, and in the raw material mixing process, the prepared surface modifier solution is completely sprayed on the surface of the raw material to realize the surface modification treatment on the raw material;

step 103), drying the surface-modified raw materials in an oven at the temperature of 80-95 ℃ for 20-50 min, preferably 25-45 min to obtain the low-smoke-toxicity composite flame retardant;

further comprising:

104) crushing the low-smoke-toxicity composite flame retardant to control the granularity of the low-smoke-toxicity composite flame retardant to be more than 150 meshes, preferably more than 200 meshes;

and 104), crushing the low-smoke-toxicity composite flame retardant in a ball mill at the rotating speed of 200 r/min-450 r/min, preferably at the rotating speed of 250 r/min-400 r/min for 20 min-40 min, preferably 25 min-35 min, and controlling the particle size to be more than 150 meshes, preferably more than 200 meshes.

10. The preparation method of the low smoke toxicity flame retardant fiber board according to claim 7, wherein in the step 1), the aqueous resin adhesive solution is at least one of an aqueous urea-formaldehyde resin adhesive solution or an aqueous melamine modified urea-formaldehyde resin adhesive solution, and the aqueous resin adhesive solution is an aqueous resin adhesive solution with a solid content of 30-60%, preferably 50%;

in the step 2), the water content of the wood fiber is below 7%, the wood fiber is placed into a high-speed mixer, the flame-retardant adhesive solution is sprayed under the stirring condition that the rotating speed of the high-speed mixer is 200 r/min-450 r/min, preferably 250 r/min-400 r/min, the wood fiber is continuously stirred for 5 min-20 min, preferably 8 min-15 min, the wood fiber is taken out and placed into an oven with the temperature of 70-100 ℃, preferably 80-95 ℃ for drying for 20 min-45 min, preferably 25 min-40 min;

in the step 4), conveying the paved and shaped wood fibers into a hot-pressing forming machine;

controlling the temperature of I-V areas of the hot-pressing forming machine: the first region is 235 +/-10 ℃, the second region is 230 +/-10 ℃, the third region is 225 +/-10 ℃, the fourth region is 215 +/-10 ℃ and the fourth region is 190 +/-10 ℃;

the pressure of 5 points in the control I area is respectively as follows: 7.5 plus or minus 2MPa, 13 plus or minus 2MPa, 23 plus or minus 2MPa and 20 plus or minus 2MPa, wherein each pressure point is 0.5-5 seconds, preferably 1-3 seconds;

the pressure of 5 points in the control II area is respectively as follows: 14.5 +/-2 MPa, 13.5 +/-2 MPa, 9.5 +/-2 MPa, 5.5 +/-2 MPa and 3.7 +/-2 MPa, wherein each pressure point is 0.5-5 seconds, preferably 1-3 seconds;

controlling the following 15 pressure points of the zone III, the zone IV and the zone V to be: 1.9 +/-1 MPa, and each pressure point is 0.5-5 seconds, preferably 1-3 seconds;

and finally, trimming and polishing the board subjected to hot press molding to obtain the low-smoke flame-retardant fiberboard.

Technical Field

The invention belongs to the technical field of artificial boards, and particularly relates to a fiberboard and a preparation method thereof.

Background

The fiberboard has good physical and mechanical properties and green environmental protection performance, and the product has the advantages of light weight, high strength, good insulativity, easy processing, pleasant appearance and the like, is widely used in the fields of furniture manufacturing, partitions, false walls, vehicle and ship manufacturing, household appliances and the like at present, and is one of the raw materials with the largest demand in furniture and interior decoration and decoration industries in China. However, since the common fiber boards are made of combustible materials, once open fire or overload power is used during decoration, a fire is very easy to initiate and spread rapidly, and a large amount of toxic smoke is generated during the fire, so that the smoke threatens human life and even exceeds the fire itself.

The patent CN101961879A is published, and a preparation method of a fiberboard composite flame retardant has the main problems that the flame retardant effect is not ideal enough, the combustion performance cannot reach B1 level, the flame retardant is easy to separate out and absorb moisture, the prepared fiberboard has large smoke yield, the smoke cannot reach ZA3 level, and the toxicity standard requirement cannot be met. On the other hand, the patent belongs to a flame retardant aqueous solution, and in the practical application process, the flame retardant aqueous solution is sprayed on the surface of the fiber for flame retardance, so that the drying load is increased, and the energy consumption is higher.

The patent CN02153877.8 is published, a medium density flame retardant fiber board and a manufacturing method thereof, the technology for preparing the medium density flame retardant fiber board is complex, the production technological parameters of the original medium density fiber board need to be greatly changed, and the production efficiency is low. On the other hand, the sodium chloride and the sodium bicarbonate which are used as the flame retardant components in the patent have the problems of easiness in water absorption, moisture absorption, loss and mildew, high smoke yield, incapability of reaching B1 level of combustibility, incapability of reaching ZA3 level of smoke toxicity of the prepared flame-retardant medium density fiberboard, incapability of meeting the toxicity requirement of the medium density fiberboard and the like.

The patent CN102950632A discloses a high-efficiency environment-friendly flame retardant used for fiber boards and a preparation method thereof, and the patent has the problems that the production process of a liquid flame retardant is complex, the drying load is increased, and the liquid flame retardant volatilizes along with water vapor in the drying process, so that the effective components of the flame retardant are reduced. On the other hand, the flame retardant disclosed by the patent also has the problems that the smoke toxicity is high, the smoke toxicity of the prepared flame-retardant medium density fiberboard cannot reach ZA3 level, the standard toxicity requirement cannot be met and the like.

Therefore, the existing flame-retardant fiber boards generally have the problems of unsatisfactory flame-retardant effect, high smoke yield, incapability of meeting the ZA3 level requirement on smoke toxicity, easiness in moisture absorption, easiness in mildew and easiness in color change and the like, and the research on the flame-retardant technology and the flame retardant of the low-smoke-toxicity fiber board is urgently needed.

Disclosure of Invention

The invention aims to solve the technical problems commonly existing in the conventional flame-retardant fiber board and aims to provide a low-smoke-toxicity flame-retardant fiber board and a preparation method thereof.

A low smoke flame retardant fiberboard comprising: wood fiber and flame retardant adhesive;

the flame-retardant adhesive comprises:

resin adhesive;

a low-smoke composite flame retardant.

The water content of the wood fiber is below 7%.

The aqueous resin adhesive solution is 25 to 60%, preferably 30 to 55% by weight of the wood fiber.

The resin adhesive aqueous solution adopts at least one of a urea-formaldehyde resin adhesive aqueous solution or a melamine modified urea-formaldehyde resin adhesive aqueous solution.

The low-smoke composite flame retardant accounts for 3-30% of the weight of the wood fiber, and preferably accounts for 5-25%.

The low-smoke-toxicity composite flame retardant comprises the following raw materials:

ammonium phosphate, boric acid, borate, flame retardant synergist and smoke suppressant;

the smoke suppressant is at least one of a smoke suppressant synergist or a smoke suppressant adsorbent.

The low-smoke-toxicity composite flame retardant comprises the following raw materials in parts by weight based on 100 parts by weight of the low-smoke-toxicity composite flame retardant:

10-50 parts of ammonium phosphate salt, preferably 15-40 parts;

10-55 parts of boric acid, preferably 15-45 parts;

10-55 parts of borate, preferably 15-45 parts;

5-30 parts of flame-retardant synergist, preferably 10-28 parts;

2-30 parts of smoke suppression synergist, preferably 5-25 parts, or 1-15 parts of smoke suppression adsorbent, preferably 3-10 parts.

The ammonium phosphate is at least one of ammonium polyphosphate, ammonium monohydrogen phosphate or ammonium dihydrogen phosphate;

the borate is at least one of borax, zinc borate, calcium borate or copper borate;

the flame-retardant synergist is at least one of organic nano montmorillonite, organic silicon flame retardant, melamine cyanurate, melamine phosphate, melamine pyrophosphate, dipentaerythritol triphosphate melamine salt, dipentaerythritol phosphate melamine salt or dipentaerythritol diphosphate dihydrogen melamine salt;

the smoke suppression synergist is at least one of copper hydroxide, copper oxide, cuprous oxide, malachite, chalcopyrite, ammonium molybdate, zinc molybdate, molybdenum oxide, ferrocene, iron oxide, cadmium oxide or zinc oxide;

the smoke suppression adsorbent is at least one of a molecular sieve, graphene or aerogel.

The surface of the raw material of the low-smoke-toxicity composite flame retardant is also subjected to surface modification treatment by adopting a surface modifier.

The weight of the surface modifier is 0.1-1.5%, preferably 0.2-1.2% of the weight of the low-smoke composite flame retardant.

The surface modifier is prepared into a surface modifier solution with the concentration of 0.8-2.0 percent, preferably 1.0-1.5 percent.

The surface modifier is at least one of silane coupling agent, titanate coupling agent, aluminate coupling agent or organic silicon.

A preparation method of a low-smoke-toxicity flame-retardant fiberboard comprises the following steps:

1) weighing a resin adhesive aqueous solution, adding a low smoke toxicity composite flame retardant under stirring to prepare a flame retardant adhesive solution;

2) mixing the dried and weighed wood fibers, spraying the flame-retardant adhesive solution under the condition of stirring, continuously stirring, taking out the wood fibers, and drying;

3) paving and shaping the dried wood fiber;

4) and (3) carrying out hot-press molding on the paved and shaped wood fibers, and carrying out trimming and polishing to obtain the low-smoke-toxicity flame-retardant fiberboard.

In the step 1), the low-smoke-toxicity composite flame retardant is prepared by the following method:

101) mixing the raw materials;

102) carrying out surface modification treatment on the raw materials in a mixed state;

103) and drying the raw materials subjected to surface modification to obtain the low-smoke-toxicity composite flame retardant.

In the step 101), the raw materials are mixed in a high-speed mixer for 3 to 15min, preferably for 5 to 12min at the rotating speed of 200 to 450r/min, preferably 250 to 400 r/min;

in the step 102), a surface modifier is adopted to carry out surface modification treatment on the raw material, wherein the weight of the surface modifier is 0.1% -1.5%, preferably 0.2% -1.2% of the weight of the low-smoke-toxicity composite flame retardant, the surface modifier is prepared into a surface modifier solution with the concentration of 0.8% -2.0%, preferably 1.0% -1.5%, and the prepared surface modifier solution is completely sprayed on the surface of the raw material to realize the surface modification treatment on the raw material in the raw material mixing process;

and 103), drying the surface-modified raw materials in an oven at the temperature of 80-95 ℃ for 20-50 min, preferably 25-45 min to obtain the low-smoke-toxicity composite flame retardant.

Further comprising:

104) and crushing the low-smoke-toxicity composite flame retardant to control the granularity of the low-smoke-toxicity composite flame retardant to be more than 150 meshes, preferably more than 200 meshes.

And 104), crushing the low-smoke-toxicity composite flame retardant in a ball mill at the rotating speed of 200 r/min-450 r/min, preferably at the rotating speed of 250 r/min-400 r/min for 20 min-40 min, preferably 25 min-35 min, and controlling the particle size to be more than 150 meshes, preferably more than 200 meshes.

In the step 1), the aqueous solution of the resin adhesive is at least one of an aqueous solution of urea-formaldehyde resin adhesive with a solid content of 30-60% (preferably, 50%) or an aqueous solution of melamine modified urea-formaldehyde resin adhesive.

In the step 2), the water content of the wood fiber is below 7%, the wood fiber is placed into a high-speed mixer, the flame-retardant adhesive solution is sprayed in under the stirring condition that the rotating speed is 200 r/min-450 r/min, preferably 250 r/min-400 r/min, the mixture is continuously stirred for 5 min-20 min, preferably 8 min-15 min, the wood fiber is taken out, and the mixture is placed into an oven at 70-100 ℃, preferably 80-95 ℃ for drying for 20 min-45 min, preferably 25 min-40 min;

in the step 4), conveying the paved and shaped wood fibers into a hot-pressing forming machine;

controlling the temperature of I-V areas of the hot-pressing forming machine: the first region is 235 +/-10 ℃, the second region is 230 +/-10 ℃, the third region is 225 +/-10 ℃, the fourth region is 215 +/-10 ℃ and the fourth region is 190 +/-10 ℃;

the pressure of 5 points in the control I area is respectively as follows: 7.5 plus or minus 2MPa, 13 plus or minus 2MPa, 23 plus or minus 2MPa and 20 plus or minus 2 MPa; each pressure point lasts for 0.5-5 seconds, preferably 1-3 seconds;

the pressure of 5 points in the control II area is respectively as follows: 14.5 +/-2 MPa, 13.5 +/-2 MPa, 9.5 +/-2 MPa, 5.5 +/-2 MPa and 3.7 +/-2 MPa; each pressure point lasts for 0.5-5 seconds, preferably 1-3 seconds;

controlling the following 15 pressure points of the zone III, the zone IV and the zone V to be: 1.9 +/-1 MPa; each pressure point lasts for 0.5-5 seconds, preferably 1-3 seconds;

and finally, trimming and polishing the board subjected to hot press molding to obtain the low-smoke flame-retardant fiberboard.

The positive progress effects of the invention are as follows: the invention adopts the low-smoke-toxicity flame-retardant fiberboard and the preparation method thereof, the performance reaches GB 1-2012 'building material combustion performance grading' B1 grade, the smoke density grade SDR is less than 10, the smoke production toxicity reaches GB 20285-.

The invention adopts the low-smoke flame-retardant fiberboard which can be widely applied to indoor decoration and fitment and furniture manufacture in high-rise buildings and public places, and can effectively solve the technical problems that the prior fiberboards used in the places such as song and dance entertainment places, high smoke yield, unqualified smoke toxicity, easy mildew and easy discoloration of the fiberboards in the storage and use processes, and the like.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below.

A low-smoke-toxicity flame-retardant fiber board comprises wood fibers and a flame-retardant adhesive.

The water content of the wood fiber is 7% or less.

The flame-retardant adhesive comprises a resin adhesive and a low-smoke-toxicity composite flame retardant.

The aqueous resin adhesive solution is 25% to 60% (preferably 30% to 55%) by weight of the wood fiber. The aqueous solution of the resin adhesive is at least one of aqueous solution of urea-formaldehyde resin adhesive or aqueous solution of melamine modified urea-formaldehyde resin adhesive, and the solid content of the aqueous solution of the resin adhesive is 30-60% (preferably 50%).

The low-smoke composite flame retardant is 3-30% (preferably 5-25%) of the weight of the wood fiber. The low-smoke composite flame retardant comprises the following raw materials in parts by weight:

10-50 parts (preferably 15-40 parts) of ammonium phosphate, wherein the ammonium phosphate is at least one of ammonium polyphosphate, ammonium monohydrogen phosphate or ammonium dihydrogen phosphate. The ammonium phosphate contains phosphorus and nitrogen elements, can be decomposed to release ammonia, water vapor and other non-combustible gases in the combustion process, and can further reduce the heat value of the fiber board.

10-55 parts (preferably 15-45 parts) of boric acid. 10-55 parts (preferably 15-45 parts) of borate, wherein the borate is at least one of borax, zinc borate, calcium borate or copper borate. Boric acid and borate in the components form a glass state inorganic expansion coating in the fiber pyrolysis process, can promote carbon formation, prevent combustible materials from escaping, can dehydrate at high temperature, and has the effects of reducing heat value, foaming and diluting the combustible materials. In addition, the boric acid and the borate have the functions of corrosion prevention and bacteria prevention, and can effectively solve the problems that the fiberboard is easy to mildew and discolor.

5-30 parts (preferably 10-28 parts) of a flame-retardant synergist, wherein the flame-retardant synergist is at least one of organic nano montmorillonite, an organic silicon flame retardant, Melamine Cyanurate (MCA), melamine phosphate, melamine pyrophosphate, dipentaerythritol triphosphate melamine salt, dipentaerythritol phosphate melamine salt or dipentaerythritol diphosphate dihydrogen phosphate melamine salt. The addition of the flame-retardant synergist can further reduce the calorific value, further increase the compactness of the carbon layer and prevent the release of smoke particles and toxic gas.

2-30 parts (preferably 5-25 parts) of a smoke suppression synergist in the smoke suppression agent, wherein the smoke suppression synergist is at least one of copper hydroxide, copper oxide, cuprous oxide, malachite, chalcopyrite, ammonium molybdate, zinc molybdate, molybdenum oxide, ferrocene, iron oxide, cadmium oxide or zinc oxide. The smoke-inhibiting synergist has the function of catalyzing wood fibers to form charcoal at low temperature, can reduce the initial thermal decomposition temperature of the wood fibers, increases the coke amount generated by dehydration and carbonization at low temperature, covers the surface of a fiber board, isolates external air on one hand, inhibits further pyrolysis of the fibers, prevents granular smoke in the fibers from being released, and plays a role in inhibiting smoke.

1-15 parts (preferably 3-10 parts) of smoke suppression adsorbent in the smoke suppression agent, wherein the smoke suppression adsorbent is at least one of molecular sieve, graphene or aerogel. The smoke-suppressing adsorbent is a porous material with a very high comparative area, and can adsorb smoke particles and harmful gases generated in the combustion process, so that the smoke yield is further reduced.

The surface of the raw material of the low-smoke-toxicity composite flame retardant is subjected to surface modification treatment by adopting a surface modifier. The weight of the surface modifier is 0.1-1.5%, preferably 0.2-1.2% of the weight of the low-smoke composite flame retardant, and the surface modifier solution with the concentration of 0.8-2.0% (preferably 1.0-1.5%) is prepared. The surface modifier is at least one of silane coupling agent, titanate coupling agent, aluminate coupling agent or organic silicon. Through the surface treatment of the surface modifier, the problems of precipitation, moisture absorption and mildew of the flame retardant in the fiber board are solved.

A preparation method of a low-smoke-toxicity flame-retardant fiberboard comprises the following steps:

1) preparing a flame-retardant adhesive:

weighing the resin adhesive aqueous solution, and adding the low smoke toxicity composite flame retardant under stirring to prepare the flame-retardant adhesive solution.

In the step, at least one of a urea-formaldehyde resin adhesive aqueous solution or a melamine modified urea-formaldehyde resin adhesive aqueous solution with the weight of 25% -60% (preferably 30% -55%) of the wood fiber is weighed, and the solid content of the resin adhesive aqueous solution is 30% -60% (preferably 50%). Adding 3-30% (preferably 5-25%) of low-smoke-toxicity composite flame retardant in the weight of the wood fiber under stirring to prepare the flame-retardant adhesive solution.

The resin adhesive aqueous solution in the step is placed in a container for preparation, and the low-smoke-toxicity composite flame retardant is added into the container and stirred uniformly to prepare the flame-retardant adhesive solution.

In the step, the low smoke toxicity composite flame retardant is prepared by the following method:

101) mixing the raw materials.

The raw materials in the step are the raw materials of the low-smoke-toxicity composite flame retardant. When the raw materials are mixed, the raw materials are mixed in a high-speed mixer at the rotating speed of 200r/min to 450r/min (preferably 250r/min to 400r/min) for 3min to 15min (preferably 5min to 12 min).

102) The raw materials are subjected to surface modification treatment in a mixed state.

In the step, the surface modifier is adopted to carry out surface modification treatment on the raw material, the weight of the surface modifier is 0.1-1.5 percent, preferably 0.2-1.2 percent of the weight of the low-smoke toxic composite flame retardant, and the surface modifier solution with the concentration of 0.8-2.0 percent, preferably 1.0-1.5 percent is prepared, and in the process of mixing the raw materials, the surface modifier solution is completely sprayed on the surface of the raw material to realize the surface modification treatment on the raw material. The surface modifier is at least one of silane coupling agent, titanate coupling agent, aluminate coupling agent or organic silicon.

103) Drying the raw materials subjected to surface modification to obtain the low-smoke-toxicity composite flame retardant.

In the step, the raw material subjected to surface modification is dried in an oven at the temperature of 80-95 ℃ for 20-50 min (preferably 25-45 min) to obtain the low-smoke-toxicity composite flame retardant.

104) The low-smoke composite flame retardant is crushed, so that the granularity of the low-smoke composite flame retardant is controlled to be more than 150 meshes (preferably more than 200 meshes).

In the step, the composite flame retardant is crushed in a ball mill at the rotating speed of 200 r/min-450 r/min (preferably 250 r/min-400 r/min) for 20 min-40 min (preferably 25 min-35 min) to control the particle size to be more than 150 meshes (preferably more than 200 meshes).

2) Wood fiber flame retardant treatment:

mixing the dried and weighed wood fibers, spraying the prepared flame-retardant adhesive solution under the stirring condition, continuously stirring, taking out the wood fibers, and drying.

In the step, the water content of the wood fiber is below 7%, the wood fiber is placed into a high-speed mixer, the prepared flame-retardant adhesive solution is sprayed in the high-speed mixer under the condition that the rotation speed of the high-speed mixer is 200 r/min-450 r/min (preferably 250 r/min-400 r/min) and stirring, after the mixture is continuously stirred for 5 min-20 min (preferably 8 min-15 min), the wood fiber is taken out and is placed into an oven with the temperature of 70 ℃ -100 ℃ (preferably 80 ℃ -95 ℃) to be dried for 20 min-45 min (preferably 25 min-40 min).

3) Paving and shaping:

and paving and shaping the dried wood fiber.

In this step, the dried wood fiber can be placed into a mold frame for paving and shaping.

4) Hot-pressing and shaping:

and (3) carrying out hot-press molding on the paved and shaped wood fibers, and carrying out trimming and polishing to obtain the low-smoke-toxicity flame-retardant fiberboard.

In the step, the wood fiber which is paved and shaped is conveyed to a hot-pressing forming machine; controlling the temperature of I-V areas of the hot-pressing forming machine: the first region is 235 +/-10 ℃, the second region is 230 +/-10 ℃, the third region is 225 +/-10 ℃, the fourth region is 215 +/-10 ℃ and the fourth region is 190 +/-10 ℃; the pressure of 5 points in the control I area is respectively as follows: 7.5 plus or minus 2MPa, 13 plus or minus 2MPa, 23 plus or minus 2MPa, 20 plus or minus 2MPa, and each pressure point is 0.5-5 seconds (preferably 1-3 seconds); the pressure of 5 points in the control II area is respectively as follows: 14.5 +/-2 MPa, 13.5 +/-2 MPa, 9.5 +/-2 MPa, 5.5 +/-2 MPa and 3.7 +/-2 MPa, and each pressure point is 0.5-5 seconds (preferably 1-3 seconds); controlling the following 15 pressure points of the zone III, the zone IV and the zone V to be: 1.9 +/-1 MPa, and each pressure point is 0.5-5 seconds (preferably 1-3 seconds); and finally, trimming and polishing the board subjected to hot press molding to obtain the low-smoke flame-retardant fiberboard.

The first embodiment is as follows:

according to the raw material formulas of examples 1 to 4 and comparative examples 1 to 3 in table 1, the low smoke toxicity composite flame retardant is prepared by the following preparation method:

1. the raw materials were weighed according to the formulation and mixed in a high speed blender at 250 rpm for 5 min.

2. Preparing a surfactant solution according to the formula requirements, stirring the weighed raw materials in a high-speed mixer at 250 revolutions per minute, spraying the surfactant solution in the stirring process, and drying the raw materials subjected to surface spray modification in an oven at 90 ℃ for 25 min.

3. And (3) crushing the dried composite flame retardant in a ball mill at the rotating speed of 400 rpm for 25min to control the granularity to 200 meshes, thus obtaining the prepared low-smoke-toxicity composite flame retardants of the examples 1-4 and the comparative examples 1-3.

According to the example 5 in the table 1, the low smoke toxicity composite flame retardant is prepared by the following preparation method:

1. the raw materials were weighed according to the formulation and mixed in a high speed blender at 200 rpm for 3 min.

2. Preparing a surfactant solution according to the formula requirements, stirring the weighed raw materials in a high-speed mixer at 200 revolutions per minute, spraying the surfactant solution in the stirring process, and drying the raw materials subjected to surface spray modification in an oven at the temperature of 80 ℃ for 20 min.

3. And (3) crushing the dried composite flame retardant in a ball mill at the rotating speed of 200 rpm for 20min to control the granularity to 150 meshes, thus obtaining the prepared low-smoke-toxicity composite flame retardant of the embodiment 5.

According to example 6 in table 1, the low smoke toxicity composite flame retardant is prepared by the following preparation method:

1. the raw materials were weighed according to the recipe and mixed in a high speed mixer at 450 rpm for 15 min.

2. Preparing a surfactant solution according to the formula requirements, stirring the weighed raw materials in a high-speed mixer at 450 revolutions per minute, spraying the surfactant solution in the stirring process, and drying the raw materials subjected to surface spray modification in an oven at 95 ℃ for 50 min.

3. And (3) crushing the dried composite flame retardant in a ball mill at the rotating speed of 450 rpm for 40min to control the granularity to 200 meshes, thus obtaining the prepared low-smoke-toxicity composite flame retardant of the embodiment 6.

Table 1: raw material formula of low-smoke-toxicity composite flame retardant

The low-smoke-toxicity composite flame retardant prepared in the examples 1-4 and the comparative examples 1-3 in the table 1 is applied to the preparation process of the low-smoke-toxicity flame-retardant fiberboard, and the low-smoke-toxicity flame-retardant fiberboard is prepared according to the preparation formula in the table 2 by adopting the following preparation method:

1. drying the wood fiber until the water content is below 7%, and weighing the wood fiber with a preset weight.

2. Weighing 25-60% of resin adhesive aqueous solution by weight of wood fiber according to a preparation formula, wherein the solid content of the resin adhesive aqueous solution is 50%, and adding 5-30% of low-smoke-toxicity composite flame retardant by weight of wood fiber under stirring to prepare the flame-retardant adhesive solution.

3. And putting the dried and weighed wood fiber into a high-speed mixer, spraying the prepared flame-retardant adhesive solution under the condition of stirring at 250 revolutions per minute of the high-speed mixer, continuing to stir at high speed for 8min, taking out the wood fiber after glue spraying, and drying in an oven at 80 ℃ for 25 min.

4. And placing the wood fiber subjected to surface treatment into a mold frame for paving and shaping.

5. Conveying the paved and shaped wood fibers into a hot-pressing forming machine, and controlling the temperature of I-V areas of the hot-pressing forming machine: the temperature of the first zone is 235 ℃, the temperature of the second zone is 230 ℃, the temperature of the third zone is 225 ℃, the temperature of the fourth zone is 215 ℃ and the temperature of the fourth zone is 190 ℃. Controlling the pressure of 5 points in the I area to be 7.5MPa, 13MPa, 23MPa, 23MPa and 20MPa respectively; the pressure of 5 points in the II area is controlled to be 14.5MPa, 13.5MPa, 9.5MPa, 5.5MPa and 3.7MPa respectively, and the pressure of 15 points in the subsequent III area, IV area and V area is 1.9 MPa. The hot pressing time of each pressure point was controlled to 1 second. And finally, trimming and polishing the plate subjected to hot press forming to obtain the low-smoke-toxicity flame-retardant fiberboard of the examples 1-4 and the comparative examples 1-3.

The prepared low-smoke-toxicity composite flame retardant of example 5 is used in the preparation process of the low-smoke-toxicity flame-retardant fiberboard, and according to the preparation formula of example 4 in table 2, the low-smoke-toxicity flame-retardant fiberboard of example 4-1 is prepared by the following preparation method:

1. drying the wood fiber until the water content is below 7%, and weighing the wood fiber with a preset weight.

2. Weighing 25-60% of resin adhesive aqueous solution by weight of wood fiber according to a preparation formula, wherein the solid content of the resin adhesive aqueous solution is 30%, and adding a low-smoke-toxicity composite flame retardant by weight of 5-30% of the wood fiber under stirring to prepare a flame-retardant adhesive solution.

3. Putting the dried and weighed wood fiber into a high-speed mixer, spraying the prepared flame-retardant adhesive solution under the condition of stirring at 200 revolutions per minute of the high-speed mixer, continuing to stir at high speed for 5min, taking out the wood fiber after glue spraying, and drying in an oven at 70 ℃ for 20 min.

4. And placing the wood fiber subjected to surface treatment into a mold frame for paving and shaping.

5. Conveying the paved and shaped wood fibers into a hot-pressing forming machine, and controlling the temperature of I-V areas of the hot-pressing forming machine: the temperature of the first zone is 225 ℃, the temperature of the second zone is 220 ℃, the temperature of the third zone is 215 ℃, the temperature of the fourth zone is 205 ℃ and the temperature of the fourth zone is 180 ℃. Controlling the pressure of 5 points in the I area to be 5.5MPa, 11MPa, 21MPa, 21MPa and 18MPa respectively; the pressure of 5 points in the II area is controlled to be 13.5MPa, 11.5MPa, 7.5MPa, 3.5MPa and 1.7MPa respectively, and the pressure of 15 points in the subsequent III area, IV area and V area is 0.9 MPa. The hot pressing time of each pressure point was controlled to 0.5 seconds. And finally, trimming and polishing the plate subjected to hot press molding to obtain the low-smoke-toxicity flame-retardant fiberboard of the embodiment 5.

The prepared low-smoke-toxicity composite flame retardant of the example 6 is used in the preparation process of the low-smoke-toxicity flame-retardant fiberboard, and the low-smoke-toxicity flame-retardant fiberboard of the example 6 is prepared by the following preparation method according to the preparation formula of the example 4 in the table 2:

1. drying the wood fiber until the water content is below 7%, and weighing the wood fiber with a preset weight.

2. Weighing 25-60% of resin adhesive aqueous solution by weight of wood fiber according to a preparation formula, wherein the solid content of the resin adhesive aqueous solution is 60%, and adding a low-smoke-toxicity composite flame retardant which is 5-30% of the weight of the wood fiber under stirring to prepare a flame-retardant adhesive solution.

3. Putting the dried and weighed wood fiber into a high-speed mixer, spraying the prepared flame-retardant adhesive solution under the condition of stirring at 450 revolutions per minute of the high-speed mixer, continuing to stir at high speed for 20min, taking out the wood fiber after glue spraying, and putting the wood fiber into a 100 ℃ oven for drying for 45 min.

4. And placing the wood fiber subjected to surface treatment into a mold frame for paving and shaping.

5. Conveying the paved and shaped wood fibers into a hot-pressing forming machine, and controlling the temperature of I-V areas of the hot-pressing forming machine: the temperature of the first zone is 245 ℃, the temperature of the second zone is 240 ℃, the temperature of the third zone is 235 ℃, the temperature of the fourth zone is 225 ℃ and the temperature of the fourth zone is 200 ℃. Controlling the pressure of 5 points in the I area to be 9.5MPa, 15MPa, 25MPa, 25MPa and 22MPa respectively; the pressure of 5 points in the II area is controlled to be 16.5MPa, 15.5MPa, 11.5MPa, 7.5MPa and 5.7MPa respectively, and the pressure of 15 points in the subsequent III area, IV area and V area is 2.9 MPa. The hot pressing time of each pressure point was controlled to 5 seconds. And finally, trimming and polishing the plate subjected to hot press molding to obtain the low-smoke-toxicity flame-retardant fiberboard of the embodiment 6.

Table 2: preparation formula of low-smoke flame-retardant fiberboard

The low-smoke-toxicity composite flame retardant obtained in the above embodiments 1 to 6 and the comparative examples 1 to 3 is applied to the manufacture of the low-smoke-toxicity flame-retardant fiberboard, and the obtained low-smoke-toxicity flame-retardant fiberboard is subjected to a performance test, and the following results are shown in table 3:

table 3: performance parameters of low smoke flame-retardant fiber board

As can be seen from table 3, the low smoke toxicity flame retardant fiber boards of examples 1 to 6 prepared from the low smoke toxicity composite flame retardant of examples 1 to 6 of the invention have the combined action of smoke suppression and synergy of a plurality of flame retardant elements, and finally, the smoke density level SDR of the fiber board is lower than 10, the combustibility can reach above B1(C), the smoke toxicity can reach above ZA3, and the antibacterial, mildewproof and discoloring properties can reach the damage value 0 level requirements.

The smoke density level SDR of the plate is more than 75, the smoke toxicity is a dangerous level and the use requirement cannot be met because the smoke-inhibiting synergist and the smoke-inhibiting adsorbent are not adopted in the comparative example 1. In addition, the comparative example 1 does not adopt a surface modifier for surface modification treatment, so that the antibacterial, mildewproof and discoloring performances can only reach the damage value of 2 grades.

Since comparative example 2 does not add flame retardant synergist and smoke suppressing adsorbent, the combustion performance can only reach C grade, and the smoke toxicity is ZA3 grade.

The comparative example 3 does not adopt the flame-retardant synergist of the invention, so that the combustion performance of the plate can only reach C level.

In conclusion, under the condition of the same addition amount of the flame retardant, the flame retardant synergist is beneficial to improving the combustion performance of the board, so that the combustion performance of the board is upgraded from C level to B1 level; by adding the smoke-inhibiting synergist or the smoke-inhibiting adsorbent, the smoke-generating toxicity level SDR of the board is reduced to below 10, the smoke-generating toxicity is upgraded to above ZA3 from a dangerous level, and the toxicity standard requirement of the fiberboard is met. In addition, through the research on the surface modification treatment of the flame retardant, the antibacterial, mildew-proof and discoloring performances are upgraded to 0 grade from 2 grades of damage values, and the problems of precipitation, moisture absorption and mildew of the flame retardant are solved.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.