Gypsum-based flame-retardant plate and preparation method thereof

Abstract

The invention relates to the technical field of gypsum-based flame-retardant boards, and discloses a gypsum-based flame-retardant board and a preparation method thereof.The gypsum-based flame-retardant board comprises a gypsum base, the gypsum base is poured between surface paper and backing paper of surface protection paper, and the gypsum base is firmly bonded with the surface protection paper after being hardened; the gypsum base is prepared from the following raw materials in parts by weight: 100 parts of building gypsum powder, 1-5 parts of a fiber reinforced material, 5-20 parts of an adhesive, a flame retardant accounting for about 12%-15% of the total volume, a water reducing agent, a water repellent and a reinforcing agent of which the contents are respectively 0.1%-2%, and 60-70 parts of water. According to the gypsum-based flame-retardant board and the preparation method thereof, the building gypsum powder, the glass fibers, the adhesive, the flame retardant, the water reducing agent, the water repellent, the reinforcing agent and the water are subjected to the steps of stirring and mixing, pouring molding, drying and hardening, after-treatment and the like, the gypsum-based flame-retardant board is prepared, and the gypsum plaster board which is higher in nail-holding power and more excellent in fireproof performance is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of gypsum-based flame-retardant boards, in particular to a gypsum-based flame-retardant board and a preparation method thereof. Background Art

[0002] Gypsum-based flame-retardant board is a new type of gypsum-based high-performance fiberboard. It is a newly developed revolutionary decoration material that perfectly combines high-strength facing paper, high-strength gypsum and high-strength fiber-reinforced materials through original cementitious hard board technology.

[0003] Traditional gypsum board has low nail holding force and fire resistance. Although it can meet most usage environments, it is obviously not suitable for some occasions that require higher quality gypsum board. It is urgent for the construction industry to develop a gypsum board with higher nail holding force, better fire resistance and stability. Therefore, a gypsum-based flame retardant board and a preparation method are proposed to solve the above problems. Summary of the invention

[0004] The object of the present invention is to provide a gypsum-based flame retardant board and a preparation method thereof to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a gypsum-based flame-retardant board, comprising a gypsum base, the gypsum base is cast between the face paper and the backing paper of the face paper, the gypsum base is firmly bonded to the face paper after hardening, and the gypsum base is made of raw materials of the following components:

[0006] Building gypsum powder in an amount of 100 parts by weight;

[0007] A fiber reinforcement material in an amount of 1-5 parts by weight;

[0008] A binder in an amount of 5-20 parts by weight;

[0009] Flame retardant content of about 12%-15% of the total volume;

[0010] Water reducing agent, water repellent and reinforcing agent with contents of 0.1%-2% respectively;

[0011] Water in an amount of 60-70 parts by weight;

[0012] The fiber reinforcement material is glass fiber, and the adhesive is acrylic homopolymer or polymethyl acrylate, etc.;

[0013] By selecting high-purity and uniformly fine building gypsum powder as the base material, it can ensure that the gypsum base has good physical properties and chemical stability;

[0014] The strength and toughness of the gypsum base is enhanced by adding glass fibers with good tensile strength and weather resistance. Glass fibers are added to the gypsum base during production to improve fire resistance and thus meet Class A fire protection requirements;

[0015] By selecting high-weight, high-strength facing paper, we can ensure good bonding with the gypsum-based core material and improve the overall strength of the gypsum-based flame retardant board. The facing paper has a certain fire-retardant effect and can slow down the burning speed of the gypsum board in a fire to a certain extent.

[0016] A method for preparing a gypsum-based flame-retardant board, S1: pouring building gypsum powder, fiber reinforcement material, flame retardant, adhesive, water reducer, water repellent, reinforcing agent and water into an electric mixer, and stirring them fully until a uniform slurry is formed;

[0017] S2: pour the mixed slurry between two pre-prepared special face papers, and compact the slurry to complete the forming of the gypsum-based flame retardant board;

[0018] S3: Place the cast gypsum-based flame-retardant board in a ventilated and dry place to allow it to harden;

[0019] S4: After hardening, the gypsum-based flame retardant board is subjected to post-processing such as cutting and grinding;

[0020] S5: Check the quality of gypsum-based flame retardant boards to ensure they meet relevant standards and requirements.

[0021] Preferably, an electric mixer such as a vertical mixer, a horizontal mixer or a double-shaft mixer can be used during the stirring process, the stirring time is controlled within 1-3 minutes, and the temperature during stirring is controlled between 20° C. and 25° C.

[0022] Preferably, during the mixing process, the building gypsum powder should be poured into an electric mixer first, and then the fiber reinforcement material, flame retardant, adhesive, water reducer, water repellent, reinforcing agent and water are added, and stirred in the order of dry first and wet later. The amount of glass fiber added should not be less than 180g / ㎡, of which the short chopped glass fiber should be 6mm in length and 12-16μm in diameter, and the freshly cut glass fiber should be 9mm in length and 14-16μm in diameter. The two types of glass fibers are mixed in a 1:1 ratio.

[0023] Preferably, during the stirring process, if it is found that the water content of the building gypsum base material is too low, a proper amount of water can be added during the process. The water adding time should be controlled at the initial stage of stirring or after homogenization, and there should be a certain time interval between the two water adding times.

[0024] Preferably, before the slurry is cast and formed, the face paper is pre-treated by coating with an adhesive to improve the bonding strength with the gypsum base, and the weight of the upper and lower face papers is 210 g / ㎡.

[0025] Preferably, during the slurry casting and molding process, the slurry needs to be poured into a mold and compacted by a vibration platform to expel bubbles and improve density and surface smoothness.

[0026] Preferably, extreme temperatures should be avoided during the drying and hardening process, and the indoor temperature should be controlled between 20° C. and 25° C., and the indoor relative humidity should be controlled between 50% and 70%.

[0027] Preferably, in the post-processing process, the gypsum-based flame retardant board is cut using a gypsum board cutter, and the edge of the gypsum-based flame retardant board is grinded by an angle grinder to remove burrs, trim the shape or adjust the size.

[0028] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0029] The present invention prepares a gypsum-based flame-retardant board by mixing building gypsum powder, glass fiber, adhesive, flame retardant, water reducer, water repellent, reinforcing agent and water through the steps of stirring and mixing, casting and molding, drying and hardening, and post-processing, thereby achieving a paper-faced gypsum board with higher nail holding force and better fireproof performance. DETAILED DESCRIPTION

[0030] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0031] The present invention provides the following technical solutions:

[0032] Embodiment 1

[0033] A gypsum-based flame-retardant board comprises a gypsum base, wherein the gypsum base is cast between the face paper and the backing paper of the face paper, and the gypsum base is firmly bonded to the face paper after hardening, and the gypsum base is made of the following raw materials:

[0034] Building gypsum powder in an amount of 100 parts by weight;

[0035] A fiber reinforcement material in an amount of 1-5 parts by weight;

[0036] A binder in an amount of 5-20 parts by weight;

[0037] Flame retardant content of about 12%-15% of the total volume;

[0038] Water reducing agent, water repellent and reinforcing agent with contents of 0.1%-2% respectively;

[0039] Water in an amount of 60-70 parts by weight;

[0040] The fiber reinforcement material is glass fiber, and the adhesive is acrylic homopolymer or polymethyl acrylate, etc.;

[0041] By selecting high-purity and uniformly fine building gypsum powder as the base material, it can ensure that the gypsum base has good physical properties and chemical stability;

[0042] The strength and toughness of the gypsum base is enhanced by adding glass fibers with good tensile strength and weather resistance. Glass fibers are added to the gypsum base during production to improve fire resistance and thus meet Class A fire protection requirements;

[0043] By selecting high-weight, high-strength facing paper, we can ensure good bonding with the gypsum-based core material and improve the overall strength of the gypsum-based flame retardant board. The facing paper has a certain fire-retardant effect and can slow down the burning speed of the gypsum board in a fire to a certain extent.

[0044] Embodiment 2

[0045] A method for preparing a gypsum-based flame retardant board:

[0046] S1: Pour building gypsum powder, fiber reinforcement material, flame retardant, adhesive, water reducer, water repellent, reinforcing agent and water into an electric mixer and stir thoroughly until a uniform slurry is formed;

[0047] S2: pour the mixed slurry between two pre-prepared special face papers, and compact the slurry to complete the forming of the gypsum-based flame retardant board;

[0048] S3: Place the cast gypsum-based flame-retardant board in a ventilated and dry place to allow it to harden;

[0049] S4: After hardening, the gypsum-based flame retardant board is subjected to post-processing such as cutting and grinding;

[0050] S5: Check the quality of gypsum-based flame retardant boards to ensure they meet relevant standards and requirements.

[0051] Specifically, during the stirring process, an electric mixer such as a vertical mixer, a horizontal mixer or a double-shaft mixer can be used, the stirring time is controlled within 1-3 minutes, and the temperature during stirring is controlled between 20° C. and 25° C.

[0052] Through the above technical scheme, the temperature range between 20℃-25℃ is conducive to the full reaction of gypsum powder and water, avoiding the slowdown of gypsum hydration reaction when the temperature is too low, resulting in prolonged stirring time and uneven mixing; avoiding the gypsum base material from hardening prematurely when the temperature is too high, affecting construction performance and product quality.

[0053] Specifically, during the mixing process, the building gypsum powder should be poured into the electric mixer first, and then the fiber reinforcement material, flame retardant, adhesive, water reducer, water repellent, reinforcing agent and water should be added, and stirred in the order of dry first and then wet. The amount of glass fiber added should not be less than 180g / ㎡, of which the short glass fiber should be 6mm in length and 12-16μm in diameter, and the freshly cut glass fiber should be 9mm in length and 14-16μm in diameter. The two glass fibers should be mixed in a 1:1 ratio.

[0054] Through the above technical scheme, the order of dry first and then wet is conducive to the rapid mixing of various raw materials. The main reasons are as follows: 1. Reduce caking and agglomeration: Building gypsum powder is relatively loose in a dry state and is easy to be evenly distributed in an electric mixer. If water is added first, the building gypsum powder may form lumps or agglomerations due to the rapid action of water, resulting in uneven subsequent mixing; 2. Improve mixing efficiency: Dry first and then wet can more effectively utilize the stirring force of the electric mixer, so that the building gypsum powder is fully contacted and mixed with water and other additives, which helps to form a uniform slurry; 3. Control the reaction speed: If water is added first, the building gypsum powder will react with water quickly, resulting in premature formation of local slurry, affecting the overall mixing effect; 4. Reduce the generation of bubbles: During the mixing process, if the gypsum powder and water are not mixed evenly, bubbles may be generated, and the order of dry first and then wet helps to reduce the generation of bubbles, because the gypsum powder is mixed with water after initial dispersion, which can reduce the bubbles generated by uneven mixing.

[0055] Specifically, during the mixing process, if it is found that the water content of the building gypsum base material is too low, you can add an appropriate amount of water in the middle. The time of adding water should be controlled at the beginning of mixing or after homogenization, and there should be a certain time interval between the two additions of water.

[0056] Through the above technical scheme, adding an appropriate amount of water at the initial stage of mixing can make the building gypsum powder quickly contact with water and start to react to form a preliminary slurry, which is helpful for the initial dispersion and mixing of the building gypsum powder in the electric mixer. After the building gypsum powder reaches a homogeneous state, adding an appropriate amount of water again can further promote the uniformity of mixing. At this time, the building gypsum powder has fully contacted and reacted with water, and adding water can fill the gaps in the slurry to make the mixing more complete.

[0057] Specifically, before the slurry is cast and formed, the facing paper is pre-treated by coating with an adhesive to improve the bonding strength with the gypsum base. The weight of the upper and lower facing papers is 210g / ㎡.

[0058] Through the above technical scheme, the pretreatment steps include cleaning the face paper, drying the face paper and applying the adhesive; pretreatment of the face paper can remove impurities and moisture on the surface of the face paper, so that the adhesive can better penetrate into the paper fiber and form a stronger bond with the face paper, which is helpful to improve the overall strength and durability of the gypsum-based flame retardant board; the clean and dry face paper surface is conducive to the uniform coating and curing of the adhesive, thereby avoiding the generation of defects such as bubbles and wrinkles. This helps to improve the surface flatness of the gypsum board and improve its aesthetics; use tools such as rollers, brushes or spray guns to evenly apply adhesives such as latex, polyurethane, hot melt adhesive, etc. on the surface of the face paper, and according to the requirements of the adhesive, the necessary standing time is carried out so that the adhesive can be initially cured or form a certain viscosity, thereby enhancing the bonding force between the face paper and the gypsum-based slurry.

[0059] Specifically, during the slurry casting and molding process, the slurry needs to be poured into a mold and vibrated on a vibration platform to discharge bubbles and improve density and surface smoothness.

[0060] Through the above technical solution, high-frequency vibration is generated by the vibration platform to transfer energy to the slurry in the mold. This vibration can break the binding force between the particles in the slurry, so that the particles are rearranged and filled into a tighter space. The vibration action of the vibration platform can effectively separate the bubbles from the slurry and guide them to rise to the surface of the slurry, eventually bursting and releasing the air. During the vibration process, the surface of the slurry will be continuously impacted and squeezed by the vibration waves, making the surface smoother.

[0061] Specifically, extreme temperatures should be avoided during the drying and hardening process, the indoor temperature should be controlled between 20°C and 25°C, and the indoor relative humidity should be controlled between 50% and 70%.

[0062] Through the above technical scheme, high temperature will accelerate the hydration reaction of gypsum, resulting in too fast hardening speed, causing stress concentration and cracking problems inside the gypsum-based flame retardant board; low temperature will delay the hydration reaction of gypsum, making the hardening process slow or even unable to harden completely; 20℃-25℃ is the optimal temperature range for gypsum hydration reaction and hardening. Within this temperature range, the reaction clock of building gypsum powder and water is conducive to the formation of a dense and uniform gypsum crystal structure; an excessively high humidity environment will cause the gypsum slurry to absorb too much moisture, making the gypsum-based flame retardant board too soft and reducing its strength and hardness; controlling the indoor relative humidity between 50%-70% will help the moisture in the gypsum slurry to gradually evaporate and be evenly distributed inside the gypsum-based flame retardant board.

[0063] Specifically, in the post-processing process, a gypsum board cutter is used to cut the gypsum-based flame retardant board, and an angle grinder is used to grind the edge of the gypsum-based flame retardant board to remove burrs, trim the shape or adjust the size.

[0064] Through the above technical solution, the gypsum board cutting machine is the main equipment for cutting gypsum-based flame retardant boards. It is usually driven by electricity or pneumatic power and equipped with sharp blades or saw blades. It can accurately and quickly complete the cutting of gypsum-based flame retardant boards; the angle grinder is usually equipped with grinding wheels of different coarseness and fineness, and the appropriate grinding effect can be selected according to actual needs.

[0065] Embodiment 3

[0066] Through the second embodiment, a gypsum-based flame retardant board with a thickness of 10 mm to 15 mm can be manufactured, and various performance tests are performed on the gypsum-based flame retardant board. The test results are shown in Tables 1-5.

[0067] project Length(mm) Width(mm) Thickness(mm) Dimensional deviation -4～0 -4～0 ±0.2

[0068] Table 1 Dimensional deviation

[0069] Plate thickness (mm) Surface density (kg / ㎡) 10.0 ≤11.5 12.0 ≤14.0 15.0 ≤17.5

[0070] Table 2 Surface density

[0071]

[0072] Table 3 Fracture load

[0073] Plate thickness (mm) Shear force(N) 10.0 ≥1000 12.0 ≥1200 15.0 ≥1400

[0074] Table 4 Shear force

[0075] Plate thickness (mm) Screw holding force (N) 10.0 ≥350 12.0 ≥450 15.0 ≥700

[0076] Table 5 Screw holding force (perpendicular to the board surface)

[0077] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations may be made to the embodiments without departing from the principles and spirit thereof, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A gypsum-based flame retardant board, comprising a gypsum base, wherein the gypsum base is cast between the face paper and the backing paper of the face paper, and the gypsum base is firmly bonded to the face paper after hardening, characterized in that: The gypsum base is made of the following raw materials: Building gypsum powder in an amount of 100 parts by weight; A fiber reinforcement material in an amount of 1-5 parts by weight; A binder in an amount of 5-20 parts by weight; Flame retardant content of about 12%-15% of the total volume; Water reducing agent, water repellent and reinforcing agent with contents of 0.1%-2% respectively; Water in an amount of 60-70 parts by weight; The fiber reinforcement material is glass fiber, and the adhesive is acrylic homopolymer or polymethyl acrylate, etc.; By selecting high-purity and uniformly fine building gypsum powder as the base material, it can ensure that the gypsum base has good physical properties and chemical stability; The strength and toughness of the gypsum base is enhanced by adding glass fibers with good tensile strength and weather resistance. Glass fibers are added to the gypsum base during production to improve fire resistance and thus meet Class A fire protection requirements; By selecting high-weight, high-strength facing paper, we can ensure good bonding with the gypsum-based core material and improve the overall strength of the gypsum-based flame retardant board. The facing paper has a certain fire-retardant effect and can slow down the burning speed of the gypsum board in a fire to a certain extent.

2. The method for preparing a gypsum-based flame retardant board according to claim 1, characterized in that: S1: Pour building gypsum powder, fiber reinforcement material, flame retardant, adhesive, water reducer, water repellent, reinforcing agent and water into an electric mixer and stir thoroughly until a uniform slurry is formed; S2: pour the mixed slurry between two pre-prepared special face papers, and compact the slurry to complete the forming of the gypsum-based flame retardant board; S3: Place the cast gypsum-based flame-retardant board in a ventilated and dry place to allow it to harden; S4: After hardening, the gypsum-based flame retardant board is subjected to post-processing such as cutting and grinding; S5: Check the quality of gypsum-based flame retardant boards to ensure they meet relevant standards and requirements.

3. The method for preparing a gypsum-based flame retardant board according to claim 2, characterized in that: During the mixing process, an electric mixer such as a vertical mixer, a horizontal mixer or a double-shaft mixer can be used. The mixing time is controlled within 1-3 minutes, and the temperature during mixing is controlled between 20℃-25℃.

4. The method for preparing a gypsum-based flame retardant board according to claim 2, characterized in that: During the mixing process, the building gypsum powder should be poured into the electric mixer first, and then the fiber reinforcement material, flame retardant, adhesive, water reducer, water repellent, reinforcing agent and water should be added, and stirred in the order of dry first and then wet. The amount of glass fiber added should not be less than 180g / ㎡, of which the short-cut glass fiber should be 6mm in length and 12-16μm in diameter, and the freshly cut glass fiber should be 9mm in length and 14-16μm in diameter. The two types of glass fibers should be mixed in a 1:1 ratio.

5. The method for preparing a gypsum-based flame retardant board according to claim 2, characterized in that: During the mixing process, if you find that the water content of the building gypsum base material is too low, you can add an appropriate amount of water in the middle. The time of adding water should be controlled at the beginning of mixing or after homogenization, and there should be a certain time interval between the two additions of water.

6. The method for preparing a gypsum-based flame retardant board according to claim 2, characterized in that: Before the slurry is poured and formed, the facing paper is pre-treated by coating it with adhesive to improve the bonding strength with the gypsum base. The weight of the upper and lower facing papers is 210g / ㎡.

7. The method for preparing a gypsum-based flame retardant board according to claim 2, characterized in that: During the slurry casting process, the slurry needs to be poured into the mold and vibrated through a vibration platform to expel bubbles and improve density and surface smoothness.

8. The method for preparing a gypsum-based flame retardant board according to claim 2, characterized in that: During the drying and hardening process, extreme temperatures should be avoided, the indoor temperature should be controlled between 20℃-25℃, and the indoor relative humidity should be controlled between 50%-70%.

9. The method for preparing a gypsum-based flame retardant board according to claim 2, characterized in that: During the post-processing process, the gypsum-based flame-retardant board is cut using a gypsum board cutter, and the edge of the gypsum-based flame-retardant board is grinded by an angle grinder to remove burrs, trim the shape or adjust the size.

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