Foaming agent mixed liquor, gypsum slurry, gypsum board and method for preparing gypsum slurry and gypsum board
By using foam stabilizer to adjust the foaming agent mixture during the preparation process of gypsum board, the problems of uneven distribution of pore diameters and high water absorption in gypsum board are solved, and a more uniform pore size and the effect of reducing water absorption is achieved.
Patent Information
- Application Number
- CN202311436972.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-10-31
- Publication Date
- 2024-12-24
AI Technical Summary
The diameter of the pores in existing gypsum boards is unevenly distributed, resulting in insufficient performance and high water absorption.
Using a foaming agent mixture containing unstable foaming agent and foam stabilizer, the pore diameter distribution is controlled by adjusting the proportion of foam stabilizer, and combined with calcined gypsum, starch, water reducing agent, coagulation accelerator and retarder, prepare The gypsum slurry formed by uniform pores has a gypsum board core with a pore diameter deviation value of no more than 1.2 and a water absorption rate of no more than 25%.
The pore size in the gypsum board is achieved more uniformly, and the pore size distribution is controlled, which reduces the water absorption rate of the gypsum board and improves performance.
Smart Images
Figure CN119176689A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of building materials, in particular to a foaming agent mixed liquid for making gypsum boards, a gypsum-based slurry containing the foaming agent mixed liquid, and a gypsum board formed by the slurry. Background Art
[0002] Gypsum board is a common building board at present. Generally, gypsum board is composed of a board core formed by gypsum slurry and a face paper attached to the board core. Gypsum slurry is formed by mixing calcined gypsum, water and additives.
[0003] In order to reduce the weight of the gypsum board, a foaming agent is usually added to the gypsum slurry to form bubbles in the slurry. In this way, the formed board core has a large number of pores, thereby reducing the weight of the gypsum board.
[0004] However, since the formation of bubbles is uncontrolled, the resulting pores in the core have a wide distribution range in diameter. The goal of the industry is to form pores with uniform distribution and diameter in the core. Summary of the invention
[0005] To this end, the object of the present invention is to improve the diameter distribution of pores in the core of a gypsum board, thereby improving the performance of the gypsum board.
[0006] According to one aspect of the present invention, a foaming agent mixture comprises an unstable foaming agent and a foam stabilizer, wherein the foam stabilizer accounts for 3-50% of the total mass of the foaming agent mixture, and wherein the foam stabilizer is a sodium alpha olefin sulfonate solution.
[0007] According to another aspect of the present invention, a gypsum slurry comprises the following components by mass: 100 parts of calcined gypsum, 0.2-5 parts of starch, and 0.03-0.20 parts of the aforementioned foaming agent mixture.
[0008] Furthermore, the gypsum slurry also includes: 0.1-0.5 parts of water reducing agent, 0.1-1 parts of setting accelerator, 0.1-1 parts of setting retarder, and 50-70 parts of water.
[0009] According to another aspect of the present invention, a gypsum board comprises a core formed from the above gypsum slurry, wherein the core has pores, wherein the deviation value of the pore diameter does not exceed 1.2, preferably does not exceed 1.0. Furthermore, the water absorption rate of the core does not exceed 25%.
[0010] According to another aspect of the present invention, a method for preparing the aforementioned gypsum slurry comprises the following steps: step 100, adding the foam stabilizer solution to an unstable foaming agent solution to form a foaming agent mixed liquid; step 200, mixing the foaming agent mixed liquid with water, and injecting gas for foaming to form a second mixed liquid; step 300, mixing the second mixed liquid with calcined gypsum, water, starch, a water reducer, a setting accelerator and a setting retarder to uniformly stir.
[0011] According to another aspect of the present invention, a method for preparing the aforementioned gypsum board comprises the following steps: step 10, providing a first protective layer; step 20, placing the gypsum slurry on the first protective layer to form a slurry layer, wherein the gypsum slurry is prepared by the aforementioned method for preparing the aforementioned gypsum slurry; step 30, providing a second protective layer on the slurry layer to form a wet board body; step 40, drying the wet board body. Further comprising: forming a primer layer on the side of the first protective layer and / or the second protective layer facing the slurry.
[0012] The technical solution provided by the present invention makes the pore size in the formed gypsum board more uniform and can control the size distribution of the pores to a certain extent. The technical solution of the present invention also reduces the water absorption rate of the formed gypsum board. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 This is a picture of the core of a gypsum board obtained using an existing foaming agent solution.
[0014] Figure 2 This is a picture of the core of the gypsum board of Example 10.
[0015] Figure 3 This is a picture of the core of the gypsum board of Example 6. DETAILED DESCRIPTION
[0016] The specific embodiments of the present invention are described in detail below, wherein the disclosed details are only used to illustrate the present invention but not to limit the present invention.
[0017] According to one embodiment of the present invention, a foaming agent mixed liquid includes an unstable foaming agent and a foam stabilizer. The unstable foaming agent can be any suitable existing product and can be obtained from the market through commercial channels.
[0018] The foam stabilizer is a sodium alpha olefin sulfonate solution, such as an aqueous solution, which can be obtained through commercial channels. Based on different products, the concentration range of sodium alpha olefin sulfonate is usually 30-35% by mass.
[0019] The foam stabilizer accounts for 3-50% of the total mass of the foaming agent mixture, and the specific proportion depends on the concentration of the sodium alpha olefin sulfonate solution and the diameter of the pores in the desired final product.
[0020] The inventors of the present application have found that when other process parameters remain unchanged, the proportion of foam stabilizer is negatively correlated with the diameter of the pores in the final gypsum board core. That is, the higher the proportion of foam stabilizer, the smaller the diameter of the umbilicus of the final gypsum board core. When the proportion of foam stabilizer exceeds 50%, the pores in the gypsum board core are too small and cannot effectively reduce the weight of the gypsum board. When the proportion of foam stabilizer is less than 3%, the final gypsum board core may have defects. Therefore, compared with not using foam stabilizer, the technical solution of the present application can reduce pore defects in gypsum board, such as fusion or connection of multiple pores.
[0021] According to another embodiment of the present invention, a gypsum slurry includes the following components by mass: 100 parts of calcined gypsum, 0.2-5 parts of starch, 0.03-0.20 parts of the aforementioned foaming agent mixture, 0.1-0.5 parts of a water reducing agent, 0.1-1 parts of a setting accelerator, 0.1-1 parts of a setting retarder and 50-70 parts of water.
[0022] The dosage of the foaming agent mixture can be determined according to the specific application. When the foaming agent mixture is low, the bubble wall becomes thinner and breaks due to the decrease in foaming agent, resulting in less air remaining in the slurry and reducing the foaming efficiency. When the foaming agent mixture becomes high, the bubbles are stable and have a small diameter, but too much foaming agent cannot further improve the foaming efficiency. The foaming efficiency mentioned here refers to the density ratio of gypsum slurry to water. The lower the density ratio, the higher the foaming efficiency. Compared with the existing foaming agent, the foam stabilizer added to the foaming agent mixture of the present application can increase the foaming efficiency by about 5%.
[0023] The water reducing agent, coagulant and retarder can be any suitable existing product available through commercial channels, and their specific dosage can be determined by those skilled in the art according to actual conditions. In the present invention, the dosage range of the water reducing agent, coagulant, water and retarder is the commonly used range in the art.
[0024] According to another embodiment of the present invention, a gypsum board comprises a board core formed of the aforementioned gypsum slurry, wherein the board core has pores, wherein the deviation value of the pore diameter does not exceed 1.2, preferably does not exceed 1.0.
[0025] The method for measuring the deviation value of the pore diameter is as follows.
[0026] To obtain a picture of the cross section of the board core, any suitable camera device may be used to obtain the picture of the board core.
[0027] The diameter and area of the pores in the image are identified by software, which can be obtained through commercial channels. Among them, the pore diameters D10, D50 and D90 are determined. The D10 is the pore diameter corresponding to the pore diameter distribution number reaching 10%, and its physical meaning is that the pores with a diameter less than D10 account for 10%. Similarly, D50 is the pore diameter corresponding to the pore diameter distribution number reaching 50%, and its physical meaning is that the number of pores with a diameter less than D50 accounts for 50%, and the number of pores greater than D50 also accounts for 50%. D90 is the pore diameter corresponding to the pore diameter distribution number reaching 50%, and its physical meaning is that the number of pores with a diameter less than D90 accounts for 90%. In other words, D50 is the middle value of the pore diameter distribution.
[0028] The deviation value, also called the span SPAN, is obtained using the following formula 1.
[0029] SPAN=(D90-D10) / D50 Formula 1
[0030] The smaller the deviation value obtained, that is, the closer the span is to 0, the more uniform the pores are and the higher the size consistency is.
[0031] Furthermore, due to the use of the foam stabilizer, more closed pores are generated, so the water absorption rate of the core of the board is reduced. According to the method specified in the "GB / T9775-2008 National Standard for Gypsum Board", the core water absorption rate of the gypsum board of the present invention does not exceed 25%.
[0032] The gypsum board may also include a protective layer, which is attached to the board core to form a laminated structure. Furthermore, a primer layer may be provided between the protective layer and the board core. The primer layer may be formed by gypsum slurry without a foaming agent.
[0033] According to another embodiment of the present invention, a method for preparing the aforementioned gypsum slurry comprises the following steps.
[0034] Step 100, adding the foam stabilizer solution to the unstable foaming agent solution to form a foaming agent mixed solution.
[0035] Step 200, the foaming agent mixture is mixed with water, and gas is injected for foaming to form a second mixture. Foaming is usually performed using a dedicated device, and the gas used is usually air. Generally, the size of bubbles in the soap solution can be controlled by adjusting the amount of air, the amount of foaming agent, and the speed of the foaming machine.
[0036] Step 300, mixing the second mixed liquid with calcined gypsum, water, starch, water reducing agent, setting accelerator and setting retarder and stirring them uniformly.
[0037] The method for preparing a gypsum board using the above gypsum slurry comprises the following steps: step 10, providing a first protective layer; step 20, placing the gypsum slurry on the first protective layer to form a slurry layer, wherein the gypsum slurry is prepared by the above method for preparing the above gypsum slurry; step 30, providing a second protective layer on the slurry layer to form a wet board body; step 40, drying the wet board body. The method further comprises: forming a primer layer on the side of the first protective layer and / or the second protective layer facing the slurry.
[0038] The following are specific examples of multiple gypsum boards, wherein the gypsum slurry is prepared according to the following components: 100 parts of calcined gypsum, 0.5 parts of starch, 0.1 parts of foaming agent mixture, 0.5 parts of water reducer, 0.3 parts of coagulant, 0.5 parts of retarder, and 55 parts of water. The foaming agent mixture is prepared according to Table 1.
[0039] Table 1
[0040] Unstable foaming agent solution (wt.%) Foam stabilizer solution (wt.%) Deviation value Example 1 50 50 1.13 Example 2 55 45 0.88 Example 3 60 40 0.94 Example 4 64 36 0.96 Example 5 69 31 1.01 Example 6 75 25 0.92 Example 7 78 22 1.02 Example 8 79 21 0.86 Example 9 80 20 1.10 Example 10 86 14 1.07 Example 11 87 13 0.80 Example 12 88 12 1.01 Example 13 89 11 1.10 Example 14 90 10 0.98 Example 15 91 9 1.12 Example 16 93 7 1.10 Example 17 94 6 1.07 Example 18 97 3 1.16
[0041] As shown in Table 1, the deviation values of the pore diameters of the core of the gypsum board are all less than 1.2, preferably less than 1.0.
[0042] Reference Figure 2 and 3 , which correspond to the core images of the gypsum boards of Examples 10 and 6, respectively. It can be seen that when the content of the foam stabilizer solution increases, the pore diameter of the core becomes smaller. Moreover, compared with the existing foaming agent solution, the core of the gypsum board obtained according to the technical solution of the present invention has more closed pores, so it can reduce the water absorption rate.
[0043] In the above description, the details of the technical solution of the present invention are explained. However, those skilled in the art can understand that the present invention is not limited to the specific details listed in the above embodiments, but can be changed within the scope defined by the claims.
Claims
1. A foaming agent mixture, comprising an unstable foaming agent and a foam stabilizer, wherein the foam stabilizer accounts for 3-50% of the total mass of the foaming agent mixture.
2. The foaming agent mixed solution according to claim 1, characterized in that: The foam stabilizer is sodium alpha olefin sulfonate solution.
3. A gypsum slurry comprising the following components by mass: 100 parts of calcined gypsum, 0.2-5 parts of starch, and 0.03-0.20 parts of the foaming agent mixture as described in claim 1 or 2.
4. The gypsum slurry according to claim 3, characterized in that The gypsum slurry also includes: 0.1-0.5 parts of water reducing agent, 0.1-1 parts of setting accelerator, 0.1-1 parts of setting retarder, and 50-70 parts of water.
5. A gypsum board comprising a board core formed by the gypsum slurry according to claim 3 or 4, wherein the board core has pores, characterized in that: The deviation of pore diameter shall not exceed 1.
2.
6. The gypsum board according to claim 5, characterized in that The deviation value of the pore diameter does not exceed 1.
0.
7. The gypsum board according to claim 5, characterized in that The water absorption rate of the board core does not exceed 25%.
8. A method for preparing the gypsum slurry according to any one of claims 3 or 4, comprising the following steps: Step 100, adding the foam stabilizer solution to the unstable foaming agent solution to form a foaming agent mixed solution; Step 200, mixing the foaming agent mixed liquid with water, and injecting gas for foaming to form a second mixed liquid; Step 300, mixing the second mixed liquid with calcined gypsum, water, starch, water reducing agent, setting accelerator and setting retarder and stirring them uniformly.
9. A method for producing the gypsum board according to any one of claims 5 to 7 using the gypsum slurry prepared by the method according to claim 8, comprising the following steps: Step 10, providing a first protective layer; Step 20, placing the gypsum slurry on the first facing layer to form a slurry layer; Step 30, providing a second facing layer on the slurry layer to form a wet board body; Step 40, drying the wet plate body.
10. The method according to claim 9, characterized in that Further including: A primer layer is formed on a side of the first armour layer and / or the second armour layer facing the slurry.