WO2024060451A1

WO2024060451A1 - Lightweight flexure-resistant gypsum plasterboard and preparation method therefor

Info

Publication number: WO2024060451A1
Application number: PCT/CN2022/142538
Authority: WO
Inventors: 李帆; 杨正波; 张赫; 丛宇; 陈红霞; 张晓菲
Original assignee: 北新集团建材股份有限公司; 中建材创新科技研究院有限公司; 中国建材集团有限公司
Priority date: 2022-09-21
Filing date: 2022-12-27
Publication date: 2024-03-28

Abstract

A lightweight flexure-resistant gypsum plasterboard and a preparation method therefor. The gypsum plasterboard is prepared from the following raw materials: 100 parts by weight of calcined gypsum, 0.05-1 parts by weight of an ion retardant, 0.1-2 parts by weight of fiber, 0.15-1.5 parts by weight of a binder, 0.01-0.5 parts by weight of a foaming agent, 0.01-1 parts by weight of a crystal regulator, and 50-90 parts by weight of water.

Description

Lightweight anti-flex paper gypsum board and preparation method thereof

Technical Field

The present application relates to, but is not limited to, gypsum board preparation technology, and particularly refers to a lightweight anti-flex paper gypsum board and its preparation method.

Background technique

Industrial by-product gypsum has large emissions and low utilization rate in China. The main problem is that the quality of industrial by-product gypsum is unstable and contains a large number of impurity ions. Impurity ions not only affect the dehydration and calcination of gypsum, but also affect the performance of gypsum board. At present, 70% of gypsum boards are used for house ceilings, so the flexural resistance of the boards is an important indicator for evaluating the quality of gypsum boards. Under humid conditions, the water-soluble salts of impurity ions will absorb moisture, causing the gypsum board covering paper to be non-adherent to the core of the board. It will also cause the board to sink, directly affecting the quality of house decoration.

Summary of the invention

The following is an overview of the topics described in detail in this article. This summary is not intended to limit the scope of the application.

The embodiments of the present application provide a lightweight anti-flex paper gypsum board and its preparation method. The paper gypsum board and its preparation method can use building gypsum containing more impurity ions to prepare lightweight, good mechanical properties, and resistance to Scratched drywall.

The embodiment of the present application provides a lightweight anti-flex paper gypsum board. The raw materials for preparing the lightweight anti-flex paper gypsum board include:

In the embodiment of the present application, the crystal adjuster may be a mixture of sodium trimetaphosphate, boric acid and tartaric acid.

In the embodiment of the present application, in the crystal adjuster, based on the sodium trimetaphosphate being 1 part by weight, the boric acid may be 0.2 to 0.7 parts by weight, and the tartaric acid may be 0.1 part by weight. to 0.5 parts by weight.

In an embodiment of the present application, the ion retarder may be selected from any one or more of polyvinyl alcohol, carboxymethyl cellulose, polyacrylamide, sodium alginate and vinyl acetate-ethylene copolymer emulsion.

In the embodiment of the present application, the plaster of paris may be clinker of industrial by-product gypsum.

In the embodiment of the present application, the gypsum of paris may be any one or both of desulfurized gypsum clinker and phosphogypsum clinker.

In the embodiment of the present application, the content of CaSO ₄ ·1/2H ₂ O in the plaster of paris may be ≥60 mass%.

In the embodiment of the present application, the content of CaSO ₄ ·1/2H ₂ O in the plaster of Paris may be ≥80 mass%.

In the embodiment of the present application, the fiber may be selected from any one or both of glass fiber and polypropylene fiber.

In embodiments of the present application, the length of the fiber may range from 3 mm to 15 mm.

In embodiments of the present application, the binder may be modified starch.

In the embodiments of the present application, the binder may be selected from any one or more of modified corn starch, modified tapioca starch and pregelatinized starch.

In the embodiments of this application, the foaming agent can be selected from any one or more of sodium dodecylbenzene sulfonate, sodium fatty alcohol polyoxyethylene ether sulfate, and animal and plant protein foaming agents.

The embodiments of the present application also provide a first method for preparing the lightweight anti-flex paper gypsum board as described above. The preparation method includes:

Divide the water into a first part of water, a second part of water and a third part of water;

Mix the binder, the fiber, the crystal regulator and the first part of water to obtain a mixture;

Mix the ion blocker with the second part of water to obtain an ion blocker solution;

The foaming agent, compressed air and the third part of water are mixed and foamed to obtain a foaming solution;

Mix the plaster of paris, the mixture, the ion blocker solution and the foaming solution to obtain a slurry;

The upper and lower surfaces of the slurry are covered with protective paper, molded, and dried to obtain the lightweight anti-bending paper-faced gypsum board.

In an embodiment of the first method for preparing a lightweight flexural gypsum board of the present application, the weight ratio of the ion retardant to the second part of water may be 1:5 to 25.

In an embodiment of the first method for preparing a lightweight anti-flex paper gypsum board of the present application, the weight ratio of the foaming agent to the third part of water may be 1:30 to 100.

In the first embodiment of the preparation method of lightweight anti-flex paper gypsum board of the present application, the pressure of the compressed air may be 0.2MPa to 0.5MPa. The embodiments of the present application also provide a second method for preparing the lightweight anti-flex paper gypsum board as described above. The preparation method includes:

Mix the plaster of paris and the ion blocker to obtain a dry mixture;

mixing the binder, the fiber, the crystal modifier and a portion of water to obtain a wet mix;

The foaming agent, compressed air and remaining water are mixed and foamed to obtain a foaming solution;

Mix the dry mix, the wet mix and the foaming solution to obtain a slurry;

Attach protective paper to the upper and lower surfaces of the slurry, shape it, and dry it to obtain the lightweight anti-flex paper gypsum board.

In the second embodiment of the preparation method of lightweight anti-flex paper gypsum board of the present application, the weight ratio of the foaming agent to the water used for foaming may be 1:30 to 100.

In the second embodiment of the preparation method of lightweight anti-flex paper gypsum board of the present application, the pressure of the compressed air may be 0.2MP to 0.5MPa.

The gypsum board and its preparation method in the embodiment of the present application can effectively inhibit the migration of impurity ions in the building gypsum to the surface of the gypsum board by adding an ion retardant, thereby reducing the adverse effects of the impurity ions in the building gypsum and reducing the There are quality requirements for building gypsum raw materials, and the prepared paper-faced gypsum board has low surface density (light weight), high mechanical strength, good bonding performance between the protective paper and the board core, and good flexibility resistance of the board (moisture deflection (low), and the preparation method is simple, without significantly modifying the existing gypsum board production line.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the application. Other advantages of the present application can be realized and obtained by the solutions described in the specification.

Elaborate

In order to make the purpose, technical solutions and advantages of the present application clearer, the embodiments of the present application will be described in detail below. It should be noted that, as long as there is no conflict, the embodiments and features in the embodiments of this application can be arbitrarily combined with each other.

In the embodiment of the present application, the raw materials for preparing the lightweight anti-flex paper gypsum board can be composed of the following components:

In the embodiment of the present application, based on 100 parts by weight of the plaster of paris, the ion retardant can be 0.05 to 1 part by weight, for example, it can be 0.05, 0.1, or 0.2 parts by weight. , 0.3 parts by weight, 0.4 parts by weight, 0.5 parts by weight, 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight, 0.9 parts by weight, 1 part by weight.

In the embodiment of the present application, based on 100 parts by weight of the plaster of paris, the crystal adjuster can be 0.01 to 1 part by weight, for example, it can be 0.01 part by weight, 0.05 part by weight, 0.1 part by weight, 0.2 parts by weight, 0.3 parts by weight, 0.4 parts by weight, 0.5 parts by weight, 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight, 0.9 parts by weight, 1 part by weight.

In an embodiment of the present application, in the crystal modifier, based on 1 part by weight of the sodium trimetaphosphate, the boric acid may be 0.2 to 0.7 parts by weight, and the tartaric acid may be 0.1 to 0.5 parts by weight.

For example, based on the sodium trimetaphosphate being 1 part by weight, the boric acid can be 0.2, 0.3, 0.4, 0.5, 0.6, or 0.7 parts by weight, and the tartaric acid can be 0.1 Parts by weight, 0.2 parts by weight, 0.3 parts by weight, 0.4 parts by weight, 0.5 parts by weight.

In the embodiments of the present application, the content of CaSO ₄ ·1/2H ₂ O in the plaster of paris may be ≥ 60 mass%, for example, the content of CaSO ₄ ·1/2H ₂ O in the plaster of paris is ≥ 80 mass% .

In embodiments of the present application, the binder may be modified starch.

In an embodiment of the present application, the foaming agent can be selected from any one or more of sodium dodecylbenzene sulfonate, sodium polyoxyethylene fatty alcohol ether sulfate, and animal and plant protein foaming agents.

In the embodiment of the present application, the thickness of the lightweight anti-flex paper gypsum board may be 9.5 mm or 12 mm, etc.

It should be understood that, in addition to plaster of paris, ion retarder, fiber, binder, foaming agent, crystal adjuster and water, the raw materials for preparing the gypsum board in the embodiment of the present application may also include materials commonly used in the art. Additives for gypsum board, such as setting accelerator, water reducing agent, etc.

This application also provides the first method for preparing the lightweight anti-flex paper gypsum board as described above. The preparation method includes:

In the first embodiment of the preparation method of lightweight anti-flex paper gypsum board of the present application, the weight ratio of the ion retardant to the second part of water may be 1:5 to 25, for example, is 1:5, 1:10, 1:15, 1:20 or 1:25.

In the first embodiment of the preparation method of lightweight anti-flex paper gypsum board of the present application, the weight ratio of the foaming agent to the third part of water may be 1:30 to 100, for example, it may be 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90 or 1:100.

In the first embodiment of the preparation method of lightweight anti-flex paper gypsum board of the present application, the pressure of the compressed air can be 0.2MPa to 0.5MPa, for example, it can be 0.2MPa, 0.3MPa, 0.4MPa or 0.5MPa.

The embodiments of the present application also provide a second method for preparing the lightweight anti-flex paper gypsum board as described above. The preparation method includes:

Mix the plaster of paris and the ion blocker to obtain a dry mixture;

Mix the binder, the fiber, the crystal regulator and a part of water to obtain a wet mixture;

Mix the dry mix, the wet mix and the foaming solution to obtain a slurry;

In the second embodiment of the preparation method of lightweight anti-flex paper gypsum board of the present application, the weight ratio of the foaming agent to the water used for foaming can be 1:30 to 100, for example, it can be 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90 or 1:100.

In the second embodiment of the preparation method of lightweight anti-flex paper gypsum board of the present application, the pressure of the compressed air can be 0.2MPa to 0.5MPa, for example, it can be 0.2MPa, 0.3MPa, 0.4MPa or 0.5MPa.

The gypsum board and its preparation method in the embodiment of the present application are added by adding ion retardant (wherein, the first preparation method is to add ion retardant by wet method, and the second preparation method is to add ion retardant by dry method) , can effectively inhibit the migration of impurity ions in building gypsum to the surface of the gypsum board, thereby reducing the adverse effects of impurity ions in the building gypsum, lowering the quality requirements for building gypsum raw materials, and the surface of the prepared gypsum board Low density (lightweight), high mechanical strength, good bonding performance between the protective paper and the core of the board, good flex resistance of the board (low deflection due to moisture), and simple preparation method, no need to significantly modify the existing paper-faced gypsum board production line.

Examples and Comparative Examples

The sources of raw materials are:

Gypsum of paris: desulfurized building gypsum clinker, Beixin Building Materials (Shaanxi) Co., Ltd.;

Protective paper: Shandong Bohui Paper Co., Ltd., 180g/m ² ;

Ion blocker: polyvinyl alcohol or vinyl acetate-ethylene copolymer emulsion, Shanghai Chenqi Chemical Technology Co., Ltd.;

Polypropylene fiber: Beijing Fortern Technology Co., Ltd., length is 3mm, 9mm;

Glass fiber: China Jushi Co., Ltd., length 3mm, 15mm;

Binder: modified corn starch or pregelatinized starch, Shenyang Xuegong Adhesive Technology Co., Ltd.;

Foaming agent: sodium dodecylbenzene sulfonate, Dongming Juchen Chemical Co., Ltd.;

Foaming agent: BASF (China) Co., Ltd., brand number 812;

Sodium trimetaphosphate: Wuhan Maxin Technology Co., Ltd.;

Boric acid: Shanghai Deyi Chemical Co., Ltd.;

Tartaric acid: Shanghai Nobo Additive Co., Ltd.

The chemical analysis of desulfurized building gypsum is shown in Table 1.

Table 1 Chemical analysis of desulfurized building gypsum

The raw materials for preparing the gypsum boards of Examples 1 to 3 and Comparative Examples 1 to 9 are shown in Table 2 and Table 3 respectively.

Table 2 Raw materials for preparing the gypsum boards of Examples 1 to 3 and their amounts added

Table 3 Preparation raw materials and amounts of gypsum boards prepared in Comparative Examples 1 to 9

Note: “/” means not to add.

The preparation process of the paper-faced gypsum boards of Examples 1 to 3 and Comparative Examples 1 to 9 is:

(1) Divide the water into the first part of water, the second part of water and the third part of water;

(2) According to the raw materials and addition amounts in Table 2 and Table 3, mix the binder, fiber, crystal adjuster and the first part of water evenly to obtain Mixture A;

(3) According to the raw materials and addition amounts in Table 2 and Table 3, mix the ion blocker and the second part of water evenly to obtain an ion blocker solution;

(4) According to the raw materials and addition amounts in Table 2 and Table 3, mix the foaming agent with the third part of water and 0.2MPa to 0.5MPa compressed air before foaming to obtain a foaming solution;

(5) According to the raw materials and addition amounts in Table 2 and Table 3, add the desulfurized gypsum clinker and the ion retardant solution obtained in step (3) to the mixture A obtained in step (2) to obtain mixture B. ;

(6) Add the foaming solution obtained in step (4) to the mixture B to form a slurry containing cells; and

(7) Pour the above slurry with cells onto the lower protective paper, attach the protective paper to the upper surface of the slurry, shape it, dry at 160℃ for 30min, dry at 110℃ for 90min, and then dry at 45℃ Dry to constant weight to obtain a paper-faced gypsum board with a thickness of 9.5mm.

According to the Chinese national standard GB/T 9775-2008 "Gypsum Board", the transverse fracture load, longitudinal fracture load, gypsum board surface density, and dry adhesion of the gypsum boards prepared in the above Examples 1 to 3 and Comparative Examples 1 to 9 were tested. The bonding performance, moisture deflection, and wet-heat bonding properties that reflect the bonding performance of gypsum boards after being dampened are tested. The wet heat bonding performance test adopts the test method of cutting the gypsum board with a cross knife after steam heating. Set the water bath to 100°C. When the temperature reaches 98°C, place the gypsum board on the stand of the water bath and heat it with steam for 10 minutes. After the gypsum board is taken out of the water bath, quickly make two crisscross cuts on the gypsum board with a wallpaper knife, lift the top of the triangle and pull it upward to check the adhesion between the protective paper and the gypsum. The test results are shown in Table 4.

Table 4 Mechanical properties and bonding properties of gypsum boards of Examples 1 to 3 and Comparative Examples 1 to 9

Note: The bonding performance is divided into 5 categories, Category I: The cardboard is firmly bonded and does not separate after being lifted; Category II: A small part is separated, and most of it is intact; Category III: Half of the cardboard is firmly adhered, and half of it is separated; Category IV: Most of the cardboard is separated. , only a small part is firmly adhered; Category V: the cardboard is completely separated.

Compared with the gypsum boards of Examples 1 to 3, no ion retardant was added to the gypsum boards of Comparative Example 1 and Comparative Example 3, and the bonding performance of the gypsum boards was significantly reduced. Among the boards, the strength of gypsum board has dropped significantly, and it cannot even meet the requirements of China's national standard GB/T 9775-2008 "Gypsum Board".

Compared with the gypsum boards of Examples 1 to 3, no crystal adjuster was added to the gypsum boards of Comparative Example 1 and Comparative Example 2. The moisture deflection of the gypsum boards increased significantly, and the flexural resistance decreased significantly. It shows that the crystal adjuster can improve the flexural resistance of gypsum board.

In the gypsum board of Comparative Example 5, the boric acid was removed on the basis of Example 1. The mechanical properties and bonding properties of the gypsum board had almost no effect, indicating that the ion blocker can also inhibit building gypsum without boric acid. The impurity ions in Comparative Example 5 migrate to the surface of the gypsum board; however, the moisture deflection of the gypsum board of Comparative Example 5 is higher than that of Example 1, indicating that boric acid is helpful in improving the flexural resistance of the gypsum board.

In the gypsum board of Comparative Example 4, tartaric acid was removed on the basis of Example 3. The mechanical properties, bonding properties and flex resistance of the gypsum board were significantly reduced, indicating that in the absence of tartaric acid, other raw materials have no effect on the paper surface. The mechanical properties, bonding properties and flex resistance of gypsum boards have been adversely affected. Therefore, tartaric acid is an important admixture to improve the mechanical properties, bonding properties and flex resistance of gypsum boards.

The gypsum board of Comparative Example 6 did not add sodium trimetaphosphate, and the mechanical properties, bonding properties and flex resistance of the gypsum board were significantly lower, indicating that sodium trimetaphosphate is the key to improving the mechanical properties, adhesion and adhesion of the gypsum board. Important admixtures for bonding properties and flex resistance.

The gypsum boards of Comparative Examples 7 to 9 only add sodium trimetaphosphate, tartaric acid or boric acid, and the mechanical properties and flexural resistance of the gypsum boards are significantly lower; the gypsum boards of Comparative Example 9 only add boric acid, The wet-heat bonding performance of the gypsum board was significantly reduced compared to Example 1.

From Comparative Examples 4 to 9, it can be seen that the crystal adjuster needs to contain sodium trimetaphosphate, boric acid, and tartaric acid at the same time in order to effectively improve the flexural resistance of gypsum board. Adding only one of sodium trimetaphosphate, boric acid, and tartaric acid or Both methods cannot effectively improve the flexural resistance of gypsum board.

The raw materials for preparing the gypsum boards of Examples 4 to 6 and Comparative Examples 10 to 18 are shown in Tables 5 and 6 respectively.

Table 5 Raw materials for preparing the gypsum boards of Examples 4 to 6 and their addition amounts

Table 6 Preparation raw materials and amounts of gypsum boards prepared in Comparative Examples 10 to 18

Note: "/" means not to add.

The preparation process of the gypsum boards of Examples 4 to 6 and Comparative Examples 10 to 18 is as follows:

(1) According to the raw materials and addition amounts in Table 5 and Table 6, mix plaster of paris and ion blocker to obtain a dry mixture;

(2) According to the raw materials and addition amounts in Table 5 and Table 6, mix the binder, fiber, crystal regulator and stirring water to obtain a wet mixture;

(3) According to the raw materials and addition amounts in Table 5 and Table 6, mix the foaming agent with foaming water and 0.2MP to 0.5MPa compressed air before foaming to obtain a foaming solution;

(4) According to the raw materials and addition amounts in Table 5 and Table 6, mix the dry mixture obtained in step (1) and the wet mixture obtained in step (2) to obtain a mixture;

(5) Add the foaming solution obtained in step (3) to the mixture to form a slurry containing cells; and

(6) Pour the above slurry with cells onto the lower protective paper, attach the protective paper to the upper surface of the slurry, shape it, dry at 160℃ for 30min, dry at 110℃ for 90min, and then dry at 45℃ Dry to constant weight to obtain a paper-faced gypsum board with a thickness of 9.5mm.

According to the Chinese national standard GB/T 9775-2008 "Gypsum Board", the transverse fracture load, longitudinal fracture load, gypsum board area density, dry adhesion of the gypsum boards prepared in the above Examples 4 to 6 and Comparative Examples 10 to 18 were tested. The bonding performance, moisture deflection, and wet-heat bonding properties that reflect the bonding performance of gypsum boards after being dampened are tested. The wet heat bonding performance test adopts the test method of cutting the gypsum board with a cross knife after steam heating. Set the water bath to 100°C. When the temperature reaches 98°C, place the gypsum board on the stand of the water bath and heat it with steam for 10 minutes. After the gypsum board is taken out of the water bath, quickly make two crisscross cuts on the gypsum board with a wallpaper knife, lift the top of the triangle and pull it upward to check the adhesion between the protective paper and the gypsum. The test results are shown in Table 7.

Table 7 Mechanical properties and adhesive properties of the gypsum boards of Examples 4 to 6 and Comparative Examples 10 to 18

Compared with the gypsum boards of Examples 4 to 6, no ion retarder was added to the gypsum boards of Comparative Example 10 and Comparative Example 12, and the bonding performance of the gypsum boards was significantly reduced. Among the boards, the strength of gypsum board has dropped significantly, and it cannot even meet the requirements of China's national standard GB/T9775-2008 "Gypsum Board".

Compared with the gypsum boards of Examples 4 to 6, no crystal adjuster was added to the gypsum boards of Comparative Example 10 and Comparative Example 11. The moisture deflection of the gypsum boards increased significantly, and the flexural resistance decreased significantly. It shows that the crystal adjuster can improve the flexural resistance of gypsum board.

In the gypsum board of Comparative Example 11, the crystal adjuster was removed on the basis of Example 4. The mechanical properties of the gypsum board changed little, but the flexural resistance was significantly reduced, indicating that the crystal adjuster can improve the gypsum board's mechanical properties. Flex resistance helps.

In the gypsum board of Comparative Example 14, the boric acid was removed on the basis of Example 4. The mechanical properties and bonding properties of the gypsum board were almost not affected, and the flexural properties were reduced, indicating that ion retardation occurs in the absence of boric acid. The agent can also inhibit the migration of impurity ions in building gypsum to the surface of the gypsum board. Boric acid is helpful in improving the flexural resistance of the gypsum board.

The gypsum board of Comparative Example 13 did not add tartaric acid, and the gypsum board of Comparative Example 15 did not add sodium trimetaphosphate. The mechanical properties and flexural resistance of their gypsum boards were significantly lower, indicating that tartaric acid and trimetaphosphoric acid Sodium is an important additive for improving the mechanical properties and flexural properties of gypsum board.

The gypsum boards of Comparative Examples 16 to 18 only add sodium trimetaphosphate, tartaric acid or boric acid, and the mechanical properties and flexural properties of the gypsum boards are significantly lower; the gypsum boards of Comparative Example 18 only add boric acid. The wet-heat bonding performance of the gypsum board was significantly reduced compared to Example 4.

From Comparative Examples 13 to 18, it can be seen that the crystal adjuster needs to contain sodium trimetaphosphate, boric acid, and tartaric acid at the same time in order to effectively improve the flexural resistance of gypsum board. Adding only one of sodium trimetaphosphate, boric acid, and tartaric acid or Both methods cannot effectively improve the flexural resistance of gypsum board.

Although the embodiments disclosed in this application are as above, the contents described are only embodiments adopted to facilitate understanding of this application and are not intended to limit this application. Any technician in the field to which this application belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in this application, but the scope of protection of this application shall still be based on the scope defined in the attached claims.

Claims

A lightweight anti-flex paper-faced gypsum board, the raw materials for preparing the lightweight anti-flex paper-faced gypsum board include:
The lightweight anti-flex paper gypsum board according to claim 1, wherein the crystal adjuster is a mixture of sodium trimetaphosphate, boric acid and tartaric acid.
The lightweight anti-flex paper gypsum board according to claim 2, wherein, in the crystal adjuster, the boric acid is 0.2 to 0.7 parts by weight based on the sodium trimetaphosphate being 1 part by weight. , the tartaric acid is 0.1 to 0.5 parts by weight.
The lightweight flexural gypsum board according to any one of claims 1 to 3, wherein the ion retardant is selected from the group consisting of polyvinyl alcohol, carboxymethylcellulose, polyacrylamide, sodium alginate and Any one or more of vinyl acetate-ethylene copolymer emulsions.
The lightweight flexural resistant gypsum board according to any one of claims 1 to 4, wherein the plaster of Paris is clinker of industrial by-product gypsum.
The lightweight anti-flex paper gypsum board according to claim 5, wherein the gypsum is any one or both of desulfurized gypsum clinker and phosphogypsum clinker.
The lightweight anti-flex paper gypsum board according to claim 5 or 6, wherein the content of CaSO 4 ·1/2H 2 O in the gypsum is ≥60 mass%.
The lightweight anti-flex paper gypsum board according to claim 7, wherein the content of CaSO 4 ·1/2H 2 O in the plaster of paris is ≥80 mass%.
The lightweight flexural gypsum board according to any one of claims 1 to 8, wherein the fiber is selected from any one or both of glass fiber and polypropylene fiber.
The lightweight flexural gypsum board according to claim 9, wherein the length of the fibers ranges from 3 mm to 15 mm.
The lightweight flex-resistant gypsum board according to any one of claims 1 to 10, wherein the binder is modified starch.
The lightweight flex-resistant paper gypsum board according to claim 11, wherein the binder is selected from any one or more of modified corn starch, modified tapioca starch and pregelatinized starch.
The lightweight anti-flex paper gypsum board according to any one of claims 1 to 12, wherein the foaming agent is selected from the group consisting of sodium dodecyl benzene sulfonate, sodium fatty alcohol polyoxyethylene ether sulfate and sodium sulfate. Any one or more types of vegetable protein foaming agents.
The preparation method of lightweight anti-flex paper gypsum board according to any one of claims 1 to 13, comprising:

Divide the water into a first part of water, a second part of water and a third part of water;

Mix the binder, the fiber, the crystal regulator and the first part of water to obtain a mixture;

Mix the ion blocker with the second part of water to obtain an ion blocker solution;

The foaming agent, compressed air and the third part of water are mixed and foamed to obtain a foaming solution;

Mix the plaster of paris, the mixture, the ion blocker solution and the foaming solution to obtain a slurry;

Attach protective paper to the upper and lower surfaces of the slurry, shape it, and dry it to obtain the lightweight anti-flex paper gypsum board;

Optionally, the weight ratio of the ion blocker to the second part of water is 1:5 to 25;

Optionally, the weight ratio of the foaming agent to the third part of water is 1:30 to 100;

The pressure of the compressed air is 0.2MPa to 0.5MPa.
The preparation method of lightweight anti-flex paper gypsum board according to any one of claims 1 to 13, comprising:

Mix the plaster of paris and the ion blocker to obtain a dry mixture;

Mix the binder, the fiber, the crystal regulator and a part of water to obtain a wet mixture;

The foaming agent, compressed air and remaining water are mixed and foamed to obtain a foaming solution;

Mix the dry mix, the wet mix and the foaming solution to obtain a slurry;

Attach protective paper to the upper and lower surfaces of the slurry, shape it, and dry it to obtain the lightweight anti-flex paper gypsum board;

Optionally, the weight ratio of the foaming agent to the water used for foaming is 1:30 to 100;

The pressure of the compressed air is 0.2MP to 0.5MPa.