A kind of gypsum board and preparation method thereof

Abstract

The present disclosure provides a paper-faced gypsum board and a preparation method thereof, wherein the paper-faced gypsum board comprises a board core and a face paper, wherein the board core consists of a first density zone and a second density zone; the second density zone is located in a groove on the surface of the first density zone, and together with the first density zone, constitutes the board core; the density of the solidified material formed by the hydration of the gypsum slurry in the second density zone is greater than the solidified material formed by the hydration of the gypsum slurry in the first density zone. Compared with the existing gypsum board production, the longitudinal fracture load of the paper-faced gypsum board provided by the present application is significantly improved, and the longitudinal fracture load of the gypsum board produced by the original production process can be increased by an average of 30N.

Description

Technical Field

[0001] The present invention relates to but is not limited to the field of technical materials, and in particular to but is not limited to a gypsum board and a preparation method thereof. Background Art

[0002] At present, gypsum board is widely used in the field of decoration. The breaking load of gypsum board is the key indicator of gypsum board detection and the performance indicator of gypsum board in application. The breaking load of traditional gypsum board is mainly provided by the face paper and the gypsum board core. The face paper provides about 70% and the gypsum board core provides about 30%. The face paper is generally provided by the paper mill, and the index is relatively stable. Therefore, it is a feasible method for gypsum board manufacturers to improve the mechanical index of gypsum board and the strength of gypsum core. In the traditional gypsum board production process, gypsum is mixed with additives such as water, starch, and foaming agent in a mixer to form gypsum slurry. The gypsum slurry flows through the groove formed by the face paper to form a wet gypsum board with a certain shape, which is then cut, dried, sawed, and packaged to form a finished product. In the forming process of gypsum board, semi-hydrated gypsum is mixed with water to undergo hydration reaction to form dihydrated gypsum with a certain strength. Summary of the invention

[0003] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0004] The present disclosure provides a paper-faced gypsum board, comprising a board core and a facing paper, wherein the board core consists of a first density region and a second density region;

[0005] The second density area is located in the groove on the surface of the first density area, and together with the first density area, constitutes the board core;

[0006] The density of the solidified material formed by hydration of the gypsum slurry in the second density zone is greater than that of the solidified material formed by hydration of the gypsum slurry in the first density zone.

[0007] In one embodiment provided in the present disclosure, the ratio of the bulk density of the gypsum slurry in the second density zone to the bulk density of the gypsum slurry in the first density zone is (1.05 to 1.2):1.

[0008] In one embodiment provided in the present disclosure, when observed in a direction perpendicular to the surface of the gypsum board, the ratio of the area of ​​the groove to the area of ​​the gypsum board is 1:(1.5 to 2).

[0009] In one embodiment provided in the present disclosure, the ratio of the depth of the groove to the thickness of the gypsum board is 1:(15 to 25).

[0010] In one embodiment provided by the present disclosure, the pattern of the grooves on the surface of the first density zone is in the form of strips evenly distributed along the length direction of the gypsum board.

[0011] In one embodiment provided by the present disclosure, the gypsum slurry in the first density zone comprises: gypsum raw material slurry and a foaming agent;

[0012] In one embodiment provided by the present disclosure, the gypsum slurry in the second density zone comprises: gypsum raw material slurry, water and retarder;

[0013] In one embodiment provided in the present disclosure, the gypsum raw material slurry includes gypsum clinker, water and an admixture;

[0014] In one embodiment provided in the present disclosure, the weight ratio of the gypsum clinker to water and the admixture is (4500 to 5500):(3000 to 3500):(20 to 60).

[0015] In one embodiment provided in the present disclosure, the foaming agent is selected from any one or more of sodium lauryl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium α-olefin sulfonate and hydrogen peroxide;

[0016] In one embodiment provided in the present disclosure, the retarder is selected from any one or more of citric acid, sodium citrate, sodium hexametaphosphate, borax and protein retarders;

[0017] In one embodiment provided by the present disclosure, the admixture is selected from any one or more of a water reducing agent, starch, a lightening agent, a reinforcing agent, a porous material, a coagulant, a rubber powder and a hydraulic hydration material.

[0018] In one embodiment provided by the present disclosure, in the gypsum slurry of the second density zone, the weight ratio of the gypsum raw material slurry, the water and the retarder is (1000 to 1200): (75 to 100): (3 to 5);

[0019] In one embodiment provided in the present disclosure, the weight ratio of the gypsum raw material slurry in the first density zone to the foaming agent is (4500 to 5500):(2 to 3).

[0020] In one embodiment provided in the present disclosure, the preparation method comprises:

[0021] After the original slurry of the paper-faced gypsum board is mixed with the foaming agent, a gypsum board core is formed on the lower face paper and a groove is formed on the surface of the gypsum board core by pressing;

[0022] The original slurry of the gypsum board is drawn out to separate the slurry, and the separated slurry is mixed with the retarder and flows into the groove of the gypsum board core; and the protective paper is overlapped on the surface and adhered to form, and the gypsum board is obtained after drying.

[0023] In another aspect, the present disclosure provides a gypsum board preparation device, the device comprising:

[0024] The mixer mixes and stirs the gypsum clinker, water and an admixture to form a raw material slurry, and the mixer includes a first outlet and a second outlet;

[0025] A lead-out device, the lead-out device is configured to lead out a slurry from the raw material slurry and add a retarder and water; the inlet of the lead-out device is connected to the second outlet of the mixer; the outlet of the lead-out device spreads the slurry to which the retarder and water are added on the face paper to form a gypsum board core;

[0026] A groove pressing device, wherein the groove pressing device presses grooves on the surface of the gypsum board core;

[0027] The first outlet is configured to introduce a mixture formed by uniformly mixing the raw material slurry and the foaming agent into the groove.

[0028] In one embodiment provided in the present application, the groove pressing device is a stainless steel roller with a chrome-plated surface, which cooperates with a conveyor belt for forming the gypsum board core to form the groove.

[0029] Compared with the existing gypsum board production process, the longitudinal breaking load of the board produced by this production process is significantly improved. After drying, the longitudinal breaking load of the gypsum board produced by this production process can be increased by an average of 30N compared with the gypsum board produced by the original production process.

[0030] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by implementing the present application. Other advantages of the present application can be invented and obtained by the schemes described in the description. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present application more clear, the embodiments of the present application are described in detail below. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other arbitrarily without conflict.

[0032] The present application embodiment and comparative example are as follows: the gypsum board preparation device is used to prepare the gypsum board, and the device comprises:

[0033] A gypsum board raw material slurry storage tank, the gypsum board raw material slurry storage tank comprising a first outlet and a second outlet, the first outlet being configured to introduce a mixture 1 formed by uniformly mixing the gypsum board raw material slurry and a foaming agent into the lower face paper; the mixture 1 in the lower face paper forms a gypsum board core;

[0034] A groove pressing device, wherein the groove pressing device presses grooves on the surface of the gypsum board core;

[0035] A lead-out device is configured to lead out a slurry from the raw material slurry of the gypsum board and add at least a retarder; the inlet of the lead-out device is connected to the second outlet of the raw material slurry storage tank of the gypsum board; the outlet of the lead-out device is configured to introduce a mixture of the slurry and the slurry material mixed evenly into the groove.

[0036] Exemplarily, the groove pressing device is a stainless steel roller with a chrome-plated surface, which cooperates with a conveyor belt forming the gypsum board core to form the groove.

[0037] Example 1

[0038] This embodiment provides a gypsum board, and the preparation method of the gypsum board includes:

[0039] 1) The raw slurry of the paper-faced gypsum board forms a gypsum board core on the lower face paper and a groove for accommodating the second density zone is formed on the surface of the gypsum board core to obtain the first density zone;

[0040] 2) The original slurry of the gypsum board is drawn out from the mixer; the slurry is mixed with water and a retarder and then flows into the groove of the gypsum board core; and a face paper is overlapped on the surface of the gypsum board to form the gypsum board, and the gypsum board is obtained after drying.

[0041] The second density area is located in the groove on the surface of the first density area, and together with the first density area, constitutes the board core;

[0042] The density of the solidified material formed by hydration of the gypsum slurry in the second density zone is 6.5 g / cm 3 The density of the solidified material formed by hydration of the gypsum slurry in the first density zone is 6.0 g / cm 3 . The ratio of the bulk density of the gypsum slurry in the second density zone to the bulk density of the gypsum slurry in the first density zone is 1.08. The pattern of the grooves on the surface of the first density zone is uniformly distributed strips along the length direction of the gypsum board. The ratio of the depth of the groove to the thickness of the gypsum board is 1:20. When observed in the direction perpendicular to the surface of the gypsum board, the ratio of the area of ​​the groove to the area of ​​the gypsum board is 1:2.

[0043] The gypsum slurry in the first density zone includes: gypsum raw material slurry and foaming agent in a weight ratio of 5000:2.5. The foaming agent is sodium dodecyl sulfate purchased from BASF.

[0044] The gypsum slurry in the second density zone includes: gypsum raw material slurry, water and retarder in a weight ratio of 1000:75:5. The retarder is a protein retarder purchased from Sika Company, Plast retard L brand; the gypsum raw material slurry includes gypsum clinker, water, water reducer and modified starch, and the weight ratio is 5000:3250:25:15. The water reducer is a naphthalene-based water reducer purchased from Shenyang Puhe Chemical Co., Ltd., brand FDN-A; the moisture content in the modified starch: ≤12wt.%; pH value: 5 to 8; alkaline fluidity: 14s to 20s. The modified starch can be any one or more of modified potato starch, modified cassava starch, modified sorghum starch and modified corn starch.

[0045] Comparative Example 1

[0046] The difference between this comparative example and Example 1 is that the slurry (gypsum raw material slurry and foaming agent) in the first density zone in Example 1 is overlapped and bonded with the upper and lower facing papers to form a gypsum board after drying.

[0047] Comparative Example 2

[0048] The difference between this comparative example and Example 1 is that the slurry in the second density zone in Example 1 (gypsum raw material slurry, water and retarder) is overlapped and bonded with the upper and lower facing papers to form a gypsum board after drying.

[0049] Comparative Example 3

[0050] The only difference between this comparative example and Example 1 is that the slurry in the second density zone (gypsum raw material slurry, water and retarder) in Example 1 is interchanged with the slurry in the first density zone (gypsum raw material slurry and foaming agent), so that the density of the second density zone in the gypsum board core is lower than that of the first density zone, and the upper and lower facing papers are overlapped and adhered to form, and then dried to prepare a paper-faced gypsum board.

[0051] Example 1 and Comparative Examples 1 to 3 all produced 9.5 mm thick gypsum boards, and the size, breaking load, edge hardness, end hardness, impact resistance and adhesion of the gypsum boards were evaluated according to the Chinese national standard GB / T9755-2008. The results are shown in Table 1:

[0052] Table 1: Performance statistics of gypsum boards in embodiments and comparative examples

[0053]

Claims

1. A paper-faced gypsum board, comprising a board core and a facing paper, characterized in that: The core is composed of a first density region and a second density region; The second density area is located in the groove on the surface of the first density area, and together with the first density area, constitutes the board core; The density of the solidified material formed by hydration of the gypsum slurry in the second density zone is greater than that of the solidified material formed by hydration of the gypsum slurry in the first density zone.

2. The gypsum board according to claim 1, characterized in that: The ratio of the bulk density of the gypsum slurry in the second density zone to the bulk density of the gypsum slurry in the first density zone is (1.05 to 1.2):

1.

3. The gypsum board according to claim 1, characterized in that: When observed in a direction perpendicular to the surface of the gypsum board, the ratio of the area of ​​the groove to the area of ​​the gypsum board is 1:(1.5 to 2).

4. The gypsum board according to claim 1, characterized in that: The ratio of the depth of the groove to the thickness of the gypsum board is 1:(15 to 25).

5. The gypsum board according to any one of claims 1 to 4, characterized in that: The pattern of the grooves on the surface of the first density zone is in the form of strips evenly distributed along the length direction of the gypsum board.

6. The gypsum board according to any one of claims 1 to 4, characterized in that: The gypsum slurry in the first density zone includes: gypsum raw material slurry and a foaming agent; The gypsum slurry in the second density zone comprises: gypsum raw material slurry, water and retarder; The gypsum raw material slurry includes gypsum clinker, water and admixtures; Optionally, the weight ratio of the gypsum clinker to water and admixture is (4500 to 5500):(3000 to 3500):(20 to 60).

7. The gypsum board according to claim 6, characterized in that: The foaming agent is selected from any one or more of sodium lauryl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium α-olefin sulfonate and hydrogen peroxide; Optionally, the retarder is selected from any one or more of citric acid, sodium citrate, sodium hexametaphosphate, borax and protein retarders; Optionally, the admixture is selected from any one or more of a water reducing agent, starch, a lightening agent, a reinforcing agent, a porous material, a coagulant, a rubber powder and a hydraulic hydrating material.

8. The gypsum board according to claim 6, characterized in that: In the gypsum slurry in the second density zone, the weight ratio of the gypsum raw material slurry, the water and the retarder is (1000 to 1200): (75 to 100): (3 to 5); Optionally, the weight ratio of the gypsum raw material slurry in the first density zone to the foaming agent is (4500 to 5500):(2 to 3).

9. The method for preparing a gypsum board according to any one of claims 1 to 8, characterized in that: The preparation method comprises: After the original slurry of the paper-faced gypsum board is mixed with the foaming agent, a gypsum board core is formed on the lower face paper and a groove is formed on the surface of the gypsum board core by pressing; The original slurry of the gypsum board is drawn out to separate the slurry, and the separated slurry is mixed with the retarder and flows into the groove of the gypsum board core; and the protective paper is overlapped on the surface and adhered to form, and the gypsum board is obtained after drying.

10. A gypsum board preparation device, characterized in that: The device comprises: The mixer mixes and stirs the gypsum clinker, water and an admixture to form a raw material slurry, and the mixer includes a first outlet and a second outlet; A lead-out device, the lead-out device is configured to lead out a slurry from the raw material slurry and add a retarder and water; the inlet of the lead-out device is connected to the second outlet of the mixer; the outlet of the lead-out device spreads the slurry to which the retarder and water are added on the face paper to form a gypsum board core; A groove pressing device, wherein the groove pressing device presses grooves on the surface of the gypsum board core; The first outlet is configured to introduce a mixture formed by uniformly mixing the raw material slurry and the foaming agent into the groove.

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