CN114274615A

CN114274615A - Aldehyde-removing paper-surface gypsum board and preparation method thereof

Info

Publication number: CN114274615A
Application number: CN202111360332.7A
Authority: CN
Inventors: 尹东杰; 谭丹君; 王鹏起; 王莹; 何亮
Original assignee: Beijing New Building Material Group Co Ltd
Current assignee: Beijing New Building Material Group Co Ltd
Priority date: 2021-11-17
Filing date: 2021-11-17
Publication date: 2022-04-05

Abstract

The application provides a clean aldehyde thistle board and a preparation method thereof, the thistle board comprises a board core and a protective paper, the board core comprises a gypsum board substrate and a clean aldehyde functional unit, the gypsum board substrate is provided with a groove, and the clean aldehyde functional unit is arranged in the groove of the gypsum board substrate to form a complete board core; the gypsum board substrate comprises the following raw materials in parts by weight: 100 parts of desulfurized gypsum clinker and 0.05 to 0.2 part of glass fiber; 0.2 to 1 part of starch; the aldehyde-purifying functional unit comprises the following raw materials in parts by weight: 100 parts of gypsum clinker, 0.5 to 5 parts of aldehyde cleaning agent, 15 to 30 parts of ordinary portland cement, 0.05 to 0.2 part of glass fiber and 0.2 to 1 part of starch.

Description

Aldehyde-removing paper-surface gypsum board and preparation method thereof

Technical Field

The invention relates to but is not limited to the field of building materials, in particular to but not limited to a formaldehyde-free paper-surface gypsum board and a preparation method thereof.

Background

The paper-surface gypsum board has the advantages of light weight, good breathing performance, good decorative performance (capable of being planed, nailed and sawed), convenient processing, environmental protection, space saving and the like, thereby being widely applied to the fields of decoration and construction of various industrial buildings and civil buildings. As a bulk building material, the paper-surface gypsum board is widely applied to interior decoration.

The formaldehyde is listed as a first class of carcinogen by the international cancer research organization, mainly comes from building decoration, finishing, coatings and the like, and is gradually and slowly released to the surrounding environment for a long time like artificial boards, finishing materials, coatings and the like used in furniture, finishing and other links, thereby forming a serious threat to the health of people and becoming a fatal killer to the health of residents. In the prior art, more and more building materials adopt an environment-friendly design to reduce formaldehyde volatilized by the building materials; the building material has low formaldehyde content, but does not have the function of adsorbing formaldehyde and purifying air.

At present, the aldehyde-cleaning gypsum board mainly realizes the aldehyde-cleaning function by doping an adsorption substance or spraying a photocatalyst material. The formaldehyde content can be reduced in a short time by simple adsorption, but the problem of secondary release of a pollution source after saturated adsorption exists, so that the formaldehyde-purifying gypsum plasterboard developed by the application aims to solve the problem that formaldehyde is released to the air again after saturated adsorption in the gypsum plasterboard and is harmful to human health.

Disclosure of Invention

The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the present application.

The application provides a thistle board, the thistle board includes board core and mask paper, the board core includes the gypsum board base member and clean aldehyde functional unit, the gypsum board base member is provided with the recess, clean aldehyde functional unit sets up in the recess of the gypsum board base member, forms complete the board core;

in one embodiment provided by the present application, the number of the grooves may be one or more than two;

the gypsum board substrate comprises the following raw materials in parts by weight: 100 parts of desulfurized gypsum clinker and 0.05 to 0.2 part of glass fiber; 0.2 to 1 part of starch;

in one embodiment provided herein, the raw materials of the gypsum board matrix further comprise a retarder and a water reducing agent, optionally, the retarder is 0.15 to 0.8 parts by weight, the water reducing agent is 0.05 to 0.2 parts by weight, and the amount of water can be 55 to 70 parts by weight, based on 100 parts by weight of the gypsum clinker;

the aldehyde-purifying functional unit comprises the following raw materials in parts by weight: 100 parts of gypsum clinker, 0.5 to 5 parts of aldehyde cleaning agent, 15 to 30 parts of ordinary portland cement, 0.05 to 0.2 part of glass fiber and 0.2 to 1 part of starch, wherein the using amount of water can be 50 to 80 parts, and preferably 60 to 80 parts.

In one embodiment provided herein, the raw materials of the clean aldehyde functional unit further include a retarder and a water reducing agent, optionally, the amount of the foaming agent is 0.5 to 5 parts by weight and the amount of the water reducing agent is 0.2 to 1 part by weight based on 100 parts by weight of the gypsum clinker.

In one embodiment provided herein, the groove is centrally located on a surface of the gypsum board substrate;

in one embodiment provided herein, the depth of the grooves is 1/3 to 1/2 of the thickness of the paper-faced gypsum board; optionally, the length of the groove is 1/3 to 2/3 of the length of the gypsum plasterboard, optionally the width of the groove is equal to the width of the gypsum plasterboard.

In this applicationIn one embodiment provided, the gypsum clinker has a chloride ion content of no greater than 400 mg/kg. The specific surface area of the gypsum clinker can be 3500cm²G to 4000cm²/g。

In one embodiment provided herein, the starch is a modified starch, optionally the starch has a viscosity of from 1000 mPa-s to 5000 mPa-s.

In one embodiment provided herein, the glass fiber may be any one or more of a medium alkali glass fiber, an alkali-free glass fiber and an alkali-resistant glass fiber, the glass fiber has a fiber length of 9mm to 15mm, and the glass fiber has a filament diameter of 10 μm to 15 μm.

In one embodiment provided herein, the retarder is selected from any one or more of citric acid, sodium citrate, sodium hexametaphosphate, borax, and protein-based retarders;

in one embodiment provided herein, the protein retarder is selected from one or two of a bone collagen protein retarder and a protein gypsum retarder in which degraded polyamide is calcium-modified.

In one embodiment provided herein, the water reducing agent is selected from any one or more of a naphthalene based superplasticizer, an aliphatic water reducing agent, a polycarboxylic acid based superplasticizer, and an aminosulfonic acid based superplasticizer.

In one embodiment provided herein, the portland cement has a strength rating of any one or more of 42.5, 42.5R, 52.5, and 52.5R.

In one embodiment provided herein, the foaming agent is selected from any one or more of basf 812, basf Vinapor DF 9010F, and basf ALS-70.

In one embodiment provided herein, the aldehyde cleaning agent can be any one or more of tetrapod-like zinc oxide whiskers, titanium dioxide, zinc oxide, tin oxide, and cadmium sulfide.

In another aspect, the present application provides a method for preparing the above paper-surface gypsum board, comprising the following steps:

the method comprises the following steps: preparing a gypsum board substrate, adding the retarder, the water reducer and the starch into water, and fully mixing and stirring to obtain a mixed solution; uniformly mixing the glass fiber and the gypsum clinker to obtain a dry mixture; uniformly mixing and stirring the dry mixture and the mixed solution to prepare gypsum slurry;

step two: preparing a clean aldehyde functional unit, and uniformly mixing the glass fiber, the gypsum clinker and the ordinary portland cement to prepare a mixture 1; adding the starch, the water reducing agent, the aldehyde purifying agent and a part of foaming agent into water, and uniformly stirring to obtain a mixture 2; uniformly mixing the mixture 2, the mixture 1 and the rest foaming agent to prepare pure aldehyde functional unit slurry;

step three: arranging a baffle plate to distinguish the positions of the aldehyde-purifying functional units and the gypsum matrix in the board core, pouring gypsum slurry on the lower protective paper, pouring aldehyde-purifying functional unit slurry after pouring, drawing out the baffle plate, connecting the slurry at the joint into a whole to form an unhydrated gypsum board core, overlapping and firmly bonding the upper protective paper and the unhydrated gypsum board core to form a wet paper-surface gypsum board, and drying the wet board to obtain the paper-surface gypsum board;

in one embodiment provided by the present application, in step three, the wet board is solidified on the conveyor belt, cut, and then enters a dryer, and after three drying stages of 180 ℃, 110 ℃ and 45 ℃, the dried board is laminated, edge sawed, edge sealed, and packaged to form the gypsum plaster board.

In one embodiment provided herein, in step three, the pouring of the neat aldehyde functional unit slurry is completed before the initial setting of the gypsum slurry.

In an embodiment provided by the application, in the third step, gypsum slurry is poured on the lower protective paper, and after pouring, aldehyde functional unit slurry and the gypsum slurry prepared in the first step are poured.

In one embodiment, the present application provides a gypsum plasterboard produced by the above-described production method.

The application provides a thistle board can adsorb and decompose formaldehyde, has solved the adsorption material and has adsorbed secondary release problem after the formaldehyde saturation, from the root in the clean room formaldehyde.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the application. Other advantages of the present application may be realized and attained by the invention in its aspects as described in the specification.

Drawings

The accompanying drawings are included to provide an understanding of the present disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the examples serve to explain the principles of the disclosure and not to limit the disclosure.

FIG. 1 is a schematic representation of a neat aldehyde gypsum board made in accordance with an embodiment of the present disclosure, where B is the neat aldehyde unit and A is the gypsum board matrix.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, embodiments of the present application are described in detail below. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

In the following examples and comparative examples, the desulfurized gypsum clinker used was made of desulfurized gypsum which is a solid waste produced by flue gas desulfurization in power plants;

the glass fiber is purchased from alkali glass fiber of mineral products Limited of Jinghang in Hebei, the fiber length is 10mm, and the fiber monofilament diameter is 10 μm;

the foaming agent is purchased from chemical company of Jinnzhao, Ji;

the modified starch is purchased from Jinan Yuan chemical Co., Ltd; viscosity is 3500 mPa.s; the method for measuring the viscosity of the starch adopts a test method in the China chemical industry standard HG/T3932-2007, the concentration of a sample is 5%, the temperature is 25 ℃, the rotor number is 3, and the rotating speed is 6 r/min;

the retarder is a protein gypsum retarder formed by calcium calcification of degraded polyamide, and is purchased from Qinit 2000, Italy, Western Retard PE, Shanghai Qin and chemical engineering Co., Ltd;

the water reducing agent is purchased from Tianjin Lanhao science and technology limited and is a polycarboxylate water reducing agent, and the type is as follows: a basf water reducer, PLUS 312;

the foaming agent is purchased from Tianjin Lanhao science and technology limited and is a basf 812 foaming agent;

the aldehyde cleaning agent is purchased from Otsugaku Dajingyu technologies, Inc., and is tetrapod-like zinc oxide whisker;

the ordinary portland cement is 42.5 strength grade ordinary portland cement;

example 1

The method for preparing the paper-surface gypsum board comprises the following specific steps:

the method comprises the following steps: preparation of Gypsum Board substrate (part A)

Weighing raw materials: weighing 100 parts by weight of desulfurized gypsum clinker, 59 parts by weight of water, 0.06 part by weight of glass fiber, 0.65 part by weight of retarder, 0.18 part by weight of water reducing agent and 0.28 part by weight of starch; adding the retarder, the water reducing agent and the starch into water, and fully mixing and stirring; uniformly mixing the glass fiber and the desulfurized gypsum clinker; the dry materials are added into the mixed solution, and the gypsum slurry is prepared by uniformly mixing and stirring.

Step two: preparation of neat aldehyde functional units (part B)

Weighing raw materials: 100 parts of desulfurized gypsum clinker, 18 parts of ordinary portland cement, 2.7 parts of foaming agent, 57 parts of water, 0.08 part of glass fiber, 0.3 part of starch, 0.85 part of water reducing agent and 0.8 part of formaldehyde purifying agent.

The preparation method of the clean aldehyde functional unit comprises the following steps: 1. uniformly mixing the glass fiber with the desulfurized gypsum clinker and the ordinary portland cement; 2. adding starch, a water reducing agent, an aldehyde purifying agent and 50% of a foaming agent into water, and uniformly stirring; 3. and (3) adding the mixture prepared in the step (1) and 50% of foaming agent into the mixed solution prepared in the step (2), and continuously mixing and uniformly stirring to prepare the aldehyde-purifying functional unit slurry.

Step three: the formaldehyde-free gypsum board is prepared by two-layer pouring, wherein the upper layer is poured by three sections.

Lower layer 8 mm: the gypsum slurry which is uniformly stirred is thrown into the lower protective paper on the forming table under the action of centrifugal force, and the gypsum slurry is smooth in vibration.

Upper layer 4 mm: set up the baffle between clean aldehyde functional unit and gypsum slurry, pour gypsum slurry earlier, pour clean aldehyde functional unit slurry again, pour after, take out the baffle, the ground paste interconnect of seam department becomes an organic whole, forms left and right three-layer structure (gypsum slurry + clean aldehyde functional unit slurry + gypsum slurry) in the upper strata.

And finishing the pouring of the upper layer before the initial setting of the gypsum slurry of the lower layer. Gypsum ground paste that pours on the upper strata forms groove structure together with the gypsum ground paste of lower floor, and groove structure is inside for net aldehyde functional unit ground paste, and groove structure is located gypsum board core intermediate position, along gypsum board middle part symmetric distribution, and length is the two-thirds of gypsum board length, and with the equal width of gypsum board, thickness is the third of gypsum board thickness. The left, middle and right sections of the upper layer are 1/6, 2/3 and 1/6 of the length of the gypsum board.

Step four: after the lower protective paper is folded into a right angle along the roller mark, the lower protective paper and the slurry are overlapped with the upper protective paper under the extrusion of the forming plate and are firmly adhered to form a wet plate, and then the wet plate is led out under the traction of a solidification belt to finish the forming.

And step five, solidifying the wet plate on a conveying belt, cutting the wet plate, and then entering a dryer to be dried at the temperature of 180 ℃, 110 ℃ and 45 ℃.

Step six: and (4) combining the dried boards, sawing edges, sealing edges and packaging to form the gypsum plaster board.

Example 2

Weighing raw materials: weighing 100 parts by weight of desulfurized gypsum clinker, 66 parts by weight of water, 0.20 part by weight of glass fiber, 0.20 part by weight of retarder, 0.08 part by weight of water reducer and 0.5 part by weight of starch; adding the retarder, the water reducing agent and the starch into water, and fully mixing and stirring; uniformly mixing the glass fiber and the desulfurized gypsum clinker; the dry materials are added into the mixed solution, and the gypsum slurry is prepared by uniformly mixing and stirring.

Step two: preparation of neat aldehyde functional units (part B)

Weighing raw materials: 100 parts of desulfurized gypsum clinker, 25 parts of ordinary portland cement, 0.6 part of foaming agent, 75 parts of water, 0.15 part of glass fiber, 1 part of starch, 0.28 part of water reducing agent and 4.5 parts of formaldehyde purifying agent.

The lower layer is 6 mm: the gypsum slurry which is uniformly stirred is thrown into the lower protective paper on the forming table under the action of centrifugal force, and the gypsum slurry is smooth in vibration.

Upper layer 6 mm: set up the baffle between clean aldehyde functional unit and gypsum slurry, pour gypsum slurry earlier, pour clean aldehyde functional unit slurry again, pour after, take out the baffle, the ground paste interconnect of seam department becomes an organic whole and forms left and right three-layer structure (gypsum slurry + clean aldehyde functional unit slurry + gypsum slurry) in the upper layer.

And finishing the pouring of the upper layer before the initial setting of the gypsum slurry of the lower layer. Gypsum ground paste that pours on the upper strata forms groove structure together with the gypsum ground paste of lower floor, and groove structure is inside for net aldehyde functional unit ground paste, and groove structure is located gypsum core intermediate position, prolongs gypsum board middle part symmetric distribution, and length is the two-thirds of gypsum board length, and with the equal width of gypsum board, thickness is the half of gypsum board thickness. The left, middle and right sections of the upper layer are 1/6, 2/3 and 1/6 of the length of the gypsum board.

The steps four to six are the same as in example 1.

Comparative example 1

This comparative example differs from example 1 in that the gypsum slurry prepared in step one is used to prepare a paper-faced gypsum board without the inclusion of a formaldehyde scavenger.

Comparative example 2

This comparative example differs from example 1 only in that only neat aldehyde unit slurry is used to make paper-faced gypsum board.

Comparative example 3

The comparative example differs from real-time example 1 only in that the neat aldehyde units do not involve glass fibers. Other raw materials and preparation processes are completely the same as those of example 1.

Comparative example 4

This comparative example differs from example 1 only in that no portland cement is added. Other raw materials and preparation processes are completely the same as those of example 1.

Test example 1

The physical and mechanical properties of the gypsum plasterboard are detected by referring to the Chinese national standard GB/T9775-2008 'gypsum plasterboard', and the test results of the gypsum plasterboard in the examples and the comparative examples are shown in Table 1.

TABLE 1 mechanical Properties test results of thistle boards

According to the test results in table 1, the mechanical properties of the gypsum plasterboards prepared in example 1, example 2 and comparative example 2 can meet the national standard requirements, and are higher than those of the commercially available common gypsum boards in comparative example 1. The gypsum boards prepared in comparative examples 3 and 4 can not meet the national standard requirements and are far lower than those prepared in example 1, which shows that the glass fibers in the net aldehyde units and the gypsum base plate are mutually overlapped and cooperate with the silicate cement to jointly improve the mechanical strength of the gypsum boards.

Test example 2

Refer to the China building materials industry standard JCT-1074-. The results of the testing of the example and comparative paper-faced gypsum boards are shown in table 2.

TABLE 2 cleaning Performance test results for gypsum plasterboards

According to the test results in table 2, the clean aldehyde effect of the embodiment 1 and the embodiment 2 is excellent, and the formaldehyde purification rate reaches over 90 percent, which is much higher than that of the common gypsum board sold on the market of the comparative example 1. In addition, the purification effect of the plate prepared by only using the pure aldehyde unit slurry meets the standard requirement, but the purification effect is not as good as that of the plate prepared by the embodiment 1 and the embodiment 2. The data of comparative example 3 and comparative example 4 show that glass fiber and ordinary portland cement are required to be added into the formaldehyde purifying unit to realize synergistic interaction with the gypsum substrate, so that the overall formaldehyde purification performance of the board is improved.

Test example 3

The Chinese national standard GB50325 building code standard stipulates that the formaldehyde concentration of a class of buildings (including residential buildings, apartments, offices, kindergartens, geriatrics and the like) is less than 0.08mg/m³. This test example tests the neat aldehyde rate of the panels.

The test method comprises the following steps: cutting gypsum board with size of 20mm by 20mm, and placing in 30cm³In the environmental chamber, 3 μ L of formaldehyde solution with a concentration of 1% is dripped into the chamber, and the change of the formaldehyde concentration in the environmental chamber is monitored.

Experimental results show that the aldehyde-purifying functional unit B, the cement, the gypsum slurry and the aldehyde-purifying agent act synergistically: the two are used in a combined way, so that the concentration peak value of formaldehyde in the environmental bin is obviously reduced; the formaldehyde content is reduced to 0.08mg/m³The purification time is shortened by more than 70 percent. The two have synergistic effect, and can achieve the purposes of quickly removing formaldehyde and obviously improving the purification efficiency.

TABLE 2 clean aldehyde Rate test results for thistle boards

As can be seen from tables 1, 2, and 3, the gypsum plasterboard prepared in the examples of the present application can satisfy the national standard requirements in terms of mechanical properties, and has better purification performance than commercially available formaldehyde-free gypsum plasterboards.

Although the embodiments disclosed in the present application are described above, the descriptions are only for the convenience of understanding the present application, and are not intended to limit the present application. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the disclosure as defined by the appended claims.

Claims

1. A thistle board comprises a board core and a protective paper, wherein the board core comprises a gypsum board substrate and a formaldehyde purification functional unit, the gypsum board substrate is provided with a groove, and the formaldehyde purification functional unit is arranged in the groove of the gypsum board substrate to form a complete board core;

optionally, the raw materials of the gypsum board substrate further comprise a retarder and a water reducing agent, wherein the retarder is 0.15 to 0.8 part by weight and the water reducing agent is 0.05 to 0.2 part by weight based on 100 parts by weight of the gypsum clinker;

the aldehyde-purifying functional unit comprises the following raw materials in parts by weight: 100 parts of gypsum clinker, 0.5 to 5 parts of aldehyde cleaning agent, 15 to 30 parts of ordinary portland cement, 0.05 to 0.2 part of glass fiber and 0.2 to 1 part of starch,

optionally, the raw materials of the clean aldehyde functional unit further comprise a retarder and a water reducing agent, and optionally, the amount of the foaming agent is 0.5 to 5 parts by weight and the amount of the water reducing agent is 0.2 to 1 part by weight based on 100 parts by weight of the gypsum clinker.

2. A paper-faced gypsum board as set forth in claim 1, wherein said groove is centrally disposed on the surface of the gypsum board base;

optionally, the depth of the groove accounts for 1/3 to 1/2 of the thickness of the paper gypsum board; optionally, the length of the groove is 1/3 to 2/3 of the length of the gypsum plasterboard, optionally the width of the groove is equal to the width of the gypsum plasterboard.

3. The paper-faced gypsum board of claim 1 or 2, wherein the starch is a modified starch, optionally the starch has a viscosity of from 1000 mPa-s to 5000 mPa-s;

optionally, the glass fiber is selected from any one or more of medium alkali glass fiber, alkali-free glass fiber and alkali-resistant glass fiber, optionally, the fiber length of the glass fiber is 9mm to 15mm, and the monofilament diameter of the glass fiber is 10 μm to 15 μm.

4. The paper-faced gypsum board of claim 1 or 2, wherein the set retarder is selected from any one or more of citric acid, sodium citrate, sodium hexametaphosphate, borax, and protein-based set retarders;

optionally, the protein retarder is selected from one or two of a bone glue protein retarder and a protein gypsum retarder formed by calcium-calcified degraded polyamide.

5. The paper-faced gypsum board according to claim 1 or 2, wherein the water reducing agent is selected from any one or more of a naphthalene-based high-efficiency water reducing agent, an aliphatic water reducing agent, a polycarboxylic acid-based water reducing agent, and an aminosulfonic acid-based water reducing agent.

6. The gypsum plasterboard of claim 1 or 2, wherein the strength grade of the ordinary portland cement is selected from any one or more of 42.5, 42.5R, 52.5 and 52.5R;

optionally, the foaming agent is selected from any one or more of basf 812, basf Vinapor DF 9010F, and basf ALS-70.

7. A paper-faced gypsum board according to claim 1 or 2, wherein the aldehyde-scavenging agent may be any one or more of tetrapod-like zinc oxide whiskers, titanium dioxide, zinc oxide, tin oxide and cadmium sulfide.

8. A method of making a paper-faced gypsum board according to any one of claims 1 to 7, comprising the steps of:

step three: arranging a baffle plate to distinguish the positions of the aldehyde-purifying functional units and the gypsum matrix in the board core, pouring gypsum slurry on the lower protective paper, pouring aldehyde-purifying functional unit slurry after pouring, completely pouring, drawing out the baffle plate, connecting the slurry at the joint into a whole to form an unhydrated gypsum board core, lap-jointing and firmly bonding the upper protective paper and the unhydrated gypsum board core to form a wet paper gypsum board, and drying the wet board to obtain the paper gypsum board.

9. The method of making a paper-faced gypsum board as claimed in claim 8, wherein, in step three, the casting of the neat aldehyde functional unit slurry is completed before the initial setting of the gypsum slurry.

10. The method for preparing a paper-surface gypsum board according to claim 8 or 9, wherein in the third step, gypsum slurry is poured on the lower face paper, and the aldehyde functional unit slurry and the gypsum slurry prepared in the first step are poured after pouring.