Moisture-proof and pressure-resistant hollow plate material containing waste ceramic gypsum and preparation method thereof

Abstract

This invention discloses a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum and its preparation method, belonging to the field of plastic board technology. This invention fully utilizes gypsum waste and substandard ceramics, significantly reducing raw material costs while minimizing the accumulation of industrial solid waste and environmental pollution. Gypsum and ceramic powder, as high-strength, low-cost rigid inorganic fillers, enhance the compressive strength and dimensional stability of the board. Simultaneously, by utilizing the lightweight properties of gypsum-based materials and the cost advantages of the two waste materials, product weight and production costs are effectively controlled. Furthermore, the high-temperature resistance of gypsum and ceramics synergistically improves flame-retardant properties, achieving high-value recycling of waste resources. Pretreatment of the gypsum-ceramic powder significantly improves the material's moisture-proof and pressure-resistant properties.

Description

Technical Field

[0001] This invention relates to the field of plastic sheet technology, specifically to a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum and its preparation method. Background Technology

[0002] With the rapid development of industries such as construction and packaging, the demand for lightweight, high-strength, and environmentally friendly building materials is increasing. Hollow core boards, as a lightweight and high-strength composite material, are widely used in building partitions, decorative panels, and logistics packaging due to their excellent mechanical properties and designability. However, traditional hollow core board materials (such as pure polypropylene hollow core boards) suffer from insufficient mechanical strength, easy deformation, and poor flame retardancy; while gypsum-based boards, although possessing advantages such as low cost and good fire resistance, suffer from defects such as high brittleness and poor water resistance, severely limiting their application range.

[0003] Ceramics and gypsum are common materials in industrial production, generating a large amount of waste and substandard products each year. Ceramic waste has high hardness and good chemical stability, but it is difficult to biodegrade naturally; while gypsum waste can be partially recycled, its recycling value is low. Currently, most of these wastes are disposed of through landfill, which not only occupies land resources but also may cause environmental pollution. How to achieve high-value utilization of these solid wastes has become an important issue in the fields of environmental protection and resource recycling.

[0004] In the prior art, Chinese patent CN112358681A discloses a method for preparing low-cost, high-strength PP hollow boards, which uses recycled refractory bricks as fillers and adds a small amount of nano-silicon nitride as a strength modifier. Although this method realizes the utilization of waste refractory materials, the compatibility between waste refractory materials and plastic matrices is poor, which easily leads to weak interfacial bonding. Moreover, the fillers used are limited to refractory materials and do not involve ceramic-gypsum composite systems.

[0005] However, when hollow core board technology uses waste ceramics and gypsum as fillers, gypsum, being a hydrophilic material, allows moisture to seep into the hollow core board in humid environments. This creates uneven stress within the board, easily leading to warping, delamination, and other problems, affecting the structural integrity of the hollow core board. Therefore, developing a hollow core board material that can utilize both ceramic and gypsum waste while possessing excellent moisture resistance and compressive strength has significant technological innovation value and practical application significance. Summary of the Invention

[0006] The main objective of this invention is to propose a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum and its preparation method.

[0007] To achieve the above objectives, this invention proposes a method for preparing a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum, comprising the following steps:

[0008] S1. Collect gypsum waste and substandard ceramic products, mix them, and then grind them to obtain gypsum ceramic powder;

[0009] S2. Pre-treat the gypsum ceramic powder to obtain pre-treated gypsum ceramic powder;

[0010] S3. Mix the pretreated gypsum ceramic powder, polypropylene resin, borax, dispersant, and plasticizer evenly to obtain a mixture;

[0011] S4. The mixture is heated to a molten state and then extruded, cooled, drawn, and cut to obtain a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum.

[0012] Preferably, the mass ratio of gypsum waste to defective ceramic products in step S1 is 1:1-2.

[0013] Preferably, in step S2, the mass ratio of pretreated gypsum ceramic powder, polypropylene resin, borax, dispersant, and plasticizer is 30-40:80-100:10-20:1-5:1-5.

[0014] Preferably, the specific steps of step S2 are as follows:

[0015] (1) Disperse gypsum ceramic powder in an ethanol aqueous solution, add 3-mercaptopropyltrimethoxysilane, stir to react, filter to collect the solid, wash and dry to obtain mercapto-based gypsum ceramic powder;

[0016] (2) Disperse mercapto-based gypsum ceramic powder in N,N-dimethylformamide, add p-trifluoromethylcinnamaldehyde and photoinitiator, react under ultraviolet irradiation, collect the solid product, wash and dry to obtain hydrophobic modified gypsum ceramic powder;

[0017] (3) Add hydrophobically modified gypsum ceramic powder to dimethyl sulfoxide, add terminal amino-terminated nitrile rubber, heat to react, filter to collect solids, wash and dry to obtain pretreated gypsum ceramic powder.

[0018] Preferably, in step (1), the mass ratio of gypsum ceramic powder to 3-mercaptopropyltrimethoxysilane is 20-30:3-5; the stirring reaction temperature is 30-50℃, and the reaction time is 3-5h.

[0019] In this step, surface treatment of gypsum ceramic powder with 3-mercaptopropyltrimethoxysilane can introduce thiol groups onto the surface of the gypsum ceramic powder, which is beneficial for subsequent reactions and can also improve the compatibility between gypsum ceramic powder and resin matrix.

[0020] Preferably, in step (2), the mass ratio of mercapto-phosphorus gypsum ceramic powder, p-trifluoromethylcinnamaldehyde, and photoinitiator is 30:4-7:0.1-0.3; the photoinitiator is at least one of benzoin dimethyl ether, 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone, 2-isopropylthioxanthone, 1-hydroxycyclohexylphenyl ketone, methyl benzoylformate, alkyl thioonium salt, alkyl iodoonium salt, aryl iodoonium salt, and aryl thioonium salt.

[0021] In this step, the thiol group of the thiol-based gypsum ceramic powder undergoes a thiol-alkene click reaction with the carbon-carbon double bond on p-trifluoromethylcinnamaldehyde, thereby introducing p-trifluoromethylcinnamaldehyde into the gypsum ceramic powder and introducing hydrophobic fluorocarbon chains and aldehyde groups.

[0022] Preferably, in step (3), the mass ratio of hydrophobic modified gypsum ceramic powder to amine-terminated nitrile rubber is 10:2.5-3.5; the heating reaction temperature is 40-60℃ and the reaction time is 4-8h.

[0023] In this step, the aldehyde groups on the hydrophobically modified gypsum ceramic powder react with the terminal amine-butadiene acrylonitrile rubber to introduce the terminal amine-butadiene acrylonitrile rubber onto the gypsum ceramic powder, thereby obtaining pretreated gypsum ceramic powder.

[0024] Preferably, the dispersant in step S3 is at least one of ethylene bis-stearamide, polyethylene wax, polypropylene wax, and paraffin wax.

[0025] Preferably, the plasticizer in step S3 is at least one of tributyl citrate, epoxidized soybean oil, dioctyl sebacate, trimethylolpropane, and triacetin.

[0026] Preferably, the heating temperature in step S4 is 190-210℃.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0028] (1) This invention provides a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum and its preparation method. This invention makes full use of gypsum waste and ceramic defects, significantly reducing raw material costs, while reducing the accumulation of industrial solid waste and environmental pollution. Gypsum and ceramic powder, as high-strength and low-cost rigid inorganic fillers, can enhance the compressive strength and dimensional stability of the board. At the same time, by utilizing the lightweight characteristics of gypsum-based materials and the cost advantages of the two wastes, the weight of the product and production costs are effectively controlled. Furthermore, the high-temperature resistance of gypsum and ceramic can synergistically improve the flame retardant performance, realizing the high-value recycling of waste resources.

[0029] (2) By pretreating gypsum ceramic powder, the present invention can significantly improve the moisture resistance and mechanical properties of the material. First, by grafting fluorocarbon chains and aldehyde groups, the fluorocarbon chains have extremely low surface energy. When they are oriented on the material surface, they can form a superhydrophobic interface and produce a water-repellent property similar to the "lotus effect", which improves the hydrophobicity of the material. Second, by introducing flexible terminal amino-terminated nitrile rubber molecular chains, a "flexible buffer layer" is constructed between the rigid inorganic powder and the polypropylene matrix. This buffer layer not only greatly improves the interfacial bonding force between the two, but also effectively absorbs and dissipates impact energy when the material is under stress, significantly improving the compressive strength and impact toughness of the composite material and overcoming the brittleness problem caused by traditional filler materials. At the same time, the rubber molecular chains themselves have good hydrophobicity. They can fill and cover the small hydrophilic defects on the surface of the inorganic powder and work together with the fluorocarbon chains to build a rigid and flexible composite waterproof barrier, ensuring that the material maintains excellent dimensional stability and mechanical properties in a long-term humid environment.

[0030] (3) The moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum of the present invention has high strength, excellent moisture-proof performance and significant cost advantages. It can be widely used in building partitions, decorative substrates and packaging and transportation fields where load-bearing requirements are not high. As an economical and environmentally friendly alternative to some traditional boards, this technology provides a new idea for the efficient recycling of waste ceramics and gypsum, and has significant environmental benefits and economic value. Detailed Implementation

[0031] To avoid unnecessary details, unless otherwise specified, all items used in the following examples are commercially available products, and all methods used are conventional methods unless otherwise specified.

[0032] The sources of some of the raw materials used in this invention are as follows:

[0033] Polypropylene resin, LG Chem, South Korea, brand name GP-1000FC, purchased from Suzhou Boyihui Plastics Co., Ltd. Example 1

[0034] A method for preparing a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum includes the following steps:

[0035] S1. Collect 100g of gypsum waste and 150g of substandard ceramics, mix them, grind them, and pass them through a 100-mesh sieve to obtain gypsum ceramic powder;

[0036] S2. Disperse 50g of gypsum ceramic powder in 300mL of 50wt% ethanol aqueous solution, add 8.2g of 3-mercaptopropyltrimethoxysilane, stir and react at 40℃ for 4h, filter, collect the solid, wash and dry to obtain mercapto-based gypsum ceramic powder.

[0037] S3. Disperse 30g of mercapto-based gypsum ceramic powder in 200mL of N,N-dimethylformamide, add 5.6g of p-trifluoromethylcinnamaldehyde and 0.2g of benzoin dimethyl ether, at a strength of 95μW / cm 2 The reaction was carried out under ultraviolet light for 2 hours, and the solid product was collected, washed and dried to obtain hydrophobic modified gypsum ceramic powder.

[0038] S4. Add 20g of hydrophobic modified gypsum ceramic powder to 200mL of dimethyl sulfoxide, add 6g of terminal amino-terminated nitrile rubber, heat and react at 50℃ for 6h, filter, collect the solid, wash and dry to obtain pretreated gypsum ceramic powder.

[0039] S5. Mix 35.8g of pretreated gypsum ceramic powder, 90g of polypropylene resin, 16.2g of borax, 2.4g of polypropylene wax, and 2.5g of tributyl citrate evenly to obtain a mixture.

[0040] S6. The mixture is heated to a molten state at 200℃ and then extruded, cooled, drawn, and cut to obtain a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum. Example 2

[0041] A method for preparing a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum includes the following steps:

[0042] S1. Collect 100g of gypsum waste and 100g of substandard ceramics, mix them, grind them, and pass them through a 100-mesh sieve to obtain gypsum ceramic powder;

[0043] S2. Disperse 50g of gypsum ceramic powder in 300mL of 50wt% ethanol aqueous solution, add 7.5g of 3-mercaptopropyltrimethoxysilane, stir and react at 30℃ for 5h, filter, collect the solid, wash and dry to obtain mercapto-based gypsum ceramic powder.

[0044] S3. Disperse 30g of mercapto-based gypsum ceramic powder in 200mL of N,N-dimethylformamide, add 4g of p-trifluoromethylcinnamaldehyde and 0.1g of benzoin dimethyl ether, at a strength of 95μW / cm 2 The reaction was carried out under ultraviolet light for 2 hours, and the solid product was collected, washed and dried to obtain hydrophobic modified gypsum ceramic powder.

[0045] S4. Add 20g of hydrophobic modified gypsum ceramic powder to 200mL of dimethyl sulfoxide, add 6g of terminal amino-terminated nitrile rubber, heat and react at 40℃ for 8h, filter, collect the solid, wash and dry to obtain pretreated gypsum ceramic powder.

[0046] S5. Mix 30g of pretreated gypsum ceramic powder, 80g of polypropylene resin, 10g of borax, 1g of polypropylene wax and 1g of epoxidized soybean oil evenly to obtain a mixture.

[0047] S6. The mixture is heated to a molten state at 190℃ and then extruded, cooled, drawn, and cut to obtain a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum. Example 3

[0048] A method for preparing a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum includes the following steps:

[0049] S1. Collect 100g of gypsum waste and 200g of substandard ceramics, mix them, grind them, and pass them through a 100-mesh sieve to obtain gypsum ceramic powder;

[0050] S2. Disperse 50g of gypsum ceramic powder in 300mL of 50wt% ethanol aqueous solution, add 8.3g of 3-mercaptopropyltrimethoxysilane, stir and react at 50℃ for 3h, filter, collect the solid, wash and dry to obtain mercapto-based gypsum ceramic powder.

[0051] S3. Disperse 30g of mercapto-based gypsum ceramic powder in 200mL of N,N-dimethylformamide, add 7g of p-trifluoromethylcinnamaldehyde and 0.3g of benzoin dimethyl ether, at a strength of 95μW / cm 2 The reaction was carried out under ultraviolet light for 2 hours, and the solid product was collected, washed and dried to obtain hydrophobic modified gypsum ceramic powder.

[0052] S4. Add 20g of hydrophobic modified gypsum ceramic powder to 200mL of dimethyl sulfoxide, add 5g of terminal amino-terminated nitrile rubber, heat and react at 60℃ for 4h, filter, collect the solid, wash and dry to obtain pretreated gypsum ceramic powder.

[0053] S5. Mix 40g of pretreated gypsum ceramic powder, 100g of polypropylene resin, 20g of borax, 5g of polypropylene wax and 5g of epoxidized soybean oil evenly to obtain a mixture.

[0054] S6. The mixture is heated to a molten state at 210℃ and then extruded, cooled, drawn, and cut to obtain a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum. Comparative Example 1

[0055] A method for preparing a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum is similar to that in Example 1, except that terminal amine-terminated nitrile rubber is not added during the preparation of the pretreated gypsum ceramic powder. The method specifically includes the following steps:

[0056] S1. Collect 100g of gypsum waste and 150g of substandard ceramics, mix them, grind them, and pass them through a 100-mesh sieve to obtain gypsum ceramic powder;

[0057] S2. Disperse 50g of gypsum ceramic powder in 300mL of 50wt% ethanol aqueous solution, add 8.2g of 3-mercaptopropyltrimethoxysilane, stir and react at 40℃ for 4h, filter, collect the solid, wash and dry to obtain mercapto-based gypsum ceramic powder.

[0058] S3. Disperse 30g of mercapto-based gypsum ceramic powder in 200mL of N,N-dimethylformamide, add 5.6g of p-trifluoromethylcinnamaldehyde and 0.2g of benzoin dimethyl ether, at a strength of 95μW / cm 2 The reaction was carried out under ultraviolet light for 2 hours, and the solid product was collected, washed and dried to obtain pretreated gypsum ceramic powder.

[0059] S4. Mix 35.8g of pretreated gypsum ceramic powder, 90g of polypropylene resin, 16.2g of borax, 2.4g of polypropylene wax, and 2.5g of tributyl citrate evenly to obtain a mixture.

[0060] S5. The mixture is heated to a molten state at 200℃ and then extruded, cooled, drawn, and cut to obtain a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum. Comparative Example 2

[0061] A method for preparing a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum is similar to that in Example 1, except that the trifluoromethylcinnamaldehyde is physically mixed during the preparation of the pretreated gypsum ceramic powder, and includes the following steps:

[0062] S1. Collect 100g of gypsum waste and 150g of substandard ceramics, mix them, grind them, and pass them through a 100-mesh sieve to obtain gypsum ceramic powder;

[0063] S2. Disperse 50g of gypsum ceramic powder in 300mL of 50wt% ethanol aqueous solution, add 8.2g of 3-mercaptopropyltrimethoxysilane, stir and react at 40℃ for 4h, filter, collect the solid, wash and dry to obtain mercapto-based gypsum ceramic powder.

[0064] S3. Mix 30g of mercapto-based gypsum ceramic powder and 5.6g of p-trifluoromethylcinnamaldehyde evenly to obtain pretreated gypsum ceramic powder;

[0065] S4. Mix 35.8g of pretreated gypsum ceramic powder, 90g of polypropylene resin, 16.2g of borax, 2.4g of polypropylene wax, and 2.5g of tributyl citrate evenly to obtain a mixture.

[0066] S5. The mixture is heated to a molten state at 200℃ and then extruded, cooled, drawn, and cut to obtain a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum. Comparative Example 3

[0067] A method for preparing a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum is similar to that in Example 1, except that p-trifluoromethyl cinnamaldehyde and terminal amino-butadiene nitrile rubber are not added during the preparation of the pretreated gypsum ceramic powder. The method includes the following steps:

[0068] S1. Collect 100g of gypsum waste and 150g of substandard ceramics, mix them, grind them, and pass them through a 100-mesh sieve to obtain gypsum ceramic powder;

[0069] S2. Disperse 50g of gypsum ceramic powder in 300mL of 50wt% ethanol aqueous solution, add 8.2g of 3-mercaptopropyltrimethoxysilane, stir and react at 40℃ for 4h, filter, collect the solid, wash and dry to obtain pretreated gypsum ceramic powder.

[0070] S5. Mix 35.8g of pretreated gypsum ceramic powder, 90g of polypropylene resin, 16.2g of borax, 2.4g of polypropylene wax, and 2.5g of tributyl citrate evenly to obtain a mixture.

[0071] S6. The mixture is heated to a molten state at 200℃ and then extruded, cooled, drawn, and cut to obtain a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum.

[0072] Performance testing

[0073] The test subjects were the moisture-proof and compression-resistant hollow board materials containing waste ceramic gypsum prepared in Examples 1-3 and Comparative Examples 1-3. The test contents are as follows:

[0074] Water absorption thickness swelling rate: determined in accordance with GB / T 17657-2022 "Standard for Test Methods of Physical and Chemical Properties of Wood-based Panels and Decorative Wood-based Panels";

[0075] Compression resistance: Take the sample to be tested, place it at room temperature for 24 hours, then place it vertically on the pressure testing machine and apply pressure at a speed of 100 mm / min. The pressure that first rises to the maximum value on the load curve is the compression resistance value of the sample to be tested. The average value of 5 test results is recorded as the final result.

[0076] Tensile properties: Dumbbell-shaped specimens (Type 1A) were prepared according to standard GB / T 1040.2-2022 "Determination of tensile properties of plastics - Part 2: Test conditions for molded and extruded plastics". Tensile strength tests were then conducted according to standard GB / T 1040.1-2018 "Determination of tensile properties of plastics - Part 1: General". The test speed was 1 mm / min, and the average of five test results was recorded as the final result. The test results are shown in Table 1.

[0077] Table 1. Test results of moisture-proof and compression-resistant hollow board material containing waste ceramic gypsum.

[0078]

[0079] As can be seen from the experimental results in Table 1, the moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum obtained by the present invention has good moisture-proof and pressure-resistant properties.

[0080] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the patent protection scope of the present invention.

Claims

1. A method for preparing a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum, characterized in that, Includes the following steps: S1. Collect gypsum waste and substandard ceramic products, mix them, and then grind them to obtain gypsum ceramic powder; S2. Pre-treat the gypsum ceramic powder to obtain pre-treated gypsum ceramic powder; S3. Mix the pretreated gypsum ceramic powder, polypropylene resin, borax, dispersant, and plasticizer evenly to obtain a mixture; S4. The mixture is heated to a molten state and then extruded, cooled, drawn, and cut to obtain a moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum. The specific steps of step S2 are as follows: (1) Disperse gypsum ceramic powder in an ethanol aqueous solution, add 3-mercaptopropyltrimethoxysilane, stir to react, filter to collect the solid, wash and dry to obtain mercapto-based gypsum ceramic powder; (2) Disperse mercapto-based gypsum ceramic powder in N,N-dimethylformamide, add p-trifluoromethylcinnamaldehyde and photoinitiator, react under ultraviolet irradiation, collect the solid product, wash and dry to obtain hydrophobic modified gypsum ceramic powder; (3) Add hydrophobically modified gypsum ceramic powder to dimethyl sulfoxide, add terminal amino-terminated nitrile rubber, heat to react, filter to collect solids, wash and dry to obtain pretreated gypsum ceramic powder.

2. The preparation method according to claim 1, characterized in that: In step S1, the mass ratio of gypsum waste to defective ceramic products is 1:1-2.

3. The preparation method according to claim 1, characterized in that: In step S2, the mass ratio of pretreated gypsum ceramic powder, polypropylene resin, borax, dispersant, and plasticizer is 30-40:80-100:10-20:1-5:1-5.

4. The preparation method according to claim 1, characterized in that: In step (1), the mass ratio of gypsum ceramic powder to 3-mercaptopropyltrimethoxysilane is 20-30:3-5.

5. The preparation method according to claim 1, characterized in that: In step (2), the mass ratio of mercapto-paraffin ceramic powder, p-trifluoromethylcinnamaldehyde, and photoinitiator is 30:4-7:0.1-0.

3.

6. The preparation method according to claim 1, characterized in that: In step (3), the mass ratio of hydrophobic modified gypsum ceramic powder to amine-terminated nitrile rubber is 10:2.5-3.

5.

7. The preparation method according to claim 1, characterized in that: The dispersant in step S3 is at least one of ethylene bis-stearamide, polyethylene wax, polypropylene wax, and paraffin wax.

8. The preparation method according to claim 1, characterized in that: In step S3, the plasticizer is at least one of the following: tributyl citrate, epoxidized soybean oil, dioctyl sebacate, trimethylolpropane, and triacetin.

9. A moisture-proof and pressure-resistant hollow board material containing waste ceramic gypsum, characterized in that: It is prepared by the preparation method described in any one of claims 1-8.

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