GRC raised floor and preparation method thereof

Abstract

The invention discloses a GRC raised floor and a preparation method thereof, and relates to the technical field of raised floors, the preparation method comprises the following operation steps: step 1, adding wood fibers into a mercaptopropyltrimethoxysilane-ethanol aqueous solution for hydrolysis reaction to obtain sulfhydrylated wood fibers; (2) adding the sulfhydrylated wood fiber, vinyl imidazole and benzoin diethyl ether into N, N-dimethylformamide, uniformly mixing, and irradiating under ultraviolet light for 1-2 hours to obtain modified wood fiber; 2, cement, sand, lightweight aggregate, a water reducing agent and flexible vinyl ester resin are evenly mixed, water is added, even mixing continues to be conducted for 10-20 min, then modified wood fibers and tartaric acid are added, even mixing is conducted, and cement paste is obtained; 3, the cement paste is placed in a mold, and air is exhausted; and the GRC raised flooring is sequentially subjected to primary curing, steam curing and demolding, and the GRC raised flooring is obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of raised floors, and specifically to a GRC raised floor and a preparation method thereof. Background Art

[0002] With the rapid development of modern building technology and the continuous improvement of people's requirements for the functionality of building spaces; among many building materials, GRC materials have been widely used in the construction field due to their unique performance advantages, and GRC raised floors are one of the important applications.

[0003] In some static-sensitive places, such as electronic equipment rooms, precision instrument rooms, etc., the generation of static electricity may cause damage to equipment and affect its normal operation; currently, some anti-static floors on the market mainly achieve anti-static functions through surface coatings or adding anti-static agents, but the anti-static effect of this method is often not lasting; ordinary cement-based raised floors, although having high strength, are heavy in texture, inconvenient to install, and have deficiencies in toughness and crack resistance, and are prone to problems such as cracking and breakage, affecting the use effect and safety.

[0004] In summary, in order to solve the above problems, the present invention provides an effective method for preparing GRC raised floors. Summary of the Invention

[0005] The purpose of the present invention is to provide a GRC raised floor and a preparation method thereof to solve the problems raised in the prior art.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] A preparation method of a GRC raised floor includes the following operation steps:

[0008] Step 1: (1) Add wood fiber to an aqueous solution of mercaptopropyltrimethoxysilane - ethanol for hydrolysis reaction to obtain mercapto-functionalized wood fiber; (2) Add mercapto-functionalized wood fiber, vinyl imidazole, 2-methyl-5-vinylpyridine, and benzoin ethyl ether to N,N-dimethylformamide and mix evenly, and irradiate with ultraviolet light for 1 - 2 hours to obtain modified wood fiber;

[0009] Step 2: Uniformly mix cement, sand, lightweight aggregate, water reducer, and flexible vinyl ester resin, add water, continue to mix evenly for 10 - 20 minutes, and then add modified wood fiber and tartaric acid and mix evenly to obtain a cement slurry;

[0010] Step 3: Place the cement slurry in a mold to remove air; perform primary curing, steam curing, and demolding on it in sequence to obtain a GRC raised floor.

[0011] More optimally, the raw materials of the cement slurry include the following components: by mass, 30 to 40 parts of cement, 30 to 40 parts of sand, 15 to 20 parts of lightweight aggregate, 0.1 to 0.3 parts of water reducer, 3 to 5 parts of flexible vinyl ester resin, 4 to 10 parts of modified wood fiber, 0.05 to 0.08 parts of tartaric acid, and 15 to 20 parts of water.

[0012] More optimally, the mass ratio of the wood fiber to mercaptopropyltrimethoxysilane is 1:(0.2-0.3); the raw materials of the modified wood fiber include the following components: by mass, 0.3-0.6 parts of thiolated wood fiber, 2-3 parts of vinylimidazole, 1-2 parts of 2-methyl-5-vinylpyridine, 0.002-0.0025 parts of benzoin ethyl ether, and 20-30 parts of N,N-dimethylformamide.

[0013] More optimally, the ethanol accounts for 70-80wt% of the ethanol aqueous solution; the temperature of the hydrolysis reaction is 70-80°C and the time is 3-4 hours.

[0014] More optimally, the raw materials of the water reducer include modified lignin water reducer and polycarboxylic acid water reducer in a mass ratio of 1:(3-4).

[0015] The preparation method of the modified lignin water reducer is more optimized as follows: (1) adding 2-chloroprene to DMSO and mixing uniformly to obtain a mixed solution; adding lignin to DMSO and mixing uniformly, adding triethylamine under nitrogen atmosphere and ice water bath conditions, mixing uniformly, dripping the mixed solution, dripping it for 1 to 2 hours, reacting it at 40 to 50° C. for 4 to 5 hours, cooling it to room temperature, adding a saturated sodium bicarbonate solution, filtering, washing, and drying to obtain modified lignin; (2) adding maleic anhydride and ascorbic acid to deionized water and mixing uniformly to obtain solution A; adding ammonium persulfate and mercaptoethanol to deionized water and mixing uniformly to obtain solution B; adding modified lignin and isopentenol polyoxyethylene ether to deionized water, mixing uniformly, heating it to 75 to 80° C., adding sodium dodecyl sulfate and mixing uniformly, dripping solution A and solution B, dripping it for 2 to 3 hours, reacting it for 1 to 2 hours, adjusting the pH to neutral, and obtaining a modified lignin water reducer.

[0016] More optimally, the raw materials of the modified lignin include the following components: 1 to 2 parts of lignin, 0.5 to 1.3 parts of triethylamine, and 3 to 4 parts of 2-chloroprene.

[0017] More optimally, the raw materials of the modified lignin water reducer include the following components: 4 to 6 parts by mass of isopentanol polyoxyethylene ether, 2 to 3 parts of modified lignin, and 1 to 3 parts of maleic anhydride.

[0018] More optimally, the ascorbic acid accounts for 0.7-1.2wt% of the modified lignin water reducer; the ammonium persulfate accounts for 0.6-0.8wt% of the modified lignin water reducer; the mercaptoethanol accounts for 0.3-0.5wt% of the modified lignin water reducer; and the sodium dodecyl sulfate accounts for 0.5-0.7wt% of the modified lignin water reducer.

[0019] The more optimized process conditions for the preliminary curing are: the curing temperature is 20-30°C, the curing humidity is 80-90%, and the curing time is 12-14 hours; the process conditions for the steam curing are: the curing temperature is 70-80°C, and the curing time is 13-18 hours.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] In this scheme, cement, sand, lightweight aggregate (ceramsite), water reducing agent, flexible vinyl ester resin, wood fiber and tartaric acid are uniformly mixed to obtain cement slurry; the slurry is placed in a mold, and preliminary curing, steam curing and demolding are performed in sequence to obtain the GRC raised floor.

[0022] In the plan, preliminary curing and steam curing are carried out to promote the full hydration of cement and improve the strength and durability of the floor.

[0023] In order to improve the collapse resistance and durability of GRC elevated floors; although polycarboxylic acid water reducer has good water reduction effect, it has certain limitations in maintaining the slump of concrete, and lignin has a certain air entraining effect; adding lignin water reducer can effectively reduce the amount of polycarboxylic acid water reducer added, thereby reducing the cost. It has a certain collapse resistance for GRC floors and can improve the sensitivity of polycarboxylic acid water reducer in GRC floors.

[0024] In the scheme, lignin is modified by triethylamine and 2-chloroprene to obtain modified lignin; then maleic anhydride, isopentanol polyoxyethylene ether and the modified lignin are polymerized to obtain a lignin water reducer;

[0025] Among them, butadiene has good flexibility and elasticity. After being grafted onto lignin, it can effectively improve the toughness of the material and make it less likely to break. Its hydrophobicity is relatively strong. After being grafted onto lignin, it can form a relatively hydrophobic protective layer on the surface of lignin. When the material comes into contact with water, it can prevent the invasion of water molecules, reduce the water absorption rate of the material, and improve the water resistance of the material, so that it has better stability and durability in humid environments or application scenarios in contact with water. Polyoxyethylene ether substances have certain hydrophilicity and flexible chain segments. Flexible chain segments can increase the mobility of molecules, which is beneficial to the transfer and dissipation of charges, thereby improving the anti-static performance to a certain extent.

[0026] Therefore, the combined use of lignin water reducer and polycarboxylic acid water reducer can form a denser adsorption layer on the surface of cement particles, further improve the water reduction rate, and enable the GRC material to further reduce the water-cement ratio while maintaining fluidity, making the concrete structure more compact, reducing porosity, and effectively improving the collapse resistance of concrete while increasing strength.

[0027] In order to improve the antistatic effect of GRC elevated floor, antistatic agent is added therein; however, the antistatic effect of traditional antistatic agent is greatly affected by ambient temperature and humidity, and the durability is poor; therefore, in the scheme, wood fiber is grafted with vinyl imidazole and 2-methyl-5-vinyl pyridine to obtain modified wood fiber; vinyl imidazole and 2-methyl-5-vinyl pyridine form a conductive network on the surface of wood fiber, and the two work synergistically to form a denser and continuous conductive channel, thereby enhancing the long-lasting and stable antistatic performance of GRC elevated floor.

[0028] In addition, wood fibers containing imidazole and pyridine groups can affect the charge distribution on the surface of cement particles, and cooperate with the dispersing effect of the water reducer to make the cement particles more evenly dispersed in the system and prevent the agglomeration of cement particles, which helps to improve the compatibility of wood fibers and cement water reducers in the entire cement system. DETAILED DESCRIPTION

[0029] In the following specific implementation methods, parts are parts by mass; the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the following specific embodiments, parts are by mass. In this embodiment, it should be noted that the purchase manufacturers of all raw materials involved in the present invention are not subject to any special restrictions. Examples include: cement is silicate cement, the article number is WD3042, purchased from Hubei Wande Chemical Co., Ltd.; sand is quartz sand (25-50 mesh), the article number is CFEQ-4-441862-1000, purchased from Shanghai Anpu Experimental Technology Co., Ltd.; lightweight aggregate is ceramsite, with a density of 0.92g / cm3 and a particle size of 8-10, purchased from Kelong Petrochemical Equipment Material Co., Ltd., Pingxiang City, Jiangxi Province; the model of flexible vinyl ester resin is TMR-158, purchased from Jinan Jingsheng Chemical Co., Ltd.; wood fiber is log pulp fiber, with a particle size of 85.73μm and a purity of 98.23%, purchased from Shijiazhuang Xinyuan Cellulose Co., Ltd.; tartaric acid has a CAS number of 526-83-0, purchased from Fuchen (Tianjin) Chemical Reagent Co., Ltd.; The CAS number of mercaptopropyltrimethoxysilane is 4420-74-0; the CAS number of vinylimidazole is 1072-63-5; the CAS number of 2-methyl-5-vinylpyridine is 140-76-1; the CAS number of benzoin ethyl ether is 574-09-4; the CAS number of 2-chloroprene is 126-99-8; the lignin is alkaline lignin, CAS number 8068-05-1, purchased from Hubei Xinrunde Chemical Co., Ltd. ; The molecular weight of isopentanol polyoxyethylene ether is 2400, purchased from Wuhan Xinxin Jiali Biotechnology Co., Ltd.; the CAS number of maleic anhydride is 108-31-6; the CAS number of triethylamine is 121-44-8; the CAS number of ammonium persulfate is 7727-54-0; the CAS number of mercaptoethanol is 60-24-2, the CAS number of ascorbic acid is 299-36-5; the CAS number of sodium dodecyl sulfate is 151-21-3.

[0031] The preparation method of the modified lignin water reducer is as follows: (1) adding 3 parts of 2-chloroprene to 10 parts of DMSO and mixing them uniformly to obtain a mixed solution; adding 1.6 parts of lignin to 20 parts of DMSO and mixing them uniformly, adding 1.3 parts of triethylamine under nitrogen atmosphere and ice water bath conditions, mixing them uniformly, dripping the mixed solution, dripping it all over in 2 hours, reacting it at 45°C for 5 hours, cooling it to room temperature, adding a saturated sodium bicarbonate solution, filtering, washing, and drying to obtain modified lignin; (2) adding 3 parts of maleic anhydride and ascorbic acid to deionized water and mixing them uniformly to obtain solution A; adding ammonium persulfate and mercaptoethanol to deionized water and mixing them uniformly to obtain solution B; adding 2 parts of modified lignin and 6 parts of isopentanol polyoxyethylene ether to deionized water, mixing them uniformly, heating it to 80°C, adding sodium dodecyl sulfate and mixing them uniformly, dripping solution A and solution B, dripping it all over in 2 hours, reacting it for 2 hours, adjusting the pH to neutral, and obtaining a modified lignin water reducer;

[0032] Among them, ascorbic acid accounts for 0.8wt% of the modified lignin water reducer; ammonium persulfate accounts for 0.6wt% of the modified lignin water reducer; mercaptoethanol accounts for 0.45wt% of the modified lignin water reducer; sodium dodecyl sulfate accounts for 0.6wt% of the modified lignin water reducer.

[0033] Embodiment 1: A method for preparing a GRC raised floor, comprising the following steps;

[0034] Step 1: (1) adding wood fiber to a mercaptopropyltrimethoxysilane-ethanol aqueous solution and reacting at 80° C. for 3 hours to obtain mercaptolated wood fiber; wherein the mass ratio of wood fiber to mercaptopropyltrimethoxysilane is 1:0.3;

[0035] (2) adding 0.5 parts of thiolated wood fiber, 2 parts of vinyl imidazole, 1 part of 2-methyl-5-vinyl pyridine, and 0.002 parts of benzoin ethyl ether to 25 parts of N,N-dimethylformamide, uniformly mixing, irradiating under ultraviolet light for 2 hours, washing, and drying to obtain modified wood fiber;

[0036] Step 2: 30 parts of cement, 30 parts of sand, 15 parts of ceramsite, 0.1 parts of water reducer, and 5 parts of flexible vinyl ester resin were uniformly mixed, 20 parts of water were added, and the mixture was uniformly mixed for 20 minutes, and 4 parts of modified wood fiber and 0.05 parts of tartaric acid were added and uniformly mixed to obtain cement paste;

[0037] The raw materials of the water reducer include a modified lignin water reducer and a polycarboxylic acid water reducer in a mass ratio of 1:4;

[0038] Step 3: Place the cement slurry in a mold and remove the air; perform preliminary curing at a temperature of 25°C and a humidity of 80% for 12 hours, then perform steam curing at a temperature of 80°C for 15 hours, and then demold the mold to obtain a GRC raised floor.

[0039] Embodiment 2: A method for preparing a GRC raised floor, comprising the following steps;

[0040] Step 1: (1) adding wood fiber to a mercaptopropyltrimethoxysilane-ethanol aqueous solution and reacting at 80° C. for 3 hours to obtain mercaptolated wood fiber; wherein the mass ratio of wood fiber to mercaptopropyltrimethoxysilane is 1:0.3;

[0041] (2) adding 0.5 parts of thiolated wood fiber, 2 parts of vinyl imidazole, 1 part of 2-methyl-5-vinyl pyridine, and 0.002 parts of benzoin ethyl ether to 20 to 30 parts of N,N-dimethylformamide, uniformly mixing, irradiating under ultraviolet light for 2 hours, washing, and drying to obtain modified wood fiber;

[0042] Step 2: 30 parts of cement, 40 parts of sand, 20 parts of ceramsite, 0.1 parts of water reducer, and 5 parts of flexible vinyl ester resin were uniformly mixed, 20 parts of water were added, and the mixture was uniformly mixed for 20 minutes, and 10 parts of modified wood fiber and 0.05 parts of tartaric acid were added and uniformly mixed to obtain cement paste;

[0043] The raw materials of the water reducer include a modified lignin water reducer and a polycarboxylic acid water reducer in a mass ratio of 1:4;

[0044] Step 3: Place the cement slurry in a mold and remove the air; perform preliminary curing at a temperature of 25°C and a humidity of 80% for 12 hours, then perform steam curing at a temperature of 80°C for 15 hours, and then demold the mold to obtain a GRC raised floor.

[0045] Embodiment 3: A method for preparing a GRC raised floor, comprising the following steps;

[0046] Step 1: (1) adding wood fiber to a mercaptopropyltrimethoxysilane-ethanol aqueous solution and reacting at 80° C. for 3 hours to obtain mercaptolated wood fiber; wherein the mass ratio of wood fiber to mercaptopropyltrimethoxysilane is 1:0.3;

[0047] (2) adding 0.5 parts of thiolated wood fiber, 2 parts of vinyl imidazole, 1 part of 2-methyl-5-vinyl pyridine, and 0.002 parts of benzoin ethyl ether to 25 parts of N,N-dimethylformamide, uniformly mixing, irradiating under ultraviolet light for 2 hours, washing, and drying to obtain modified wood fiber;

[0048] Step 2: 30 parts of cement, 30 parts of sand, 15 parts of ceramsite, 0.1 parts of water reducer, and 5 parts of flexible vinyl ester resin were uniformly mixed, 20 parts of water were added, and the mixture was uniformly mixed for 20 minutes, and 7 parts of modified wood fiber and 0.05 parts of tartaric acid were added and uniformly mixed to obtain cement paste;

[0049] The raw materials of the water reducer include a modified lignin water reducer and a polycarboxylic acid water reducer in a mass ratio of 1:4;

[0050] Step 3: Place the cement slurry in a mold and remove the air; perform preliminary curing at a temperature of 25°C and a humidity of 80% for 12 hours, then perform steam curing at a temperature of 80°C for 15 hours, and then demold the mold to obtain a GRC raised floor.

[0051] Comparative Example 1 is based on Example 2, but vinyl imidazole is not introduced into the modified wood fiber;

[0052] Step 1: (1) Add wood fiber into the aqueous solution of mercaptopropyltrimethoxysilane - ethanol, and react at 80 °C for 3 hours to obtain mercapto - modified wood fiber; wherein, the mass ratio of wood fiber to mercaptopropyltrimethoxysilane is 1:0.3;

[0053] (2) Add 0.5 part of mercapto - modified wood fiber, 1 part of 2 - methyl - 5 - vinylpyridine, and 0.002 part of benzoin ethyl ether into 25 parts of N,N - dimethylformamide, mix evenly, irradiate under ultraviolet light for 2 hours, wash, and dry to obtain modified wood fiber;

[0054] Step 2: Add 30 parts of cement, 40 parts of sand, 30 parts of ceramsite, 0.1 part of water - reducing agent, and 5 parts of flexible vinyl ester resin, mix evenly, add 20 parts of water, continue to mix evenly for 20 minutes, then add 10 parts of modified wood fiber and 0.05 part of tartaric acid and mix evenly to obtain cement paste;

[0055] Among them, the raw materials of the water - reducing agent include modified lignin water - reducing agent and polycarboxylate water - reducing agent with a mass ratio of 1:4;

[0056] Step 3: Place the cement paste in a mold to remove air; cure it preliminarily at 25 °C and 80% humidity for 12 hours, then cure it by steam at 80 °C for 15 hours, and demold to obtain a GRC overhead floor.

[0057] Comparative Example 2 is based on Example 2, with only polycarboxylate water - reducing agent added;

[0058] Step 1: (1) Add wood fiber into the aqueous solution of mercaptopropyltrimethoxysilane - ethanol, and react at 80 °C for 3 hours to obtain mercapto - modified wood fiber; wherein, the mass ratio of wood fiber to mercaptopropyltrimethoxysilane is 1:0.3;

[0059] (2) Add 0.5 part of mercapto - modified wood fiber, 2 parts of vinyl imidazole, 1 part of 2 - methyl - 5 - vinylpyridine, and 0.002 part of benzoin ethyl ether into 25 parts of N,N - dimethylformamide, mix evenly, irradiate under ultraviolet light for 2 hours, wash, and dry to obtain modified wood fiber;

[0060] Step 2: Add 30 parts of cement, 40 parts of sand, 20 parts of ceramsite, 0.1 part of polycarboxylate water - reducing agent, and 5 parts of flexible vinyl ester resin, mix evenly, add 20 parts of water, continue to mix evenly for 20 minutes, then add 10 parts of modified wood fiber and 0.05 part of tartaric acid and mix evenly to obtain cement paste;

[0061] Step 3: Place the cement slurry in a mold and remove the air; perform preliminary curing at a temperature of 25°C and a humidity of 80% for 12 hours, then perform steam curing at a temperature of 80°C for 15 hours, and then demold the mold to obtain a GRC raised floor.

[0062] Comparative Example 3 is based on Example 2, and the mass ratio of lignin water reducer to polycarboxylic acid water reducer is 4:1;

[0063] Step 1: (1) adding wood fiber to a mercaptopropyltrimethoxysilane-ethanol aqueous solution and reacting at 80° C. for 3 hours to obtain mercaptolated wood fiber; wherein the mass ratio of wood fiber to mercaptopropyltrimethoxysilane is 1:0.3;

[0064] (2) adding 0.5 parts of thiolated wood fiber, 2 parts of vinyl imidazole, 1 part of 2-methyl-5-vinyl pyridine, and 0.002 parts of benzoin ethyl ether to 25 parts of N,N-dimethylformamide, uniformly mixing, irradiating under ultraviolet light for 2 hours, washing, and drying to obtain modified wood fiber;

[0065] Step 2: 30 parts of cement, 40 parts of sand, 20 parts of ceramsite, 0.1 parts of water reducer, and 5 parts of flexible vinyl ester resin were uniformly mixed, 20 parts of water were added, and the mixture was uniformly mixed for 20 minutes, and 10 parts of modified wood fiber and 0.05 parts of tartaric acid were added and uniformly mixed to obtain cement paste;

[0066] The raw materials of the water reducer include a modified lignin water reducer and a polycarboxylic acid water reducer in a mass ratio of 4:1;

[0067] Step 3: Place the cement slurry in a mold and remove the air; perform preliminary curing at a temperature of 25°C and a humidity of 80% for 12 hours, then perform steam curing at a temperature of 80°C for 15 hours, and then demold the mold to obtain a GRC raised floor.

[0068] Comparative Example 4 is based on Example 2, but no steam curing is performed;

[0069] Step 1: (1) adding wood fiber to a mercaptopropyltrimethoxysilane-ethanol aqueous solution and reacting at 80° C. for 3 hours to obtain mercaptolated wood fiber; wherein the mass ratio of wood fiber to mercaptopropyltrimethoxysilane is 1:0.3;

[0070] (2) adding 0.5 parts of thiolated wood fiber, 2 parts of vinyl imidazole, and 0.002 parts of benzoin ethyl ether to 25 parts of N,N-dimethylformamide, uniformly mixing, irradiating under ultraviolet light for 2 hours, washing, and drying to obtain modified wood fiber;

[0071] Step 2: 30 parts of cement, 40 parts of sand, 20 parts of ceramsite, 0.1 parts of water reducer, and 5 parts of flexible vinyl ester resin were uniformly mixed, 20 parts of water were added, and the mixture was uniformly mixed for 20 minutes, and 10 parts of modified wood fiber and 0.05 parts of tartaric acid were added and uniformly mixed to obtain cement paste;

[0072] The raw materials of the water reducer include a modified lignin water reducer and a polycarboxylic acid water reducer in a mass ratio of 1:4;

[0073] Step 3: Place the cement paste in a mold and remove the air; cure it at a temperature of 25° C. and a humidity of 80% for 12 hours to obtain a GRC raised floor.

[0074] Testing test: According to JC / T2461-2018 "Test method for mechanical properties of high ductility fiber reinforced cement-based composite materials", the compressive strength test of the ECC raised floor for heating prepared in Examples 1 to 3 and Comparative Examples 1 to 3 was carried out using an MTS universal testing machine; and the antistatic effects of Examples 1 to 3 and Comparative Examples 1 to 3 were tested;

[0075] Surface resistivity(Ω.m) Compressive strength(MPa) Example 1 <![CDATA[1.30×10 7 ]]> 52.4 Example 2 <![CDATA[1.25×10 7 ]]> 55.7 Example 3 <![CDATA[1.28×10 7 ]]> 53.6 Comparative Example 1 <![CDATA[1.35×10 7 ]]> 50.8 Comparative Example 2 <![CDATA[1.42×10 7 ]]> 47.2 Comparative Example 3 <![CDATA[1.63×10 7 > 43.7 Comparative Example 4 <![CDATA[1.52×10 7 ]]> 40.8

[0076] Table 1

[0077] Conclusion: Comparative Example 1 is based on Example 2, and vinylimidazole is not introduced into the modified wood fiber, resulting in a decrease in the performance of the GRC elevated floor; the addition of a single polycarboxylic acid water reducer causes the performance of the GRC elevated floor in Comparative Example 1 to be lower than that of the elevated floor in Example 2; Comparative Example 3 is based on Example 2, and the mass ratio of lignin water reducer to polycarboxylic acid water reducer is 4:1, resulting in a decrease in fluidity, thereby causing the performance of the GRC elevated floor in Comparative Example 3 to decrease; Comparative Example 4 is based on Example 2, and steam curing is not performed, resulting in a decrease in the character of the GRC elevated floor.

[0078] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

Claims

1. A method for preparing a GRC raised floor, characterized in that: The steps include: Step 1: (1) adding wood fiber to a mercaptopropyltrimethoxysilane-ethanol aqueous solution for hydrolysis reaction to obtain thiolated wood fiber; (2) adding thiolated wood fiber, vinyl imidazole, 2-methyl-5-vinylpyridine, and benzoin ethyl ether to N,N-dimethylformamide, uniformly mixing, and irradiating under ultraviolet light for 1 to 2 hours to obtain modified wood fiber; Step 2: Evenly mix cement, sand, lightweight aggregate, water reducing agent, and flexible vinyl ester resin, add water, continue to evenly mix for 10 to 20 minutes, then add modified wood fiber and tartaric acid and evenly mix to obtain cement paste; Step 3: Place the cement slurry in a mold and remove the air; perform preliminary curing, steam curing, and demolding in sequence to obtain the GRC raised floor.

2. The method for preparing a GRC raised floor according to claim 1, characterized in that: The raw materials of the cement paste include the following components: by mass, 30-40 parts of cement, 30-40 parts of sand, 15-20 parts of lightweight aggregate, 0.1-0.3 parts of water reducer, 3-5 parts of flexible vinyl ester resin, 4-10 parts of modified wood fiber, 0.05-0.08 parts of tartaric acid, and 15-20 parts of water.

3. The method for preparing a GRC raised floor according to claim 1, characterized in that: The mass ratio of the wood fiber to mercaptopropyltrimethoxysilane is 1:(0.2-0.3); the raw materials of the modified wood fiber include the following components: by mass, 0.3-0.6 parts of thiolated wood fiber, 2-3 parts of vinylimidazole, 1-2 parts of 2-methyl-5-vinylpyridine, 0.002-0.0025 parts of benzoin ethyl ether, and 20-30 parts of N,N-dimethylformamide.

4. The method for preparing a GRC raised floor according to claim 1, characterized in that: The ethanol accounts for 70-80 wt% of the ethanol aqueous solution; the temperature of the hydrolysis reaction is 70-80° C. and the time is 3-4 hours.

5. The method for preparing a GRC raised floor according to claim 2, characterized in that: The raw materials of the water reducer include a modified lignin water reducer and a polycarboxylic acid water reducer in a mass ratio of 1:(3-4).

6. The method for preparing a GRC raised floor according to claim 5, characterized in that: The preparation method of the modified lignin water reducer is as follows: (1) adding 2-chloroprene to DMSO and mixing uniformly to obtain a mixed solution; adding lignin to DMSO and mixing uniformly, adding triethylamine under nitrogen atmosphere and ice water bath conditions, mixing uniformly, dripping the mixed solution, dripping it for 1 to 2 hours, reacting it at 40 to 50° C. for 4 to 5 hours, cooling it to room temperature, adding a saturated sodium bicarbonate solution, filtering, washing, and drying to obtain modified lignin; (2) adding maleic anhydride and ascorbic acid to deionized water and mixing uniformly to obtain solution A; adding ammonium persulfate and mercaptoethanol to deionized water and mixing uniformly to obtain solution B; adding modified lignin and isopentenol polyoxyethylene ether to deionized water, mixing uniformly, heating it to 75 to 80° C., adding sodium dodecyl sulfate and mixing uniformly, dripping solution A and solution B, dripping it for 2 to 3 hours, reacting it for 1 to 2 hours, adjusting the pH to neutral, and obtaining a modified lignin water reducer.

7. The method for preparing a GRC raised floor according to claim 6, characterized in that: The raw materials of the modified lignin include the following components: 1 to 2 parts of lignin, 0.5 to 1.3 parts of triethylamine, and 3 to 4 parts of 2-chloroprene by mass.

8. The method for preparing a GRC raised floor according to claim 6, characterized in that: The raw materials of the modified lignin water reducer include the following components: by weight, 4 to 6 parts of isopentanol polyoxyethylene ether, 2 to 3 parts of modified lignin, and 1 to 3 parts of maleic anhydride; the ascorbic acid accounts for 0.7 to 1.2 wt% of the modified lignin water reducer; the ammonium persulfate accounts for 0.6 to 0.8 wt% of the modified lignin water reducer; the mercaptoethanol accounts for 0.3 to 0.5 wt% of the modified lignin water reducer; and the sodium dodecyl sulfate accounts for 0.5 to 0.7 wt% of the modified lignin water reducer.

9. The method for preparing a GRC raised floor according to claim 1, characterized in that: The process conditions of the preliminary curing are: the curing temperature is 20-30° C., the curing humidity is 80-90%, and the curing time is 12-14 hours; the process conditions of the steam curing are: the curing temperature is 70-80° C., and the curing time is 13-18 hours.

10. A GRC elevated floor is prepared according to the method for preparing a GRC elevated floor according to any one of claims 1 to 9.