Reed fiber-based concrete, lightweight concrete building block and preparation method and application of lightweight concrete building block
By cross-winding reed fibers in reed fiber-based concrete and building a multi-bonded network structure, the problem of insufficient mechanical strength of reed fiber-based concrete porous blocks in the prior art is solved, and a lightweight concrete block with high mechanical strength, water resistance and durability is achieved.
Patent Information
- Application Number
- CN202411725690.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-28
- Publication Date
- 2025-02-28
AI Technical Summary
The porous blocks of existing reed fiber-based concrete have problems such as high brittleness, incompatible interfaces and poor stability, resulting in weak mechanical strength.
Using a combination of 300 to 500 parts of reed fiber, 1000 to 1600 parts of cement, 2 to 10 parts of manganese dioxide, 2 to 90 parts of foam stabilizer, 2 to 15.3 parts of chelate of metal ions and organic polymers, and 45 to 80 parts of foaming agent, the interfacial load transfer efficiency is improved by cross-winding reed fibers and constructing a multi-bonded network structure.
The mechanical strength, water resistance and durability of reed fiber-based concrete is significantly improved, forming a concrete lightweight block with excellent properties.
Smart Images
Figure BDA0005159145520000071
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of composite materials, and in particular to a reed fiber-based concrete, a lightweight concrete block, and a preparation method and application thereof. Background Art
[0002] The yield of reeds is generally large, and after pulp and paper production stopped production, a large amount of reed resources were wasted. At the same time, traditional concrete is mostly made of cement dry materials and sand and gravel, which are non-renewable resources and have high density. The preparation of reed fiber-based concrete porous blocks by compounding reed fibers with a large aspect ratio with cement dry materials can improve resource utilization, protect the ecological environment, and contribute to dual carbon.
[0003] In the prior art, reed fiber-based concrete is usually prepared by simply mixing reed crushed materials with cement. The porous blocks prepared by this concrete have the problems of high brittleness, interface incompatibility and poor stability, resulting in weak mechanical strength. Summary of the invention
[0004] The purpose of the present invention is to provide a reed fiber-based concrete, a lightweight concrete block, and a preparation method and application thereof. The lightweight concrete block prepared by using the reed fiber-based concrete provided by the present invention has excellent mechanical strength.
[0005] In order to achieve the purpose of the present invention, the present invention provides the following technical solutions:
[0006] The invention discloses a reed fiber-based concrete. The raw materials for preparing the reed fiber-based concrete include, by weight, 300-500 parts of reed fiber, 1000-1600 parts of cement, 2-10 parts of manganese dioxide, 25-90 parts of foam stabilizer, 2-15.3 parts of chelate of metal ion and organic polymer and 45-80 parts of foaming agent.
[0007] Preferably, the organic polymer is one or more of polyvinyl acetate, vinyl acetate-ethylene copolymer, polysaccharide and cellulose.
[0008] Preferably, the metal ions are alkali metal ions and / or alkaline earth metal ions.
[0009] Preferably, the foam stabilizer includes one or more of polyvinyl alcohol, sodium dodecylbenzene sulfonate and calcium stearate.
[0010] Preferably, the foaming agent includes one or more of hydrogen peroxide, aluminum powder and baking soda.
[0011] The present invention also provides a method for preparing the reed fiber-based concrete according to the above technical solution, comprising the following steps:
[0012] The reed fiber-based concrete is obtained by mixing reed fiber, cement, manganese dioxide, a foam stabilizer, a chelate of metal ions and organic polymers, a foaming agent and water.
[0013] Preferably, the length of a single fiber in the reed fiber bundle is 12-36 mm, the diameter is 0.24-0.4 mm, and the aspect ratio is 50-90.
[0014] The present invention also provides a lightweight concrete block, wherein the material of the lightweight concrete block is the reed fiber-based concrete described in the above technical solution or the reed fiber-based concrete prepared by the preparation method described in the above technical solution; the lightweight concrete block has a porosity of 60% to 90% and a density of 0.2 to 0.6 g / cm 3 .
[0015] The present invention also provides a method for preparing the lightweight concrete block according to the above technical solution, which is characterized by comprising the following steps:
[0016] The reed fiber-based concrete and water are mixed, and the slurry is formed and then solidified to obtain the concrete lightweight building block.
[0017] The present invention also provides the use of the reed fiber-based concrete described in the above technical solution, the reed fiber-based concrete prepared by the preparation method described in the above technical solution, the concrete lightweight block described in the above technical solution, or the concrete lightweight block prepared by the preparation method described in the above technical solution in building materials, fireproof materials or agricultural materials.
[0018] The present invention provides a reed fiber-based concrete, wherein the raw materials for preparing the reed fiber-based concrete include 300-500 parts of reed fiber, 1000-1600 parts of cement, 2-10 parts of manganese dioxide, 25-90 parts of foam stabilizer, 2-15.3 parts of chelate of metal ion and organic polymer and 45-80 parts of foaming agent by weight. The reed fiber of the present invention is cross-entangled in the concrete system to provide support strength, and the present invention adopts the chelate of metal ion and organic polymer to construct a metal bond, covalent bond and hydrogen bond multi-bonding network structure at the organic / inorganic heterogeneous interface of the reed fiber-based concrete, thereby improving the interface load transfer efficiency, thereby improving the mechanical strength of the reed fiber-based concrete, and improving the water resistance and durability of the reed fiber-based concrete by chelating the metal ion and the polymer into a tough molecular membrane.
[0019] The present invention also provides a method for preparing the reed fiber-based concrete described in the above technical solution. The preparation method of the present invention is simple and has the advantages of low cost, renewable resources, green environmental protection, and large-scale production, which is conducive to industrial application.
[0020] In addition, the present invention obtains reed fiber by removing lignin and separating fibers from reeds, thereby increasing the specific surface area of the reed fiber and the active sites on the reed fiber, improving the interface compatibility of reed / cement, and further improving the mechanical strength of reed fiber-based concrete. DETAILED DESCRIPTION
[0021] The invention provides a reed fiber-based concrete. The raw materials for preparing the reed fiber-based concrete include, by weight, 300-500 parts of reed fibers, 1000-1600 parts of cement, 2-10 parts of manganese dioxide, 25-90 parts of foam stabilizers, 2-15.3 parts of chelates of metal ions and organic polymers, and 45-80 parts of foaming agents.
[0022] In the present invention, unless otherwise specified, all preparation raw materials are commercially available products well known to those skilled in the art.
[0023] In the present invention, the reed fiber-based concrete includes 300 to 500 parts of reed fiber by weight, and in a specific embodiment, it can be 350, 380, 400 or 450 parts; the length of a single fiber in the reed fiber bundle is 12 to 36 mm, and in a specific embodiment, it can be 18 mm, 24 mm or 30 mm; the diameter is 0.24 to 0.4 mm, and in a specific embodiment, it can be 0.3 mm; the aspect ratio is 50 to 90, and in a specific embodiment, it can be 60 or 80; the specific surface area is 1.6 to 2.8 m 2 / g, in a specific embodiment, it can be 2m 2 / g. The reed fiber of the present invention is cross-entangled in the concrete system to provide supporting strength.
[0024] In the present invention, the reed fiber is obtained by removing lignin and separating fibers from reeds in sequence; the particle size of the reed can be 10-40 meshes, and in a specific embodiment, it can be 20 or 30 meshes; the moisture content can be 7%-13%, and in a specific embodiment, it can be 8%, 10% or 11%; the reagent used for removing lignin is sodium hydroxide and / or sodium hypochlorite, and in a specific embodiment, it can be a sodium hydroxide and sodium hypochlorite composite solution; the mass ratio of sodium hydroxide and sodium hypochlorite in the sodium hydroxide and sodium hypochlorite composite solution is 1-3:1-3, and in a specific embodiment, it can be 2:1, 1:1 or 1:2; the total concentration is 2%-10%, and in a specific embodiment, it can be 6%; the temperature of the chemical removal is 80-100°C, and in a specific embodiment, it can be 85°C, and the time is 3-4h. In the process of removing lignin, the present invention also removes impurity sugars in the reed.
[0025] In the present invention, the fiber separation method can be hydrothermal microwave combined treatment and dispersion in sequence; the temperature of the hydrothermal microwave combined treatment is 100-120°C, in a specific embodiment, it can be 120°C; the time is 8-12 minutes, in a specific embodiment, it can be 10 minutes; the microwave frequency is 2000-3000MHz, in a specific embodiment, it can be 2500MHz; the dispersion equipment can be a hot mill. The present invention physically separates reed fibers by hydrothermal microwave combined treatment.
[0026] In the present invention, the reed fiber-based concrete includes 1000-1600 parts of cement by weight, and in a specific embodiment, it can be 1200, 1400 or 1500 parts; the cement can be Portland cement, and in a specific embodiment, it can be Portland cement clinker; the mineral composition of the Portland cement includes tricalcium silicate, dicalcium silicate, tricalcium aluminate and tetracalcium aluminoferrite; the total mass fraction of the tricalcium silicate and dicalcium silicate is 80-85wt%. In the present invention, cement is the matrix of the block and can be glued with reed fiber.
[0027] In the present invention, the reed fiber-based concrete includes 2 to 10 parts by weight of manganese dioxide, and in specific embodiments, it may be 5, 7 or 9 parts. The manganese dioxide of the present invention is used as a catalyst to catalyze the foaming agent to foam.
[0028] In the present invention, the reed fiber-based concrete includes 25 to 90 parts by weight of a foam stabilizer, and in a specific embodiment, it can be 30, 50 or 70 parts; the foam stabilizer includes one or more of polyvinyl alcohol, sodium dodecylbenzene sulfonate and calcium stearate, and in a specific embodiment, it can be calcium stearate.
[0029] In the present invention, the reed fiber-based concrete includes 45 to 80 parts of a foaming agent by weight, and in a specific embodiment, it can be 50, 60 or 70 parts; the foaming agent includes one or more of hydrogen peroxide, aluminum powder and baking soda, and in a specific embodiment, it can be hydrogen peroxide; the mass percentage of hydrogen peroxide in the hydrogen peroxide is 20% to 40%, and in a specific embodiment, it can be 30%.
[0030] In the present invention, the reed fiber-based concrete includes 2 to 15.3 parts of a chelate of metal ions and an organic polymer by weight, and in a specific embodiment, it can be 6, 8, 10 or 14 parts; the organic polymer includes one or more of polyvinyl acetate (EVA), vinyl acetate-ethylene copolymer (VAE), polysaccharide and cellulose; the EVA and VAE are used in the form of emulsion, and the solid content of the EVA emulsion and the VAE emulsion is independently 75% to 90%, and in a specific embodiment, it can be 85%; the cellulose can be hydroxymethyl cellulose and / or methyl cellulose; The polysaccharide can be one or more of starch, gum arabic, maltose and tianqing gum, and the molecular weight of the polysaccharide can be 50,000 to 150,000; the metal ions are alkali metal ions and / or alkaline earth metal ions; the alkali metal ions can be magnesium ions or lithium ions; the alkaline earth metal ions can be calcium ions; in a specific embodiment, the chelate of the metal ion and the organic polymer can be a chelate of magnesium ions and EVA emulsion; the mass percentage of the metal ion in the chelate of the metal ion and the organic polymer is 0.3% to 1.2%, and in a specific embodiment, it can be 0.6% or 0.9%.
[0031] The present invention adopts chelates of metal ions and organic polymers to construct a metal bond, covalent bond, and hydrogen bond multiple bonding network structure at the organic / inorganic heterogeneous interface of reed fiber-based concrete, thereby improving the interface load transfer efficiency, thereby improving the mechanical strength of the reed fiber-based concrete, and forming a tough molecular membrane through the chelation of metal ions and polymers, thereby improving the water resistance and durability of the reed fiber-based concrete.
[0032] The present invention also provides a method for preparing the reed fiber-based concrete according to the above technical solution, comprising the following steps:
[0033] The reed fiber-based concrete is obtained by mixing reed fiber, cement, manganese dioxide, a foam stabilizer, a chelate of metal ions and organic polymers, a foaming agent and water.
[0034] In the present invention, reed fiber, foam stabilizer and cement are first mixed to obtain mixture A; manganese dioxide and water are secondly mixed to obtain suspension B; the mixture A and suspension B are thirdly mixed to obtain slurry C; the chelate of metal ions and organic polymers and the slurry C are fourthly mixed to obtain mixture D; and the foaming agent and the mixture D are fifthly mixed to obtain reed fiber-based concrete.
[0035] In the present invention, the mass ratio of the manganese dioxide to water may be 2-10:600-900. In a specific embodiment, the mass ratio may be 5:650, 8:700 or 9.8:880.
[0036] In the present invention, the temperature of the third mixing can be 20-50° C., and in a specific embodiment, can be 30 or 40° C. The present invention controls the temperature of the third mixing within the above range, which is beneficial to internal chemical bonding.
[0037] In the present invention, the fifth mixing time is 8 to 12 seconds, and in a specific embodiment, it can be 10 or 11 seconds.
[0038] In the present invention, the first to fifth mixing methods are stirring and mixing, and the present invention has no particular limitation on the rotation speed of the stirring and mixing.
[0039] The present invention also provides a lightweight concrete block, wherein the material of the lightweight concrete block is the reed fiber-based concrete described in the above technical solution or the reed fiber-based concrete prepared by the preparation method described in the above technical solution; the porosity of the lightweight concrete block is 60% to 90%, and in a specific embodiment, it can be 70% or 80%; the density is 0.2 to 0.6 g / cm 3 In a specific embodiment, it can be 0.3 g / cm 3 , 0.4g / cm 3 or 0.5g / cm 3 .
[0040] The present invention also provides a method for preparing the lightweight concrete block according to the above technical solution, which is characterized by comprising the following steps:
[0041] The reed fiber-based concrete and water are mixed, and the slurry is formed and then solidified to obtain the concrete lightweight building block.
[0042] In the present invention, the curing may be static curing; the curing temperature is room temperature, the curing pressure is normal pressure; the curing time may be 7 to 30 days, and in a specific embodiment, may be 14 days or 21 days.
[0043] In the present invention, curing is also included before curing; the curing time can be 24 to 48 hours, the relative humidity can be 60 to 80%, and the temperature can be 25 to 30°C.
[0044] The present invention also provides the use of the reed fiber-based concrete described in the above technical solution, the reed fiber-based concrete prepared by the preparation method described in the above technical solution, the concrete lightweight block described in the above technical solution, or the concrete lightweight block prepared by the preparation method described in the above technical solution in building materials, fireproof materials or agricultural materials.
[0045] In the present invention, the building material can be an energy-saving building material; the fireproof material can be a fireproof door; and the agricultural material can be an intelligent agricultural material. The present invention does not have any special restrictions on the application process of the reed fiber-based concrete and the lightweight concrete blocks in building materials, fireproof materials or agricultural materials, and can be applied in a manner familiar to those skilled in the art.
[0046] In order to further illustrate the present invention, the reed fiber-based concrete, lightweight concrete blocks, and preparation methods and applications thereof provided by the present invention are described in detail below in conjunction with embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0047] Example 1
[0048] Reed chips with a moisture content of 18% were added to a 6% sodium hypochlorite / sodium hydroxide 1:2 mixed solution, and removed at 85°C for 3 hours to remove lignin and sugar, and then separated by hydrothermal microwave combined treatment for 10 minutes at a temperature of 120°C and a microwave frequency of 2500MHz, and dispersed by a hot mill to obtain reed fibers;
[0049] Weigh 400 parts of the above-mentioned pretreated reed fiber, 26 parts of calcium stearate and 1500 parts of silicate cement clinker, dry-mix and evenly obtain a mixture A; weigh 9.8 parts of manganese dioxide and 760 parts of water, stir and disperse, and evenly obtain a suspension B; add the above mixture A to the suspension B, and stir evenly at 35°C to obtain a slurry C; add 2 parts of a chelate complex of magnesium ion and 85% EVA emulsion to the slurry C to obtain a mixture D, wherein the mass percentage of magnesium ion is 0.6%; add 46 parts of 30% hydrogen peroxide to the mixture D, stir for 10s, and obtain a mixture E; pour the mixture E into a mold, cure it at a relative humidity of 65% and 25°C for 24h, then stand and cure for 3d at room temperature and pressure, and demold to obtain a reed fiber-based concrete porous lightweight building block.
[0050] Example 2
[0051] Reed fiber-based concrete porous lightweight building blocks were prepared according to the method shown in Example 1, except that the amount of the chelate of metal ions and organic polymers used was 6 parts.
[0052] Example 3
[0053] Reed fiber-based concrete porous lightweight building blocks were prepared according to the method shown in Example 1, except that the amount of the chelate of metal ions and organic polymers used was 10 parts.
[0054] Example 4
[0055] Reed fiber-based concrete porous lightweight building blocks were prepared according to the method shown in Example 1, except that the amount of the chelate of metal ions and organic polymers used was 14 parts.
[0056] Comparative Example 1
[0057] Reed fiber-based concrete porous blocks were prepared according to the method shown in Example 1, except that no chelate of metal ions and organic polymers was added.
[0058] Test Case
[0059] The performance of the reed fiber-based concrete porous lightweight blocks prepared in Examples 1 to 4 and Comparative Example 1 was tested according to GB / T 4111-2013, and the results are shown below.
[0060] Table 1 Performance test results of reed fiber-based porous concrete blocks obtained in Examples 1 to 4 and Comparative Example 1
[0061]
[0062] From the results in Table 1, it can be seen that compared with the reed fiber-based porous lightweight concrete blocks in the control example without adding chelates of metal ions and organic polymers, the water resistance and mechanical strength of the reed fiber-based porous lightweight concrete blocks prepared in Examples 1 to 4 of the present invention are significantly enhanced.
[0063] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.
Claims
1. A reed fiber-based concrete, characterized in that: The raw materials for preparing the reed fiber-based concrete include 300-500 parts of reed fiber, 1000-1600 parts of cement, 2-10 parts of manganese dioxide, 25-90 parts of foam stabilizer, 2-15.3 parts of chelate of metal ion and organic polymer and 45-80 parts of foaming agent in parts by weight.
2. The reed fiber-based concrete according to claim 1, characterized in that: The organic polymer is one or more of polyvinyl acetate, vinyl acetate-ethylene copolymer, polysaccharide and cellulose.
3. The reed fiber-based concrete according to claim 1, characterized in that: The metal ions are alkali metal ions and / or alkaline earth metal ions.
4. The reed fiber-based concrete according to claim 1, characterized in that: The foam stabilizer includes one or more of polyvinyl alcohol, sodium dodecylbenzene sulfonate and calcium stearate.
5. The reed fiber-based concrete according to claim 1, characterized in that: The foaming agent includes one or more of hydrogen peroxide, aluminum powder and baking soda.
6. The method for preparing reed fiber-based concrete according to any one of claims 1 to 5, characterized in that: The following steps are involved: The reed fiber-based concrete is obtained by mixing reed fiber, cement, manganese dioxide, a foam stabilizer, a chelate of metal ions and organic polymers, a foaming agent and water.
7. The preparation method according to claim 6, characterized in that: The reed fiber is a reed fiber bundle; the length of a single fiber in the reed fiber bundle is 12-36 mm, the diameter is 0.24-0.4 mm, and the aspect ratio is 50-90.
8. A lightweight concrete block, characterized in that: The material of the lightweight concrete block is the reed fiber-based concrete according to any one of claims 1 to 5 or the reed fiber-based concrete prepared by the preparation method according to any one of claims 6 or 7; the porosity of the lightweight concrete block is 60% to 90%, and the density is 0.2 to 0.6 g / cm 3 .
9. The method for preparing the lightweight concrete block according to claim 8, characterized in that: The following steps are involved: The reed fiber-based concrete and water are mixed, and the slurry is formed and then solidified to obtain the concrete lightweight building block.
10. Use of the reed fiber-based concrete according to any one of claims 1 to 5, the reed fiber-based concrete prepared by the preparation method according to claim 6 or 7, the lightweight concrete block according to claim 8 or the lightweight concrete block prepared by the preparation method according to claim 9 in building materials, fireproof materials or agricultural materials.