CN117735869A - Carbon nano tube reinforced magnesium silicate cementing material and preparation method thereof - Google Patents
Carbon nano tube reinforced magnesium silicate cementing material and preparation method thereof Download PDFInfo
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- CN117735869A CN117735869A CN202410193941.5A CN202410193941A CN117735869A CN 117735869 A CN117735869 A CN 117735869A CN 202410193941 A CN202410193941 A CN 202410193941A CN 117735869 A CN117735869 A CN 117735869A
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 96
- 239000000463 material Substances 0.000 title claims abstract description 95
- 239000002041 carbon nanotube Substances 0.000 title claims abstract description 88
- 229910021393 carbon nanotube Inorganic materials 0.000 title claims abstract description 88
- HCWCAKKEBCNQJP-UHFFFAOYSA-N magnesium orthosilicate Chemical compound [Mg+2].[Mg+2].[O-][Si]([O-])([O-])[O-] HCWCAKKEBCNQJP-UHFFFAOYSA-N 0.000 title claims abstract description 70
- 239000000391 magnesium silicate Substances 0.000 title claims abstract description 69
- 229910052919 magnesium silicate Inorganic materials 0.000 title claims abstract description 69
- 235000019792 magnesium silicate Nutrition 0.000 title claims abstract description 69
- 238000002360 preparation method Methods 0.000 title claims abstract description 15
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims abstract description 73
- 239000000395 magnesium oxide Substances 0.000 claims abstract description 51
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- 238000003756 stirring Methods 0.000 claims abstract description 36
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- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims abstract description 20
- 239000002002 slurry Substances 0.000 claims abstract description 19
- 230000000694 effects Effects 0.000 claims abstract description 16
- GCLGEJMYGQKIIW-UHFFFAOYSA-H sodium hexametaphosphate Chemical compound [Na]OP1(=O)OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])O1 GCLGEJMYGQKIIW-UHFFFAOYSA-H 0.000 claims abstract description 16
- 235000019982 sodium hexametaphosphate Nutrition 0.000 claims abstract description 16
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- 238000000034 method Methods 0.000 claims description 22
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- 239000000843 powder Substances 0.000 claims description 7
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- 229910000831 Steel Inorganic materials 0.000 claims description 6
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- 239000010959 steel Substances 0.000 claims description 6
- 239000002253 acid Substances 0.000 claims description 5
- 239000000706 filtrate Substances 0.000 claims description 5
- 230000007935 neutral effect Effects 0.000 claims description 5
- 238000001291 vacuum drying Methods 0.000 claims description 5
- 238000005406 washing Methods 0.000 claims description 5
- 239000002048 multi walled nanotube Substances 0.000 claims description 4
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- 229920002678 cellulose Polymers 0.000 description 5
- 238000005265 energy consumption Methods 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 description 4
- 230000015556 catabolic process Effects 0.000 description 4
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- DGVMNQYBHPSIJS-UHFFFAOYSA-N dimagnesium;2,2,6,6-tetraoxido-1,3,5,7-tetraoxa-2,4,6-trisilaspiro[3.3]heptane;hydrate Chemical compound O.[Mg+2].[Mg+2].O1[Si]([O-])([O-])O[Si]21O[Si]([O-])([O-])O2 DGVMNQYBHPSIJS-UHFFFAOYSA-N 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
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- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 2
- 239000004743 Polypropylene Substances 0.000 description 2
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
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- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 2
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 2
- 229910052943 magnesium sulfate Inorganic materials 0.000 description 2
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Abstract
The invention belongs to the field of cementing materials in the building material industry, and relates to a carbon nano tube reinforced magnesium silicate cementing material and a preparation method thereof, wherein the cementing material is prepared by taking active magnesium oxide, silica fume, carbon nano tubes and sodium hexametaphosphate as raw materials, and comprises the steps of pretreating the carbon nano tubes to obtain the carbon nano tubes with carboxylated surfaces; weighing raw materials according to a specific proportion, and dry-stirring MgO and silica fume for 2min; respectively preparing a carbon nano tube containing surface carboxylation, sodium hexametaphosphate, a silica fume dispersion system and a MgO dispersion system, and mixing and stirring to obtain slurry; and (5) forming and curing to obtain the carbon nano tube reinforced magnesium silicate gel material. The invention makes the pretreated carbon nano tube uniformly dispersed in the cementing material, and the pretreated carbon nano tube is tightly combined with the cementing particles, so that the overall stability of the material is improved, the bending strength and fracture toughness of the magnesium silicate-based material are enhanced, the retention rate of fiber reinforcement effect is improved, and the durability is improved.
Description
Technical Field
The invention relates to a carbon nano tube reinforced magnesium silicate cementing material and a preparation method thereof, belonging to the cementing material field of building material industry.
Background
In recent years, in the environment where the state advocates the sustainable development, the cement industry is regarded as the industry of high pollution, high emission and high consumption, and the traditional production mode of the cement industry is required to be improved, and the cement industry is advanced towards the direction of low energy consumption, low pollution and low emission. Magnesium-based cement is increasingly attracting attention and favor due to environmental protection characteristics such as low energy consumption and low carbon emission. With the economic development, a large amount of solid waste is generated in China every year, and the resource utilization of the solid waste is one of the fields with the most potential for reducing carbon emission. However, in terms of comprehensive utilization rate of solid waste resources, china does not reach the level of high-efficiency utilization of industrial solid waste resources.
The novel low-carbon cementing material with full solid waste has no carbon dioxide decomposition and high-temperature calcination links in the production process of the ordinary cement clinker, has no limestone ore exploitation process, has shorter production flow, has carbon emission of only 20% -30% of the ordinary cement, and has energy consumption of only about 35% of the conventional cement. If the solid waste is used for producing the novel low-carbon gel material, namely, the solid waste is used as a core, the solid waste is recycled in the fields of cooperative metallurgy, coal electricity, mining industry and the like, and the multi-component activity among the material components is utilized to cooperatively excite the material to prepare the low-carbon gel material which can be used as cement, so that the utilization rate of the solid waste can be effectively improved, the energy consumption and the carbon emission of the cement in the production process can be greatly reduced, and the pollution of the solid waste and the cement production to the ecological environment can be reduced.
The hydrated magnesium silicate cement is a new hydraulic cement which is newly developed in recent years, is prepared by mixing silica fume and light-burned magnesium oxide as raw materials and adding water, is abbreviated as M-S-H, and is a novel green cementing material with high commercial potential due to the ecological characteristics of low energy consumption, low pollution, low carbon burden, low alkalinity and the like, light weight, simple production process, excellent mechanical property and the like. However, the hydrated magnesium silicate cement has the defects of high brittleness, poor crack resistance, poor deformability and the like, and the short fiber is generally considered to be a method for effectively improving the mechanical strength, ductility and toughness of the cement, wherein the glass fiber is widely applied due to the characteristics of low cost, higher tensile strength, elastic modulus and the like. However, glass fibers are susceptible to corrosion in alkaline environments, so that the fiber reinforcing effect is reduced; polypropylene fibers and polyvinyl alcohol fibers are also commonly used to enhance cement properties, but organic fibers have poor stability in magnesium silicate alkaline environments, and excessive amounts of polypropylene fibers can also affect cement paste flowability. CN111646764a discloses a whisker modified hydrated magnesium silicate material, which mainly comprises magnesium oxide, silica fume, aggregate, sodium hexametaphosphate and basic magnesium sulfate whisker according to a specific proportion, wherein energy can be consumed between the basic magnesium sulfate whisker and a hydrated magnesium silicate material matrix through a friction mode after the raw materials are solidified and molded, so that crack generation and rapid expansion of fracture surfaces are retarded to a great extent, and the mechanical strength of the whisker modified hydrated magnesium silicate material after solidification and molding can be effectively improved; meanwhile, a framework is provided for the M-S-H gel, so that the shrinkage of the gel is reduced, and the problems of large water demand and large shrinkage deformation of the existing hydrated magnesium silicate cement are effectively solved. CN115716742a discloses a glass fiber reinforced hydrated magnesium silicate cement composite material, which comprises the following components in percentage by weight: 30-50 parts of light burned magnesia, 40-60 parts of silica fume, 90-120 parts of quartz sand, 50-60 parts of mixing water, 2-4 parts of sodium hexametaphosphate and 2-8 parts of glass fiber. The magnesium silicate hydrate cement is used as a base material, and glass fiber is used as a reinforcing material, so that the magnesium silicate hydrate cement has the characteristics of light weight, high strength and low shrinkage, and the defects of high brittleness, poor crack resistance and poor deformability of the existing magnesium silicate hydrate cement system are obviously overcome. CN116354644a discloses a magnesium silicate based cementing material performance modifier, which consists of a magnesium reinforcing agent, an organic dispersion solvent, an excitation catalyst and toughening reinforcing cellulose. The toughening and reinforcing cellulose consists of rhizobium cellulose and agrobacterium cellulose, and the adoption of the toughening and reinforcing cellulose can obviously enhance the flexural strength of the system, reduce the drying shrinkage of the system and effectively solve the defects of poor flexural strength and large drying shrinkage of the magnesium silicate-based cementing material. CN103539403a discloses a high-strength concrete composite material and a preparation method thereof, the concrete composite material comprises the following components in parts by weight: 100 parts of cement; 1-5 parts of fiber; 2-20 parts of silica fume; 1-20 parts of fly ash; 1-10 parts of composite rare earth; 10-200 parts of magnesium silicate particles; 140-200 parts of sand; 140-200 parts of crushed stone; 30-50 parts of water, and the prepared product has strong crack resistance, small crack width after being loaded, long-term durability, and improves the interaction of composite concrete, avoids the generation of temperature cracks, and ensures the strength, freezing resistance and impermeability of the concrete. CN111958760a discloses a bamboo pulp cellulose fiber/hydrated magnesium silicate based composite material, which is prepared from 4-16 parts of bamboo pulp cellulose fiber, 33.6-55 parts of magnesium oxide and 37.8-60 parts of silica fume. The bamboo pulp cellulose fiber is used as the reinforcing phase of the magnesium silicate-based composite material, so that the bending strength and fracture toughness of the composite material are improved, and meanwhile, the pH value of the magnesium silicate matrix is lower than that of the silicate cement matrix, so that the influence of alkalinity on fiber degradation can be reduced, the fiber can play a longer reinforcing effect in the composite material, and the durability is improved. Although the introduction of various fiber materials in the magnesium silicate cement can improve the cement performance to a certain extent, the fibers are mostly mixed by simple stirring in the magnesium silicate cementing material, so that the fibers cannot be well distributed in the cement material, and the improvement of the material performance and the maintenance of the long-term stability of the fibers in the cement are not facilitated.
Therefore, there is a need to develop a fiber modification method for improving the mechanical properties of magnesium silicate gel materials and stably existing in the gel materials for a long time and uniformly dispersing, and a modified magnesium silicate low-carbon gel material, which has better economic benefit and environmental protection value if a large amount of industrial solid waste materials are used and the use of cement clinker is reduced or eliminated.
Disclosure of Invention
In order to solve the defects in the prior art, the invention provides a carbon nano tube reinforced magnesium silicate cementing material and a preparation method thereof, wherein the surface of the carbon nano tube is carboxylated by pretreatment of the carbon nano tube, so that the surface of the carbon nano tube is attached to a certain amount of negative charge surface, the magnesium silicate cementing material usually presents positive charge, and after the pretreated carbon nano tube is mixed with a magnesium silicate cementing material precursor dispersion system, the carbon nano tube and the cementing material precursor are uniformly dispersed by stirring and an internal electric field, thereby reducing agglomeration and improving the stability of the cementing material system.
The invention aims at providing a preparation method of a carbon nano tube reinforced magnesium silicate cementing material, which comprises the following steps: (1) pretreatment of carbon nanotubes: taking carbon nano tube powder, and putting H with the molar ratio of 1:3-1:5 into the powder 2 SO 4 :HNO 3 Dispersing the carbon nano tube in a mixed acid solution for 20min by ultrasonic, placing the carbon nano tube in deionized water for 30min, carrying out suction filtration, repeatedly washing the carbon nano tube with deionized water until filtrate is neutral, and carrying out vacuum drying at 40 ℃ for 72h to obtain the carbon nano tube with carboxylated surface;
(2) Weighing raw materials, and mixing: respectively weighing active MgO and silica fume according to the mass ratio of 1:1-4:1, weighing the carbon nano tube with carboxylated surface according to 1-10% of the total mass of MgO and silica fume, weighing sodium hexametaphosphate according to 0.5-1.5% of the total mass of MgO and silica fume, and weighing deionized water according to 40-60% of the total mass of MgO and silica fume; respectively placing the weighed active MgO and silica fume in a paste mixer to dry and stir for 2min for later use;
(3) Dividing deionized water in the step (2) into two parts averagely, wherein the first part is the carbon nano tube pretreated in the step (1) under stirring, and sequentially adding sodium hexametaphosphate and silica fume under stirring after uniform dispersion to obtain a dispersion system A; adding active MgO into the other part under stirring, fully stirring to obtain a dispersion system B, adding the B into the dispersion system A, and continuously stirring for 20min to obtain slurry;
(4) And (3) pouring the slurry obtained in the step (3) into a mould rapidly, and obtaining the carbon nano tube reinforced magnesium silicate gel material through molding and curing.
As a preferable scheme, the carbon nanotube can be at least one of a single-wall carbon nanotube and a multi-wall carbon nanotube, the ultrasonic power in the pretreatment of the carbon nanotube is 40-100 KHz, and the ultrasonic treatment time is 10-100 min. The surface of the carbon nano tube is carboxylated by carrying out specific pretreatment on the carbon nano tube, the surface of the carbon nano tube is attached to a certain amount of negative charge surface, and the magnesium silicate cementing material usually presents positive charge, after the pretreated carbon nano tube is mixed with a magnesium silicate cementing material precursor dispersion system, the carbon nano tube can be uniformly dispersed in the cementing material system by stirring and electrostatic action among internal particles, so that the agglomeration of the carbon nano tube is reduced, and the stability of the cementing system is better maintained. The parameters related to the pretreatment of the carbon nanotubes can be adjusted according to actual needs, so that the stable surface carboxylation of the carbon nanotubes is suitable.
The active MgO used in the invention is light burned magnesia with an active index of 70-95%, and the main components are MgO:97.5wt%, siO2:0.56wt% of CaO:1.93wt% and the balance of other impurities, and the purity of the magnesia in the raw material is higher. The activity of magnesium oxide is measured by reference to the hydration method in the WB/T1019-2002 Standard of light burned magnesium oxide for magnesite productsThe method is a method for measuring MgO activity accepted by the magnesite industry, the activity index of magnesium oxide in the light burned magnesium oxide used in the invention is 70-95%, and the method belongs to high-activity magnesium oxide. The higher the activity of magnesium oxide, the more rapid the active MgO reacts and generates a large amount of Mg (OH) at the beginning of the reaction 2 The method comprises the steps of carrying out a first treatment on the surface of the The reaction solution contains enough Mg 2+ And OH (OH) - To promote Mg (OH) 2 And M-S-H gel formation, mg (OH) being present in the system at the same time 2 And M-S-H gel, the reaction rate of MgO gradually decreases as the reaction proceeds, resulting in the formation of Mg (OH) in the latter stage of the reaction 2 The reaction to form M-S-H gel is stopped and the reaction to form M-S-H gel is continued so that MgO-SiO 2 -H 2 Mg (OH) in O-gel systems 2 The content of the M-S-H gel is increased and then decreased, and the chemical stability of the M-S-H gel is higher than that of Mg (OH) 2 Thus, the reaction ratio for forming M-S-H gel forms Mg (OH) 2 More readily occurring and to a greater extent, in addition to Mg (OH) 2 Can be further reacted with silica fume to form M-S-H gel, so that Mg (OH) in the later period of the reaction 2 The content of (2) is continuously reduced.
In the invention, the active materials MgO and silica fume are weighed and then are dried and stirred for 2 minutes in a paste mixer, so that the active materials can be further activated, and the subsequent hydration reaction can be conveniently and rapidly carried out. For the addition sequence of each material in the preparation process of the cementing material, the applicant finds that different addition sequences can influence the mechanical properties of the magnesium silicate cementing material, and the applicant finds that the bending strength and fracture toughness of the cementing material can be improved to a certain extent by adopting the way of respectively preparing MgO dispersion liquid and silica fume dispersion liquid and dispersing other raw materials together with the silica fume through a large number of experiments.
For the preparation of the cement molding sample, a suitable mold and treatment process can be selected according to practical test requirements, for example, the mold is a steel mold with the dimensions of 160 mm ×40 mm ×8× 8 mm. The molding is rapid molding, comprising the following steps: vibrating for 20 seconds to remove bubbles, carrying out vacuum suction filtration until the surface of the slurry sample is hardened, keeping the vacuum degree between 60 and 80kPa during suction filtration, covering a layer of polyethylene film on the surface of the die to avoid water loss, curing for 5 hours, and demolding. Curing is carried out by a method combining steam curing and standard curing. And the steam curing is to cure the molded sample in a steam curing box at 60-80 ℃ for 2 d, and take out the sample and cool the sample to room temperature. The standard curing is to cure the molded sample for 28 days under the constant temperature and humidity environment condition of 22+/-1 ℃ and the relative humidity of 80% -90%. For obtaining the performance of the cementing material, test pieces of 28 days old can be tested according to the method of cement mortar strength test method (GB/T17671-1999).
Another object of the present invention is to provide a carbon nanotube reinforced magnesium silicate gel material composed of surface carboxylated carbon nanotubes and hydrated magnesium silicate. The carboxylation treatment of the surface of the carbon nano tube is simple in operation, the technology is relatively mature, the carbon nano tube subjected to the treatment can be more uniformly dispersed in the cementing material, and is anchored with the cementing particles through electric charge attraction, so that the combination is more compact, and the overall stability of the material is improved.
The carbon nano tube reinforced magnesium silicate cementing material provided by the invention can replace the current common cement material to be widely used in building materials, and has the following advantages: the carbon nano tube is used for internal filling, the strength of the material is high, the weight of the magnesium oxide per unit volume is light compared with that of the conventional cement, and meanwhile, the alkalinity of the cementing system is lower. The material of the invention is suitable for manufacturing cementing material products, wall materials, grouting materials, glass fiber reinforced cement products and the like. Can replace part of uses of silicate series cement to prepare mortar and concrete.
Compared with the prior art, the beneficial effects of the technical scheme are as follows:
the invention prepares the magnesium silicate system low-carbon gel material based on light burned magnesia and solid waste silica fume, and the magnesium silicate system low-carbon gel material is hydrated with active MgO and reacts with SiO 2 The magnesium silicate system cementing material is prepared by the action of the method, the whole process realizes the reutilization of solid waste silica fume, greatly reduces the cost of raw materials of the whole process, and meets the requirement of sustainable development; the prepared magnesium silicate system cementing material has excellent performance, can replace part of uses of silicate series cements, and truly realizes comprehensive utilization and even high-efficiency utilization of resources.
According to the preparation method, the pretreated carbon nanotubes are uniformly dispersed in the cementing material and are tightly combined with the cementing particles, so that the overall stability of the material is improved, the bending strength and fracture toughness of the magnesium silicate-based material are enhanced, and meanwhile, compared with other organic fibers, the influence of alkalinity on fiber degradation can be effectively reduced by using the carbon nanotubes, the retention rate of fiber reinforcement effect is improved, and the durability is improved. The carbon nano tube reinforced magnesium silicate cementing material obtained by the method adopts the carbon nano tube as a reinforcing phase, so that the mechanical property of the magnesium silicate cementing material is improved, and meanwhile, the interface bonding between the carbon nano tube and a cementing material matrix is also improved. Meanwhile, the magnesium silicate system cementing material of the invention further ensures that the initial reaction speed is high and the structure grows well by designing the curing conditions, so that the whole cement-based material has good molding effect and better mechanical property.
Detailed Description
In order to make the technical problems solved, the technical solutions adopted and the technical effects achieved by the present invention more clear, the technical solutions of the embodiments of the present invention will be described in further detail below, and it is obvious that the described embodiments are only some embodiments of the present invention, but not all embodiments. All other embodiments, based on the embodiments of the invention, which a person skilled in the art would obtain without making any inventive effort, are within the scope of the invention.
It is noted that reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.
The experimental methods in the following examples are conventional methods unless otherwise specified. Materials, reagents and the like used in the examples described below are commercially available unless otherwise specified.
Example 1
The preparation method of the carbon nano tube reinforced magnesium silicate cementing material comprises the following steps of: (1) 300g of single-walled carbon nanotube powder is taken and put into H with the mol ratio of 1:3 2 SO 4 :HNO 3 Dispersing in mixed acid solution for 20min under ultrasonic power of 40KHz, placing in deionized water for 30min, suction filtering, repeatedly washing with deionized water until filtrate becomes neutral, and vacuum drying at 40deg.C for 72 hr to obtain surface carboxylated carbon nanotube;
(2) Weighing 600g of light burned magnesium oxide with an activity index of 70-95%, 400g of silica fume, 10g of carbon nano tubes with carboxylated surfaces, 5g of sodium hexametaphosphate and 600mL of deionized water, and respectively placing the weighed active MgO and the silica fume in a paste mixer for dry stirring for 2min for later use;
(3) Respectively placing 300mL of deionized water in two containers, sequentially adding 10g of carbon nano tube with carboxylated surface, 5g of sodium hexametaphosphate and 400g of silica fume into one container under stirring, and uniformly dispersing to obtain a dispersion system A; adding 600g of light-burned magnesium oxide into the other part of deionized water under stirring, fully stirring to obtain a dispersion system B, adding the B into the dispersion system A, and continuously stirring for 20min to obtain slurry;
(4) And (3) rapidly pouring the obtained slurry into a steel mold with the size of 160 mm multiplied by 40 mm multiplied by 8 mm, vibrating for 20 seconds to remove bubbles, simultaneously carrying out vacuum suction filtration until the surface of the slurry sample is hardened, keeping the vacuum degree between 60 and 80kPa during suction filtration, covering a layer of polyethylene film on the surface of the mold to avoid water loss, curing for 5 hours, demolding, then placing the formed sample into a steam curing box with the temperature of 60-80 ℃ for curing for 2 d, taking out the sample, cooling to room temperature, and then placing the formed sample into a constant temperature and constant humidity environment with the temperature of 22+/-1 ℃ and the relative humidity of 80% -90%, and curing for 28 days to obtain the carbon nano tube reinforced magnesium silicate gel material. The detection shows that the flexural strength of the magnesium silicate cementing material is 12Mpa and the fracture toughness is 1.5KJ/m 2 After 100 days of aging test, the flexural strength is 11.8Mpa, and the fracture toughness is 1.47KJ/m 2 。
Example 2
The preparation method of the carbon nano tube reinforced magnesium silicate cementing material comprises the following steps of: (1) 300g of multi-wall carbon nano tube powder is taken and put into H with the mol ratio of 1:5 2 SO 4 :HNO 3 Dispersing in mixed acid solution for 20min under ultrasonic power of 40KHz, placing in deionized water for 30min, suction filtering, repeatedly washing with deionized water until filtrate becomes neutral, and vacuum drying at 40deg.C for 72 hr to obtain surface carboxylated carbon nanotube;
(2) Weighing 800g of light burned magnesium oxide with an activity index of 70-95%, 400g of silica fume, 120g of carbon nano tube with carboxylated surface, 18g of sodium hexametaphosphate and 480mL of deionized water, and respectively placing the weighed active MgO and silica fume in a paste mixer for dry stirring for 2min for later use;
(3) Respectively placing 240mL of deionized water in two containers, sequentially adding 120g of carbon nano tube with carboxylated surface, 18g of sodium hexametaphosphate and 400g of silica fume into one container under stirring, and uniformly dispersing to obtain a dispersion system A; adding 800g of light-burned magnesium oxide into the other part of deionized water under stirring, fully stirring to obtain a dispersion system B, adding the B into the dispersion system A, and continuously stirring for 20min to obtain slurry;
(4) And (3) rapidly pouring the obtained slurry into a steel mold with the size of 160 mm multiplied by 40 mm multiplied by 8 mm, vibrating for 20 seconds to remove bubbles, simultaneously carrying out vacuum suction filtration until the surface of the slurry sample is hardened, keeping the vacuum degree between 60 and 80kPa during suction filtration, covering a layer of polyethylene film on the surface of the mold to avoid water loss, curing for 5 hours, demolding, then placing the formed sample into a steam curing box with the temperature of 60-80 ℃ for curing for 2 d, taking out the sample, cooling to room temperature, and then placing the formed sample into a constant temperature and constant humidity environment with the temperature of 22+/-1 ℃ and the relative humidity of 80% -90%, and curing for 28 days to obtain the carbon nano tube reinforced magnesium silicate gel material. The detection shows that the flexural strength of the magnesium silicate cementing material is 11.4Mpa and the fracture toughness is 1.7KJ/m 2 After 100 days of aging test, the bending strength is 11.4Mpa, and the fracture isToughness of 1.69KJ/m 2 。
Example 3
The preparation method of the carbon nano tube reinforced magnesium silicate cementing material comprises the following steps of: (1) 300g of multi-wall carbon nano tube powder is taken and put into H with the mol ratio of 1:4 2 SO 4 :HNO 3 Dispersing in mixed acid solution for 20min under ultrasonic power of 40KHz, placing in deionized water for 30min, suction filtering, repeatedly washing with deionized water until filtrate becomes neutral, and vacuum drying at 40deg.C for 72 hr to obtain surface carboxylated carbon nanotube;
(2) Weighing 500g of light burned magnesium oxide with an activity index of 70-95%, 400g of silica fume, 45g of carbon nano tube with carboxylated surface, 9g of sodium hexametaphosphate and 440mL of deionized water, and respectively placing the weighed active MgO and silica fume in a paste mixer for dry stirring for 2min for later use;
(3) Respectively placing 220mL of deionized water in two containers, sequentially adding 45g of carbon nano tube with carboxylated surface, 9g of sodium hexametaphosphate and 400g of silica fume into one container under stirring, and uniformly dispersing to obtain a dispersion system A; adding 500g of light-burned magnesium oxide into the other part of deionized water under stirring, fully stirring to obtain a dispersion system B, adding the B into the dispersion system A, and continuously stirring for 20min to obtain slurry;
(4) And (3) rapidly pouring the obtained slurry into a steel mold with the size of 160 mm multiplied by 40 mm multiplied by 8 mm, vibrating for 20 seconds to remove bubbles, simultaneously carrying out vacuum suction filtration until the surface of the slurry sample is hardened, keeping the vacuum degree between 60 and 80kPa during suction filtration, covering a layer of polyethylene film on the surface of the mold to avoid water loss, curing for 5 hours, demolding, then placing the formed sample into a steam curing box with the temperature of 60-80 ℃ for curing for 2 d, taking out the sample, cooling to room temperature, and then placing the formed sample into a constant temperature and constant humidity environment with the temperature of 22+/-1 ℃ and the relative humidity of 80% -90%, and curing for 28 days to obtain the carbon nano tube reinforced magnesium silicate gel material. The test shows that the flexural strength of the magnesium silicate cementing material is 11.7Mpa, and the fracture toughness is 1.57KJ/m 2 After 100 days of aging test, the anti-bending strength of the alloy is highThe degree of fracture is 11.68Mpa, and the fracture toughness is 1.56KJ/m 2 。
Comparative example 1
The preparation method of the carbon nano tube reinforced magnesium silicate cementing material comprises the following steps of: (1) Weighing 500g of light burned magnesium oxide with an activity index of 70-95%, 400g of silica fume, 45g of single-walled carbon nanotubes, 9g of sodium hexametaphosphate and 440mL of deionized water, and respectively placing the weighed active MgO and the silica fume in a paste mixer for 2min for later use;
(2) Respectively placing 220mL of deionized water in two containers, sequentially adding 45g of carbon nano tube, 9g of sodium hexametaphosphate and 400g of silica fume into one container under stirring, and uniformly dispersing to obtain a dispersion system A; adding 500g of light-burned magnesium oxide into the other part of deionized water under stirring, fully stirring to obtain a dispersion system B, adding the B into the dispersion system A, and continuously stirring for 20min to obtain slurry;
(3) And (3) rapidly pouring the obtained slurry into a steel mold with the size of 160 mm multiplied by 40 mm multiplied by 8 mm, vibrating for 20 seconds to remove bubbles, simultaneously carrying out vacuum suction filtration until the surface of the slurry sample is hardened, keeping the vacuum degree between 60 and 80kPa during suction filtration, covering a layer of polyethylene film on the surface of the mold to avoid water loss, curing for 5 hours, demolding, then placing the formed sample into a steam curing box with the temperature of 60-80 ℃ for curing for 2 d, taking out the sample, cooling to room temperature, and then placing the formed sample into a constant temperature and constant humidity environment with the temperature of 22+/-1 ℃ and the relative humidity of 80% -90%, and curing for 28 days to obtain the carbon nano tube reinforced magnesium silicate gel material. The test shows that the flexural strength of the magnesium silicate cementing material is 8.5Mpa and the fracture toughness is 1.07KJ/m 2 After 100 days of aging test, the flexural strength is 7.3MPa, and the fracture toughness is 9.64KJ/m 2 。
As can be seen from the comparison of the data, the magnesium silicate system cementing material prepared by the invention realizes the tighter combination of the carbon nano tube and the cementing particles by introducing the specially treated carbon nano tube and uniformly dispersing the specially treated carbon nano tube in the cementing material, can improve the overall stability of the material, has no obvious degradation of the performance of the magnesium silicate cement product after long-time aging, can strengthen the bending strength and the fracture toughness of the magnesium silicate system cementing material, effectively reduce the influence of alkalinity on the degradation of fibers, improve the retention rate of fiber reinforcement effect and improve the durability.
The foregoing describes a carbon nanotube reinforced magnesium silicate gel material and a method for preparing the same, and the foregoing describes the invention in further detail in connection with specific preferred embodiments, and it is not to be construed that the invention is limited to the specific embodiments. For those skilled in the art, the architecture of the invention can be flexible and changeable without departing from the concept of the invention, and serial products can be derived. But a few simple derivatives or substitutions should be construed as falling within the scope of the invention as defined by the appended claims.
Claims (10)
1. The preparation method of the carbon nano tube reinforced magnesium silicate cementing material is characterized by comprising the following steps of: (1) pretreatment of carbon nanotubes: taking carbon nano tube powder, and putting H with the molar ratio of 1:3-1:5 into the powder 2 SO 4 :HNO 3 Dispersing the carbon nano tube in a mixed acid solution for 20min by ultrasonic, placing the carbon nano tube in deionized water for 30min, carrying out suction filtration, repeatedly washing the carbon nano tube with deionized water until filtrate is neutral, and carrying out vacuum drying at 40 ℃ for 72h to obtain the carbon nano tube with carboxylated surface;
(2) Weighing raw materials, and mixing: respectively weighing active MgO and silica fume according to the mass ratio of 1:1-4:1, weighing the carbon nano tube with carboxylated surface according to 1-10% of the total mass of MgO and silica fume, weighing sodium hexametaphosphate according to 0.5-1.5% of the total mass of MgO and silica fume, and weighing deionized water according to 40-60% of the total mass of MgO and silica fume; respectively placing the weighed active MgO and silica fume in a paste mixer to dry and stir for 2min for later use;
(3) Dividing deionized water in the step (2) into two parts averagely, wherein the first part is the carbon nano tube pretreated in the step (1) under stirring, and sequentially adding sodium hexametaphosphate and silica fume under stirring after uniform dispersion to obtain a dispersion system A; adding active MgO into the other part under stirring, fully stirring to obtain a dispersion system B, adding the B into the dispersion system A, and continuously stirring for 20min to obtain slurry;
(4) And (3) pouring the slurry obtained in the step (3) into a mould rapidly, and obtaining the carbon nano tube reinforced magnesium silicate gel material through molding and curing.
2. The method for preparing the carbon nanotube reinforced magnesium silicate gel material according to claim 1, wherein the carbon nanotubes are at least one of single-walled carbon nanotubes and multi-walled carbon nanotubes, and the ultrasonic power is 40-100 khz.
3. The method for preparing a carbon nanotube reinforced magnesium silicate gel material according to claim 1, wherein the active MgO is light burned magnesium oxide with an activity index of 70 to 95%.
4. The method of claim 1, wherein the mold in step (4) is a steel mold having dimensions 160 mm ×40× 40 mm ×8× 8 mm.
5. The method for preparing a carbon nanotube-reinforced magnesium silicate gel material according to claim 1, wherein the forming in step (4) is rapid forming, comprising the steps of: vibrating for 20 seconds to remove bubbles, carrying out vacuum suction filtration until the surface of the slurry sample is hardened, keeping the vacuum degree between 60 and 80kPa during suction filtration, covering a layer of polyethylene film on the surface of the die to avoid water loss, curing for 5 hours, and demolding.
6. The method for preparing the carbon nanotube reinforced magnesium silicate gel material according to claim 1, wherein the curing in the step (4) is performed by a combination of steam curing and standard curing.
7. The method for preparing a carbon nanotube reinforced magnesium silicate gel material according to claim 6, wherein the steam curing is to put a molded sample in a steam curing box at 60-80 ℃ for curing 2 d, and take out the sample and cool the sample to room temperature.
8. The method for preparing a carbon nanotube reinforced magnesium silicate gel material according to claim 6, wherein the standard curing is to cure the molded sample for 28 days under the constant temperature and humidity environment conditions of 22+/-1 ℃ and relative humidity of 80% -90%.
9. The carbon nano tube reinforced magnesium silicate cementing material is characterized by comprising surface carboxylated carbon nano tubes and hydrated magnesium silicate.
10. Use of the carbon nanotube-reinforced magnesium silicate gel material according to claim 9 in building materials.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009099640A1 (en) * | 2008-02-08 | 2009-08-13 | Northwestern University | Highly-dispersed carbon nanotube-reinforced cement-based materials |
| CN112592144A (en) * | 2020-12-29 | 2021-04-02 | 汪峻峰 | Corrosion-resistant concrete for offshore sewage pipeline and preparation method thereof |
| KR20210067832A (en) * | 2019-11-29 | 2021-06-08 | 단국대학교 산학협력단 | Carbon Nanotube Intermixed Cement and preparation method thereof |
| CN115772022A (en) * | 2022-12-01 | 2023-03-10 | 大连理工大学 | Modified magnesium cement and preparation method thereof |
-
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- 2024-02-21 CN CN202410193941.5A patent/CN117735869A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009099640A1 (en) * | 2008-02-08 | 2009-08-13 | Northwestern University | Highly-dispersed carbon nanotube-reinforced cement-based materials |
| KR20210067832A (en) * | 2019-11-29 | 2021-06-08 | 단국대학교 산학협력단 | Carbon Nanotube Intermixed Cement and preparation method thereof |
| CN112592144A (en) * | 2020-12-29 | 2021-04-02 | 汪峻峰 | Corrosion-resistant concrete for offshore sewage pipeline and preparation method thereof |
| CN115772022A (en) * | 2022-12-01 | 2023-03-10 | 大连理工大学 | Modified magnesium cement and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| 夏正兵等: "《建筑工程材料与检测》", 31 January 2021, 南京东南大学出版社, pages: 72 * |
| 李兆恒;李伟;韦江雄;余其俊;: "六偏磷酸钠分散剂和聚羧酸减水剂对硅镁胶凝材料水化进程的影响", 新型建筑材料, no. 07, 25 July 2018 (2018-07-25) * |
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