CN102943306A - Calcium carbonate whisker synthesizing and modified integrating method based on sol-gel method - Google Patents
Calcium carbonate whisker synthesizing and modified integrating method based on sol-gel method Download PDFInfo
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Abstract
The invention belongs to the technical field of whisker synthesizing and relates to a calcium carbonate whisker synthesizing and modified integrating method based on a sol-gel method. The method includes that first, a sol-gel method is used for synthesizing calcium carbonate whisker, and during synthesizing, a surface modifier is added for modifying the calcium carbonate whisker; then after modification, the calcium carbonate whisker is filtered, washed and dried to obtain a calcic intermediate; and finally, the calcic intermediate is calcined at the high temperature not less than 500 DEG C for 90-120 mins to obtain the calcium carbonate whisker. Compared with the prior art, the method is wide in raw material resources, low in cost, capable of finishing modification and synthesizing integrally, simple in process and suitable for large-scale production. Industrial production can be achieved. The prepared calcium carbonate whisker is high in purity, good in crystal form, large in long diameter, good in quality and dispersing performance in cement base materials, strong in binding power with a base body and capable of improving base body performance remarkably.
Description
Technical field
The invention belongs to the whisker synthesis technical field, relate to the synthetic and modification integral method of a kind of calcium carbonate crystal whisker based on sol-gel method.
Background technology
Along with the development of crystal synthesis technique, various inorganic mineral crystal whisker materials begin to be widely used in the enhancing of the matrixes such as polymkeric substance, pottery and toughness reinforcing, and effect is remarkable.
Calcium carbonate crystal whisker as a kind of take cheap calcium carbonate as starting material, by manual control, with the shape of monocrystalline form growth be similar to staple fibre and size much smaller than staple fibre must the shape single crystal.Its strength and modulus is close to the theoretical value of perfect crystal material key mapping intensity, have high strength, high-modulus, good heat-resisting and heat-proof quality, have the dual compound action of fiber and mineral fine powder concurrently, demonstrate excellent physicochemical property and mechanical property, become desirable cement based strongthener.The development that calcium carbonate crystal whisker is applied to New Building Materials will have a lot of advantages, can realize strengthening toughness reinforcing target, significantly improve the over-all properties of enhancing system.
At present, calcium carbonate crystal whisker is as a kind of inorganic mineral primitive fiber, and the research that utilizes its high fiber number, high strength, high-modulus and good thermostability etc. to strengthen toughness reinforcing cement-based material also is in the starting stage.Calcium carbonate crystal whisker is owing to have ultra-fine size, and surface energy is larger, assembles easily agglomeratingly, forms with coacervate some linkage interfaces and larger-size; Thereby cause its dispersed bad in matrix material, operate bad meeting and bring out " whisker toxicity ", make the performance of matrix material not rise counter falling, when being applied to cement-based material, also exist obvious shortcoming.There is agglomeration in calcium carbonate crystal whisker when using in cement-based material, affected its improvement to Microstructure of Cement-based Material.Effectively modification can reduce the surface energy of whisker, reduces the agglomeration power between calcium carbonate granule, improves its dispersiveness and dispersion stabilization in matrix, reduces by two alternate interfacial tensions, improve and base-material between bonding force, thereby improve the performance of matrix material.As seen, in order to bring into play the unique mechanical properties of calcium carbonate crystal whisker, it being carried out surface modification, is assistant officer's problem to be solved.
Simultaneously, in the three large mechanism (crackle bridge joint, crack deflection, whiosker pullout) of calcium carbonate crystal whisker strengthening and toughening cement matrix, whiosker pullout accounts for dominant advantage, and during most of whiosker pullout, the whisker smooth surface, adhesive tape cement based slurry is not arranged, illustrate that the cohesive force between calcium carbonate crystal whisker and cement based is not enough.If can make the whiosker pullout phenomenon that accounts for dominant advantage become whisker and pull off phenomenon by increasing both cohesive actions to the modification of whisker or the mode of admixture polymkeric substance, enhancement that then can more effective performance whisker.
At present, the synthetic method of calcium carbonate crystal whisker mainly contains following several:
(1) carbonation method
Carbonation method is at present domestic and international most study, also is comparatively ripe a kind of method.By to Ca (OH)
2Pass into CO in the water slurry
2Gas is realized, at Ca (OH)
2In the slurry, add in advance the needle-like calcium carbonate crystal seed or be conducive to crystal along phosphoric acid based compound, the Mg of one-dimensional square to growth
2+The chemical additives such as salt.By control Ca (OH)
2The concentration of slurry, temperature of reaction and CO
2The gas liquid reaction condition carbonate synthesis calcium pyroborates such as the speed that passes into of gas.Be similar to the gas-liquid system of industrial synthetic light calcium carbonate, therefore this method of person is also arranged is the gas-liquid synthesis method.It generally is with MgCl that carbonation method prepares calcium carbonate crystal whisker
2Or the phosphoric acid based compound makes the crystallization mode of calcium carbonate take aragonitic as main as crystal type promoting reagent.Phosphoric acid salt is as crystal type promoting reagent, in reaction process with Ca (OH)
2Reaction generates CaHPO
4, CaHPO then
4Induce it to be grown to the aragonitic whisker as the crystallization nuclei of calcium carbonate.
The advantage of this method is that technique is simple, and easily-controlled operation easily realizes industrialization; The recyclable recycling of magnesium salts, no coupling product generates; Raw material sources are extensive, and cost is low; Constant product quality.Maximum deficiency be need to be stricter temperature of reaction and long reaction times, could obtain the higher preparation of aragonite whisker of content, otherwise will be mixed with the higher Mg of content (OH) in the calcium carbonate crystal whisker
2Impurity.
(2) soluble calcium salt and manufacture of carbonates method
Being the metathesis preparation method, is the carbonate solution of solubility and the reaction between solubility (or microsolubility) calcium salt soln.General water-soluble Ca salt and carbonate solution reaction always generate calcite, and the synthetic needs of aragonitic whisker are strictly controlled the synthesis conditions such as temperature of reaction, pulp density, reaction times, stirring intensity.The greatest weakness of this method is exactly that the concentration of reactant can not be too high.If wanting that soluble carbonate salt solution with higher concentration joins reacts the preparation calcium carbonate crystal whisker in the solubility calcium salts solution, difficulty is larger.In order to improve the concentration of reactant, often need in reaction system, to add various chemical additives.In addition, this method can affect purity and the homogeneity of calcium carbonate crystal whisker owing to the heterogeneity of strength of solution, temperature.
(3) Ca (HCO
3)
2Preparation method
This method is to utilize Ca (HCO
3)
2The method of aqueous solution heating prepare calcium carbonate crystal whisker, reaction needed is strictly controlled temperature of reaction and stirring velocity etc.The temperature of reaction of this method and reaction times are easy to control, and is easy and simple to handle, overcome to a certain extent the defective of carbonation method and double decomposition.But this preparation method's energy consumption is large, and the length-to-diameter ratio of gained calcium carbonate crystal whisker is undesirable, and its productive rate or purity are all unsatisfactory, so follow-up study is very few.
(4) urea water solution
The urea water solution is to utilize hydrolysis of urea to slowly release CO
3 2-, reduce the synthetic degree of supersaturation of aragonite, generally use soluble calcium salt (CaCl
2Or Ca (NO
3)
2Deng) as the calcium source, CO
3 2-Formation speed decide with hydrolysis of urea speed, so the pattern of calcium carbonate crystal whisker and size ratio are easier to control.The advantage of this method is CO
3 2-Generation speed be subjected to the control of hydrolysis of urea speed and constant, so can generate the aragonite phase calcium carbonate crystal whisker of homogeneous.Shortcoming is amount of urea large (is calcium salt consumption 3 times), and cost is high, unsuitable and industrial production.And need at constant high temperature (110 ℃) so carry out large, the dangerous height of energy consumption under the condition of high voltage.
(5) sol-gel method
Sol-gel method is a kind of brand-new material preparation method, belongs to a kind of of wet chemistry method (comprising chemical coprecipitation, hydrothermal method, microemulsion method etc.).Sol-gel technique is with organometallics, metal inorganic compound or above-mentioned both mixtures, through the process of hydrolytie polycondensation, and gradually gelation and carry out respective handling, and obtain the novel process of oxide compound or other compounds.This method is under liquid phase state, the raw materials such as liquid chemical reagent (or be dissolved in solvent with powder) is evenly mixed, and carry out the chemical reactions such as a series of hydrolysis, condensation (polycondensation), forms stable transparent lyosol system in solution; Through ageing, lentamente polymerization between the micelle of colloidal sol forms three-dimensional polymer or particle space network take presoma as skeleton, is full of the solvent that loses flowability in the network, Here it is gel; Gel is sloughed solvent therebetween, and is become a kind of xerogel or aerogel with porous space structure through super-dry; At last, prepare required material through sintering curing.
About the surface modification of calcium carbonate crystal whisker, be by physics or chemical process with surface treatment agent absorption or reaction on the surface of calcium carbonate, form coating, make its surface active, thereby improve the surface property of calcium carbonate.At present to the study on the modification of calcium carbonate crystal whisker seldom, most of or with reference to the surface modifying method of lightweight and water-ground limestone, this has all been carried out a large amount of research in external, modification processing method commonly used has: (1) polymer overmold is processed; (2) coupling agent treatment (titanic acid ester, Aluminate, phosphoric acid ester, silane coupling agent); (3) tensio-active agent is processed (anionic, cationic, non-ionic type); (4) inorganics is processed (polyphosphoric acid, aluminium hydroxide etc.).
About the synthetic document of calcium carbonate crystal whisker:
Chinese patent: a kind of method of controlling shape and appearance of calcium carbonate, the patent No.: 200610023337,2006-1-16. Tongji University.This patent is characterised in that: the first step: middle is immobilized liquid membrane, about phenanthroline is dissolved in the chloroform for being equipped with of isolated system of solution phase, make the Liquid Membrane System that concentration is 0.015 ~ 0.25mol/l, after the high-speed stirring 15 ~ 20 minutes, put into the clean millipore filtration of surface treatment and soaked 20 ~ 48 hours, then film is taken out, with filter paper surperficial oil phase is wiped clean, the reaction unit of packing into makes reaction unit be immobilized liquid membrane in the middle of forming, about be the isolated system of solution phase; Respectively there is an electric stirring instrument film both sides; Second step: the method elder generation compound concentration of control shape and appearance of calcium carbonate is 0.2 ~ 0.3mol/l sodium carbonate solution, with concentration be 0.5 ~ 0.6mol/l calcium chloride solution, place respectively the left and right sides of the immobilized liquid membrane of the above-mentioned the first step, stirring at low speed or add again the reaction of 1 ~ 2% additive stirring at low speed after 0.1 ~ 48 hour in sodium carbonate solution one side, get throw out in sodium carbonate solution one side centrifugal, clean and namely obtain cubic or spherical or shuttle shape or column or nano-sheet CaCO
3Product.
Document: [Ota Y, Inui S, Iwashita T, etal.Preparation of aragonite whiskers [J] .Journal of American Ceramic Society, 1995,78 (7): 1983-1984] are with Ca (OH)
2Join MgCl
2In the solution, obtain the pH value and be approximately 9 CaCl
2-MgCl
2-Mg (OH)
2Then suspension pass into CO with certain flow
2Gas carries out carbonation reaction and prepares calcium carbonate crystal whisker, and finally having obtained length-to-diameter ratio is that 20-80, diameter are the calcium carbonate crystal whisker of 0.5-1 μ m.The MgC1 that adds in the building-up process
2As crystal type promoting reagent.
Document: [Sun Hongjuan, Chang Youjun. Bubbling method prepares the experimental study [J] of Aragonite Style Calcium Carbonate Whiskers. Chinese Mining Industry, 2005,14 (2): 77-79.] in the aqueous solution, Ca (OH)
2Hydrolysis reaction occurs, and leads to CO in calcium hydroxide aqueous solution
2Gas is controlled the generation of standby calcium carbonate crystal whisker by the variation of surveying specific conductivity, and add crystal type promoting reagent (MgCl in the aqueous solution
2) can prepare calcium carbonate crystal whisker.They are with MgCl
2-Ca (OH)
2-CO
2Be reaction system, temperature of reaction is 90 ℃, and adds MgC1
2As crystal type promoting reagent, then pass into CO
2Gas makes system generation carbonation reaction.At MgCl
2Effect under, calcium carbonate is separated out with the aragonitic crystal, is about 0.5-1 μ m but the calcium carbonate crystal whisker length that they obtain is 15-20 μ m, diameter, length-to-diameter ratio only is that product is not ideal enough about 15-20.
At present, the domestic Han Zhihua of only having, Xie Yuanyan utilize sol-gel method to synthesize calcium carbonate crystal whisker, document: [Han Zhihua, Cao Lin .CaCO
3The preparation and characterization of nano wire [J]. Journal of Inorganic Materials, 2005,20 (6): 1349-1352.], [Xie Yuanyan, Yang Hailin etc. sol-gel method prepares calcium carbonate crystal whisker [J]. Materials Science and Engineering of Powder Metallurgy, 2009,14 (3): 165-168.].The whisker of sol-gel method production is bar-shaped, and length and diameter Distribution are more even, and length-to-diameter ratio is about 30, but has mutually bonding phenomenon, and dispersiveness has much room for improvement.
In addition, Shang Wenyu, Zhang Li, Xie Yinghui, Chen Xianyong, entirely learn military affairs, Wang Huili etc. also carried out the correlative study that carbonation method prepares calcium carbonate crystal whisker, obtains certain achievement in research.Concrete document has:
Document: Shang Wenyu, Liu Qingfeng, Chen Shoutian.Synthesis of aragonite whiskers using gas-liquid System[J] .Journal of Xi ' an Jiaotong University, 1999,33 (10): 10-13.
Document: Li Jiu, Chen Huaxiong.Calcium carbonate whiskers prepared with magnesium dichloride as crystalline controller [J] .Journal of the Chinese Ceramic Society, 2005,33 (9): 1153-1156.
Document: a Li, Zhang Zhao, Guo Hongdan, etc. the preparation of homogeneous preparation of aragonite whisker and Exploration of Mechanism [J]. Sichuan University's journal (engineering science version), 2002,34 (3): 46-49.
Document: Xie Yinghui, He Yuji, Wang Guiyun, etc. the study on the synthesis of calcium carbonate whisker [J]. chemical science and technology, 2000,8 (6): 13-14.
Document: Chen Xianyong, Tang Qin, Qu Zhonghua, etc. the preparation research of high length-diameter ratio calcium carbonate crystal whisker [J]. Henan chemical industry, 2005,22 (5): 16-18.
Document: Quan Xuejun, Sun Zhifu.Preparation and filling performance of calcium carbonate whiskers [J] .Journal of Wuhan University of Technology, 2003,25 (8): 8-11.
Document: Wang Huili, Zhao Lihua, Liu Bin, etc. carbonation reaction carbonate synthesis calcium pyroborate research [J] in the simulation carbonating tower. nonmetalliferous ore, 2003,26 (6): 17-18.
Document: John L Wray, Farrington Daniels.Precipitation of calcite and aragonite [J] .Journal of the American Chemistry Society, 1957,79 (7): 2031.
Document: Hu Zeshan, Deng Yulin.Synthesis of needle-like aragonite from calcium chloride and sparingly soluble magnesium carbonate[J] .Powder Technology, 2004,140 (1-2): 10.
Document: Zhang Xiuying, Liao Zhaojiang etc. the interaction of beta-cyclodextrin and calcium carbonate crystal [J]. chemical journal, 2003,61 (1): 69-73.
Document: Yoshiyuki K, Akiko S, Tamotsu Y, et al.Control of crystal shape and modification of calcium carbonate prepared by precipitation from calcium hydrogen carbonate solution[J] .Journal of the Ceramic Society of Japan, 1992,100 (9): 1145.
Document: Yan Changling, Lu Yan, Zhou Jianguo, etc. high purity high length-diameter ratio CaCO
3The preparation of whisker [J]. applied chemistry, 2004,21 (5): 515-517.
Document: Laifeng Wang, Ivan Sondi.Egon Matijevie.Preparation of Uniform Needle-like Aragonite Particles by Homogeneous Precipitation[J] .Journal of Colloid and Interface Science.1999,218:545-553.
Document: Xu Jing, Chen Qinghua, Qian Qingrong. Preparation of Aragonite Whiskers with Urea Hydrolytic Method [J]. structural chemistry, 2003,22 (2): 23.
Document: Fairchild G H, Henry George, Thatcher R I, et al.Acicular calcite and aragonite calcium carbonate:US Patent:6071336 [P] .2000,06,06.
Document about the calcium carbonate crystal whisker modification:
Document: [Li. the preparation of homogeneous aragonite phase calcium carbonate crystal whisker and growth mechanism research [D]. Chengdu: Sichuan University, 2002.]
The Zhang Li of Sichuan University adopts the surface modifying method of common light calcium carbonate and water-ground limestone, by suspension method in the water and the moisture content test, has studied the modified effect of calcium carbonate crystal whisker in stearic acid system and titanic acid ester system.Test-results shows: the two all can carry out modification to calcium carbonate crystal whisker effectively, and the consumption of titanate coupling agent is less than stearic acid when reaching complete modification, and the consumption of sodium stearate and titanate coupling agent approximately is about 1.5% of whisker weight; In the situation of same amount, titanate coupling agent will be got well the surface modification effect of whisker.
Document: [Li Lixia. one step carbonization preparation and the applied research [D] of calcium carbonate crystal whisker. Shenyang: Northeastern University, 2008.]
Northeastern University's Li Li casket has adopted several properties-correcting agent (stearic acid, sodium stearate, zinc octadecanate, Sodium dodecylbenzene sulfonate, sodium lauryl sulphate, titanic acid ester, Aluminate, silane, polyacrylamide) that calcium carbonate crystal whisker is carried out surface modification, several factors (consumption of properties-correcting agent, initial pulp density, modification temperature, modification time, stirring velocity, bake out temperature) have been investigated to the impact of calcium carbonate crystal whisker modified effect, by test activation index, the contact angle evaluation index as modified effect, obtain best modified condition.
Other relevant achievement documents have:
Document: Chen Yepu, Ji Hongnian, Zhao Yinggang etc. the surface modification of pearl filler [J]. Wuxi Light Industry Univ.'s journal, 1999,18 (4): 11-15.
Document: Chen Yepu etc., the Research on Surface Modification [J] of the industrial application of tensio-active agent ()-calcium carbonate. Surfactant Industry, 1997 (4): 28-31.
Document: Pan Helin, Xu Zhizhen. the research of calcium carbonate process of surface treatment and Exploration of Mechanism [J]. inorganic chemicals industry, 1997,4:13-14.
Document: accepting a heavy burden is far away, Yu Demei. the applied research [J] of aluminate coupling agent in calcium carbonate-filled ABS and PVC. and XI AN JIAOTONG UNIVERSITY Subject Index, 1994,28 (8): 104-108.
Document: Liang Shaojun, Huang Jinli, Liu Mingdeng. the research [J] of titanic acid ester surface treatment calcium carbonate. inorganic chemicals industry, 1997,5:31-32.
Document: Liu Lihua, Liu Huiyuan, Liu Donglian. aluminate coupling agent modified nano calcium carbonate effect research [J]. chemical industry mineral and processing, 2005,3:4-6.
Document: Zou Haikui, Chen Jianfeng, Liu Runjing, Shen Zhigang. nanometer CaCO
3Preparation, surface modification and sign [J]. Chinese powder technology, 2001,7 (5): 15-19.
Document: Jianfeng Chen, Taobo He, WeiWu.Adsorption of sodium salt of poly (acrylic) acid (PAANa) on nano-sized CaCO
3And dispersion of nano-sized CaCO
3In water [J]. Colloids and Surfaces, 2004,232:163-168.
Document: Zhang H, Chen J F, Zhou H K, Wang G Q, Yun J.Preparation of nano-sized precipitated calcium carbonate for PVC plastisol rheology modification[J]. Journal of Materials Science Letters, 2002,16.
Summary of the invention
The invention provides the synthetic and modification integral method of a kind of calcium carbonate crystal whisker based on sol-gel method, deepened the process of sol-gel method carbonate synthesis calcium pyroborate, and for calcium carbonate crystal whisker easily reunite and in cement-based material the problem of dispersed bad and bad adhesion, solution is proposed.
Whole reaction system is by aqueous solvent, acetic acid, citric acid, CaCO
3Form.CaCO
3Be dissolved in acetic acid solution, the solubilizing reaction shown in the following formula (1) occurs, emit CO
2
CH
3-COOH+CaCO
3→(CH
3-COO)
2Ca+H
2O+CO
2↑ (1)
Initial reaction stage, the solution pH value significantly raises.Add citric acid behind the 2h because the hydrolysis, the solution pH value reduces suddenly, along with the prolongation in reaction times, the acetate moiety in the solution (COOH) with solution in Ca
2+With hydroxyl in the citric acid (OH) combination, and reach gradually balance makes the pH value rising, reach a certain value after (PH ≈ 3.5) tend towards stability.React as follows:
-COOH+Ca
2+→-(COO)
2-Ca+2H
+ (2)
-COOH+-OH→-COOO+H
2O (3)
In water, citric acid and citrate of lime all are to be linear structure, wherein, and Ca
2+Can be combined with-COOH and form the citric acid inner complex of calcic, and this inner complex also is linear structure.This moment, solution became the oyster white colloid, and wherein colloidal particle is exactly linear calcic intermediate.Citric acid plays conclusive effect to the formation of the calcic intermediate of linearity.
The present invention is based on the synthetic and modification integral method of calcium carbonate crystal whisker of sol-gel method, concrete steps are as follows:
(1) adopts sol-gel method carbonate synthesis calcium pyroborate: at water, acetic acid, CaCO
3Add citric acid in the sol system that forms, heat in the water bath with thermostatic control, Heating temperature is 70 ± 2 ℃, and stirring velocity is 250r/min, and lasting stirring is no less than 12 hours, until modification finishes; Citric acid is as the Ca in the sequestrant binding soln
2+
When (2) above-mentioned calcium carbonate crystal whisker is synthetic, adds surface-modifying agent calcium carbonate crystal whisker is carried out modification, surface-modifying agent has chemical bonding or adsorption on the whisker surface, and has introduced hydrophobic grouping.With calcium carbonate crystal whisker filtration, washing, drying, be able to the calcic intermediate after the modification; Then the calcic intermediate is calcined being not less than under 500 ℃ of high temperature, time 90-120min obtains calcium carbonate crystal whisker.
Compared with prior art, the invention has the beneficial effects as follows:
(1) adopt natural limestone as raw material, wide material sources, cheap, be applicable to scale operation.
(2) adopting sol-gel method is basic synthetic method, has higher advance.
(3) modification and integrator are finished, production technique is simple, does not need specific equipment, can realize industrialization production.
(4) the calcium carbonate crystal whisker purity of the present invention's preparation is high, crystal formation is good, length-to-diameter ratio is large, have preferably quality, and good dispersity, strong with bond matrix power can significantly improve substrate performance in cement-based material.
Description of drawings
Fig. 1 is process flow sheet of the present invention.
Fig. 2 is scanning electron microscope (SEM) test result of embodiment product.
Fig. 3 is X-ray diffraction (XRD) test result of embodiment product.
Embodiment
Combination technology scheme and accompanying drawing are described in detail embodiments of the invention.
Embodiment:
With 2gCaCO
3Powder dissolution is in the acetic acid solution of 100ml in (0.5mol/L), behind 70 ℃ of heating of constant temperature water bath and the mechanical stirring 2h, in the settled solution of above-mentioned gained, add the 4g citric acid, continue constant temperature mechanical stirring 10h, settled solution becomes oyster white milk shape colloid gradually in the whipping process, add stearic acid properties-correcting agent, continue to stir 2h, stirring velocity is 250r/min.Then filtration, distilled water, absolute ethanol washing place 70 ℃ baking oven to dry for several times, obtain intermediate.Decompose under 550 ℃ of temperature in High Temperature Furnaces Heating Apparatus, thermal decomposition time is 100min, obtains calcium carbonate crystal whisker.
Accompanying drawing 3 is for making scanning electron microscope (SEM) picture of calcium carbonate crystal whisker, and product morphology analysis result: its length is about 20-30 μ m, and diameter is about 1 μ m, is needle bar shape.
Accompanying drawing 2 is X-ray diffraction (XRD) test results of embodiment product.Use XRD-6000 type X-ray diffractometer to carry out the crystal formation test, its main crystal formation is aragonite phase (a=0.4962nm, b=0.7968nm, c=0.5743nm), and calcium carbonate crystal whisker purity and degree of crystallinity are higher.
Comparative Examples:
Following table 1 is to use calcium carbonate crystal whisker that method of the present invention obtains and common calcium carbonate crystal whisker to be incorporated into cement paste, its each length of time folding strength, ultimate compression strength and crimping ratio the contrast form.Embodiment product and common whisker are mixed in the cement paste by 3% mass ratio respectively, measure folding strength in each, ultimate compression strength in the length of time, calculate the crimping ratio.The result shows: it is more remarkable that modified crystal whiskers improves the folding strength of cement paste, and toughening effect significantly improves, and with respect to the ordinary calcium carbonate whisker, 28d crimping ratio has improved 21%.
Table 1 is the toughening effect contrast of embodiment product and common whisker refinforced cement sill.
Claims (1)
1. the calcium carbonate crystal whisker based on sol-gel method synthesizes and the modification integral method, and its feature may further comprise the steps:
(1) adopts sol-gel method carbonate synthesis calcium pyroborate: at water, acetic acid, CaCO
3Add citric acid in the sol system that forms, heat in the water bath with thermostatic control, Heating temperature is 70 ℃ ± 2 ℃, and stirring velocity is 250r/min, and lasting stirring is no less than 12 hours, until modification finishes;
(2) when step (1) calcium carbonate crystal whisker is synthetic, adds surface-modifying agent calcium carbonate crystal whisker is carried out modification; With calcium carbonate crystal whisker filtration, washing, drying, be able to the calcic intermediate after the modification; Then the calcic intermediate is calcined being not less than under 500 ℃ of high temperature, time 90-120min obtains calcium carbonate crystal whisker.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111908820A (en) * | 2020-08-14 | 2020-11-10 | 厦门大学 | Method for improving strength and toughness of concrete by using micro-nano material containing sulfonated fibers |
| CN113913968A (en) * | 2021-10-15 | 2022-01-11 | 四川省中科乐美新材料有限公司 | Preparation method of calcium carbonate fiber for improving performance of cement-based composite material |
| CN115304091A (en) * | 2022-07-12 | 2022-11-08 | 西安建筑科技大学 | Preparation method of aragonite phase calcium carbonate |
-
2012
- 2012-11-27 CN CN2012104907502A patent/CN102943306A/en active Pending
Non-Patent Citations (2)
| Title |
|---|
| 李丽匣,等: "碳酸钙晶须的表面改性", 《IM&P化工矿物与加工》 * |
| 谢元彦,等: "溶胶凝胶法制备碳酸钙晶须", 《粉末冶金材料科学与工程》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111908820A (en) * | 2020-08-14 | 2020-11-10 | 厦门大学 | Method for improving strength and toughness of concrete by using micro-nano material containing sulfonated fibers |
| CN111908820B (en) * | 2020-08-14 | 2022-01-04 | 厦门大学 | Method for improving strength and toughness of concrete by using micro-nano material containing sulfonated fibers |
| CN113913968A (en) * | 2021-10-15 | 2022-01-11 | 四川省中科乐美新材料有限公司 | Preparation method of calcium carbonate fiber for improving performance of cement-based composite material |
| CN115304091A (en) * | 2022-07-12 | 2022-11-08 | 西安建筑科技大学 | Preparation method of aragonite phase calcium carbonate |
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