CN1141272C - Methd of composing ceramic powder with liquid gel - Google Patents
Methd of composing ceramic powder with liquid gel Download PDFInfo
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- CN1141272C CN1141272C CNB011041455A CN01104145A CN1141272C CN 1141272 C CN1141272 C CN 1141272C CN B011041455 A CNB011041455 A CN B011041455A CN 01104145 A CN01104145 A CN 01104145A CN 1141272 C CN1141272 C CN 1141272C
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Abstract
The present invention belongs to the technical field ceramic materials, which relates to an improvement of a process for preparing ceramic powder. The process for preparing ceramic powder comprises: a water-soluble organic monomer, a water-soluble crosslinking agent and raw materials of the powder to be prepared are mixed, added with water, and mixed in a ball milling mode so as to form slurry; the slurry is gelated under the action of an initiator in the redox system at room temperature, and wet gelatin block is dried and calcinated at high temperature so as to obtain the desired ceramic powder. The present invention has the advantages of simple technique, low cost, easy operation, wide application range and small environmental pollution; the obtained powder is high in quality; therefore, the present invention is suitable for industrial production.
Description
The invention belongs to technical field of ceramic material, relate to ceramic powder preparation technology's improvement.
The characteristic of ceramic powder has material impact to the preparation technology and the microtexture of special ceramic material, and the performance to ceramic component produces considerable influence then.Therefore, research prepares the importance that high performance ceramic powder is the stupalith development always with advanced processing method.At present traditional ceramic powder preparation method has solid phase method, liquid phase method, vapor phase process, mechanical process and solvent evaporated method etc., adopts these traditional methods to prepare ceramic powder and has usually that the purity of powder composition inequality, synthesis temperature height, complex procedures, equipment requirements height and powder is not high, granularity is difficult to reach problems such as requirement.The A.Douy of France in 1989 and P.Odier have proposed a kind of way (Mat.Res.Bull. with polyacrylamide liquid phase gel method synthesize ceramic oxide powder, Vol.24, pp.1119～1126,1989, Printed in the USA, Pergamon Press plc.), but this method can only adopt water-soluble salt as raw material, cost is higher, and certain environmental pollution is arranged, and makes its range of application be subjected to certain limitation.The old afterwards big bright method that waits the people to propose a kind of new synthesize ceramic composite granule---gel solid reaction process (Chinese patent application number: 99100590.2).This method adopts water-soluble organic monomer and linking agent be added to and mixes in the aqueous solution that contains the required raw material of preparation ceramic powder or the water slip that (these raw materials both can be water miscible, also can be non-water-soluble), make monomer and linking agent gel at certain condition again, the raw material and the water solvent that mix are strapped in the high molecular three-dimensional network dehydration then, dry, calcining synthesizing ceramic powder.
Before go a step further again on the basis of the technology of solution gel powder process though the gel solid reaction process prepares the method for ceramic powder, but still have some problems.At first, gel mode in its technology is heating gel or catalyzer gel, if adopt the mode gel of heating, then need slurry is heated to 60～90 ℃ high temperature, cause process complications, the production cycle prolongs, and has increased energy consumption and equipment cost, and heating may cause that some raw material has just decomposed before gel, the quality of the final powder that obtains of influence.For catalyzer gel mode, find in the research if with in the disposable adding slip after initiator and the catalyst mix, then initiator can be followed blended catalyst reaction with it, makes initiator can't produce enough free radical trigger monomer polymerizations, thereby can't realize the gelation of slip.Must add in the slip respectively both in two steps like this, because catalyzer is bigger to the influence of gel speed, aforesaid operations makes complex technical process and gel speed restive, and slip is prone to caking phenomenon, gel is inhomogeneous, causes the quality of the last powder that obtains inhomogeneous.On the other hand, the price of the catalyzer Tetramethyl Ethylene Diamine that adopts in the above-mentioned technology is higher, can improve production cost undoubtedly in scale operation.Simultaneously Tetramethyl Ethylene Diamine has strong impulse smell and inflammable, belongs to hazardous substance (danger rule number: 32178), therefore production environment is had certain pollution and harm.In addition, prepare in the technology of ceramic powder in the gel solid state reaction, because organic content very little, only contain the organic monomer that is no more than raw material weight 10wt%, the space that produces behind the binder removal is limited, can not be effectively that raw material powder is separated, and therefore calcining back powder has often formed firm block, be difficult to fragmentation, be difficult to obtain the loose powder of desirable particle size.
The objective of the invention is, propose a kind of gel powder process novel process, make the water slip of raw material can be at room temperature carry out gel with simpler and more direct, cheap and safe mode, and characteristics such as the ceramic powder of gained is more loose, even, tiny after calcining.
Technical scheme of the present invention is, a kind of method of liquid organic polymer preparing gel powder is characterized in that, this method is made up of following steps:
(1) raw material that desire is prepared ceramic powder in accordance with regulations proportioning join in the ball grinder, ratio of grinding media to material is 1: 1～5: 1, in ball grinder, add entry, organic monomer and linking agent, amount of water is 50～200% of a raw material weight, monomer is third rare acid amides, vinylformic acid, the rare acid amides of methyl-prop, a kind of in the methacrylic acid, linking agent is a kind of in methylene-bis third rare acid amides or the polyethylene glycol dimethacrylate, total add-on of organic monomer and linking agent is 1～50% of a raw material weight, the weight ratio of organic monomer and linking agent is 3: 1～30: 1, also add sucrose or water soluble starch in ball grinder, add-on is 10～100% of a raw material weight.With above material ball milling in ball grinder, form the water slip, the ball milling time is 1～100 hour.
(2) above-mentioned ball milling is good water slip places container, add the redox system initiator, add-on is 0.1～1% of an organic monomer weight, stir, used oxygenant is an ammonium persulphate in the redox system initiator, Potassium Persulphate, the combination of one or more materials in Sodium Persulfate and the hydrogen peroxide, reductive agent is an ammonium sulphite, S-WAT, potassium sulfite, the combination of one or more materials in sodium bisulfite and the Sulfothiorine, earlier they are mixed with mixed aqueous solution before using, the total mass of reductive agent and oxygenant be water quality 2～20%, wherein the ratio of reductive agent and oxygenant add-on is 1: 5～5: 1.
(3) the above-mentioned slip that stirs is left standstill under the room temperature in container above 15 minutes, wait for slurry gel.
(4) the wet gel piece is taken out drying and dehydrating in natural air drying or the baking oven about 60 ℃ in container.
(5) dried gel piece is placed calcining furnace be heated to the synthesis temperature of regulation, the insulation certain hour promptly gets required ceramic powder.
Compare with the synthetic flouring technology of gel in the past, this technology has many advantages.At first, use present method both can prepare the ceramic powder of single component, can prepare ceramic composite powder again, raw materials used both can be water-soluble, also can be water-insoluble, so applicable surface was very wide.Secondly, the mixed raw materials slip can at room temperature carry out when gel naturally, need not heating, do not need to add initiator and catalyzer in two steps respectively yet, can cause slurry gel fast, uniformly, save the energy and only need a step to add the redox system initiator, need not specific equipment, operation is simpler, and cost is lower, does not also have environmental pollution.In addition, in gel flouring technology in the past, a spot of monomer shared space of formed macromolecule network in gelation process stops the contact of powder particulate and avoids the sintering alligatoring of powder in calcination process to be difficult to achieve the goal in the simple dependence slip, the powder of gained is prone to hard aggregation, the particle diameter inequality, often need the pulverizing of wasting time and energy, milled processed, and in this technology except the organic monomer and linking agent that are used for gel, also in slip, add a certain amount of sucrose or starch in addition, they play the effect of obstruct in slip, at high temperature their a large amount of spaces of staying after by burn off make that the powder of calcining back gained is fluffy, particle diameter is tiny evenly, very easily or need not to pulverize.And, the organism of adding more amount in slip, they can decompose under the high temperature non-oxygenated environment, the carbon of residual more amount, it is required to offer some reaction that needs carbon to participate in.Therefore, the present invention compares with gel flouring technology in the past, have widely applicable, cost is low, easy and simple to handle, environmental pollution is little, gained powder quality advantages of higher, is suitable for industrialized production.
Below the present invention is described in further details.Processing method of the present invention still adopts third rare acid amides to make monomer, make linking agent with methylene-bis third rare acid amides, they are added water with the required ceramic raw material of powder process mixes, again the disposable adding slip of a kind of redox system initiator is stirred, at room temperature cause slurry gel, gel piece promptly gets required ceramic powder after the certain temperature calcining.The principle of this method is to utilize some oxygenant and reductive agent at room temperature to react the generation free radical, and the activation energy that reacts required is very low, therefore can at room temperature produce a large amount of effective free radical trigger monomer and linking agent polymerization, reach and make slip or contain monomer and the purpose of the mixing solutions gel solidification of linking agent, regulate oxygenant and the ratio of reductive agent and always add-on can control the speed of monomer and linking agent gel speed.In addition, when configuration contains the slip of monomer and linking agent or mixing solutions, the organism that can add more amount, play the effect of separating ceramic raw material in the gel piece, a large amount of spaces that they are at high temperature stayed behind the burn off can make the ceramic powder of calcining out loose, avoid the appearance of hard aggregation or sintering phenomenon, powder is pulverized easily or be need not and pulverizes, and is dispersed and have good uniformity.
The liquid gel milling method of the present invention's design, form by following steps:
1, the raw material that desire is prepared ceramic powder proportioning in accordance with regulations joins in the ball grinder, ratio of grinding media to material is 1: 1～5: 1, in ball grinder, add entry, organic monomer and linking agent, amount of water is 50～200% of a raw material weight, monomer is third rare acid amides, vinylformic acid, the rare acid amides of methyl-prop, a kind of in the methacrylic acid, linking agent is a kind of in methylene-bis third rare acid amides or the polyethylene glycol dimethacrylate, total add-on of organic monomer and linking agent is 1～50% of a raw material weight, the weight ratio of organic monomer and linking agent is 3: 1～30: 1, also add sucrose or water soluble starch in ball grinder, add-on is 10～100% of a raw material weight.With above material ball milling in ball grinder, form the water slip, the ball milling time is 1～100 hour.
2, above-mentioned ball milling is good water slip places container, adds the redox system initiator, and add-on is 0.1～1% of an organic monomer weight, stirs.Used oxygenant is the combination of one or more materials in ammonium persulphate, Potassium Persulphate, Sodium Persulfate and the hydrogen peroxide in the redox system initiator, and reductive agent is the combination of one or more materials in ammonium sulphite, S-WAT, potassium sulfite, sodium bisulfite and the Sulfothiorine.Earlier they are mixed with mixed aqueous solution before using, the total mass of reductive agent and oxygenant be water quality 2～20%, wherein the ratio of reductive agent and oxygenant add-on is 1: 5～5: 1, and stoichiometric ratio be about 1: 1 more excellent, the ratio of the free radical that produce this moment is higher, can improve the efficient of gel.
3, the above-mentioned slip that stirs is left standstill under the room temperature in container, wait for slip nature gel.Gel time is relevant with the initiator add-on with the monomer add-on, and the add-on of monomer and initiator is many more, and required gel time is short more.
4, the wet gel piece is taken out drying and dehydrating in natural air drying or the baking oven about 60 ℃ in container.
5, dried gel piece is placed calcining furnace be heated to the synthesis temperature of regulation, the insulation certain hour promptly obtains required ceramic powder.The gained powder generally need not to pulverize, and grinds a little and gets final product sieving for standby
Embodiment 1: be equipped with the superfine zirconia powder with liquid gel powder process legal system.
With industrial ZrOCl
2Be raw material, purity 99.5% takes by weighing 1 kilogram, take by weighing organic monomer third rare acid amides 10 grams simultaneously, N, N-methylene-bis third rare acid amides 3 grams, sucrose 100 grams, taking by weighing thing more than inciting somebody to action pours in the ball grinder, in ball grinder, add 1 kilogram in water, 1 kilogram of abrading-ball, ball milling 1 hour on ball mill then, wherein institute's grind materials takes out, and it is standby to cross 100 mesh sieves.Get ammonium persulphate 10 gram, ammonium sulphite 10 grams, adding water after the mixing, to be made into concentration be 20% redox system initiator solution.Add 0.5ml redox system initiator in the raw material slip that has ground, stir, at room temperature left standstill then 30 minutes, slurry gel solidifies.The wet gel piece is taken out from container, place 60 ℃ of oven dry of baking oven, place retort furnace to be warming up to 800 ℃ then, be incubated after 2 hours and take out, promptly get high pure and ultra-fine ZrO
2Powder.
Embodiment 2: be equipped with the YAG powder with the liquid gel legal system.
With Al
2O
3, Y (NO
3)
3Be raw material, wherein Al: Y=5: 3, Al
2O
3Particle diameter be 2.6 μ m; The deionized water that adds raw material weight 50%, the ammonium polyacrylate that adds raw material weight 1% is simultaneously made dispersion agent to improve grinding efficiency; Add organic monomer methacrylic acid and linking agent polyethylene glycol dimethacrylate, adding total amount is 20% of raw material weight, and wherein monomer is 30: 1 with the ratio of the weight of linking agent, and above material is joined in the ball grinder, add starch simultaneously, add-on is 20% of a raw material weight.With above material ball milling 100 hours, it was standby to cross 100 mesh sieves after the discharging.Compound concentration is 2% redox system initiator solution, and wherein oxygenant is a Sodium Persulfate, and reductive agent is a Sulfothiorine, and oxygenant is 5: 1 with the ratio of reductive agent add-on.Add initiator in the raw material slip that ball milling is good, add-on is 0.1% of a monomer weight, and stirs, and at room temperature leaves standstill slurry gel 15 minutes.The wet gel piece is taken out in container, dry naturally under the room temperature, place retort furnace to be warmed up to 1200 ℃ of calcinings 2 hours then, obtain the loose powder of white.The gained powder is carried out the analysis of X diffraction structure, and the result proves that raw material all is converted into the YAG powder.
Embodiment 3: be equipped with the AlN powder with the liquid gel legal system.
With industrial Al
2O
3With Graphite Powder 99 be raw material, particle diameter is respectively 2 μ m and 10 μ m, is that 4: 1 ratio joins in the ball grinder by weight; Add Al
2O
3The organic monomer third rare acid amides and the linking agent N of weight 50%, N-methylene-bis third rare acid amides, monomer is 20: 1 with the ratio of linking agent weight; Add and Al
2O
3The sucrose that weight is identical adds and is equivalent to Al
2O
3The water of the amount that weight is 2 times and Al
2O
3The dispersion agent JA-281 of weight 1%.With above material ball milling 24 hours, it was standby to cross 100 mesh sieves after the discharging.Configuration concentration is 10% redox system initiator solution, and wherein oxygenant is Potassium Persulphate, Sodium Persulfate, and reductive agent is S-WAT, potassium sulfite, and the ratio of the add-on of four kinds of materials is 1: 1: 5: 5.The initiator for preparing is joined in the raw material slip that has ground, and add-on is 0.5% of a monomer mass, stirs, and leaves standstill under the room temperature then 20 minutes, treats behind the slurry gel wet gel piece to be taken out and be broken into 2～5cm in container
3Fritter, in air, dry naturally.The xerogel piece is put into carbon tube furnace, logical high pure nitrogen, slowly be warmed up to 600 ℃, make the organism in the gel piece resolve into the required carbon of reaction, and obtain a large amount of micropores be beneficial to react in the circulation of gas, be rapidly heated 1550 ℃ then, be incubated 4 hours, promptly obtain loose, high-purity AlN micro mist.
Embodiment 4: with the synthetic PZT powder of liquid gel method.
With chemical pure PbO, TiO
2And ZrO
2Be raw material, purity all is 99.8%, and by Pb: Zr: Ti=100: 53: 47 stoichiometric ratio takes by weighing raw material, adds in the ball grinder; In ball grinder, add the ZrO that is equivalent to 2 times of raw material dry powder weight
2Abrading-ball; Add the sucrose be equivalent to raw material dry powder weight 50% and with heavy distilled water such as raw material dry powder, add organic monomer acrylamide and linking agent N, N-methylene-bis third rare acid amides, adding total amount is 10% of raw material weight, wherein monomer is 30: 1 with the ratio of the weight of linking agent.With above material ball milling 48 hours, it was standby to cross 200 mesh sieves after the discharging.Configuration concentration is 5 redox system initiator solution, and wherein oxygenant is an ammonium persulphate, and reductive agent is an ammonium sulphite, and the ratio of the add-on of 2 kinds of materials is 2: 1.The initiator for preparing is joined in the raw material slip that has ground, add-on is 0.5% of a monomer mass, stir, left standstill under the room temperature then 30 minutes, treat behind the slurry gel wet gel piece to be taken out in container, place 60 ℃ of oven dry of baking oven, place retort furnace to be warming up to 800 ℃ then, be incubated after 2 hours and take out, promptly get loosely organized, composition homogeneous high purity PZT powder.
Claims (1)
1, a kind of method of liquid organic polymer preparing gel powder is characterized in that, this method is made up of following steps:
(1) raw material that desire is prepared ceramic powder in accordance with regulations proportioning join in the ball grinder, ratio of grinding media to material is 1: 1～5: 1, in ball grinder, add entry, organic monomer and linking agent, amount of water is 50～200% of a raw material weight, monomer is third rare acid amides, vinylformic acid, the rare acid amides of methyl-prop, a kind of in the methacrylic acid, linking agent is a kind of in methylene-bis third rare acid amides or the polyethylene glycol dimethacrylate, total add-on of organic monomer and linking agent is 1～50% of a raw material weight, the weight ratio of organic monomer and linking agent is 3: 1～30: 1, also add sucrose or water soluble starch in ball grinder, add-on is 10～100% of a raw material weight.With above material ball milling in ball grinder, form the water slip, the ball milling time is 1～100 hour;
(2) above-mentioned ball milling is good water slip places container, add the redox system initiator, add-on is 0.1～1% of an organic monomer weight, stir, used oxygenant is an ammonium persulphate in the redox system initiator, Potassium Persulphate, the combination of one or more materials in Sodium Persulfate and the hydrogen peroxide, reductive agent is an ammonium sulphite, S-WAT, potassium sulfite, the combination of one or more materials in sodium bisulfite and the Sulfothiorine, earlier they are mixed with mixed aqueous solution before using, the total mass of reductive agent and oxygenant be water quality 2～20%, wherein the ratio of reductive agent and oxygenant add-on is 1: 5～5: 1;
(3) the above-mentioned slip that stirs is left standstill under the room temperature in container, wait for slip nature gel;
(4) the wet gel piece is taken out drying and dehydrating in natural air drying or the baking oven about 60 ℃ in container;
(5) dried gel piece is placed calcining furnace be heated to the synthesis temperature of regulation, the insulation certain hour promptly gets required ceramic powder.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB011041455A CN1141272C (en) | 2001-02-22 | 2001-02-22 | Methd of composing ceramic powder with liquid gel |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB011041455A CN1141272C (en) | 2001-02-22 | 2001-02-22 | Methd of composing ceramic powder with liquid gel |
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| CN1370757A CN1370757A (en) | 2002-09-25 |
| CN1141272C true CN1141272C (en) | 2004-03-10 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103419268A (en) * | 2013-06-28 | 2013-12-04 | 无锡特科精细陶瓷有限公司 | Water-based gel casting method for structural ceramics |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101357847B (en) * | 2008-08-29 | 2013-03-13 | 中国科学院上海硅酸盐研究所 | Organic carbon source for pouring and molding silicon carbide aqueous gel and molding technique |
| CN105418071B (en) * | 2015-07-28 | 2018-01-16 | 山东合创明业精细陶瓷有限公司 | The synthetic method of high pure and ultra-fine ZrC SiC composite granules |
| CN111662083A (en) * | 2020-06-24 | 2020-09-15 | 红河学院 | Method for preparing LaSNYSZ composite ceramic by doping multiple rare earths |
| CN117534326B (en) * | 2023-12-12 | 2024-09-10 | 广东兴辉陶瓷集团有限公司 | Preparation method of rock plate protection glaze and printed rock plate |
-
2001
- 2001-02-22 CN CNB011041455A patent/CN1141272C/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103419268A (en) * | 2013-06-28 | 2013-12-04 | 无锡特科精细陶瓷有限公司 | Water-based gel casting method for structural ceramics |
| CN103419268B (en) * | 2013-06-28 | 2016-03-23 | 无锡特科精细陶瓷有限公司 | A kind of structural ceramics water-base gel casting method |
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| CN1370757A (en) | 2002-09-25 |
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