CN116372181B - Rod-shaped silver powder and preparation method thereof - Google Patents
Rod-shaped silver powder and preparation method thereof Download PDFInfo
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- CN116372181B CN116372181B CN202310666079.0A CN202310666079A CN116372181B CN 116372181 B CN116372181 B CN 116372181B CN 202310666079 A CN202310666079 A CN 202310666079A CN 116372181 B CN116372181 B CN 116372181B
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- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 title claims abstract description 131
- 238000002360 preparation method Methods 0.000 title claims abstract description 17
- 229910052709 silver Inorganic materials 0.000 claims abstract description 25
- 239000004332 silver Substances 0.000 claims abstract description 25
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 46
- 239000000243 solution Substances 0.000 claims description 42
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 36
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 claims description 32
- 238000003756 stirring Methods 0.000 claims description 20
- 238000001914 filtration Methods 0.000 claims description 16
- 229910001961 silver nitrate Inorganic materials 0.000 claims description 16
- 229920000036 polyvinylpyrrolidone Polymers 0.000 claims description 15
- 239000001267 polyvinylpyrrolidone Substances 0.000 claims description 15
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 claims description 15
- 238000002156 mixing Methods 0.000 claims description 11
- 239000008367 deionised water Substances 0.000 claims description 9
- 229910021641 deionized water Inorganic materials 0.000 claims description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 9
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 8
- 239000004372 Polyvinyl alcohol Substances 0.000 claims description 8
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 8
- 229920002451 polyvinyl alcohol Polymers 0.000 claims description 8
- HSBFHUOJEGKWRL-KVVVOXFISA-N ethanol;(z)-octadec-9-enoic acid Chemical compound CCO.CCCCCCCC\C=C/CCCCCCCC(O)=O HSBFHUOJEGKWRL-KVVVOXFISA-N 0.000 claims description 7
- 238000005406 washing Methods 0.000 claims description 7
- 239000007864 aqueous solution Substances 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 5
- KYIDJMYDIPHNJS-UHFFFAOYSA-N ethanol;octadecanoic acid Chemical compound CCO.CCCCCCCCCCCCCCCCCC(O)=O KYIDJMYDIPHNJS-UHFFFAOYSA-N 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- WRIDQFICGBMAFQ-UHFFFAOYSA-N (E)-8-Octadecenoic acid Natural products CCCCCCCCCC=CCCCCCCC(O)=O WRIDQFICGBMAFQ-UHFFFAOYSA-N 0.000 claims description 3
- LQJBNNIYVWPHFW-UHFFFAOYSA-N 20:1omega9c fatty acid Natural products CCCCCCCCCCC=CCCCCCCCC(O)=O LQJBNNIYVWPHFW-UHFFFAOYSA-N 0.000 claims description 3
- QSBYPNXLFMSGKH-UHFFFAOYSA-N 9-Heptadecensaeure Natural products CCCCCCCC=CCCCCCCCC(O)=O QSBYPNXLFMSGKH-UHFFFAOYSA-N 0.000 claims description 3
- ZQPPMHVWECSIRJ-UHFFFAOYSA-N Oleic acid Natural products CCCCCCCCC=CCCCCCCCC(O)=O ZQPPMHVWECSIRJ-UHFFFAOYSA-N 0.000 claims description 3
- 239000005642 Oleic acid Substances 0.000 claims description 3
- QXJSBBXBKPUZAA-UHFFFAOYSA-N isooleic acid Natural products CCCCCCCC=CCCCCCCCCC(O)=O QXJSBBXBKPUZAA-UHFFFAOYSA-N 0.000 claims description 3
- ZQPPMHVWECSIRJ-KTKRTIGZSA-N oleic acid Chemical compound CCCCCCCC\C=C/CCCCCCCC(O)=O ZQPPMHVWECSIRJ-KTKRTIGZSA-N 0.000 claims description 3
- 230000007935 neutral effect Effects 0.000 claims 1
- 239000002131 composite material Substances 0.000 abstract description 12
- 229920000049 Carbon (fiber) Polymers 0.000 abstract description 8
- 239000004917 carbon fiber Substances 0.000 abstract description 8
- 239000000853 adhesive Substances 0.000 abstract description 3
- 230000001070 adhesive effect Effects 0.000 abstract description 3
- 238000000576 coating method Methods 0.000 abstract description 3
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 abstract description 3
- 239000000843 powder Substances 0.000 abstract description 3
- 229910052751 metal Inorganic materials 0.000 abstract description 2
- 239000002184 metal Substances 0.000 abstract description 2
- 230000000052 comparative effect Effects 0.000 description 16
- 238000000034 method Methods 0.000 description 10
- 230000006872 improvement Effects 0.000 description 8
- 239000003638 chemical reducing agent Substances 0.000 description 7
- 238000006243 chemical reaction Methods 0.000 description 6
- 239000002245 particle Substances 0.000 description 6
- 239000011159 matrix material Substances 0.000 description 5
- 230000008569 process Effects 0.000 description 5
- 239000011231 conductive filler Substances 0.000 description 4
- 239000011347 resin Substances 0.000 description 4
- 229920005989 resin Polymers 0.000 description 4
- FOIXSVOLVBLSDH-UHFFFAOYSA-N Silver ion Chemical compound [Ag+] FOIXSVOLVBLSDH-UHFFFAOYSA-N 0.000 description 3
- 229920000642 polymer Polymers 0.000 description 3
- 238000006479 redox reaction Methods 0.000 description 3
- -1 silver ions Chemical class 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 235000021355 Stearic acid Nutrition 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000013007 heat curing Methods 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000004005 microsphere Substances 0.000 description 2
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 2
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 239000008117 stearic acid Substances 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- JBTWLSYIZRCDFO-UHFFFAOYSA-N ethyl methyl carbonate Chemical compound CCOC(=O)OC JBTWLSYIZRCDFO-UHFFFAOYSA-N 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000010907 mechanical stirring Methods 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000006722 reduction reaction Methods 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/07—Metallic powder characterised by particles having a nanoscale microstructure
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
Abstract
The invention discloses a rod-shaped silver powder and a preparation method thereof, and relates to the technical field of metal powder preparation. According to the invention, the silver ammine complex ion is reduced by formaldehyde, the rod-shaped silver powder which is in a more regular cylindrical shape and has the length of 10-50 mu m and the diameter of 1.5-5 mu m is prepared, the structure of the silver powder is highly similar to that of carbon fibers, and the silver powder can be used for replacing carbon fibers in composite materials with high requirements on electric conduction and heat conduction properties and can also be used in conductive adhesives and electromagnetic shielding coatings.
Description
Technical Field
The invention relates to the technical field of metal powder preparation, in particular to rod-shaped silver powder and a preparation method thereof.
Background
The conductive composite material is generally prepared by adding a polymer or filler with conductive performance into a matrix polymer by physical or chemical means, so that the composite material has the mechanical and thermal properties of the matrix polymer on one hand and has considerable conductive performance on the other hand. The performance of the conductive composite is largely dependent on the formation of a conductive network of conductive filler in the matrix resin, which is not only related to the dispersion of the conductive filler in the matrix resin, but also to the effective bridging of the conductive filler in the matrix resin.
Silver powder is widely used in various conductive materials due to its unique conductivity and oxidation resistance. According to different application scenes, the silver powder particles have different requirements on morphology and size. As a conductive material, the flaky silver powder particles and the rod-shaped silver powder particles are easier to contact and form a three-dimensional net-shaped conductive loop, so that the resistance is relatively low and the conductive performance is more excellent. Therefore, the silver powder in the form of a plate or rod is often selected for the conductive composite material. Meanwhile, the three-dimensional net structure formed by overlapping the rod-shaped silver powder in the material can also play a role in improving the mechanical property of the composite material.
In the prior art, the patent with the publication number of CN 105921765B discloses a preparation method of rod-shaped silver powder with controllable particle size, which comprises the steps of dispersing spherical nano silver powder in an ester solvent, magnetically stirring at room temperature, centrifuging the obtained mixed solution, standing, cleaning sediment by deionized water and ethanol, and drying to obtain the rod-shaped silver powder with the length of 600-2000 nm. The rod-shaped silver powder prepared by the scheme is regular in shape and uniform in granularity, but smaller in size, and cannot meet the requirement of the composite material on large-size silver powder.
In view of the above, there is a need to design a rod-shaped silver powder and a method for preparing the same to solve the above problems.
Disclosure of Invention
The invention aims to provide the rod-shaped silver powder which can effectively reduce the treatment cost of raw materials and wastewater, is simple in preparation process, has larger particle size, and is suitable for preparing composite materials with higher requirements on electric conduction and heat conduction properties, and the preparation method thereof.
In order to achieve the above object, the present invention provides a method for preparing a rod-like silver powder, comprising the steps of:
s1, adding a predetermined amount of silver nitrate into deionized water, uniformly mixing, adding a certain amount of polyvinylpyrrolidone, uniformly mixing, and then dropwise adding ammonia water until the solution is clear; adding a certain amount of sodium hydroxide, fully mixing, and then continuously dropwise adding ammonia water until the solution is clarified to obtain a silver solution;
s2, adding a predetermined amount of formalin into the silver solution prepared in the step S1 under the condition of constant temperature stirring at 0-25 ℃; adding a certain amount of stearic acid-ethanol solution, stirring, filtering and washing to obtain first silver powder;
and S3, filtering the first silver powder prepared in the step S2, dispersing the first silver powder in a polyvinyl alcohol aqueous solution, stirring and filtering the first silver powder, dispersing the first silver powder in an oleic acid-ethanol solution, stirring the first silver powder for a certain time, filtering the first silver powder, and drying the first silver powder to obtain the rod-shaped silver powder.
As a further improvement of the present invention, in step S1, the mass ratio of the silver nitrate to the polyvinylpyrrolidone is (5-6): (0.2-0.3).
As a further improvement of the present invention, in step S1, the mass ratio of the silver nitrate to the sodium hydroxide is (5-6): (0-0.05).
As a further improvement of the present invention, the mass ratio of the silver nitrate to the formalin is (5-6): (10-15).
As a further improvement of the present invention, in step S2, the manner in which the formalin is added to the silver solution includes one-time pouring and slow dropping.
As a further improvement of the invention, the slow dropping rate is 10-100mL/min.
As a further improvement of the invention, in the step S3, the stirring time is 10-15min.
As a further improvement of the present invention, in step S3, the mass concentration of the aqueous polyvinyl alcohol solution is 1%, and the mass concentration of oleic acid in the oleic acid-ethanol solution is 0.5%.
As a further improvement of the present invention, in step S2, the washing operation is to wash the silver powder surface pH to neutrality using deionized water.
The invention also provides the rod-shaped silver powder, which is prepared according to the preparation method of the rod-shaped silver powder, wherein the length of the rod-shaped silver powder is 10-50 mu m, and the diameter of the rod-shaped silver powder is 1.5-5 mu m.
The beneficial effects of the invention are as follows:
according to the invention, formalin is used as a reducing agent, and the proportion of silver nitrate, PVP and formalin is controlled within a certain range, and the pH value of a reaction system is strictly controlled, so that the morphology and the size of silver powder are controlled through the regulation and control of the oxidation-reduction reaction rate, and the rod-shaped silver powder with a regular structure and higher conductivity is obtained.
The invention adopts the mode that formalin is added into silver solution, and controls the reduction speed of silver ions by controlling the addition speed, thereby controlling the growth morphology of silver powder; the reducing agent adopts a one-time pouring adding mode, rod-shaped silver powder and microsphere mixed silver powder can be prepared, and silver nano particles can play a role in welding the rod-shaped silver powder in a heat curing process, so that better conductivity can be obtained; the reducing agent is slowly dripped, and silver powder with similar structure to carbon fiber, better mechanical strength and regular rod-shaped structure can be prepared and applied to composite materials with certain requirements on conductivity and mechanical properties.
According to the invention, the silver ammine complex ion is reduced by formaldehyde, the rod-shaped silver powder which is in a more regular cylindrical shape and has the length of 10-50 mu m and the diameter of 1.5-5 mu m is prepared, the structure of the silver powder is highly similar to that of carbon fibers, and the silver powder can be used for replacing carbon fibers in composite materials with high requirements on electric conduction and heat conduction properties and can also be used in conductive adhesives and electromagnetic shielding coatings.
Drawings
FIG. 1 is a scanning electron microscope result of the rod-like silver powder of example 1.
FIG. 2 is a scanning electron microscope result of the rod-like silver powder of example 2.
FIG. 3 is a scanning electron microscope result of the rod-like silver powder of example 3.
FIG. 4 is a scanning electron microscope result of the rod-like silver powder of example 4.
FIG. 5 is a scanning electron microscope result of the silver powder of comparative example 1.
FIG. 6 is a scanning electron microscope result of the silver powder of comparative example 5.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.
It should be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and/or processing steps closely related to aspects of the present invention are shown in the drawings, and other details not greatly related to the present invention are omitted.
In addition, it should be further noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
The invention provides a preparation method of rod-shaped silver powder, which comprises the following steps:
s1, adding a predetermined amount of silver nitrate into deionized water, fully mixing, adding a certain amount of polyvinylpyrrolidone (PVP), uniformly mixing, and then dropwise adding ammonia water until the solution is clear; adding a certain amount of sodium hydroxide, fully mixing, and then continuously dropwise adding ammonia water until the solution is clarified to obtain a silver solution;
s2, adding a predetermined amount of formalin into the silver solution prepared in the step S1 under the condition of constant temperature stirring at 0-25 ℃; adding stearic acid-ethanol solution after 1min, stirring, filtering and washing to obtain first silver powder;
and S3, filtering the first silver powder prepared in the step S2, dispersing the first silver powder in a polyvinyl alcohol aqueous solution, stirring and filtering the first silver powder, dispersing the first silver powder in an oleic acid-ethanol solution, stirring the first silver powder for a certain time, filtering the second silver powder, and drying the second silver powder to obtain the rod-shaped silver powder.
Specifically, in step S1, the mass ratio of silver nitrate to polyvinylpyrrolidone is (5-6): (0.2-0.3), the mass ratio of the silver nitrate to the sodium hydroxide is (5-6): (0-0.05); the PVP model is K30; preferably, the amount of sodium hydroxide is 0-0.0.05g in 100mL deionized water; preferably, the mass ratio of silver nitrate to sodium hydroxide is (5-6): (0-0.03).
Specifically, the mass ratio of silver nitrate to formalin is (5-6): (10-15).
Specifically, in step S2, the mode of adding formalin into the silver solution comprises one-time pouring and slow dripping, wherein the slow dripping speed is 10-100mL/min; preferably, the formalin is added to the silver solution in a slow drop wise manner.
Specifically, in the step S2, the washing operation is to wash the surface pH of the silver powder to neutrality using deionized water; the mass concentration of stearic acid in the stearic acid-ethanol solution is 1-5%.
Specifically, in the step S3, the stirring time is 10-15min; the mass concentration of the aqueous solution of polyvinyl alcohol (PVA) is 1%, and the mass concentration of oleic acid in the oleic acid-ethanol solution is 0.5%; the dispersing operation is to process by ultrasonic wave.
The invention also provides the rod-shaped silver powder, which is prepared according to the preparation method of the rod-shaped silver powder, wherein the length of the rod-shaped silver powder is 10-50 mu m, and the diameter of the rod-shaped silver powder is 1.5-5 mu m.
The method for producing the rod-like silver powder according to the present invention will be described with reference to specific examples.
Example 1
The embodiment provides a preparation method of rod-shaped silver powder, which comprises the following steps:
s1, adding 5.5g of silver nitrate into 100mL of deionized water under the condition of mechanical stirring, adding 0.3g of PVP after fully mixing, and dripping ammonia water until the solution is clear after PVP is fully dissolved; adding 0.01g of sodium hydroxide, fully mixing, and then continuously dropwise adding ammonia water until the solution is clear to obtain a silver solution;
s2, pouring 11g of formalin into the silver solution prepared in the step S1 at one time under the condition of stirring at a constant temperature of 20 ℃; adding 5.5mL of stearic acid-ethanol solution after 1min, uniformly distributing stearic acid through stirring, filtering and washing to obtain first silver powder;
s3, filtering the first silver powder prepared in the step S2, dispersing the first silver powder in a polyvinyl alcohol aqueous solution with the mass concentration of 1%, stirring for 10min, filtering, dispersing the first silver powder in an oleic acid-ethanol solution with the mass concentration of 0.5%, stirring for 10min, filtering, and drying to obtain the rod-shaped silver powder.
Examples 2 to 4
Examples 2 to 4 respectively provide a preparation method of rod-shaped silver powder, compared with example 1, the dosage of sodium hydroxide in example 2 is adjusted from 0.01g to 0.05g, the dosage of formalin in example 3 is adjusted from 11g to 15g, the mode of adding formalin into silver solution in example 4 is adjusted from one-time pouring to be slowly dripped at the rate of 50mL/min, and the rest steps are identical to those in example 1, and are not repeated here.
Comparative examples 1 to 6
Comparative examples 1 to 6 respectively provided a method for preparing silver powder, compared with example 4, comparative example 1 was adjusted from 0.01g to 0.08g of sodium hydroxide, comparative examples 2 to 3 were adjusted from 0.3g to 0.05g and 1g of PVP, comparative examples 4 to 5 were adjusted from 11g to 5g and 20g of formalin, and comparative example 6 was adjusted from adding formalin to silver solution to adding silver solution to formalin, and the remaining steps were identical to those of example 1 and are not repeated here.
The morphology of the rod-like silver powder of examples 1 to 4 and the morphology of the silver powder of comparative example 1 and comparative example 5 were examined, and the results of the examination are shown in FIGS. 1 to 6.
According to the preparation method of the invention, as shown in fig. 1-4, when formalin is poured into silver solution at one time, the prepared rod-shaped silver powder is mixed with more silver nano particles in microsphere form, and the silver nano particles can play a role in welding the rod-shaped silver powder in the heat curing process, so that the silver powder has better conductivity and can be used as a conductive filler of thermosetting resin. The rod-shaped silver powder prepared by adopting a slow dropwise adding mode in the embodiment 4 has a structure similar to that of carbon fiber, is regular in rod-shaped structure and better in mechanical strength, and can be used in composite materials with certain requirements on conductivity and mechanical properties.
When the amount of sodium hydroxide used in comparative example 1 was higher than that in example 1, the pH of the reaction system was too high, and the oxidation-reduction reaction rate was too high, so that the reduced silver element could not grow into a regular rod shape, but became a mixed state of disordered particles of a size (fig. 5).
Too low or too high an amount of PVP in comparative examples 2-3 compared to example 4 may cause insufficient adsorption of PVP to a specific crystal plane or adsorption of all crystal planes, directly resulting in failure to obtain rod-like silver powder.
In comparison with example 4, the reducing agent in comparative example 4 was used in an insufficient amount, and silver ions could not be completely reduced; the excess of the reducing agent in comparative example 5 resulted in too high a reaction rate and too low a ratio of the rod-like silver powder (FIG. 6).
Comparative example 6 corresponds to a reaction of a very small amount of silver ions with a large excess of reducing agent, compared with example 4, and the principle is similar to comparative example 5, resulting in an excessively high reaction rate and an excessively low ratio of the rod-like silver powder.
In summary, according to the rod-shaped silver powder and the preparation method thereof disclosed by the invention, formalin is used as a reducing agent, the proportion of silver nitrate, PVP and formalin is controlled within a certain range, and the pH value of a reaction system and the rate of adding formalin into a silver solution are strictly controlled, so that the morphology and the size of the silver powder are controlled through the regulation and control of the oxidation-reduction reaction rate, and the rod-shaped silver powder with a regular structure and better electric conductivity is obtained. According to the invention, the silver ammine complex ion is reduced by formaldehyde, the rod-shaped silver powder which is in a more regular cylindrical shape and has the length of 10-50 mu m and the diameter of 1.5-5 mu m is prepared, the structure of the silver powder is highly similar to that of carbon fibers, and the silver powder can be used for replacing carbon fibers in composite materials with high requirements on electric conduction and heat conduction properties and can also be used in conductive adhesives and electromagnetic shielding coatings.
The above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made thereto without departing from the spirit and scope of the technical solution of the present invention.
Claims (5)
1. The preparation method of the rod-shaped silver powder is characterized by comprising the following steps of:
s1, adding a predetermined amount of silver nitrate into deionized water, uniformly mixing, adding a certain amount of polyvinylpyrrolidone, uniformly mixing, and then dropwise adding ammonia water until the solution is clear; adding a certain amount of sodium hydroxide, fully mixing, and then continuously dropwise adding ammonia water until the solution is clarified to obtain a silver solution; the mass ratio of the silver nitrate to the polyvinylpyrrolidone is (5-6): (0.2-0.3); the mass ratio of the silver nitrate to the sodium hydroxide is (5-6): (0-0.05); the mass ratio of the silver nitrate to the formalin is (5-6): (10-15);
s2, adding a predetermined amount of formalin into the silver solution prepared in the step S1 under the condition of constant temperature stirring at 0-25 ℃; adding a certain amount of stearic acid-ethanol solution, stirring, filtering and washing to obtain first silver powder; the mode of adding the formalin into the silver solution comprises one-time pouring and slow dripping; the slow dripping speed is 10-100mL/min;
s3, filtering the first silver powder prepared in the step S2, dispersing the first silver powder in a polyvinyl alcohol aqueous solution, stirring and filtering the first silver powder, dispersing the first silver powder in an oleic acid-ethanol solution, stirring the first silver powder for a certain time, filtering the first silver powder, and drying the first silver powder to obtain rod-shaped silver powder; the length of the rod-shaped silver powder is 10-50 mu m, and the diameter of the rod-shaped silver powder is 1.5-5 mu m.
2. The method for producing a rod-like silver powder according to claim 1, characterized in that: in the step S3, the stirring time is 10-15min.
3. The method for producing a rod-like silver powder according to claim 1, characterized in that: in the step S3, the mass concentration of the aqueous solution of polyvinyl alcohol is 1%, and the mass concentration of oleic acid in the oleic acid-ethanol solution is 0.5%.
4. The method for producing a rod-like silver powder according to claim 1, characterized in that: in step S2, the washing operation is to wash the silver powder surface pH to neutral using deionized water.
5. A rod-shaped silver powder, characterized in that the rod-shaped silver powder is produced according to the production method of the rod-shaped silver powder according to any one of claims 1 to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310666079.0A CN116372181B (en) | 2023-06-07 | 2023-06-07 | Rod-shaped silver powder and preparation method thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310666079.0A CN116372181B (en) | 2023-06-07 | 2023-06-07 | Rod-shaped silver powder and preparation method thereof |
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| Publication Number | Publication Date |
|---|---|
| CN116372181A CN116372181A (en) | 2023-07-04 |
| CN116372181B true CN116372181B (en) | 2023-09-05 |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105085709A (en) * | 2015-08-07 | 2015-11-25 | 河南农业大学 | Chitosan oligosaccharide quaternary ammonium salt derivative and method for preparing nanometer silver through same |
| CN105834450A (en) * | 2016-05-13 | 2016-08-10 | 浙江光达电子科技有限公司 | Preparing method for silver powder |
| CN105921765A (en) * | 2016-05-24 | 2016-09-07 | 中国科学院化学研究所 | Preparation method for particle-size-controllable rodlike silver powder |
| CN109482899A (en) * | 2018-12-07 | 2019-03-19 | 五邑大学 | A kind of surface modifying method of nano silver fibre |
| CN110560705A (en) * | 2019-10-29 | 2019-12-13 | 哈尔滨工业大学 | Method for controlling hydrothermal synthesis of silver nanowires by utilizing iron ions |
| CN111659901A (en) * | 2020-06-17 | 2020-09-15 | 中船重工黄冈贵金属有限公司 | Preparation method of submicron silver powder |
| CN114054769A (en) * | 2021-11-17 | 2022-02-18 | 广东羚光新材料股份有限公司 | Silver micro powder and preparation method and application thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20180055915A (en) * | 2015-12-03 | 2018-05-25 | 미쓰이금속광업주식회사 | Dendrite Awards Silver |
-
2023
- 2023-06-07 CN CN202310666079.0A patent/CN116372181B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105085709A (en) * | 2015-08-07 | 2015-11-25 | 河南农业大学 | Chitosan oligosaccharide quaternary ammonium salt derivative and method for preparing nanometer silver through same |
| CN105834450A (en) * | 2016-05-13 | 2016-08-10 | 浙江光达电子科技有限公司 | Preparing method for silver powder |
| CN105921765A (en) * | 2016-05-24 | 2016-09-07 | 中国科学院化学研究所 | Preparation method for particle-size-controllable rodlike silver powder |
| CN109482899A (en) * | 2018-12-07 | 2019-03-19 | 五邑大学 | A kind of surface modifying method of nano silver fibre |
| CN110560705A (en) * | 2019-10-29 | 2019-12-13 | 哈尔滨工业大学 | Method for controlling hydrothermal synthesis of silver nanowires by utilizing iron ions |
| CN111659901A (en) * | 2020-06-17 | 2020-09-15 | 中船重工黄冈贵金属有限公司 | Preparation method of submicron silver powder |
| CN114054769A (en) * | 2021-11-17 | 2022-02-18 | 广东羚光新材料股份有限公司 | Silver micro powder and preparation method and application thereof |
Non-Patent Citations (1)
| Title |
|---|
| 晶种法制备微米级球形银粉的超声诱导空化处理;李雪嵩等;黄金;第42卷(第10期);4-7 * |
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