阅读说明：本技术 一种产气灭弧粉及其制备方法 (Gas-generating arc-extinguishing powder and preparation method thereof ) 是由 黄云 周家兴 于 2021-06-24 设计创作，主要内容包括：本发明涉及一种产气灭弧粉及制备方法,该产气灭弧粉包括与空气导热系数相当的气相二氧化硅纳米粉,并加入无机阻燃剂、有机阻燃剂、改性三聚氰胺甲醛树脂和硅酸盐,以确保将灭弧粉的在电弧产生时能够释放出气体,降低金属离子浓度及碰撞几率,产生消游离作用而快速熄灭电弧。并保证产品的分断能力满足DC 300V400A要求。(The invention relates to gas-generating arc-extinguishing powder and a preparation method thereof, wherein the gas-generating arc-extinguishing powder comprises fumed silica nano powder with the same heat conductivity coefficient as air, and inorganic flame retardant, organic flame retardant, modified melamine formaldehyde resin and silicate are added to ensure that the arc-extinguishing powder can release gas when electric arc is generated, so that the concentration and collision probability of metal ions are reduced, and the arc is extinguished quickly by virtue of the dissociation elimination effect. And ensures that the breaking capacity of the product meets the requirement of DC300V 400A.)

1. The gas-generating arc extinguishing powder is characterized by comprising 5-30 wt% of fumed silica powder, 10-20 wt% of an inorganic flame retardant, 20-40 wt% of an organic flame retardant, 30-40 wt% of a nano-pore structure melamine-phenolic composite aerogel and 10-30 wt% of silicate.

2. The gas and arc extinguishing powder of claim 1, wherein the fumed silica powder has a mesh size of 500-1000 mesh.

3. The gas-generating arc extinguishing powder of claim 2, wherein the inorganic flame retardant is Al (OH)₃Or Mg (OH).

4. A gas and arc suppressing powder as claimed in claim 1, 2 or 3 wherein said silicate is magnesium silicate.

5. The gas and arc extinguishing powder according to claim 1, 2 or 3, wherein the organic flame retardant is melamine modified urea formaldehyde resin.

6. Gas-and arc-extinguishing powder according to claim 1, 2 or 3, characterized in that the nanoporous melamine-phenolic composite aerogel is obtained by compounding resorcinol-formaldehyde and melamine, followed by solvent displacement with ethanol and supercritical drying.

7. The gas-generating arc-extinguishing powder according to claim 1, 2 or 3, wherein the gas-generating arc-extinguishing powder is used for filling an insulating tube of a tubular fuse.

8. A process for the production of gas-generating arc-extinguishing powders according to any of claims 1 to 5, characterized in that it comprises the following steps,

(1) weighing materials: weighing various raw materials with required mass according to a formula proportion for later use;

(2) adding an inorganic flame retardant into fumed silica powder: mixing and granulating inorganic flame retardant powder with required mass ratio and the fumed silica powder obtained in the step 1) in a granulator to ensure that the inorganic flame retardant powder is uniformly coated on the surface of the fumed silica powder;

(3) adding silicate: mixing silicate powder with required mass ratio and the coated powder obtained in the step (2) in a granulator for granulation, so that the silicate powder is uniformly coated on the surface of the powder;

(4) adding an organic flame retardant: mixing and granulating the organic flame retardant powder with the required mass ratio and the coated powder obtained in the step (3) in a granulator to uniformly coat the organic flame retardant powder on the surface of the powder;

(5) adding the melamine phenolic aldehyde composite aerogel with the nano-pore structure: resorcinol: formaldehyde: melamine: ethanol: mixing acids according to a molar ratio of 1: 3-4: 0.02-0.2: 10-12: 0.06-0.08, magnetically stirring, placing the mixture in an oven for gelation, uniformly preparing melamine-doped resorcinol-formaldehyde sol, grinding the melamine-doped resorcinol-formaldehyde sol into powder by using an agate mortar, screening out 80-120 meshes by using a screen, mixing the coated powder obtained in the step (4) with the coated powder in a granulator for granulation, and uniformly coating the melamine-phenolic composite aerogel with a nano-pore structure on the surface of the powder to obtain a spherical arc extinguishing material;

(6) drying and baking: and (5) placing the spherical arc-extinguishing material obtained in the step (5) into a drying oven to be baked for a period of time, and then taking out.

9. The preparation method according to claim 8, wherein the nanoporous melamine phenolic composite aerogel in the step (5) is prepared according to the following steps: resorcinol: formaldehyde: melamine: ethanol: the acid is added in a molar ratio of 1:3:0.1:11: 0.06.

10. The production method according to claim 9, wherein the drying and baking conditions in the step (6) are: baking at 125 deg.C for 20min or 100 deg.C for 30 min.

Technical Field

The invention relates to arc extinguishing powder for arc extinguishing of a tubular fuse, in particular to arc extinguishing powder with a gas production effect and a preparation method of the arc extinguishing powder.

Background

The surface-mounted tubular micro fuse product with the breaking capacity of DC300V400A or more generally needs to be filled with arc extinguishing materials to extinguish electric arcs generated when metal melts are fused by overcurrent and buffer huge impact on a fuse shell caused by explosion pressure generated at the moment of fusing.

Besides generating a large amount of heat energy during the breaking process, the melt is accompanied by two forms of pressure: the melt is gasified and arcing to generate explosion pressure in a pulse form and arcing pressure generated in the whole arcing period. The conventional arc-extinguishing material can generally carry out physical and chemical changes such as pyrolysis, melting, evaporation, sublimation, erosion and the like on the material under the action of high-temperature heat flow, so that the heat is taken away by causing mass consumption on the surface of the material, and the influence of heat energy generated when a melt is cut off is reduced. However, due to the existence of high temperature, conventional arc extinguishing materials such as quartz sand, silica gel, thermosetting resin, glass coating and the like do not have elastic buffering capacity for explosion pressure, and pyrolysis gas generated by an arc extinguishing component can cause pressure rise inside an arc extinguishing device, so that poor breaking of a fuse is easily caused during continuous arcing.

The existing low-voltage fuse generally uses high-purity quartz sand as an arc extinguishing material under the conditions of high voltage and high breaking capacity, mainly because the quartz sand has higher heat conductivity and insulating performance and has a large contact area with an electric arc, the quartz sand is convenient to absorb the energy of the electric arc, so that the electric arc can be rapidly cooled, and the fuse can safely break a short-circuit current. However, the quartz sand as a filler of the fuse has the following problems: the quartz sand is used as a mineral substance, is greatly influenced by a production place, and is difficult to remove metal impurities such as iron and the like; the surface of the quartz sand is rough, so that the uniformity of the filling density is difficult to control during the assembly of the fuse, and the breaking effect is further influenced; the thermal conductivity is large, the heat dissipation is fast, and the fuse is difficult to break and overload at low power.

Meanwhile, as electronic equipment products develop towards miniaturization and portability, the space of a circuit board is reduced, the volume of a fuse is further reduced, and meanwhile, the fuse needs to be subjected to chip mounting, high voltage resistance, high current and high breaking capacity. Therefore, there is a need to develop a new arc-extinguishing material.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to provide novel gas-generating arc-extinguishing powder for solving the technical problem of how to reduce the concentration and collision probability of metal ions and generate dissociation elimination effect to quickly extinguish electric arcs.

The invention also provides a preparation method of the arc extinguishing powder.

In order to achieve the purpose, the arc extinguishing powder adopts the following technical scheme:

gas-generating arc extinguishing powder comprises 5-30 wt% of fumed silica powder, 10-20 wt% of an inorganic flame retardant, 20-40 wt% of an organic flame retardant, 30-40 wt% of a nano-pore structure melamine phenolic composite aerogel and 10-30 wt% of silicate.

Furthermore, the mesh number of the fumed silica powder is 500-1000 meshes.

Further, the inorganic flame retardant is Al (OH)₃Or Mg (OH).

Further, the silicate is magnesium silicate.

Further, the organic flame retardant is melamine modified urea-formaldehyde resin.

Further, the melamine-phenolic composite aerogel with the nano-pore structure is prepared by compounding resorcinol-formaldehyde and melamine, and then performing ethanol solvent replacement and supercritical drying.

Furthermore, the gas-generating arc-extinguishing powder is used for filling an insulating tube of the tubular fuse.

The preparation method of the gas-generating arc-extinguishing powder can adopt the following technical scheme:

comprises the following steps of (a) carrying out,

(1) weighing materials: weighing various raw materials with required mass according to a formula proportion for later use;

(2) adding an inorganic flame retardant into fumed silica powder: mixing and granulating inorganic flame retardant powder with required mass ratio and the fumed silica powder obtained in the step 1) in a granulator to ensure that the inorganic flame retardant powder is uniformly coated on the surface of the fumed silica powder;

(3) adding silicate: mixing silicate powder with required mass ratio and the coated powder obtained in the step (2) in a granulator for granulation, so that the silicate powder is uniformly coated on the surface of the powder;

(4) adding an organic flame retardant: mixing and granulating the organic flame retardant powder with the required mass ratio and the coated powder obtained in the step (3) in a granulator to uniformly coat the organic flame retardant powder on the surface of the powder;

(5) adding the melamine phenolic aldehyde composite aerogel with the nano-pore structure: resorcinol: formaldehyde: melamine: ethanol: mixing acids according to a molar ratio of 1: 3-4: 0.02-0.2: 10-12: 0.06-0.08, magnetically stirring, placing the mixture in an oven for gelation, uniformly preparing melamine-doped resorcinol-formaldehyde sol, grinding the melamine-doped resorcinol-formaldehyde sol into powder by using an agate mortar, screening out 80-120 meshes by using a screen, mixing the coated powder obtained in the step (4) with the coated powder in a granulator for granulation, and uniformly coating the melamine-phenolic composite aerogel with a nano-pore structure on the surface of the powder to obtain a spherical arc extinguishing material;

(6) drying and baking: and (5) placing the spherical arc-extinguishing material obtained in the step (5) into a drying oven to be baked for a period of time, and then taking out.

Further, the melamine phenolic aldehyde composite aerogel with the nano-pore structure in the step (5) is prepared by the following steps: resorcinol: formaldehyde: melamine: ethanol: the acid is added in a molar ratio of 1:3:0.1:11: 0.06.

Further, the drying and baking conditions in the step (6) are as follows: baking at 125 deg.C for 20min or 100 deg.C for 30 min.

Has the advantages that: compared with the prior art, the gas-generating arc-extinguishing powder provided by the invention has the following beneficial effects.

1. Is non-toxic, harmless, environment-friendly and safe. The inorganic flame retardant in the formula is Al (OH)₃It is a clean flame retardant with low cost and without smoke or corrosive or toxic gas generation during combustion.

2. And (4) rapidly quenching the arc. The melamine modified urea-formaldehyde resin, the nano-pore structure melamine phenolic aldehyde composite aerogel and the silicate are high breaking capacity arc extinguishing powder materials with main crystal phases, so that under the high-temperature firing of electric arcs in breaking, the amino resin can not only decompose a large amount of hydrogen, nitrogen, water vapor, carbon monoxide, carbon dioxide and other gases beneficial to arc extinguishing, but also is light in carbonization. Inorganic flame retardant Al (OH)₃、Mg(OH)₂Under the high-temperature ignition of electric arc, water vapor is generated at 210-220 ℃, carbon monoxide and hydrogen are generated by the action of the water vapor and the carbon, the two endothermic reactions play roles of cooling the electric arc, accelerating the dissociation removal, facilitating the arc extinction, and removing the carbon deposited on the surface to generate CO₂Gas and contentH easy to extinguish arc₂. And the internal pressure of the product is increased, the concentration and collision probability of metal ions are reduced, and the dissociation effect is generated to quickly extinguish the electric arc.

3. The arc quenching capability is strong. At present, the capacity of arc-extinguishing materials in the industry is mostly about DC250V 100A, with the development of electronic equipment products towards miniaturization and portability, the space of a circuit board is reduced, the volume of a fuse is further reduced, and meanwhile, the fuse needs to be pasted with a chip, high in voltage resistance, large in current and high in breaking capacity. The breaking capacity of the gas-generating arc-extinguishing material prepared by the invention can reach DC300V400A and above.

Drawings

FIG. 1 is an appearance diagram of Fujian product 100-200 mesh quartz sand in the prior art;

FIG. 2 is a waveform diagram of a test conducted at DC300V400A using 100-200 mesh quartz sand produced by Fujian province in the prior art as a filling material;

FIG. 3 is an appearance diagram of the gas-generating arc-extinguishing material of 100-200 mesh in the present invention;

FIG. 4 is a waveform diagram of 100-200 mesh gas-generating arc-extinguishing material prepared in example 1 of the present invention tested at DC300V 400A.

Detailed Description

The invention provides a gas-generating arc-extinguishing powder

The arc extinguishing powder with the low thermal conductivity coefficient comprises 5-30 wt% of fumed silica powder, 10-20 wt% of an inorganic flame retardant, 20-40 wt% of an organic flame retardant, 30-40 wt% of a nano-pore structure melamine phenolic composite aerogel and 10-30 wt% of silicate.

The fumed silica powder is micron-sized powder with the mesh number of about 500-1000 meshes, and the main characteristic is that the heat conductivity coefficient of the fumed silica powder is equivalent to that of air; the inorganic flame retardant, such as Mg (OH)2, Al (OH)3 and the like, such as Al (OH)3, does not smoke or generate corrosive or toxic gas during combustion, has low cost and is a clean flame retardant. Al (OH)3 begins to generate water vapor at 210 ℃ to 220 ℃ as follows:

the water vapor and the carbon act simultaneously to generate carbon monoxide and hydrogen, and the formula is as follows:

these two endothermic reactions serve to cool the arc, accelerate deionization, facilitate arc quenching, and remove carbon deposited on the surface, produce CO2 gas and H2 which extinguishes the arc more easily. Al (OH)3 is an inert compound, and can form a good insulating layer, so that the insulation resistance of the product is recovered quickly. The organic flame retardant, such as melamine, melamine modified urea-formaldehyde resin, melamine cyanurate, organic silicon and the like, for example, the melamine modified urea-formaldehyde resin is formed by copolycondensation of urea, melamine and formaldehyde. From the viewpoint of their molecular structures, the carbon atom contents were low, 12.5%, 20%, and 22%, respectively. Therefore, the condensed amino resin has low carbon atom content and high hydrogen and nitrogen atom content, so that under the high-temperature burning of the electric arc, the amino resin can not only decompose a large amount of gases which are beneficial to arc extinguishing, such as hydrogen, nitrogen, water vapor, carbon monoxide, carbon dioxide and the like, but also has light carbonization; the melamine-phenolic composite aerogel with the nano-pore structure is prepared by compounding RF (resorcinol-formaldehyde) and melamine, and then performing ethanol solvent replacement and supercritical drying. The silicate, such as magnesium silicate Mg3 [ Si4O10 ] (OH)2, iron silicate, aluminum silicate, etc., has excellent physical properties such as lubricity, anti-sticking property, flow aid, fire resistance, insulation property, high melting point, chemical inactiveness, good covering power, softness, good gloss, strong adsorption power, etc.

The preparation method of the gas-generating arc-extinguishing powder can adopt the following technical scheme:

comprises the following steps of (a) carrying out,

(1) weighing materials: weighing various raw materials with required mass according to a formula proportion for later use;

(2) adding an inorganic flame retardant into fumed silica powder: mixing and granulating inorganic flame retardant powder with required mass ratio and the fumed silica powder obtained in the step 1) in a granulator to ensure that the inorganic flame retardant powder is uniformly coated on the surface of the fumed silica powder;

(3) adding silicate: mixing silicate powder with required mass ratio and the coated powder obtained in the step (2) in a granulator for granulation, so that the silicate powder is uniformly coated on the surface of the powder;

(4) adding an organic flame retardant: mixing and granulating the organic flame retardant powder with the required mass ratio and the coated powder obtained in the step (3) in a granulator to uniformly coat the organic flame retardant powder on the surface of the powder;

(5) adding the melamine phenolic aldehyde composite aerogel with the nano-pore structure: resorcinol: formaldehyde: melamine: ethanol: mixing acids according to a molar ratio of 1: 3-4: 0.02-0.2: 10-12: 0.06-0.08, magnetically stirring, placing the mixture in an oven for gelation, uniformly preparing melamine-doped resorcinol-formaldehyde sol, grinding the melamine-doped resorcinol-formaldehyde sol into powder by using an agate mortar, screening out 80-120 meshes by using a screen, mixing the coated powder obtained in the step (4) with the coated powder in a granulator for granulation, and uniformly coating the melamine-phenolic composite aerogel with a nano-pore structure on the surface of the powder to obtain a spherical arc extinguishing material;

(6) drying and baking: and (5) placing the spherical arc-extinguishing material obtained in the step (5) into a drying oven to be baked for a period of time, and then taking out.

The technical effect of the gas-generating arc-extinguishing powder provided by the invention is illustrated by specific examples and test conclusions.

Example 1:

weighing fumed silica powder in a container according to the mass ratio: melamine modified urea resin: adding 5 wt% of magnesium silicate, 25 wt% of magnesium silicate and 30 wt% of magnesium silicate into the container while stirring, then pouring into a granulator for granulation, sieving out the magnesium silicate by a 100-200 mesh sieve, and placing the magnesium silicate into another clean container to obtain the semi-finished spherical powder 1. And (5) adding semi-finished spherical powder 1 in the mass ratio according to the step (4): al (OH)₃Mixing 60 wt% and 10 wt% in a container containing semi-finished spherical powder 1, stirring with a glass rod, mixing, adding into a granulator, granulating again, and passing through a granulator 1And screening out the powder by a screen of 00-200 meshes to obtain powder 2. Then, the resorcinol: formaldehyde: melamine: ethanol: mixing acids according to a molar ratio of 1:3:0.1:11:0.06, magnetically stirring, placing in an oven for gelation, uniformly preparing melamine doped resorcinol-formaldehyde (N-RF) sol, grinding into powder by using an agate mortar, screening out powder 3 with 80-120 meshes by using a screen, weighing 30 wt% of the powder, placing the powder 2 and the powder 3 in a granulator for mixing granulation, uniformly coating the surface of the powder 2 with the melamine-phenolic composite aerogel powder 3 with a nano-pore structure, obtaining a spherical arc extinguishing material, and placing in a tray. And putting the arc extinction powder into an oven to be baked for 20min at 125 ℃ to obtain the arc extinction powder with the mesh number of 100-200.

The breaking capacity test after filling is carried out on the surface-mounted tubular fuse product with the size of 10mm x 3.2mm and the rated current of 40A, the product obtained by assembling Ag 100% sheets is used for carrying out the breaking capacity test of DC300V400A on the product filled with the arc extinguishing powder with the formula of the embodiment, and the requirement of the breaking condition can be met. The test waveform is shown in fig. 4.

As a comparative example, a surface-mounted tubular fuse product with the size of 10mm x 3.2mm and the rated current of 40A is filled with 100-200 mesh quartz sand of Fujian in the prior art and then is subjected to a DC300V400A breaking capacity test, the breaking condition cannot be met, the fuse tube body is burst, and the test waveform is shown in FIG. 2.

Example 2:

weighing fumed silica in a container according to the mass ratio: melamine modified urea resin: 10 wt% of magnesium silicate and 20 wt% of magnesium silicate are added into the container while stirring, then poured into a granulator for granulation, sieved out by a 100-200 mesh sieve and placed into another clean container to obtain a semi-finished spherical powder 1. And (5) adding semi-finished spherical powder 1 in the mass ratio according to the step (4): mg (OH)₂Mixing 50 wt% and 15 wt% in a container containing semi-finished spherical powder 1, stirring and mixing with a glass rod, pouring into a granulator again for secondary granulation, sieving with a 100-200 mesh sieve to obtain powder 2, and sieving m-xylylene diaminePhenol: formaldehyde: melamine: ethanol: mixing acids according to a molar ratio of 1:4:0.08:10:0.07, magnetically stirring, placing in an oven for gelling, uniformly preparing melamine-doped resorcinol-formaldehyde (N-RF) sol, grinding into powder by using an agate mortar, screening out 100-120 meshes of powder 3 by using a screen, weighing 35 wt% of the powder, placing the powder 2 and the powder 3 in a granulator for mixing granulation, uniformly coating the surface of the powder 2 with the nano-pore structure melamine-phenolic composite aerogel powder 3, obtaining a spherical arc extinguishing material, and placing in a tray. And putting the arc extinction powder into an oven to be baked for 30min at 100 ℃ to obtain the arc extinction powder with the mesh number of 100-200.

The breaking capacity test after filling is carried out on the surface-mounted tubular fuse product with the size of 10mm x 3.2mm and the rated current of 40A, the product obtained by assembling Ag 100% sheets is subjected to the breaking capacity test of DC300V400A on the product filled with the arc extinguishing powder with the formula of the embodiment, and the requirement of the breaking condition can be met.

Example 3:

weighing fumed silica in a container according to the mass ratio: melamine modified urea resin: adding 15 wt% of magnesium silicate and 25 wt% of magnesium silicate into the container while stirring, then pouring into a granulator for granulation, sieving out the magnesium silicate by a 100-200 mesh sieve, and placing the magnesium silicate into another clean container to obtain the semi-finished spherical powder 1. And (5) adding semi-finished spherical powder 1 in the mass ratio according to the step (4): al (OH)₃Mixing 50 wt% and 10 wt% in a container containing semi-finished spherical powder 1, stirring and mixing fully with a glass rod, pouring into a granulator again for secondary granulation, sieving by a 100-200 mesh sieve to obtain powder 2, and mixing resorcinol: formaldehyde: melamine: ethanol: mixing acid according to a molar ratio of 1:3.5:0.2:12:0.08, magnetically stirring, placing in an oven for gelling, uniformly preparing melamine-doped resorcinol-formaldehyde (N-RF) sol, grinding into powder by using an agate mortar, screening out 100-120 meshes of powder 3 by using a screen, weighing 40 wt% of powder, placing powder 2 and powder 3 in a granulator for mixing and granulation, and enabling the nanopore-structure melamine-phenolic composite aerogelThe glue powder 3 is uniformly coated on the surface of the powder 2 to obtain the spherical arc extinguishing material, and the spherical arc extinguishing material is placed in a tray. And putting the arc extinction powder into an oven to be baked for 20min at 125 ℃ to obtain the arc extinction powder with the mesh number of 100-200.

The breaking capacity test after filling is carried out on the surface-mounted tubular fuse product with the size of 10mm x 3.2mm and the rated current of 40A, the product obtained by assembling Ag 100% sheets is used for carrying out the breaking capacity test of DC300V400A on the product filled with the arc extinguishing powder with the formula of the embodiment, and the requirement of the breaking condition can be met.

In addition, the present invention has many specific implementations and ways, and the above description is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be construed as the protection scope of the present invention.