CN113845818A

CN113845818A - Water-based heavy-duty anticorrosive paint and preparation method and application thereof

Info

Publication number: CN113845818A
Application number: CN202111161867.1A
Authority: CN
Inventors: 蔡子祥; 唐朝运; 薛慧
Original assignee: Wuxi Putian Iron Core Co Ltd
Current assignee: Wuxi Putian Iron Core Co Ltd
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2021-12-28

Abstract

The invention discloses a water-based heavy-duty anticorrosive paint, and a preparation method and application thereof. The water-based heavy-duty anticorrosive paint comprises the following components in percentage by weight: 20-40% of water-based phenolic epoxy resin, 0.5-2% of anti-flash rust agent, 5-15% of anti-rust pigment, 5-15% of titanium dioxide, 10-20% of barium sulfate, 5-15% of mica powder, 0-5% of talcum powder, 0-5% of calcium carbonate, 3-6% of dispersing agent, 0.5-1.0% of wetting agent, 0-0.5% of flatting agent I, 0-0.5% of flatting agent II, 3-30% of organic solvent, 0.2-1.0% of heat stabilizer, 0.1-1% of colorant, 0.2-0.5% of defoaming agent, 0.2-0.5% of thickening agent and 5-20% of water. The water-based heavy-duty anticorrosive coating prepared by the invention can be used for transformer cores, can resist temperature of 210 ℃ for 72 hours, and can resist neutral salt spray corrosion for more than 720 hours before a temperature resistance test.

Description

Water-based heavy-duty anticorrosive paint and preparation method and application thereof

Technical Field

The invention relates to the technical field of transformer core anticorrosive coatings, in particular to a water-based heavy-duty anticorrosive coating and a preparation method and application thereof.

Background

The anticorrosive paint for the transformer core belongs to a special anticorrosive paint, but as the industry of the transformer accumulates for many years, the quality of the product can be ensured by using a paint product checked and confirmed by a terminal customer. However, with the successive release of national environmental protection policies, the development trend of the transformer core coating industry is that water-based paint replaces commonly used oil-based paint.

The water paint in the current market has certain application in the field of corrosion prevention, but relates to the field of heavy corrosion prevention and the industry field which puts forward special resistance requirements to coatings, and most of the water paint can not meet the comprehensive performance requirements put forward by practical application. The transformer core has high requirement on the corrosion resistance of the coating, and simultaneously the water-based coating is required to meet the high-temperature impact possibly suffered by the core in use and other special performance requirements. The current water-based paint can meet the conventional corrosion prevention requirement of the iron core: the product can resist temperature of 180 ℃ for 72h, resist neutral salt spray for more than 500h before the temperature resistance test, and resist neutral salt spray for more than 300h after the temperature resistance test is bored. The resin selected in the conventional market, the product which can resist 210 ℃ for 24h without obvious pulverization is difficult to find, and the single coating can resist more than 720h of neutral salt fog, so that the water-based paint is not a small challenge. The research and development of the special water-based heavy-duty anticorrosive paint for the transformer iron core are problems which must be faced and solved by the iron core industry. No corresponding product in the existing market can completely meet the temperature resistance of 210 ℃ for 72h required in heavy corrosion prevention of transformer cores, and meanwhile, the neutral salt spray corrosion resistance is over 720h before a temperature resistance test, and the neutral salt spray corrosion resistance is kept over 360h after the temperature resistance test.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a water-based heavy-duty anticorrosive paint, and a preparation method and application thereof. According to the invention, the water-based heavy-duty coating for the transformer core, which can simultaneously realize high temperature resistance and salt mist resistance, is prepared by optimizing the raw materials, the proportion and the preparation method of the water-based coating, and the performance requirements of temperature resistance of 210 ℃ for 72h, neutral salt mist corrosion resistance of more than 720h before a temperature resistance test and neutral salt mist corrosion resistance of more than 360h after the temperature resistance of 210 ℃ for 72h can be met when the water-based heavy-duty coating is used for coating the transformer core.

The technical scheme of the invention is as follows:

the water-based heavy-duty anticorrosive paint comprises the following components in percentage by weight: 20-40% of water-based phenolic epoxy resin, 0.5-2% of anti-flash rust agent, 5-15% of anti-rust pigment, 5-15% of titanium dioxide, 10-20% of barium sulfate, 5-15% of mica powder, 0-5% of talcum powder, 0-5% of calcium carbonate, 3-6% of dispersing agent, 0.5-1.0% of wetting agent, 0-0.5% of flatting agent I, 0-0.5% of flatting agent II, 3-30% of organic solvent, 0.2-1.0% of heat stabilizer, 0.1-1% of colorant, 0.2-0.5% of defoaming agent, 0.2-0.5% of thickening agent and 5-20% of water;

the epoxy equivalent of the water-based novolac epoxy resin is 250 g/eq-1000 g/eq.

Further, the anti-rust pigment is at least two of zinc phosphate, zinc bismuthate, zinc phosphomolybdate, aluminum tripolyphosphate, zinc strontium phosphate and zinc silicate.

Further, the titanium dioxide is one or more of dupont 706, dupont 902, Dongjia 2377 and python 996.

Further, the barium sulfate is one or two of precipitated barium sulfate and natural barium sulfate; the mesh number of the natural barium sulfate is 1250-4000 meshes; the mesh number of the mica powder is 1250-4000 meshes; the mesh number of the talcum powder is 1250-4000 meshes; the mesh number of the calcium carbonate is 1250-4000 meshes; the dispersant is a block polymer dispersant.

Further, the wetting agent is one or more of a polyether modified organic silicon wetting agent and a fluorine modified organic silicon wetting agent; the leveling agent I is a polyether modified organic silicon leveling agent; and the leveling agent II is an acrylic leveling agent.

Further, the organic solvent is one or more of ether and alcohol; the ether is at least two of propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, propylene glycol butyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, diethylene glycol methyl ether, diethylene glycol butyl ether, diethylene glycol propyl ether and diethylene glycol ethyl ether; the alcohol is at least two of ethanol, isopropanol and n-butanol; the mass fraction of ether in the organic solvent is 66.7-100%, and the mass fraction of alcohol is 0-33.3%; the colorant is one or more of water-based carbon black pulp, water-based blue pulp, water-based iron yellow pulp, water-based iron red pulp, water-based green pulp, water-based purple pulp and water-based bright red pulp; the defoaming agent is one or more of silicone defoaming agent, mineral oil defoaming agent and acetylene glycol defoaming agent; the thickening agent is one or more of inorganic bentonite and hydroxy cellulose.

A preparation method of the water-based heavy-duty anticorrosive paint comprises the following steps:

(1) sequentially adding 20-40 wt% of water-based novolac epoxy resin, 5-15 wt% of water and 3-6 wt% of a dispersing agent according to the weight percentage, adjusting the dispersing speed to 600-2000 rpm after first dispersing, then sequentially adding 5-15 wt% of titanium dioxide, 10-20 wt% of barium sulfate, 5-15 wt% of mica powder, 0-5 wt% of calcium carbonate, 0-5 wt% of talcum powder, 5-15 wt% of antirust pigment, 0.1-1 wt% of colorant and 0.1-0.3 wt% of defoaming agent, dispersing for 20-60 min again to obtain original slurry, grinding and filtering to obtain slurry I;

(2) dispersing at 300-800 rpm, adding 0.5-1.0% of wetting agent, 3-30% of organic solvent, 0.2-1.0% of heat stabilizer, 0-0.5% of flatting agent I, 0-0.5% of flatting agent II, 0.2-0.5% of thickening agent and 0.5-2% of flash rust inhibitor into the slurry I prepared in the step (1), dispersing for 10-30 min, then adding 0-5% of water and 0.1-0.2% of defoaming agent, and defoaming after re-dispersing to obtain the water-based heavy anti-corrosion coating.

Further, in the step (1), the speed of the first dispersing is 300-800 rpm, and the time is 5-10 min; the grinding is to place the original slurry in a grinding cylinder, add zirconia beads with the weight 1.5-3.5 times of that of the original slurry under the cooling of circulating cooling water, and grind for 30-200 min at the rotating speed of 2000-5000 rpm; the fineness of the slurry I is less than or equal to 15 mu m.

Further, in the step (2), the re-dispersing speed is 400-1000 rpm, and the time is 10-20 min; the defoaming speed is 100-300 rpm, and the defoaming time is 10-30 min.

The application of the water-based heavy-duty anticorrosive paint is characterized in that the water-based heavy-duty anticorrosive paint is used for transformer cores.

The heat stabilizer belongs to a free radical capturing stabilizer, and can be combined with free radicals to slow down the accelerated aging process when the resin is subjected to accelerated aging of the free radicals generated by pyrolysis so as to stabilize the resin structure.

According to the invention, oily resin capable of meeting the highest tolerance requirement of the transformer core is taken as a reference, the oily resin is hydrated, the temperature resistance of the coating is improved by a special auxiliary agent, the salt spray corrosion resistance of the coating is not influenced, and the product is finally and successfully prepared by continuously researching and developing, continuously selecting materials and formula proportions.

The phenolic epoxy resin selected by the water-based heavy-duty anticorrosive coating prepared by the invention is matched with the amine curing agent with a polycyclic structure, so that the water-based heavy-duty anticorrosive coating has good high-temperature resistance, the self temperature resistance of the resin can reach 190 ℃ for 72 hours through testing, a coating film is not weightless and cracked, the adhesive force of a steel substrate is not reduced, and when the film forming effect is optimal, the salt spray performance can reach 480 hours; but after 210 ℃ for 72h, the coating has obvious weight loss after temperature resistance, obvious cracking and obvious yellowing. In order to solve the high temperature resistance of the coating, the water dispersible heat stabilizer is added into the raw materials, so that the coating can resist the high temperature of 210 ℃ for 72h without weight loss, cracking and slight yellowing after a high temperature resistance test, the defect of the high temperature resistance of the resin is effectively solved, and meanwhile, the water dispersible heat stabilizer can not reduce the salt spray resistance and other anti-corrosion properties of the coating.

In order to solve the problem that the salt spray resistance of the traditional coating is not enough to reach 720h, the invention specially selects special antirust pigments, such as ammonium zinc phosphate, strontium phosphate, calcium aluminum polyphosphate silicate compound, zinc silicate and the like, except zinc phosphate and aluminum tripolyphosphate, for example, the ammonium zinc phosphate can have certain reactivity with an epoxy group of epoxy resin, so that the pigment and a resin matrix have better fusion property, and a coating film is more compact and difficult to corrode; the mica powder as a barrier filler also has the effect of blocking the external erosion, when the filler and the pigment are organically combined with a flaky structure in a spherical structure and the particle size is organically combined, the filling compactness of the whole coating can be greatly improved, and particularly, when the coating is subjected to high temperature again and matrix resin is carbonized and cracked, the salt spray performance can be still maintained; the silicate, the calcium aluminum polyphosphate compound and the strontium salt are introduced, so that the integral coating has an antirust mechanism except for zinc phosphate and aluminum phosphate for rust protection, the vacancy of failure of the anticorrosion principle of the zinc phosphate and the aluminum tripolyphosphate is filled, and the anticorrosion performance of the coating is further effectively improved.

The beneficial technical effects of the invention are as follows:

(1) according to the invention, the water-based novolac epoxy resin is matched with the water-based amine curing agent with good high-temperature resistance and salt spray resistance, so that the prepared water-based heavy anti-corrosion coating has strong salt spray resistance and good high-temperature resistance, and the obtained coating has excellent salt spray resistance before and after a high-temperature resistance test.

(2) According to the invention, through reasonable proportioning of the high salt spray resistant antirust pigment, the dispersant, the stabilizer and other components, and simultaneously considering the pigment ratio (the weight ratio of the pigment filler to the resin) of the whole coating, the prepared coating can simultaneously meet the salt spray resistance and the high temperature resistance.

(3) The invention uses the hyperdispersant with high dispersibility and stability, ensures the fineness and stability of the dispersion of the rest fillers in the coating, simultaneously ensures that the anti-coarsening phenomenon cannot occur in the storage process, and ensures that the powder is stably dispersed in the coating and can pass through two forms of an electric double layer and a steric hindrance; the used solvents are all environment-friendly solvents, can assist the effective film formation of the water-based novolac epoxy resin and the amine curing agent, achieve higher reaction degree, and further enable the formed film to have good sealing property. The addition of the aqueous heat stabilizer can prevent the aging reaction from continuing.

(4) According to the invention, through optimizing the components such as the dispersing agent, the stabilizing agent, the anti-rust pigment and the like and the proportion, the heavy anti-corrosion coating which can resist temperature of 210 ℃ for 72 hours, can resist salt spray for more than 720 hours before a temperature resistance test and resist temperature for more than 360 hours after the temperature resistance test can meet the performance requirements of the iron core such as severe temperature resistance, corrosion resistance and the like.

Drawings

FIG. 1 is a drawing of a dried paint object in example 1 of the present invention.

FIG. 2 is a comparison of the temperature resistance of steel plates sprayed with the coating prepared in comparative example 2 of the present invention before and after the temperature resistance test.

FIG. 3 is a graph comparing 480h direct salt spray and 240h salt spray after 210 ℃ 72h temperature resistance of a steel plate sprayed with the coating prepared in comparative example 3 of the invention.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and examples.

Example 1

The water-based heavy-duty anticorrosive paint comprises the following components in percentage by weight: 20% of water-based novolac epoxy resin, 0.5% of anti-flash rust agent, 5% of anti-rust pigment (zinc bismuthate phosphate 3% and zinc phosphate 2%), 10% of titanium dioxide (DuPont 706), 13.3% of barium sulfate (natural barium sulfate, mesh number 2000), 15% of mica powder (mesh number 1250), 2% of calcium carbonate, 3% of talcum powder, 6% of dispersing agent (EDAPAN 490 of Germany and Ming chemical industry), 0.5% of wetting agent (TEGO 270), 0.5% of flatting agent I (TEGO4100), 3% of organic solvent (propylene glycol methyl ether 1%, dipropylene glycol methyl ether 2%), 0.2% of heat stabilizer, 0.6% of coloring agent (water-based carbon black slurry), 0.2% of defoaming agent TEGO W902%, 0.2% of inorganic bentonite thickener and 20% of water; the water-based novolac epoxy resin is F-51, the solid content is more than or equal to 55 percent, and the epoxy equivalent is 250-1000 g/eq.

The preparation method of the water-based heavy-duty anticorrosive paint comprises the following steps:

(1) according to the weight percentage, 20% of water-based novolac epoxy resin, 15% of water and 6% of dispersing agent are sequentially added, after the materials are dispersed for 10min at the rotating speed of 300rpm, the dispersing speed is adjusted to 600rpm, 10% of titanium dioxide, 13.3% of barium sulfate, 15% of mica powder, 2% of calcium carbonate, 3% of talcum powder and 5% of antirust pigment are sequentially added, 0.6% of water-based carbon black slurry and 0.1% of defoaming agent are added, after the materials are dispersed at the rotating speed of 600rpm at a high speed for 60min, the original slurry is obtained, the original slurry is transferred to a grinding cylinder, under the cooling of circulating cooling water, zirconia beads with the weight being 1.5 times that of the slurry are added, the materials are ground for 30min at the rotating speed of 5000rpm, the zirconia beads are filtered, and the slurry I is obtained, and the fineness is less than or equal to 15 mu m.

(2) While dispersing at the rotating speed of 300rpm, sequentially adding 0.5% of wetting agent, 3% of organic solvent, 0.2% of heat stabilizer, 0.5% of flatting agent I, 0.2% of thickening agent and 0.5% of anti-flash rust agent into the slurry I prepared in the step (1), after dispersing for 30min, sequentially adding 5% of water and 0.1% of defoaming agent, then dispersing at the rotating speed of 1000rpm for 10min, and defoaming at the low speed of 100rpm for 30min to obtain the water-based heavy anti-corrosion coating, wherein the viscosity of the obtained water-based heavy anti-corrosion coating is 49s (coating a 4# cup at 25 ℃); solid content: 62.7% (color: gray, measured as the solid content in the weight ratio of the total paint after baking at 120 ℃ for 2 h).

Example 2:

the water-based heavy-duty anticorrosive paint comprises the following components in percentage by weight: 40% of water-based novolac epoxy resin, 0.5% of anti-flash rust agent, 15% of rust-proof pigment (8% of zinc phosphomolybdate, 6% of zinc phosphate and 1% of aluminum tripolyphosphate), 5% of titanium dioxide (DuPont 902), 10% of barium sulfate (precipitated barium sulfate), 5% of mica powder (mesh number 1250), 5% of talcum powder (mesh number 1250), 3% of BYK190 dispersant, 1.0% of BYK346 wetting agent, 0.5% of flatting agent II (BYK381), 5% of organic solvent (ethylene glycol butyl ether 2%, 3% of propylene glycol methyl ether), 1.0% of heat stabilizer, 0.5% of colorant (water-based carbon black slurry), 0.5% of defoaming agent (BYK021), 0.2% of hydroxy cellulose thickener and 7.8% of water; the water-based novolac epoxy resin is F-51, the solid content is more than or equal to 55 percent, and the epoxy equivalent is 250-1000 g/eq.

(1) according to the weight percentage, 40% of water-based novolac epoxy resin, 5% of water and 3% of dispersing agent are sequentially added, after the materials are dispersed for 5min at the rotating speed of 800rpm, the dispersing speed is adjusted to 2000rpm, 5% of titanium dioxide, 10% of barium sulfate, 5% of mica powder, 5% of talcum powder and 15% of antirust pigment are sequentially added, finally, 0.5% of water-based carbon black slurry and 0.3% of defoaming agent are added, after the materials are dispersed at the rotating speed of 2000rpm for 20min, original slurry is obtained, the original slurry is transferred to a grinding cylinder, 3.5 times of weight of zirconia beads are added into the slurry under the cooling of circulating cooling water, the materials are ground for 200min at the rotating speed of 2000rpm, and the zirconia beads are filtered, so that slurry I is obtained, and the fineness is less than or equal to 15 mu m.

(2) While dispersing at the rotating speed of 800rpm, sequentially adding 1.0% of wetting agent, 5% of organic solvent, 1.0% of heat stabilizer, 0.5% of flatting agent II, 0.2% of thickening agent and 0.5% of flash rust inhibitor into the slurry I prepared in the step (1), after dispersing for 10min, sequentially adding 2.8% of water and 0.2% of defoaming agent, then dispersing for 10min at the rotating speed of 400rpm, and defoaming for 10min at the low speed of 300rpm to obtain the water-based heavy-duty anticorrosive coating, wherein the viscosity of the obtained water-based heavy-duty anticorrosive coating is 52s (coating a 4# cup at 25 ℃); solid content: 65.5% ((test solids content to total coating weight ratio after baking at 120 ℃ for 2 h); color: gray).

Example 3

The water-based heavy-duty anticorrosive paint comprises the following components in percentage by weight: 30% of water-based novolac epoxy resin, 1.0% of anti-flash rust agent, 10% of anti-rust pigment (zinc bismuthate phosphate 2% and zinc phosphate 8%), 10% of titanium dioxide (DONKA 2377), 16% of barium sulfate (precipitated barium sulfate), 5% of mica powder (mesh number 1250), 5% of calcium carbonate (mesh number 1250), 4% of dispersing agent (TEGO disper 560), 0.7% of wetting agent (German Baschiff EFKA3772), 0.3% of flatting agent I (BYK 333), 0.3% of flatting agent II (BYK381), 8% of organic solvent (isopropanol 1%, ethanol 3%, propylene glycol methyl ether 3%, dipropylene glycol methyl ether 1%), 0.5% of heat stabilizer, 1% of colorant (water-based carbon black slurry), 0.5% of defoaming agent (SF561), 0.3% of inorganic bentonite thickener and 7.4% of water; the water-based novolac epoxy resin is F-51, the solid content is more than or equal to 55 percent, and the epoxy equivalent is 250-1000 g/eq.

(1) according to the weight percentage, 30% of water-based novolac epoxy resin, 6% of water and 4% of dispersing agent are sequentially added, after the materials are dispersed for 10min at the rotating speed of 600rpm, the dispersing speed is adjusted to 600rpm, 10% of titanium dioxide, 16% of barium sulfate, 5% of mica powder, 5% of calcium carbonate and 10% of antirust pigment are sequentially added, finally, 1.0% of water-based carbon black slurry and 0.3% of defoaming agent are added, after the materials are dispersed at the rotating speed of 1000rpm for 40min, original slurry is obtained, the original slurry is transferred to a grinding cylinder, 2.5 times of weight of zirconia beads are added into the slurry under the cooling of circulating cooling water, the materials are ground for 80min at the rotating speed of 3000rpm, and the zirconia beads are filtered, so that slurry I is obtained, and the fineness is less than or equal to 15 mu m.

While dispersing at the rotating speed of 800rpm, sequentially adding 0.7% of wetting agent, 8% of organic solvent, 0.5% of heat stabilizer, 0.3% of flatting agent I, 0.3% of flatting agent II, 0.3% of thickening agent, 1.0% of flash rust inhibitor into the slurry I prepared in the step (1), dispersing for 20min, sequentially adding 1.4% of water and 0.2% of defoaming agent, dispersing for 15min at the rotating speed of 800rpm, defoaming at the low speed of 200rpm for 20min to obtain the water-based heavy anti-corrosion coating, wherein the viscosity of the obtained water-based heavy anti-corrosion coating is as follows: 58s (in # 4 cup, 25 ℃); solid content: 67.3% (test solids content to total coating weight ratio after baking at 120 ℃ for 2 h); color: and grey.

Example 4

The water-based heavy-duty anticorrosive paint comprises the following components in percentage by weight: 20% of water-based novolac epoxy resin (solid content: 55%, F-51), 2% of anti-flash rust agent, 5% of anti-rust pigment (aluminum tripolyphosphate 2% and strontium phosphate zinc 3%), 5% of titanium dioxide (python 996), 10% of barium sulfate (natural barium sulfate, the mesh number is 4000 meshes), 10% of mica powder (the mesh number is 2000 meshes), 2% of talcum powder (the mesh number is 2000 meshes), 2% of calcium carbonate (the mesh number is 2000 meshes), 6% of dispersing agent (BYK-2012), 0.5% of wetting agent (TEGO 270), 0.5% of flatting agent I (TEGO4000), 30% of organic solvent (propylene glycol methyl ether 10%, 20% of dipropylene glycol methyl ether), 0.2% of heat stabilizer, 1.0% of colorant (water-based blue paste), 0.3% of defoaming agent (SN-NXZ), 0.5% of inorganic bentonite thickener and 5% of water; the water-based novolac epoxy resin is F-51, the solid content is more than or equal to 55 percent, and the epoxy equivalent is 250-1000 g/eq.

(1) sequentially adding 20% of water-based novolac epoxy resin, 3% of water and 6% of dispersing agent, dispersing for 8min at the rotating speed of 300rpm, adjusting the dispersing speed to 1000rpm, sequentially adding 5% of titanium dioxide, 10% of barium sulfate, 10% of mica powder, 2% of calcium carbonate, 2% of talcum powder and 5% of antirust pigment, finally adding 1% of water-based blue slurry and 0.2% of defoaming agent, dispersing at the rotating speed of 600rpm at a high speed for 60min to obtain original slurry, transferring the original slurry into a grinding cylinder, adding zirconium oxide beads with the weight 1.5 times that of the slurry under the cooling of circulating cooling water, grinding for 30min at the rotating speed of 5000rpm, and filtering the zirconium oxide beads to obtain slurry I with the fineness of less than or equal to 15 microns.

(2) And (2) while dispersing at the rotating speed of 500rpm, sequentially adding 0.5% of wetting agent, 30% of organic solvent, 0.2% of heat stabilizer, 0.5% of flatting agent I, 0.5% of thickening agent and 2% of flash rust inhibitor into the slurry I prepared in the step (1), after dispersing for 10min, sequentially adding 2% of water and 0.1% of defoaming agent, and after dispersing at the rotating speed of 1000rpm for 20min, defoaming at the low speed of 100rpm for 30min to obtain the water-based heavy-duty anticorrosive coating.

Example 5

The water-based heavy-duty anticorrosive paint comprises the following components in percentage by weight: 20% of water-based novolac epoxy resin (solid content: 55%, F-51), 2% of anti-flash rust agent, 15% of anti-rust pigment (aluminum tripolyphosphate 8% and strontium phosphate zinc 7%), 15% of titanium dioxide (python 996), 20% of barium sulfate (natural barium sulfate, mesh number: 4000), 5% of mica powder (mesh number: 2000), 2% of talcum powder (mesh number: 2000), 2% of calcium carbonate (mesh number: 2000), 6% of dispersing agent (BYK-2012), 0.5% of wetting agent (TEGO 270), 0.5% of flatting agent I (TEGO4000), 5% of organic solvent (propylene glycol methyl ether 3%, dipropylene glycol methyl ether 2%), 0.2% of heat stabilizer, 1.0% of colorant (water-based blue slurry), 0.3% of defoaming agent (SN-NXZ), 0.5% of inorganic bentonite thickener and 5% of water; the water-based novolac epoxy resin is F-51, the solid content is more than or equal to 55 percent, and the epoxy equivalent is 250-1000 g/eq.

(1) sequentially adding 20% of water-based novolac epoxy resin, 3% of water and 6% of dispersing agent, dispersing for 8min at the rotating speed of 300rpm, adjusting the dispersing speed to 1000rpm, sequentially adding 15% of titanium dioxide, 20% of barium sulfate, 5% of mica powder, 2% of calcium carbonate, 2% of talcum powder and 15% of antirust pigment, finally adding 1% of water-based blue slurry and 0.2% of defoaming agent, dispersing at the rotating speed of 600rpm at a high speed for 60min to obtain original slurry, transferring the original slurry into a grinding cylinder, adding zirconium oxide beads with the weight 1.5 times that of the slurry under the cooling of circulating cooling water, grinding for 30min at the rotating speed of 5000rpm, and filtering the zirconium oxide beads to obtain slurry I with the fineness of less than or equal to 15 microns.

(2) And (2) while dispersing at the rotating speed of 500rpm, sequentially adding 0.5% of wetting agent, 5% of organic solvent, 0.2% of heat stabilizer, 0.5% of flatting agent I, 0.5% of thickening agent and 2% of flash rust inhibitor into the slurry I prepared in the step (1), after dispersing for 10min, sequentially adding 2% of water and 0.1% of defoaming agent, and after dispersing at the rotating speed of 1000rpm for 20min, defoaming at the low speed of 100rpm for 30min to obtain the water-based heavy-duty anticorrosive coating.

Comparative example 1

The water-based anticorrosive paint comprises the following components in percentage by weight: 40% of water-based conventional epoxy resin (co-curing chemical 2056 epoxy emulsion), 0.5% of anti-flash rust agent, 15% of rust-proof pigment (8% of zinc phosphomolybdate, 6% of zinc phosphate and 1% of aluminum tripolyphosphate), 5% of titanium dioxide (DuPont 902), 10% of barium sulfate (precipitated barium sulfate), 5% of mica powder (1250 meshes), 5% of talcum powder (1250 meshes), 3% of BYK190 dispersant, 1.0% of BYK346 wetting agent, 0.5% of flatting agent II (BYK381), 5% of organic solvent (ethylene glycol butyl ether 2%, 3% of propylene glycol methyl ether), 1.0% of heat stabilizer, 0.5% of colorant water-based carbon black slurry, 0.5% of defoaming agent (BYK021), 0.2% of hydroxy cellulose thickener and 7.8% of water;

The preparation method of the water-based anticorrosive paint comprises the following steps:

(1) according to the weight percentage, 40% of aqueous conventional epoxy resin (co-curing chemical 2056 epoxy emulsion), 5% of water and 3% of dispersing agent are sequentially added, after the mixture is dispersed for 5min at the rotating speed of 800rpm, the dispersing speed is adjusted to 2000rpm, 5% of titanium dioxide, 10% of barium sulfate, 5% of mica powder, 5% of talcum powder and 15% of antirust pigment are sequentially added, finally 0.5% of aqueous carbon black slurry and 0.3% of defoaming agent are added, after the mixture is dispersed at the rotating speed of 2000rpm for 20min, the original slurry is obtained, the original slurry is transferred to a grinding cylinder, under the cooling of circulating cooling water, 3.5 times of zirconia beads by weight of the slurry are added, the mixture is ground for 200min at the rotating speed of 2000rpm, and the zirconia beads are filtered, so that the slurry I is obtained, and the fineness is less than or equal to 15 mu m.

(2) And (2) while dispersing at the rotating speed of 800rpm, sequentially adding 1.0% of wetting agent, 5% of organic solvent, 1.0% of heat stabilizer, 0.5% of flatting agent II, 0.2% of thickening agent and 0.5% of flash rust inhibitor into the slurry I prepared in the step (1), after dispersing for 10min, sequentially adding 2.8% of water and 0.2% of defoaming agent, then dispersing at the rotating speed of 400rpm for 10min, and defoaming at the low speed of 300rpm for 10min to obtain the water-based anticorrosive coating.

Comparative example 2

The water-based anticorrosive paint comprises the following components in percentage by weight: 30% of water-based novolac epoxy resin, 1.0% of anti-flash rust agent, 10% of anti-rust pigment (zinc bismuthate phosphate 2% and zinc phosphate 8%), 10% of titanium dioxide (DONKA 2377), 16% of barium sulfate (precipitated barium sulfate), 5% of mica powder (mesh number 1250), 5% of calcium carbonate (mesh number 1250), 4% of dispersing agent (TEGO disper 560), 0.7% of wetting agent (EFKA3772), 0.3% of flatting agent I (BYK 333), 0.3% of flatting agent II (BYK381), 8% of organic solvent (isopropanol 1%, ethanol 3%, propylene glycol methyl ether 3%, 1% of dipropylene glycol methyl ether), 1% of coloring agent (water-based carbon black slurry), 0.5% of defoaming agent (SF561), 0.3% of inorganic bentonite thickening agent and 7.9% of water; the water-based novolac epoxy resin is F-51, the solid content is more than or equal to 55 percent, and the epoxy equivalent is 250-1000 g/eq.

(1) according to the weight percentage, 30% of water-based novolac epoxy resin, 6.5% of water and 4% of dispersing agent are sequentially added, after the materials are dispersed for 10min at the rotating speed of 600rpm, the dispersing speed is adjusted to 600rpm, 10% of titanium dioxide, 16% of barium sulfate, 5% of mica powder, 5% of calcium carbonate and 10% of antirust pigment are sequentially added, finally 1.0% of water-based carbon black slurry and 0.3% of defoaming agent are added, after the materials are dispersed at the rotating speed of 1000rpm for 40min, original slurry is obtained, the original slurry is transferred to a grinding cylinder, 2.5 times of weight of zirconia beads are added into the slurry under the cooling of circulating cooling water, the mixture is ground for 80min at the rotating speed of 3000rpm, and the zirconia beads are filtered to obtain slurry I, wherein the fineness is less than or equal to 15 microns.

And (2) while dispersing at the rotating speed of 800rpm, sequentially adding 0.7% of wetting agent, 8% of organic solvent, 0.3% of flatting agent I, 0.3% of flatting agent II, 0.3% of thickening agent, 1.0% of flash rust inhibitor into the slurry I prepared in the step (1), dispersing for 20min, sequentially adding 1.4% of water and 0.2% of defoaming agent, dispersing for 15min at the rotating speed of 800rpm, defoaming for 20min at the low speed of 200rpm, and thus obtaining the water-based anticorrosive paint.

Comparative example 3

The water-based anticorrosive paint comprises the following components in percentage by weight: 40% of water-based novolac epoxy resin, 0.5% of anti-flash rust agent, 16% of anti-rust pigment (8% of zinc phosphate and 8% of aluminum tripolyphosphate), 5% of titanium dioxide (DuPont 902), 10% of barium sulfate (precipitated barium sulfate), 5% of mica powder (mesh number is 1250 mesh), 5% of talcum powder (mesh number is 1250 mesh), 3% of BYK190 dispersant, 1.0% of BYK346 wetting agent, 0.5% of flatting agent II (BYK381), 5% of organic solvent (ethylene glycol butyl ether 2%, 3% of propylene glycol methyl ether), 1.0% of heat stabilizer, 0.5% of colorant water-based carbon black slurry, 0.5% of defoaming agent (BYK021), 0.2% of hydroxy cellulose thickener and 6.8% of water; the water-based novolac epoxy resin is F-51, the solid content is more than or equal to 55 percent, and the epoxy equivalent is 250-1000 g/eq.

(1) according to the weight percentage, 40% of water-based novolac epoxy resin, 5% of water and 3% of dispersing agent are sequentially added, after the materials are dispersed for 5min at the rotating speed of 800rpm, the dispersing speed is adjusted to 2000rpm, 5% of titanium dioxide, 10% of barium sulfate, 5% of mica powder, 5% of talcum powder and 16% of antirust pigment are sequentially added, finally, 0.5% of water-based carbon black slurry and 0.3% of defoaming agent are added, after the materials are dispersed at the rotating speed of 2000rpm for 20min, original slurry is obtained, the original slurry is transferred to a grinding cylinder, 3.5 times of weight of zirconia beads are added into the slurry under the cooling of circulating cooling water, the materials are ground for 200min at the rotating speed of 2000rpm, and the zirconia beads are filtered, so that slurry I is obtained, and the fineness is less than or equal to 15 mu m.

(2) And (2) while dispersing at the rotating speed of 800rpm, sequentially adding 1.0% of wetting agent, 5% of organic solvent, 1.0% of heat stabilizer, 0.5% of flatting agent I, 0.2% of thickening agent and 0.5% of flash rust inhibitor into the slurry I prepared in the step (1), after dispersing for 10min, sequentially adding 1.8% of water and 0.2% of defoaming agent, then dispersing for 10min at the rotating speed of 400rpm, and defoaming for 10min at the low speed of 300rpm to obtain the water-based anticorrosive coating.

Test example:

the anticorrosive coatings prepared in examples 1-3 and comparative examples 1-3 are mixed with a curing agent and deionized water and then sprayed; water-based anticorrosive paint: curing agent: deionized water 3: 1: wherein the curing agent is an amine curing agent specifically formulated with the base paint (i.e., the aqueous heavy duty coating of the example or the aqueous anti-corrosive coating of the comparative example) for the reaction of epoxy groups in the base paint. Cardanol modified amine curing agent was used in example 1, and modified alicyclic amine was used in example 2; example 3 used was an aromatic amine; comparative examples 1 and 3 use modified cyclic amines and comparative example 2 uses aromatic amines, as follows for the aqueous anticorrosive coatings: curing agent: deionized water 3: 1: 1, uniformly stirring; humidity at a temperature of 23 ± 2 ℃: 30-60%, using a spray gun with the diameter of 2.0mm to keep the air spraying pressure at 4-6 kg, spraying the air spraying pressure on a cold rolled steel plate with the diameter of 7cm x 13cm (the steel plate needs to be cleaned by wiping with alcohol after being polished), and spraying the construction dry film with the thickness of less than or equal to 60 mu m at one time; naturally drying, and performing secondary coating after 24 hours; after the secondary spraying reaches the dry film of 150 mu m, the product can be naturally placed for 3 days in the environment with the temperature of 23 +/-2 ℃ and the humidity of 55 percent, the adhesive force of the product can be detected, and after 15 days, the temperature resistance and the salt spray test can be carried out.

And (3) testing the adhesive force:

according to the test, after the steel plate to be tested is subjected to lattice division according to the standard GB/T9286, the steel plate to be tested is suddenly stripped by using a bonded adhesive tape, and the coating condition at the lattice division position is observed.

And (3) temperature resistance and salt spray resistance test:

and performing temperature resistance test according to GB/T1735-2009, placing the steel plate to be tested in an environment with the temperature of 23 +/-2 ℃ and the humidity of 55% for 15 days, placing the steel plate in a muffle furnace, and performing temperature resistance test by setting parameters at 210 ℃ for 72 h.

The salt spray resistance is carried out according to GB/T10125-2012, and the steel plate to be tested is placed in a salt spray box at 35 +/-2 ℃ after being placed in an environment with the temperature of 23 +/-2 ℃ and the humidity of 55% for 15 days, and the salt spray resistance is measured. Wherein, in the salt fog tank, the concentration of NaCl is 50g +/-2 g/L; the pH value of the solution is 6.5-7.2; the spraying amount is less than 80cm²The area is 1.0-2.0ml/80cm²·h。

The test results of adhesion, temperature resistance and salt spray resistance are shown in table 1.

TABLE 1

As can be seen from Table 1, the adhesion of the steel plates sprayed with the coatings prepared in examples 1 to 3 can reach 0 to 1 grade; no crack is generated through a temperature resistance test of 210 ℃ for 72h, and the surface gloss is good; the 720-hour salt spray resistance test is directly carried out, the salt spray resistance performance is good, the coating does not have corrosion and bubbles, the temperature resistance is carried out at 210 ℃ for 72 hours, then the salt spray resistance is carried out for 360 hours, the surface of the coating is good, and the corrosion and the bubbles do not occur. Compared with the examples 1-3, the steel plate sprayed by the coating prepared by the comparative examples 1-3 has poor coating adhesion, and the coating prepared by the comparative examples can be stuck off by the diameter adhesive tape without passing a hundred-grid test; the coating shows light loss in comparison before and after temperature resistance. The film thickness of the coating of the comparative example 1 is reduced by 50%, and after the temperature resistance test of the coating of the comparative example 1, the adhesive tape can directly and completely stick off the coating without hundreds of cases, so that the salt fog after temperature resistance can be expected to meet the most rigorous temperature resistance requirement of the transformer core. The steel plate sprayed with the paint prepared in comparative example 2 was cracked and tarnished after a temperature resistance test, but the film thickness of the coating was not changed. The steel plate sprayed with the coating prepared in the comparative example 3 has cracks and a dull surface after a temperature resistance test, directly resists salt spray for 480h, generates bubbles on the surface of a coating film, and generates bubbles after the temperature resistance test is carried out for 240 h.

Three identical steel plates, 1 cross, and two non-cross, were sprayed with the coating prepared in example 1, and a comparative experiment was conducted with direct salt spray of 720h and temperature of 210 ℃ 72h followed by 360h salt spray. According to experiments, the three test samples of 720h direct salt spray without temperature resistance test are found, the thicknesses of the plates without cross are respectively 121 micrometers and 203 micrometers, the coating does not have the bad phenomena of foaming corrosion and the like, the plates are cross tested, the thickness of the film is 158 micrometers, and the single-side corrosion width of the cross part is 1.7 mm. After the steel plate is subjected to temperature resistance of 210 ℃ for 72h, the steel plate is subjected to a 360h salt spray test, the thicknesses of two plates without scratching are 162 micrometers and 214 micrometers respectively, the phenomena of surface bubbling and corrosion do not occur, the steel plate is scratched to form a test plate, the thickness of the steel plate is 172 micrometers, and the unilateral corrosion width of the salt spray is 1.4 mm. It is shown that the coating of example 1 fully meets the most stringent temperature and salt spray corrosion resistance test requirements for iron cores.

In addition, a comparative experiment of salt spray 360h after direct salt spray 720h and temperature resistance test of 210 ℃ 72h by spraying 3 steel plates, 1 piece of cross and two pieces of non-cross with the coating prepared in example 2 shows that the thickness of the non-cross plate is 108 μm and 127 μm respectively, the coating has no bad phenomena such as bubbling corrosion, etc., the thickness of the cross test plate is 178 μm, and the single-side corrosion width of the cross part is 1.9 mm. After the temperature is increased to 210 ℃ for 72h, the test is carried out for 360h by salt spray, the thicknesses of two plates without cross are 132 micrometers and 134 micrometers respectively, the phenomena of surface bubbling and corrosion do not occur, the test plates are crossed, the thickness of the film is 159 micrometers, and the unilateral corrosion width of the salt spray is 1.7 mm. The coating prepared in example 2 completely meets the most severe temperature resistance and salt spray corrosion resistance test requirements of the iron core after being sprayed.

A contrast experiment of spraying 3 steel plates, 1 scribed plate and two undivided plates with the coating prepared in the example 2 on the salt spray after direct salt spray 720h and temperature resistance of 210 ℃ 72h shows that in a test sample plate without direct salt spray 720h, the thicknesses of the undivided plates are 111 micrometers and 173 micrometers respectively, the coating has no bad phenomena such as foaming corrosion and the like, the thickness of the test plate for scribing is 148 micrometers, and the single-edge corrosion width of the scribed part is not 1.5 mm. And after the temperature is 210 ℃ for 72h, the test is carried out for 360h by a salt spray test, the thicknesses of two plates without cross are respectively 122 micrometers and 234 micrometers, the phenomena of surface foaming and corrosion do not occur, the test plates are crossed, the thickness of the films is 165 micrometers, and the unilateral corrosion width of the salt spray is 1.5 mm. The most stringent temperature and salt spray corrosion resistance test requirements for the fully clad core of example 3 are illustrated.

As shown in figure 2 before and after the temperature resistance test of the steel plate sprayed by the coating prepared in the comparative example 2, the comparison of pictures shows that the coating is obviously cracked after the heat resistance is realized without adding a heat stabilizer, and the film thickness of the coating is reduced by 30% before and after the heat resistance is realized. The temperature resistance can not meet the most harsh temperature resistance requirement of the iron core, and the salt spray test can not be carried out after the temperature resistance.

After the paint prepared in the comparative example 3 is sprayed, a salt spray resistance test is carried out, and the result is shown in fig. 3, and it can be seen from a salt spray comparison picture that when the conventional zinc phosphate and aluminum tripolyphosphate are selected as the antirust pigment in the formula, the salt spray performance before and after temperature resistance is greatly reduced, wherein the salt spray foams 480h before temperature resistance, and the salt spray foams 240h after temperature resistance of 210 ℃ 72 h. That is to say, the formula can meet the harsh temperature-resistant requirement of the iron core, but can not meet the most harsh salt mist corrosion-resistant requirement of the iron core.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that it is obvious to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and these modifications and improvements should also be considered as the protection scope of the present invention.

Claims

1. The water-based heavy-duty anticorrosive paint is characterized by comprising the following components in percentage by weight: 20-40% of water-based phenolic epoxy resin, 0.5-2% of anti-flash rust agent, 5-15% of anti-rust pigment, 5-15% of titanium dioxide, 10-20% of barium sulfate, 5-15% of mica powder, 0-5% of talcum powder, 0-5% of calcium carbonate, 3-6% of dispersing agent, 0.5-1.0% of wetting agent, 0-0.5% of flatting agent I, 0-0.5% of flatting agent II, 3-30% of organic solvent, 0.2-1.0% of heat stabilizer, 0.1-1% of colorant, 0.2-0.5% of defoaming agent, 0.2-0.5% of thickening agent and 5-20% of water;

2. The water-based heavy-duty anticorrosive coating according to claim 1, wherein the rust-preventive pigment is at least two of zinc phosphate, zinc bismuthate, zinc phosphomolybdate, aluminum tripolyphosphate, zinc strontiate, and zinc silicate.

3. The aqueous heavy duty anticorrosive coating of claim 1, wherein said titanium dioxide is one or more of dupont 706, dupont 902, tojia 2377, and python 996.

4. The water-based heavy-duty anticorrosive coating according to claim 1, wherein the barium sulfate is one or both of precipitated barium sulfate and natural barium sulfate; the mesh number of the natural barium sulfate is 1250-4000 meshes; the mesh number of the mica powder is 1250-4000 meshes; the mesh number of the talcum powder is 1250-4000 meshes; the mesh number of the calcium carbonate is 1250-4000 meshes; the dispersant is a block polymer dispersant.

5. The water-based heavy-duty anticorrosive paint according to claim 1, wherein the wetting agent is one or more of a polyether-modified organosilicon wetting agent and a fluorine-modified organosilicon wetting agent, and the leveling agent I is a polyether-modified organosilicon leveling agent; and the leveling agent II is an acrylic leveling agent.

6. The water-based heavy-duty anticorrosive coating according to claim 1, wherein the organic solvent is one or more of ether and alcohol; the ether is at least two of propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, propylene glycol butyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, diethylene glycol methyl ether, diethylene glycol butyl ether, diethylene glycol propyl ether and diethylene glycol ethyl ether; the alcohol is at least two of ethanol, isopropanol and n-butanol; the mass fraction of ether in the organic solvent is 66.7-100%, and the mass fraction of alcohol is 0-33.3%; the colorant is one or more of water-based carbon black pulp, water-based blue pulp, water-based iron yellow pulp, water-based iron red pulp, water-based green pulp, water-based purple pulp and water-based bright red pulp; the defoaming agent is one or more of silicone defoaming agent, mineral oil defoaming agent and acetylene glycol defoaming agent; the thickening agent is one or more of inorganic bentonite and hydroxy cellulose.

7. A preparation method of the water-based heavy-duty anticorrosive coating as claimed in any one of claims 1 to 6, characterized by comprising the following steps:

8. The method according to claim 7, wherein in the step (1), the first dispersing speed is 300-800 rpm and the time is 5-10 min; the grinding is to place the original slurry in a grinding cylinder, add zirconia beads with the weight 1.5-3.5 times of that of the original slurry under the cooling of circulating cooling water, and grind for 30-200 min at the rotating speed of 2000-5000 rpm; the fineness of the slurry I is less than or equal to 15 mu m.

9. The method according to claim 7, wherein in the step (2), the re-dispersing speed is 400 to 1000rpm and the time is 10 to 20 min; the defoaming speed is 100-300 rpm, and the defoaming time is 10-30 min.

10. Use of the aqueous heavy duty coating according to any one of claims 1 to 6 for transformer cores.