CN113801536A - Antirust coating for electric appliance rack and preparation method thereof - Google Patents

Abstract

The invention relates to an antirust coating for an electric appliance rack and a preparation method thereof, belonging to the technical field of coating. The coating comprises the following raw materials in percentage by weight: epoxy resin powder, modified polyester powder, a leveling agent, a brightener, benzoin, wax powder, precipitated barium, a brightener, carbon black and titanium dioxide; the preparation method comprises the steps of treating precipitated barium, carbon black and titanium dioxide by using a coupling agent to improve the compatibility of an inorganic filler, and mixing the raw materials to prepare the coating, wherein the modified polyester is blended by using PET and PBT and has good comprehensive performance, tannic acid and pyromucic acid are added in a compounding manner, the tannic acid has a conversion effect on surface layer rust, the pyromucic acid has good permeability and can be subjected to deep conversion, and meanwhile, a pyromucic acid conversion product fills gaps in a tannic acid conversion film, so that the compactness of the conversion film is excellent, and the antirust performance is jointly improved by means of rust conversion and formation of a compact conversion film.

Description

Antirust coating for electric appliance rack and preparation method thereof

Technical Field

The invention belongs to the technical field of coating, and particularly relates to an antirust coating for an electric appliance rack and a preparation method thereof.

Background

The powder paint is a solid powder synthetic resin paint composed of solid resin, pigment, filler and assistant, and is different from ordinary solvent paint and water paint in that its dispersion medium is not solvent and water, but air, and it has the features of no solvent pollution, 100% filming and low energy consumption.

The electric appliance support is used for supporting an electric appliance, once the electric appliance is corroded, the use safety of the electric appliance is seriously influenced, the electric appliance is usually rustproof by adopting a coating mode, the basic mechanism of the corrosion of steel materials is that steel is in contact with air, and the steel is corroded and corroded by electrochemistry and chemical reaction in an environment containing moisture and oxygen, so that the corrosion is caused.

The invention provides an antirust coating suitable for coating an electric appliance bracket and a preparation method thereof according to years of production experience.

Disclosure of Invention

In order to solve the technical problems mentioned in the background technology, the invention provides an antirust coating for an electric appliance rack and a preparation method thereof

The purpose of the invention can be realized by the following technical scheme:

the antirust coating for the electric appliance rack comprises the following raw materials in percentage by weight:

20 to 32 percent of epoxy resin powder, 31 to 37 percent of modified polyester powder, 1.8 to 2.4 percent of flatting agent, 0.6 to 1.2 percent of brightener, 0.35 to 0.45 percent of benzoin, 0.35 to 0.45 percent of wax powder, 31.4 to 37.6 percent of precipitated barium, 0.35 to 0.65 percent of brightener, 0.65 to 0.95 percent of carbon black and 0.3 to 0.5 percent of titanium pigment;

the modified polyester powder is prepared by the following steps:

step A1: adding PET particles and PBT particles into a high-speed mixer, and crushing and mixing until the particle size of the particles is not more than 4mm to obtain a mixture;

step A2: adding the mixture into a heating tank, stirring and heating to 250 ℃ and 260 ℃, then preserving heat and stirring until the mixture is completely molten, adding tannic acid and pyro-pakconic acid, stirring for 3-5min, and then rapidly extruding into a cooling tank to be cooled into blocks to obtain modified polyester blocks;

step A3: crushing the modified polyester material blocks into small blocks by a crusher, and then grinding the small blocks into powder by a grinder to obtain modified polyester powder.

Further, in the step A1, the mass ratio of the PET particles to the PBT particles is 1: 1.25-1.4.

Further, in the step A2, the addition amount of tannic acid is 0.12 to 0.15 percent of the total mass of the PET particles and the PBT particles.

Further, in the step A2, the adding amount of the pyro-acid is 0.18-0.22% of the total mass of the PET particles and the PBT particles.

Further, the brightener is ethylene-maleic anhydride grafted copolymer wax C701.

Further, the energizer is prepared by mixing an electrizer EDI and an electrizer H318 according to the mass ratio of 1: 0.65.

Further, the leveling agent is a leveling agent L88.

A preparation method of an antirust coating for an electric appliance rack comprises the following steps:

step S1: mixing KH-550 silane coupling agent with ethanol solution under stirring, adding sodium hydroxide solution dropwise, and adjusting pH to 8-10 to obtain treated solution;

step S2: adding precipitated barium, carbon black and titanium dioxide into the treatment fluid, stirring and mixing to obtain a filling wet material, then flatly spreading the filling wet material into a drying disc, placing the drying disc into microwave drying equipment, drying the filling wet material to constant weight, and then crushing and dispersing the dried filling wet material by adopting a crusher to obtain a filler;

step S3: and adding epoxy resin powder, modified polyester powder, a leveling agent, a brightener, benzoin, wax powder, a brightener and a filler into a high-speed mixer for mixing to obtain the antirust coating for the electric appliance rack.

Further, in step S1, the volume concentration of the ethanol solution is 20%, the volume ratio of the KH-550 silane coupling agent to the ethanol solution is 1:3.7-4.3, and the mass fraction of the sodium hydroxide solution is 10%.

Further, in step S2, the usage ratio of the treating fluid to the total mass of the precipitated barium, the carbon black and the titanium dioxide is 1L: 1.3-1.7 kg.

Further, in step S3, the batch materials are sieved with a 100-mesh sieve before being mixed.

The invention has the beneficial effects that:

1. the invention discloses a modified polyester and a modification method thereof in the process of preparing antirust paint, wherein the modified polyester adopts PET and PBT for blending, the modified polyester makes up for deficiencies of each other and has good comprehensive performance, simultaneously adopts tannic acid and pyro-octanic acid for compounding and adding, the tannic acid has a conversion effect on rust, the tannic acid has a poorer permeation effect due to larger molecular weight of the tannic acid, although a surface rust layer can be converted, the deep conversion is incomplete, the pyro-octanic acid is adopted for compounding and has good permeability, the deep conversion can be carried out, and gaps in a tannic acid conversion film can be filled after the pyro-octanic acid is converted into the rust, so that the conversion film has excellent compactness, a base material is further isolated from the outside, and the antirust performance is improved in a way of converting the rust and forming the compact conversion film.

2. The invention discloses a specific formula and a preparation method of an antirust coating, and the coating is coated by using the coating, so that the coating is uniform in color and luster, free of bubbles and orange peel, uniform in thickness, high in pencil hardness of 2H, high in bonding strength of 14.95-16.21MPa, excellent in adhesiveness, excellent in performance in 72H of neutral salt spray and good in antirust performance.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the implementation:

the brightener is ethylene-maleic anhydride grafted copolymer wax C701;

the energizer is prepared by mixing an electrizer EDI and an electrizer H318 according to the mass ratio of 1: 0.65;

the leveling agent is leveling agent L88.

Example 1

The modified polyester powder is prepared by the following specific preparation process:

step A1: adding PET particles and PBT particles into a high-speed mixer according to the mass ratio of 1:1.25, starting the equipment for mixing and crushing, detecting the particle size once every 2min, detecting the particle size to be 4mm in 12min of crushing, and stopping stirring and crushing to obtain a mixture;

step A2: adding the mixture into a heating tank, stirring and heating to 250 ℃, keeping the temperature for 15min, when the mixture is in a complete molten state, adding tannic acid accounting for 0.12 percent of the total mass of PET particles and PBT particles and pyro-pakcic acid accounting for 0.18 percent of the total mass of the PET particles and the PBT particles, increasing the rotating speed to 240r/min, stirring for 8min, extruding the mixture into a self-made cooling tank provided with a cooler through a screw extruder, and completely solidifying the mixture to obtain a modified polyester block;

step A3: crushing the modified polyester material blocks into small blocks by a crusher, and then grinding the small blocks into powder by a grinder to obtain modified polyester powder.

Example 2

The modified polyester powder is prepared by the following specific preparation process:

step A1: adding PET particles and PBT particles into a high-speed mixer according to the mass ratio of 1:1.3, starting the equipment for mixing and crushing, detecting the particle size every 2min, detecting the particle size to be 3.4mm in 14min of crushing, and stopping stirring to obtain a mixture;

step A2: adding the mixture into a heating tank, stirring and heating to 255 ℃, keeping the temperature for 15min, when the mixture is completely molten, adding tannic acid accounting for 0.14 percent of the total mass of PET particles and PBT particles and pyro-pakcic acid accounting for 0.2 percent of the total mass of the PET particles and the PBT particles, increasing the rotating speed to 270r/min, stirring for 6min, extruding the mixture into a self-made cooling tank provided with a cooler through a screw extruder, and completely solidifying the mixture to obtain a modified polyester block;

step A3: crushing the modified polyester material blocks into small blocks by a crusher, and then grinding the small blocks into powder by a grinder to obtain modified polyester powder.

Example 3

The modified polyester powder is prepared by the following specific preparation process:

step A1: taking PET particles and PBT particles according to a mass ratio of 1: 1.4 adding the mixture into a high-speed mixer, starting equipment for mixing and crushing, detecting the granularity once every 2min, detecting the granularity to be 3.2mm in 16min of crushing, and stopping stirring to obtain a mixture;

step A2: adding the mixture into a heating tank, stirring and heating to 260 ℃, keeping the temperature for 12min, adding tannic acid accounting for 0.15% of the total mass of PET particles and PBT particles and pyro-octanic acid accounting for 0.22% of the total mass of the PET particles and PBT particles into the mixture in a completely molten state, increasing the rotating speed to 300r/min, stirring for 5min, extruding the mixture into a self-made cooling tank provided with a cooler through a screw extruder, and completely solidifying the mixture to obtain a modified polyester block;

step A3: crushing the modified polyester material blocks into small blocks by a crusher, and then grinding the small blocks into powder by a grinder to obtain modified polyester powder.

Example 4

The antirust coating for the electric appliance rack is prepared by the embodiment, and comprises the following raw materials in percentage by weight:

20% of epoxy resin powder, 37% of modified polyester powder prepared in example 1, 1.8% of leveling agent, 1.2% of brightener, 0.35% of benzoin, 0.45% of wax powder, 37.6% of precipitated barium, 0.35% of electrical conduction agent, 0.95% of carbon black and 0.3% of titanium dioxide;

the preparation process comprises the following steps:

step S1: respectively taking a KH-550 silane coupling agent and an ethanol solution with the volume concentration of 20%, stirring and mixing according to the volume ratio of the KH-550 silane coupling agent to the ethanol solution of 1:3.7, then dropwise adding a sodium hydroxide solution with the mass fraction of 10%, and adjusting the pH value of the mixed solution to 8 to obtain a treatment solution;

step S2: mixing the precipitated barium, the carbon black and the titanium dioxide according to the weight percentage, and then mixing the mixed powder with the treatment fluid according to the dosage ratio of 1.3 kg: 1L of the mixture is mixed, a stirrer is adopted, the stirring speed is set to be 300r/min, the mixture is stirred for 50min, the mixture is fully stirred and mixed to prepare filling wet materials, then the filling wet materials are flatly paved in a drying disk, then the filling wet materials are added into a microwave dryer, the drying is carried out to constant weight, and then the drying materials are crushed and dispersed by a crusher to obtain filler;

step S3: and (2) sieving epoxy resin powder, modified polyester powder, a leveling agent, a brightener, benzoin, wax powder, a brightener and filler respectively through a 100-mesh sieve, taking the sieved materials, adding the materials into a stirrer for mixing at a stirring speed of 500r/min, and stirring for 1h to obtain the antirust paint for the electric appliance rack.

Example 5

The antirust coating for the electric appliance rack is prepared by the embodiment, and comprises the following raw materials in percentage by weight:

23% of epoxy resin powder, 34% of modified polyester powder prepared in example 2, 2.1% of a leveling agent, 0.9% of a brightener, 0.4% of benzoin, 0.4% of wax powder, 37.5% of precipitated barium, 0.5% of an electrical conduction agent, 0.8% of carbon black and 0.4% of titanium dioxide;

the preparation process comprises the following steps:

step S1: respectively taking a KH-550 silane coupling agent and an ethanol solution with the volume concentration of 20%, stirring and mixing according to the volume ratio of the KH-550 silane coupling agent to the ethanol solution of 1:4.1, then dropwise adding a sodium hydroxide solution with the mass fraction of 10%, and adjusting the pH value of the mixed solution to 9 to obtain a treatment solution;

step S2: mixing the precipitated barium, the carbon black and the titanium dioxide according to the weight percentage, and then mixing the mixed powder and the treatment fluid according to the dosage ratio of 1.5 kg: 1L of the mixture is mixed, a stirrer is adopted, the stirring speed is set to be 300r/min, the mixture is stirred for 40min, the mixture is fully stirred and mixed to prepare filling wet materials, then the filling wet materials are flatly paved in a drying disk, then the filling wet materials are added into a microwave dryer, the drying is carried out to constant weight, and then the drying materials are crushed and dispersed by a crusher to obtain filler;

step S3: and (3) sieving epoxy resin powder, modified polyester powder, a leveling agent, a brightener, benzoin, wax powder, a brightener and filler respectively through a 100-mesh sieve, taking the sieved materials, adding the materials into a stirrer for mixing at a stirring speed of 600r/min, and stirring for 50min to obtain the antirust coating for the electric appliance rack.

Example 6

The antirust coating for the electric appliance rack is prepared by the embodiment, and comprises the following raw materials in percentage by weight:

32% of epoxy resin powder, 31% of modified polyester powder prepared in example 1, 2.4% of a leveling agent, 0.6% of a brightener, 0.45% of benzoin, 0.35% of wax powder, 31.4% of precipitated barium, 0.65% of an electrical conduction agent, 0.65% of carbon black and 0.5% of titanium dioxide;

the preparation process comprises the following steps:

step S1: respectively taking a KH-550 silane coupling agent and an ethanol solution with the volume concentration of 20%, stirring and mixing according to the volume ratio of the KH-550 silane coupling agent to the ethanol solution of 1:4.3, then dropwise adding a sodium hydroxide solution with the mass fraction of 10%, and adjusting the pH value of the mixed solution to 10 to obtain a treatment solution;

step S2: mixing the precipitated barium, the carbon black and the titanium dioxide according to the weight percentage, and then mixing the mixed powder with the treatment fluid according to the dosage ratio of 1.7 kg: 1L of the mixture is mixed, a stirrer is adopted, the stirring speed is set to be 300r/min, the mixture is stirred for 40min, the mixture is fully stirred and mixed to prepare filling wet materials, then the filling wet materials are flatly paved in a drying disk, then the filling wet materials are added into a microwave dryer, the drying is carried out to constant weight, and then the drying materials are crushed and dispersed by a crusher to obtain filler;

step S3: and (3) sieving epoxy resin powder, modified polyester powder, a leveling agent, a brightener, benzoin, wax powder, a brightener and a filler respectively through a 100-mesh sieve, taking the sieved materials, adding the materials into a stirrer for mixing at a stirring speed of 700r/min, and stirring for 40min to obtain the antirust paint for the electric appliance rack.

Taking 18Q 235 steel plates with the specification of 50mm x 50mm, carrying out ceramic treatment, wherein each 6 steel plates are 1 group, and carrying out electrostatic coating on each group by respectively adopting the coatings prepared in examples 4-6 according to the parameters in the table 1:

TABLE 1

Electrostatic voltage/kV	80
		Electrostatic current/. mu.A	100
Atomization pressure/MPa	0.09
		Curing temperature/. degree.C	240
Curing time/min	12

After coating, performing appearance evaluation on the coating, measuring the thickness of the coating by referring to GB/T1764-79 standard, performing pencil hardness test by referring to GB/T67394-1996 standard, performing bonding strength test by referring to GB/T5210-2006 standard, performing salt spray performance test by referring to GB/T23988-2009, wherein the related data are shown in Table 2:

TABLE 2

As can be seen from Table 2, after the coating prepared by the invention is coated, the coating is uniform in color and luster, free of bubbles and orange peel, uniform in thickness, 2H in pencil hardness, and excellent in adhesion, the bonding strength reaches 14.95-16.21MPa, and the coating is excellent in performance and has good antirust performance in 72H of neutral salt spray.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is illustrative and explanatory only and is not intended to be exhaustive or to limit the invention to the precise embodiments described, and various modifications, additions, and substitutions may be made by those skilled in the art without departing from the scope of the invention or exceeding the scope of the claims.

Claims (8)

1. The antirust coating for the electric appliance rack is characterized by comprising the following raw materials in percentage by weight:

20 to 32 percent of epoxy resin powder, 31 to 37 percent of modified polyester powder, 1.8 to 2.4 percent of flatting agent, 0.6 to 1.2 percent of brightener, 0.35 to 0.45 percent of benzoin, 0.35 to 0.45 percent of wax powder, 31.4 to 37.6 percent of precipitated barium, 0.35 to 0.65 percent of brightener, 0.65 to 0.95 percent of carbon black and 0.3 to 0.5 percent of titanium pigment;

the modified polyester powder is prepared by the following steps:

step A1: mixing and crushing PET particles and PBT particles until the particle size of the particles is not more than 4mm to obtain a mixture;

step A2: adding the mixture into a heating tank, stirring and heating to 250-260 ℃, then preserving heat and stirring until the mixture is completely molten, adding tannic acid and pyro-pakc, stirring for 3-5min, and then extruding into a cooling tank to be cooled into blocks to obtain modified polyester blocks;

step A3: crushing the modified polyester material blocks into small blocks by a crusher, and then grinding the small blocks into powder by a grinder to obtain modified polyester powder.

2. The antirust coating for the electric appliance rack as claimed in claim 1, wherein in the step A1, the dosage mass ratio of the PET particles to the PBT particles is 1: 1.25-1.4.

3. The antirust coating for the electric appliance rack as claimed in claim 1, wherein in the step A2, the addition amount of tannic acid is 0.12-0.15% of the mass of the mixture.

4. The antirust coating for the electric appliance rack as claimed in claim 1, wherein in the step A2, the addition amount of the pyro-boric acid is 0.18-0.22% of the mass of the mixture.

5. A preparation method of an antirust coating for an electric appliance rack is characterized by comprising the following steps:

step S1: mixing KH-550 silane coupling agent with ethanol solution under stirring, adding sodium hydroxide solution dropwise, and adjusting pH to 8-10 to obtain treated solution;

step S2: adding precipitated barium, carbon black and titanium dioxide into the treatment fluid, stirring and mixing to obtain a filling wet material, then drying the filling wet material by microwave to constant weight, and crushing and dispersing the dried filling wet material by adopting a crusher to obtain a filler;

step S3: and (3) stirring and mixing the filler and the other raw materials to obtain the antirust coating for the electric appliance rack.

6. The method for preparing the antirust coating for the electric appliance rack according to claim 5, wherein in step S1, the volume concentration of the ethanol solution is 20%, and the mass fraction of the sodium hydroxide solution is 10%.

7. The method for preparing the antirust coating for the electric appliance rack as claimed in claim 6, wherein the dosage volume ratio of the KH-550 silane coupling agent to the ethanol solution is 1: 3.7-4.3.

8. The method for preparing the antirust coating for the electric appliance rack according to claim 5, wherein in step S2, the dosage ratio of the treating fluid to the total mass of the precipitated barium, the carbon black and the titanium dioxide is 1L: 1.3-1.7 kg.