Coating with corrosion resistance and preparation method thereof

Abstract

The invention discloses a coating with corrosion resistance and a preparation method thereof, and the coating is prepared from the following raw materials in parts by weight: 35-55 parts of waterborne epoxy modified acrylic resin, 1-8 parts of modified nano boron carbide, 1-6 parts of fumed silica and 1-5 parts of nano bentonite. The water-based epoxy modified acrylic resin, the modified nano boron carbide, the fumed silica and the nano bentonite are added, and the water-based epoxy modified acrylic resin and the water-based epoxy ester resin are polymerized by the polydimethylsiloxane to obtain the polymer emulsion with good corrosion resistance, permeability and film-forming property. Meanwhile, hydroxyl in the silane coupling agent on the surface of the nano boron carbide fully reacts with active groups on the surface of the nano boron carbide, so that the nano boron carbide is highly uniformly dispersed in the water-based paint, agglomeration of the nano boron carbide in the paint is avoided, and the properties such as compactness, hardness and wear resistance are enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of anti-corrosion coatings, and in particular to a coating with anti-corrosion performance and a preparation method thereof. Background Art

[0002] In actual industrial production, many mechanical equipment need to work in harsh environments. Harsh environments such as acidic or alkaline liquids and gases have strong corrosive effects on mechanical equipment, which can seriously damage and fail the mechanical equipment. Once the mechanical equipment is damaged and fails, it may cause serious production accidents, causing losses to industrial production and personal safety.

[0003] In order to prevent mechanical equipment from failing due to corrosion, it is necessary to perform anti-corrosion treatment on the areas where the mechanical equipment is in contact with acidic or alkaline liquids and gases. Anti-corrosion technology has always been one of the important research contents in the field of coatings research at home and abroad. There are many ways to treat corrosion, and the most convenient way is to spray anti-corrosion coatings directly on the surface of mechanical equipment or engineering buildings. Anti-corrosion coating technology has developed rapidly in recent years and has become one of the main methods of anti-corrosion treatment.

[0004] Corrosion-resistant coatings are one of the important directions of the development of anti-corrosion coatings. They can effectively protect mechanical equipment from corrosion. In order to prevent acidic or alkaline liquids and gases from eroding anti-corrosion coatings, the anti-corrosion coatings used in these occasions are required to have corrosion resistance in addition to anti-corrosion. This kind of coating can cope with the erosion of multiple corrosive liquids or gases at the same time, and can provide better protection for mechanical equipment or pipelines.

[0005] In order to improve the corrosion resistance of anti-corrosion coatings, it is necessary to study the ratio combination of various different materials and develop new preparation methods. In order to enable mechanical equipment or pipelines working in harsh environments to work normally, it is urgent to develop a coating with anti-corrosion properties. Summary of the invention

[0006] In view of the defects of the prior art, the purpose of the present invention is to provide a coating with anti-corrosion performance and a preparation method thereof to solve the problems raised in the above background technology.

[0007] The present invention solves the technical problem by adopting the following technical solution:

[0008] The invention provides a coating with anticorrosive performance, which comprises the following raw materials by weight: 35-55 parts of waterborne epoxy modified acrylic resin, 1-8 parts of modified nano boron carbide, 1-6 parts of fumed silica and 1-5 parts of nano bentonite.

[0009] Preferably, the preparation method of the waterborne epoxy-modified acrylic resin comprises the following steps:

[0010] S1, polymerizing epoxy resin, methyl methacrylate, styrene, acrylic acid and initiator to obtain material A;

[0011] S2. Add polydimethylsiloxane to material A and water-based epoxy ester resin, mix and carry out polycondensation reaction to obtain water-based epoxy modified acrylic resin.

[0012] Preferably, in step S1, the mass ratio of epoxy resin, methyl methacrylate, styrene, acrylic acid and initiator is 35:(5-15):(5-10):(3-5):(0.5-1.5), and the initiator is benzoyl.

[0013] Preferably, in step S2, the mass ratio of polydimethylsiloxane, material A and water-based epoxy ester resin is (0.1-1):(3-6):(20-30), and the polycondensation reaction in step S2 is carried out at 45-55° C. and 650-750 RPM.

[0014] Preferably, the preparation method of the modified nano-boron carbide comprises the following steps: adding nano-B4C powder to a solvent for ultrasonic dispersion, adding to a silane coupling agent for stirring, filtering at room temperature, and finally washing and drying to obtain modified nano-boron carbide.

[0015] Preferably, the modified nano-boron carbide comprises the following raw materials in parts by weight: 0.1-1 parts of nano-B4C powder, 15-25 parts of solvent, and 1-5 parts of silane coupling agent. The particle size of the nano-B4C powder is 35-45 nm, and the silane coupling agent is KH-550.

[0016] Preferably, the ultrasonic dispersion is performed by adding the nano B4C powder to anhydrous ethanol and then ultrasonically treating the mixture at a power of 30-50% for 20-30 minutes.

[0017] Preferably, the washing is performed by washing with anhydrous ethanol and filtering for 3-5 times, and the drying is performed in a thermostat at 50-60° C. for 1-2 hours.

[0018] In addition, the present invention also provides a method for preparing a coating having anti-corrosion performance, comprising the following steps:

[0019] Add lubricant, modified nano boron carbide and fumed silica to waterborne epoxy modified acrylic resin in sequence, stir at room temperature for 10-30 minutes, add nano bentonite, stir for 0.5-1 hour, grind and let stand to obtain a coating with anti-corrosion performance.

[0020] Preferably, the lubricant is polyethylene glycol 400, and the grinding is performed to a particle size of 30-100 μm.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The invention adds waterborne epoxy modified acrylic resin, modified nano boron carbide, fumed silica and nano bentonite, polymerizes waterborne epoxy modified acrylic resin and waterborne epoxy ester resin by polydimethylsiloxane to obtain a polymer emulsion with good corrosion resistance, good permeability and good film-forming performance, and at the same time, the hydroxyl group in the silane coupling agent on the surface of the nano boron carbide fully reacts with the surface active group of the nano boron carbide, so that the nano boron carbide is highly and evenly dispersed in the waterborne coating, the agglomeration of the nano boron carbide in the coating is avoided, and the density, hardness, wear resistance and other properties are enhanced. DETAILED DESCRIPTION

[0023] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Example 1.

[0025] The coating with anti-corrosion performance of this embodiment includes the following raw materials by weight: 35 parts of water-based epoxy-modified acrylic resin, 1 part of modified nano boron carbide, 1 part of fumed silica, and 1 part of nano bentonite.

[0026] The preparation method of the waterborne epoxy-modified acrylic resin of the present embodiment comprises the following steps:

[0027] S1, polymerizing epoxy resin, methyl methacrylate, styrene, acrylic acid and initiator to obtain material A;

[0028] S2. Add polydimethylsiloxane to material A and water-based epoxy ester resin, mix and carry out polycondensation reaction to obtain water-based epoxy modified acrylic resin.

[0029] In step S1 of this embodiment, the mass ratio of epoxy resin, methyl methacrylate, styrene, acrylic acid and initiator is 35:5:5:3:0.5, and the initiator is benzoyl.

[0030] In step S2 of this embodiment, the mass ratio of polydimethylsiloxane, material A and water-based epoxy ester resin is 0.1:3:20, and the polycondensation reaction in step S2 is carried out at 45° C. and 650 RPM.

[0031] The preparation method of the modified nano-boron carbide of this embodiment comprises the following steps: adding nano-B4C powder to a solvent for ultrasonic dispersion, adding to a silane coupling agent for stirring, filtering at room temperature, and finally washing and drying to obtain modified nano-boron carbide.

[0032] The modified nano-boron carbide of this embodiment includes the following raw materials in parts by weight: 0.1 parts of nano-B4C powder, 15 parts of solvent, and 1 part of silane coupling agent. The particle size of the nano-B4C powder is 35 nm, and the silane coupling agent is KH-550.

[0033] The ultrasonic dispersion in this example is to add the nano B4C powder to anhydrous ethanol and then perform ultrasonic treatment at 30% power for 20 minutes.

[0034] In this embodiment, the washing was performed with anhydrous ethanol and filtered three times, and then dried in a thermostat at 50° C. for 1 hour.

[0035] The method for preparing a coating with anti-corrosion performance in this embodiment comprises the following steps: adding a lubricant, modified nano boron carbide, and fumed silica to a water-based epoxy-modified acrylic resin in sequence, stirring at room temperature for 10 minutes, adding nano bentonite, stirring for 0.5 hours, grinding, and standing to obtain a coating with anti-corrosion performance.

[0036] The lubricant in this embodiment is polyethylene glycol 400, which is ground to a particle size of 30 μm.

[0037] Example 2.

[0038] The coating with anti-corrosion performance of the present embodiment comprises the following raw materials, measured by weight: 35-55 parts of waterborne epoxy modified acrylic resin, 1-8 parts of modified nano boron carbide, 1-6 parts of fumed silica, and 1-5 parts of nano bentonite.

[0039] The preparation method of the waterborne epoxy-modified acrylic resin of the present embodiment comprises the following steps:

[0040] S1, polymerizing epoxy resin, methyl methacrylate, styrene, acrylic acid and initiator to obtain material A;

[0041] S2. Add polydimethylsiloxane to material A and water-based epoxy ester resin, mix and carry out polycondensation reaction to obtain water-based epoxy modified acrylic resin.

[0042] In step S1 of this embodiment, the mass ratio of epoxy resin, methyl methacrylate, styrene, acrylic acid and initiator is 35:15:10:5:1.5, and the initiator is benzoyl.

[0043] In step S2 of this embodiment, the mass ratio of polydimethylsiloxane, material A and water-based epoxy ester resin is 1:6:30, and the polycondensation reaction in step S2 is carried out at 55° C. and 750 RPM.

[0044] The preparation method of the modified nano-boron carbide of this embodiment comprises the following steps: adding nano-B4C powder to a solvent for ultrasonic dispersion, adding to a silane coupling agent for stirring, filtering at room temperature, and finally washing and drying to obtain modified nano-boron carbide.

[0045] The modified nano-boron carbide of this embodiment includes the following raw materials in parts by weight: 1 part of nano-B4C powder, 25 parts of solvent, and 5 parts of silane coupling agent. The particle size of the nano-B4C powder is 45 nm, and the silane coupling agent is KH-550.

[0046] The ultrasonic dispersion in this embodiment is to add the nano B4C powder to anhydrous ethanol and then perform ultrasonic treatment at 50% power for 30 minutes.

[0047] In this embodiment, the washing was performed with anhydrous ethanol and filtered 5 times, and then dried in a thermostat at 60° C. for 2 h.

[0048] The preparation method of a coating with anti-corrosion performance in this embodiment includes the following steps: adding a lubricant, modified nano boron carbide, and fumed silica to a water-based epoxy-modified acrylic resin in sequence, stirring at room temperature for 30 minutes, adding nano bentonite, stirring for 1 hour, grinding, and standing to obtain a coating with anti-corrosion performance.

[0049] The lubricant in this embodiment is polyethylene glycol 400, which is ground to a particle size of 100 μm.

[0050] Example 3.

[0051] The coating with anti-corrosion performance of this embodiment includes the following raw materials by weight: 45 parts of water-based epoxy-modified acrylic resin, 4.5 parts of modified nano boron carbide, 3.5 parts of fumed silica, and 3 parts of nano bentonite.

[0052] The preparation method of the waterborne epoxy-modified acrylic resin of the present embodiment comprises the following steps:

[0053] S1, polymerizing epoxy resin, methyl methacrylate, styrene, acrylic acid and initiator to obtain material A;

[0054] S2. Add polydimethylsiloxane to material A and water-based epoxy ester resin, mix and carry out polycondensation reaction to obtain water-based epoxy modified acrylic resin.

[0055] In step S1 of this embodiment, the mass ratio of epoxy resin, methyl methacrylate, styrene, acrylic acid and initiator is 35:10:7.5:4:1, and the initiator is benzoyl.

[0056] In step S2 of this embodiment, the mass ratio of polydimethylsiloxane, material A and water-based epoxy ester resin is 0.55:4.5:25, and the polycondensation reaction in step S2 is carried out at 50° C. and 700 RPM.

[0057] The preparation method of the modified nano-boron carbide of this embodiment comprises the following steps: adding nano-B4C powder to a solvent for ultrasonic dispersion, adding to a silane coupling agent for stirring, filtering at room temperature, and finally washing and drying to obtain modified nano-boron carbide.

[0058] The modified nano-boron carbide of this embodiment includes the following raw materials in parts by weight: 0.5 parts of nano-B4C powder, 20 parts of solvent, and 3 parts of silane coupling agent. The particle size of the nano-B4C powder is 40 nm, and the silane coupling agent is KH-550.

[0059] The ultrasonic dispersion in this example is to add the nano B4C powder to anhydrous ethanol and then perform ultrasonic treatment at 40% power for 25 minutes.

[0060] The washing in this embodiment is performed by washing with anhydrous ethanol and filtering 4 times, and drying is performed in a constant temperature box at 55° C. for 1.5 hours.

[0061] The preparation method of a coating with anti-corrosion performance in this embodiment comprises the following steps: adding a lubricant, modified nano boron carbide, and fumed silica to a water-based epoxy-modified acrylic resin in sequence, stirring at room temperature for 20 minutes, adding nano bentonite, stirring for 0.8 hours, grinding, and standing to obtain a coating with anti-corrosion performance.

[0062] The lubricant in this embodiment is polyethylene glycol 400, which is ground to a particle size of 65 μm.

[0063] Comparative Example 1

[0064] The difference from Example 3 is that in step S2, the polydimethylsiloxane is added in such a way that the polydimethylsiloxane is mixed before material A and then the water-based epoxy ester resin is added and mixed.

[0065] Comparative Example 2

[0066] The difference from Example 3 is that the nano boron carbide is not modified.

[0067] Comparative Example 3

[0068] The difference from Example 3 is that fumed silica is not added, but fumed silica is replaced by ordinary silicon oxide.

[0069] The anti-corrosion coatings prepared by the preparation methods in Examples 1-3 and Comparative Examples 1-3 were respectively tested for their performance:

[0070] A Q235 steel sheet with a size of 150mm*100mm*1mm was polished with 400 mesh fine sandpaper, scrubbed with ethanol and dried to obtain a pretreated Q235 steel sheet, 3-aminopropyltriethylsilane was added to the anti-corrosion coating obtained by the preparation method in Example 1-3 and Comparative Example 1-3, and stirred for 10 minutes. The ratio of coating to curing agent was 10:1; the coating with curing agent was evenly sprayed on the pretreated steel sheet by spraying, baked at 200°C for 2 minutes, and quickly immersed in 30°C cold water for 10 seconds to obtain the anti-corrosion and wear-resistant coating corresponding to the method of Example 1-3 and Comparative Example 1-3. The coating film thickness was 25μm, and wear resistance and salt spray resistance tests were carried out.

[0071] Neutral salt spray resistance test

[0072] The anticorrosive coatings prepared by the preparation methods of Examples 1-3 and Comparative Examples 1-3 were applied to steel sheets according to the above-mentioned application method to obtain six steel sheet samples of Examples 1-3 and Comparative Examples 1-3, and the test data were averaged. According to the national standard GB / T 1771-2007 "Paints and varnishes, determination of neutral salt spray resistance", the neutral salt spray resistance performance test was carried out in 2.0%, 3.0%, and 4.0wt.% NaCl aqueous solutions, and the test results are shown in Table 1.

[0073] The steel sample was placed in a salt spray chamber with the coating facing upwards and the angle with the vertical being 20°; the temperature of the salt spray chamber was 35°C and the salt spray pressure was 1kg / cm 2 , gas source is 5kg / cm 2 , use atomized 2.0wt.%, 3.0wt.%, 4.0wt.% NaCl aqueous solution to spray periodically and continuously, and the fine mist settles evenly on the surface of the sample under the action of its own weight; during the spraying period, the salt spray box is not heated and the changes in the substrate of the coating sample are observed. The steel sample is regularly observed and the time when the corrosion phenomenon begins to appear is recorded. In the neutral salt spray resistance test, the longer the time of the first corrosion phenomenon, the better the anti-corrosion performance of the coating.

[0074] Table 1

[0075]

[0076] According to the above table, it can be seen that changing the timing of adding polydimethylsiloxane in Comparative Example 1, not modifying the nano boron carbide in Comparative Example 2, and replacing meteorological silica with ordinary silicon oxide in Comparative Example 3 can greatly affect the corrosion resistance of the prepared coating, and its anti-corrosion performance is far inferior to the anti-corrosion coating prepared by the present invention.

[0077] Wear resistance test

[0078] The anticorrosive coatings prepared by the preparation methods in Examples 1-3 and Comparative Examples 1-3 were applied to steel sheets according to the above-mentioned application method to obtain six steel sheet samples of Examples 1-3 and Comparative Examples 1-3, and the test data were averaged. The wear resistance of the coating was measured according to the national standard GB / T1768-2006 "Paints and varnishes, determination of wear resistance, rotating rubber grinding wheel method", and the wear resistance test results are shown in Table 2.

[0079] The paint film wear tester was used for testing. Before the test, the wear tester was connected to the vacuum cleaner, and the working turntable was cleaned, and 400g, 500g, and 600g weights and grinding wheels were added to the pressure arm; the weight of the steel sample before the test was weighed with an analytical balance, accurate to 0.1mg; the iron sheet was then fixed on the turntable, and the pressure arm was gently lowered to ensure that the grinding wheel on the pressure arm was in full contact with the iron sheet, and the dust nozzle was lowered to a distance of 1.5mm from the steel surface; the power of the wear tester and the vacuum cleaner was turned on, the turntable speed was set to 60r / min, the running number was set to 500, the running time was set to 1 hour, and the instrument was started; after the operation was completed, the working turntable stopped automatically, the pressure arm and the dust nozzle were raised, and the residual grinding chips on the iron sheet were removed with lint-free paper, and the steel sample was weighed again, accurate to 0.1mg; the difference between the two weighing results was the mass loss of the coating, which could be used as a result of the wear resistance of the coating; the smaller the mass loss, the better the wear resistance of the coating.

[0080] Table 2

[0081]

[0082] According to the above table, it can be seen that in Comparative Example 3, the meteorological silica is replaced by ordinary silicon oxide, and the adhesion of the prepared coating is significantly reduced. In Comparative Example 2, the nano boron carbide is not modified, which greatly reduces the wear resistance of the coating. In Comparative Example 1, the timing of adding polydimethylsiloxane is changed, which causes the nano-matter to agglomerate, thereby reducing the overall wear resistance of the coating.

[0083] The invention adds waterborne epoxy modified acrylic resin, modified nano boron carbide, fumed silica and nano bentonite, polymerizes waterborne epoxy modified acrylic resin and waterborne epoxy ester resin by polydimethylsiloxane to obtain a polymer emulsion with good corrosion resistance, good permeability and good film-forming performance, and at the same time, the hydroxyl group in the silane coupling agent on the surface of the nano boron carbide fully reacts with the surface active group of the nano boron carbide, so that the nano boron carbide is highly and evenly dispersed in the waterborne coating, the agglomeration of the nano boron carbide in the coating is avoided, and the density, hardness, wear resistance and other properties are enhanced.

[0084] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0085] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A coating with anti-corrosion performance, characterized in that: The following raw materials are included by weight: 35-55 parts of waterborne epoxy modified acrylic resin, 1-8 parts of modified nano boron carbide, 1-6 parts of fumed silica, and 1-5 parts of nano bentonite.

2. A coating with anti-corrosion properties according to claim 1, characterized in that: The preparation method of the waterborne epoxy-modified acrylic resin comprises the following steps: S1, polymerizing epoxy resin, methyl methacrylate, styrene, acrylic acid and initiator to obtain material A; S2. Add polydimethylsiloxane to material A and water-based epoxy ester resin, mix and carry out polycondensation reaction to obtain water-based epoxy modified acrylic resin.

3. A coating with anti-corrosion performance according to claim 2, characterized in that: In the step S1, the mass ratio of epoxy resin, methyl methacrylate, styrene, acrylic acid and initiator is 35:(5-15):(5-10):(3-5):(0.5-1.5), and the initiator is benzoyl.

4. The coating with anti-corrosion performance according to claim 2, characterized in that: The mass ratio of polydimethylsiloxane, material A and water-based epoxy ester resin in step S2 is (0.1-1):(3-6):(20-30), and the polycondensation reaction in step S2 is carried out at 45-55° C. and 650-750 RPM.

5. The coating with anti-corrosion performance according to claim 1, characterized in that: The preparation method of the modified nano boron carbide comprises the following steps: adding nano B4C powder into a solvent for ultrasonic dispersion, adding into a silane coupling agent for stirring, filtering at room temperature, and finally washing and drying to obtain the modified nano boron carbide.

6. The coating with anti-corrosion performance according to claim 5, characterized in that: The modified nano boron carbide comprises the following raw materials in parts by weight: 0.1-1 part of nano B4C powder, 15-25 parts of solvent, and 1-5 parts of silane coupling agent. The particle size of the nano B4C powder is 35-45nm, and the silane coupling agent is KH-550.

7. The coating with anti-corrosion performance according to claim 5, characterized in that: The ultrasonic dispersion is performed by adding the nano B4C powder to anhydrous ethanol and then ultrasonically treating the mixture at a power of 30-50% for 20-30 minutes.

8. The coating with anti-corrosion performance according to claim 5, characterized in that: The washing is performed by washing with anhydrous ethanol and filtering for 3-5 times, and the drying is performed in a constant temperature box at 50-60° C. for 1-2 hours.

9. A method for preparing a coating with anti-corrosion performance according to any one of claims 1 to 8, characterized in that: The following steps are involved: Add lubricant, modified nano boron carbide and fumed silica to waterborne epoxy modified acrylic resin in sequence, stir at room temperature for 10-30 minutes, add nano bentonite, stir for 0.5-1 hour, grind and let stand to obtain a coating with anti-corrosion performance.

10. The method for preparing a coating with anti-corrosion performance according to claim 9, characterized in that: The lubricant is polyethylene glycol 400, and the grinding is performed to a particle size of 30-100 μm.

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