A highly wear-resistant and antibacterial powder coating and its preparation method

Abstract

The present invention belongs to the technical field of powder coatings, and specifically relates to a highly wear-resistant and antibacterial powder coating and a preparation method thereof. After mixing polyester resin and epoxy resin, the composite particles of the present invention are added, which have good bonding performance with the resin and dispersion performance. If the composite particles are first mixed with polydimethylsiloxane and a silane coupling agent and then added to the resin during mixing, the bonding strength and filling effect are significantly improved. After use, if the coating is subjected to long-term or strong friction, a certain amount of heat is generated on the surface of the coating, which will cause the polyvinylidene chloride to produce a certain amount of hydrogen chloride, and will cause the polyisoimide to isomerize into polyimide, thereby enhancing the wear resistance of the coating. Polydimethylsiloxane forms a silicone-like substance on the surface of silicon dioxide, which firstly enhances the bonding strength of the coating powder and secondly cooperates with other substances to enhance the overall performance of the powder coating.

Description

Technical Field

[0001] The invention belongs to the technical field of powder coatings, and particularly relates to a highly wear-resistant and antibacterial powder coating and a preparation method thereof. Background Art

[0002] Powder coating is a solid powdered synthetic resin coating composed of solid resin, filler and additives. Unlike ordinary solvent-based coatings and water-based coatings, its dispersion medium is air instead of solvent and water. It has the characteristics of no solvent pollution, 100% film formation and low energy consumption, and has very large market potential.

[0003] With the advancement of modern science and technology, powder coatings are finding increasing application in a wide range of applications, including high-speed trains, turbine and engine impellers, ship propellers, turbine generator blades, ship decks, building floors, and road markings. However, these materials are subject to significant wear and tear from high-speed airflow, sand, and water flow, as well as mechanical forces. To extend their service life, wear-resistant coatings applied to these materials must possess wear-resistant properties. Wear-resistant powder coatings are a key component of this new coatings landscape.

[0004] Existing powder coatings are susceptible to surface damage in humid climates and temperatures suitable for the growth of bacteria, mold, and other harmful microorganisms. This can lead to discoloration, powdering, and flaking, negating their primary protective and decorative properties for the substrate. Furthermore, the growth and reproduction of harmful fungi on the coating can also pose a health risk. Therefore, antimicrobial agents are often added to enhance their antimicrobial properties. However, current antimicrobial agents offer poor wear resistance, which reduces the overall performance of antimicrobial powder coatings. Summary of the Invention

[0005] To address the above problems, the present invention discloses a highly wear-resistant antibacterial powder coating and a preparation method thereof. The highly wear-resistant antibacterial powder coating prepared using the raw materials of the present invention has a strong bonding strength between the components, which not only ensures antibacterial properties but also improves wear resistance and overall performance.

[0006] Specifically, the first aspect of the present disclosure is to provide a highly wear-resistant and antibacterial powder coating, characterized in that the powder coating comprises the following raw materials in parts by weight, including the following components: 70 to 90 parts of polyester resin, 50 to 60 parts of epoxy resin, 25 to 32 parts of composite particles, 12 to 21 parts of polyisoimide, 10 to 13 parts of triethylamine, 6 to 9 parts of curing agent, 2 to 4 parts of polydimethylsiloxane, 1 to 3 parts of antibacterial agent, 1 to 2 parts of polyvinylidene chloride, and 0.3 to 0.6 parts of silane coupling agent.

[0007] In one embodiment, the powder coating comprises the following raw materials in parts by weight, including the following components: 78-83 parts of polyester resin, 53-57 parts of epoxy resin, 29-31 parts of composite particles, 17-20 parts of polyisoimide, 12 parts of triethylamine, 8 parts of curing agent, 2 parts of antibacterial agent, 2.5 parts of polydimethylsiloxane, 1.7 parts of polyvinylidene chloride, and 0.5 part of silane coupling agent.

[0008] In one embodiment, the composite particles are obtained by uniformly mixing porous silica, titanium dioxide sol, and zinc hydroxide gel in a mass ratio of 10-16:7-13:1-3, drying, calcining, grinding, and sieving.

[0009] In one embodiment, the porous silica has a particle size of 5 to 8 μm, a pore diameter of 15 to 20 nm, and a porosity of 70%.

[0010] In one embodiment, the calcination temperature is 800-850° C., and the calcination temperature is 2 hours.

[0011] In one embodiment, the curing agent is methyltetrahydrophthalic anhydride.

[0012] In one embodiment, the silane coupling agent is silane coupling agent KH570 or silane coupling agent KH550.

[0013] The second aspect of the present disclosure provides a preparation method for preparing a highly wear-resistant and antibacterial powder coating, comprising the following steps: mixing composite particles, polydimethylsiloxane, polyvinylidene chloride, and a silane coupling agent, and then adding polyester resin, epoxy resin, polyisoimide, triethylamine, a curing agent, and an antibacterial agent to obtain a highly wear-resistant powder coating.

[0014] The above and other features, aspects and advantages of the present application will be more readily understood with reference to the following detailed description. Specific implementation plan

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. In the event of a conflict, the definitions in this specification shall prevail.

[0016] Unless otherwise indicated, all percentages, parts, ratios, etc. are by weight.

[0017] As used herein, the terms "comprises," "comprising," "having," "having," "containing," or any other variations thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may also include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0018] When a quantity, part by weight or other numerical value or parameter is given as a range, a preferred range or a series of upper preferred values ​​and lower preferred values, it should be understood that it specifically discloses all ranges formed by any pair of numerical values ​​of any larger range limit or preferred value and any smaller range limit or preferred value, regardless of whether the range is disclosed separately. For example, when describing a range of "1 to 5", the described range should be understood to include a range of "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. Unless otherwise stated, where a numerical range is described herein, the range is intended to include the range end values ​​and all integers, fractions, decimals, etc. within the range.

[0019] In addition, the indefinite articles "a" and "an" before the elements or components of the present disclosure are intended to indicate that the number of occurrences (i.e., occurrences) of the elements or components is not limited. Therefore, "a" or "an" should be understood to include one or at least one, and unless it is clearly indicated that the number is singular, the elements or components in the singular also include plural cases.

[0020] Unless otherwise specified, the materials, methods, and examples described herein are illustrative only and not limiting. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present disclosure, suitable methods and materials are described herein.

[0021] The present disclosure is described in detail below.

[0022] A highly wear-resistant and antibacterial powder coating comprises the following raw materials in parts by weight, including the following components: 70 to 90 parts of polyester resin, 50 to 60 parts of epoxy resin, 25 to 32 parts of composite particles, 12 to 21 parts of polyisoimide, 12 parts of triethylamine, 6 to 9 parts of curing agent, 1 to 3 parts of antibacterial agent, 2 to 4 parts of polydimethylsiloxane, 1 to 2 parts of polyvinylidene chloride, and 0.3 to 0.6 parts of silane coupling agent.

[0023] In order to better obtain the wear-resistant effect, the weight proportion of the raw materials of the highly wear-resistant and antibacterial powder coating can be further reduced, including the following components: 78-83 parts of polyester resin, 53-57 parts of epoxy resin, 29-31 parts of composite particles, 17-20 parts of polyisoimide, 12 parts of triethylamine, 8 parts of curing agent, 2.5 parts of polydimethylsiloxane, 2 parts of antibacterial agent, 1.7 parts of polyvinylidene chloride, and 0.5 parts of silane coupling agent.

[0024] During the experiment, it was found that the better ratio of the raw materials was: 83 parts of polyester resin, 57 parts of epoxy resin, 31 parts of composite particles, 20 parts of polyisoimide, 12 parts of triethylamine, 8 parts of curing agent, 2.5 parts of polydimethylsiloxane, 2 parts of antibacterial agent, 1.7 parts of polyvinylidene chloride, and 0.5 parts of silane coupling agent.

[0025] The highly wear-resistant and antibacterial powder coating prepared under this component ratio has better performance, so that the ratio between the various components of the powder coating reaches a relatively good state. Of course, by further improving the proportion components, a better proportion effect may be obtained.

[0026] The composite particles of the present invention are prepared by uniformly mixing porous silica, titanium dioxide sol and zinc hydroxide gel in a mass ratio of 10-16:7-13:1-3, drying, calcining at 800-850° C. for 2 hours, grinding, passing through a 500-mesh sieve, and collecting the sieved particles to obtain composite particles.

[0027] The epoxy resin adopts bisphenol A epoxy resin; the viscosity of the polyester resin is preferably selected to be 7000-11000mPas, and the acid value is ≤4mgKOH / g.

[0028] The present disclosure unexpectedly discovered that after the polyester resin and the epoxy resin are mixed, the composite particles of the present disclosure are added, which have excellent bonding properties and dispersion properties with the resin. If the composite particles are first mixed with polydimethylsiloxane and a silane coupling agent and then added to the resin during mixing, the bonding strength and filling effect are significantly improved. Secondly, after the present disclosure is used, if the coating is subjected to long-term or strong friction, a certain amount of heat is generated on the coating surface, which will cause the polyvinylidene chloride to produce a certain amount of hydrogen chloride. Through the catalytic effect of the particles and the effect of hydrogen chloride, the polyisoimide isomerizes into polyimide, thereby enhancing the wear resistance of the coating. At the same time, the added triethylamine acts as a promoter and can also react with the generated hydrogen chloride to avoid the adverse effects of the generated hydrogen chloride on the coating, which has already caused damage to the coating, while increasing the antibacterial effect and improving the antibacterial performance. Secondly, polydimethylsiloxane forms a silicone glue-like substance on the surface of the composite particles, which firstly enhances the bonding strength of the coating powder and secondly cooperates with other substances to enhance the overall performance of the powder coating.

[0029] The titanium dioxide sol and zinc hydroxide gel in the present invention are prepared by conventional means in the art.

[0030] For example, titanium dioxide sol can be prepared by the following method: tetrabutyl titanate, anhydrous ethanol, diethanolamine, and water are mixed in a molar ratio of 1:23:3:10, and then water and the remaining anhydrous ethanol are added. The mixture is stirred for 2 hours and allowed to stand to obtain titanium dioxide sol.

[0031] For example, zinc hydroxide gel can be prepared by the following method: a 10% by mass zinc acetate aqueous solution and an 8% by mass oxalic acid anhydrous ethanol solution are mixed in a volume ratio of 1:2, and then triammonium citrate with a mass fraction of 10% of the zinc acetate is added, stirred evenly, kept warm at 80°C, and filtered to obtain zinc hydroxide gel.

[0032] There is no particular limitation on the porous silica, which may be any of those commonly used in the art. Advantageously, the porous silica has a particle size of 5 to 8 μm, a pore size of 15 to 20 nm, and a porosity of 70%.

[0033] The porous silica with this physical property has good loading performance, dispersibility and bonding performance with raw materials. If the selected particle size, pore size and porosity are larger or smaller than the porous silica used in the present invention, it will always cause a slight reduction in a certain property of the powder coating.

[0034] There are no particular limitations on the curing agent, and it can be any conventional curing agent used in the art, such as dihydrazide adipic acid, triglycidyl isocyanurate, phenolic curing agents, etc. Advantageously, the curing agent is methyltetrahydrophthalic anhydride, and the addition of this curing agent can effectively enhance the curing effect.

[0035] There is no particular limitation on the silane coupling agent, which may be any of those commonly used in the art. Advantageously, the silane coupling agent is silane coupling agent KH570 or silane coupling agent KH550, which can increase the bonding strength between the particles and the resin.

[0036] There is no particular limitation on the antimicrobial agent, which may be any of those commonly used in the art, such as inorganic antimicrobial agents that utilize the bactericidal or bacteriostatic properties of metal ions such as silver, zinc, copper, and titanium.

[0037] The second aspect of the present disclosure provides a preparation method for preparing a highly wear-resistant powder coating, comprising the following steps: mixing composite particles, polydimethylsiloxane, polyvinylidene chloride, and a silane coupling agent, and then adding polyester resin, epoxy resin, polyisoimide, triethylamine, a curing agent, and an antibacterial agent to obtain a highly wear-resistant powder coating.

[0038] Example 1

[0039] A highly wear-resistant and antibacterial powder coating comprises the following raw materials in parts by weight, including the following components: 70 parts of polyester resin, 50 parts of epoxy resin, 25 parts of composite particles, 12 parts of polyisoimide, 12 parts of triethylamine, 6 parts of curing agent, 2 parts of polydimethylsiloxane, 2 parts of antibacterial agent, 1 part of polyvinylidene chloride, and 0.3 parts of silane coupling agent.

[0040] Example 2

[0041] A highly wear-resistant and antibacterial powder coating comprises the following raw materials in parts by weight, including the following components: 78 parts of polyester resin, 53 parts of epoxy resin, 29 parts of composite particles, 17 parts of polyisoimide, 12 parts of triethylamine, 8 parts of curing agent, 2.5 parts of polydimethylsiloxane, 2 parts of antibacterial agent, 1.7 parts of polyvinylidene chloride, and 0.5 parts of silane coupling agent.

[0042] Example 3

[0043] Highly wear-resistant and antibacterial powder coating, the powder coating includes the following raw materials in the following parts by weight, including the following components: 83 parts of polyester resin, 57 parts of epoxy resin, 31 parts of composite particles, 20 parts of polyisoimide, 12 parts of triethylamine, 8 parts of curing agent, 2.5 parts of polydimethylsiloxane, 2 parts of antibacterial agent, 1.7 parts of polyvinylidene chloride, and 0.5 parts of silane coupling agent.

[0044] Example 4

[0045] A highly wear-resistant and antibacterial powder coating comprises the following raw materials in parts by weight, including the following components: 90 parts of polyester resin, 60 parts of epoxy resin, 32 parts of composite particles, 21 parts of polyisoimide, 12 parts of triethylamine, 9 parts of curing agent, 4 parts of polydimethylsiloxane, 2 parts of antibacterial agent, 2 parts of polyvinylidene chloride, and 0.6 parts of silane coupling agent.

[0046] Example 5

[0047] It is basically the same as Example 3, the only difference being that the composite particles are prepared by mixing porous silica, nano-titanium dioxide, and nano-zinc oxide according to the proportions in Example 3.

[0048] Example 6

[0049] Highly wear-resistant and antibacterial powder coating, the powder coating comprises the following raw materials in parts by weight, including the following components: 83 parts of polyester resin, 57 parts of epoxy resin, 31 parts of composite particles, 20 parts of polyisoimide, 12 parts of triethylamine, 8 parts of curing agent, 1.7 parts of polyvinylidene chloride, 2 parts of antibacterial agent, and 0.5 parts of silane coupling agent.

[0050] Example 7

[0051] Highly wear-resistant and antibacterial powder coating, the powder coating includes the following raw materials in parts by weight, including the following components: 83 parts of polyester resin, 57 parts of epoxy resin, 31 parts of composite particles, 20 parts of polyisoimide, 12 parts of triethylamine, 8 parts of curing agent, 2.5 parts of polydimethylsiloxane, 2 parts of antibacterial agent, and 0.5 part of silane coupling agent.

[0052] Example 8

[0053] Highly wear-resistant and antibacterial powder coating, the powder coating comprises the following raw materials in parts by weight, including the following components: 83 parts of polyester resin, 57 parts of epoxy resin, 31 parts of composite particles, 12 parts of triethylamine, 8 parts of curing agent, 2.5 parts of polydimethylsiloxane, 1.7 parts of polyvinylidene chloride, 2 parts of antibacterial agent, and 0.5 parts of silane coupling agent.

[0054] Examples 1 to 8 are respectively prepared according to the following steps: mixing composite particles, polydimethylsiloxane, polyvinylidene chloride, and a silane coupling agent, and then adding polyester resin, epoxy resin, polyisoimide, triethylamine, an antibacterial agent, and a curing agent to obtain a highly wear-resistant powder coating.

[0055] Example 9

[0056] The difference from Example 3 is that the preparation method is different. The preparation method is to directly mix the raw materials to obtain a highly wear-resistant and antibacterial powder coating.

[0057] The high wear-resistant antibacterial powder coatings prepared in Examples 1 to 9 were subjected to the following tests:

[0058] First, each high wear-resistant antibacterial powder coating is applied to a 0.8 mm thick cold-rolled steel plate that has undergone standard pre-treatment, with a coating thickness of 60 to 80 μm.

[0059] Wear resistance: GB / T 1768-2006, 2kg*4000 revolutions, weight loss detection.

[0060] Acid and alkali resistance: GB 1763-79(89) is adopted.

[0061] Coating appearance: visual inspection.

[0062] Adhesion: GB / T 9286-1998.

[0063] Antibacterial performance: in accordance with the national standard GB / T 21866-2008 Antibacterial coatings (paint films) antibacterial property determination method and antibacterial effect;

[0064] The test results are shown in the following table:

[0065] Coating appearance Weight loss / g Acid and alkali resistance Adhesion Antibacterial activity / % Example 1 Smooth 0.008 No bubbles, no wrinkles 5 99.2 Example 2 Smooth 0.006 No bubbles, no wrinkles 5 99.1 Example 3 Smooth 0.002 No bubbles, no wrinkles 5 99.4 Example 4 Smooth 0.011 No bubbles, no wrinkles 5 98.1 Example 5 Smooth 0.032 No bubbles, no wrinkles, slight surface loss 4 94.6 Example 6 Smooth 0.019 No bubbles, no wrinkles 4 96.2 Example 7 Smooth 0.029 Slight bubbling, no wrinkling, slight gloss loss 4 95.3 Example 8 Smooth 0.035 No bubbles, no wrinkles 4 93.1 Example 9 Smooth 0.018 No bubbles, no wrinkles 4 98.5

[0066] The experimental data in the above table show that the raw materials in the present invention interact and cooperate with each other, thereby effectively improving the overall performance. At the same time, the product disclosed in the present invention effectively solves the technical problems existing in the prior art.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A highly wear-resistant and antibacterial powder coating, characterized in that: The powder coating comprises the following raw materials in parts by weight, including the following components: 70-90 parts of polyester resin, 50-60 parts of epoxy resin, 25-32 parts of composite particles, 12-21 parts of polyisoimide, 10-13 parts of triethylamine, 6-9 parts of curing agent, 2-4 parts of polydimethylsiloxane, 1-3 parts of antibacterial agent, 1-2 parts of polyvinylidene chloride, and 0.3-0.6 parts of silane coupling agent. The composite particles are prepared by uniformly mixing porous silicon dioxide, titanium dioxide sol and zinc hydroxide gel in a mass ratio of 10-16:7-13:1-3, drying, calcining, grinding and sieving.

2. A highly wear-resistant and antibacterial powder coating according to claim 1, characterized in that: The powder coating comprises the following raw materials in parts by weight, including the following components: 78 to 83 parts of polyester resin, 53 to 57 parts of epoxy resin, 29 to 31 parts of composite particles, 17 to 20 parts of polyisoimide, 12 parts of triethylamine, 8 parts of curing agent, 2.5 parts of polydimethylsiloxane, 2 parts of antibacterial agent, 1.7 parts of polyvinylidene chloride, and 0.5 part of silane coupling agent.

3. The highly wear-resistant antibacterial powder coating according to claim 1, characterized in that: The porous silicon dioxide has a particle size of 5 to 8 μm, a pore diameter of 15 to 20 nm, and a porosity of 70%.

4. The highly wear-resistant antibacterial powder coating according to claim 1, characterized in that: The calcination temperature is 800-850° C., and the calcination time is 2 hours.

5. The highly wear-resistant antibacterial powder coating according to claim 1, characterized in that: The curing agent is methyltetrahydrophthalic anhydride.

6. The highly wear-resistant antibacterial powder coating according to claim 5, characterized in that: The silane coupling agent is silane coupling agent KH570 or silane coupling agent KH550.

7. A preparation method, characterized in that: The method for preparing the highly wear-resistant and antibacterial powder coating according to any one of claims 1 to 6 comprises the following steps: mixing composite particles, polydimethylsiloxane, polyvinylidene chloride, and a silane coupling agent, and then adding polyester resin, epoxy resin, polyisoimide, triethylamine, a curing agent, and an antibacterial agent to obtain a highly wear-resistant powder coating.