An ultra-wear and scratch resistant uv coating and method of making the same

Abstract

The application provides a kind of super wear-resistant scratch-resistant UV coating, which is composed of the following components by weight percentage: modified polyurethane acrylic resin 100-150 parts, active diluent 20-40 parts, photoinitiator 4-6 parts, pigment-loaded foam alumina particles 3-10 parts, BYK 331 leveling agent 3-10 parts, auxiliary 0.5-2 parts; the particle size of the pigment-loaded foam alumina particles is 10-100 μm, and the porosity of the foam alumina is 80-97%. The application proposes a kind of super wear-resistant scratch-resistant UV coating and its preparation method, which forms micro-nano structure on the surface of the coating through the micron structure of foam alumina particles, the nano structure of pigment and the micro (nano) micropore of foam alumina particles, thereby improving the tribological properties of the coating, reducing friction and wear, and improving the friction-reducing and drag-reducing performance of the coating; the foam alumina has a porous structure with abundant pore structure, which can adsorb a large amount of pigment, making the pigment disperse uniformly, avoiding agglomeration when directly added to the coating, and making the color of the coating uneven.

Description

Technical Field

[0001] This invention relates to the field of coatings, specifically to an ultra-wear-resistant and scratch-resistant UV coating and its preparation method. Background Technology

[0002] Ultraviolet (UV) curing coatings and their application technologies are new surface treatment technologies that emerged in the 1980s. These coatings utilize ultraviolet radiation to induce resin curing. Compared with existing thermosetting coatings, they offer advantages such as faster curing, energy saving, room temperature curing, less pollution, and superior coating performance, making them a new generation of green chemical products. However, with the increasing demands of modern industry for material performance, although UV-cured coatings have relatively good wear resistance, various industries have higher requirements for their wear and scratch resistance. Therefore, the development of novel ultra-wear-resistant and scratch-resistant coatings has become a research hotspot in the fields of materials science and surface engineering. These coatings typically achieve their superior performance by introducing specific nanoparticles, employing advanced coating preparation technologies (such as physical vapor deposition, chemical vapor deposition, and thermal spraying), and optimizing the microstructure of the coating. However, directly adding nanoparticles can easily lead to agglomeration, especially when the pigments are also nano-sized, resulting in uneven color and a lack of pigment protection, making them prone to fading during wear. All of these problems urgently need to be addressed. Summary of the Invention

[0003] Technical problem to be solved: This invention addresses the current technical problems of poor wear resistance and uneven color in UV coatings by proposing an ultra-wear-resistant and scratch-resistant UV coating and its preparation method. Through the micron structure of foamed alumina particles, the nanostructure of pigments, and the micro / nano pores of the foamed alumina particles, a micro / nano structure is formed on the coating surface, thereby improving the tribological properties of the coating, reducing friction and wear, and enhancing the coating's friction-reducing and drag-reducing performance. The foamed alumina has a porous structure with abundant pores, which can adsorb a large amount of pigment, ensuring uniform pigment dispersion and avoiding agglomeration caused by direct addition to the coating, thus preventing uneven color.

[0004] Technical solution: An ultra-wear-resistant and scratch-resistant UV coating, comprising the following components by weight:

[0005] 100-150 parts of modified polyurethane acrylic resin

[0006] 20-40 parts of reactive diluent

[0007] 4-6 parts of photoinitiator

[0008] 3-10 parts of pigment-loaded foamed alumina particles

[0009] BYK 331 leveling agent 3-10 parts

[0010] Additives: 0.5-2 parts;

[0011] The particle size of the pigment-loaded foamed alumina particles is 10-100 μm, and the porosity of the foamed alumina is 80-97%.

[0012] Furthermore, the modified polyurethane acrylic resin is prepared as follows, in parts by weight:

[0013] (1) Take 5 parts of hydroxyl-terminated polydimethylsiloxane, 4.5 parts of pentaerythritol triacrylate, 0.1 parts of dibutyltin dilaurate and 0.2 parts of p-hydroxyanisole, mix them, introduce N2, and stir until uniform;

[0014] (2) Heat to 80℃ and start adding 100 parts of isophorone diisocyanate dropwise, react for 3-4 hours;

[0015] (3) Add pentaerythritol triacrylate to neutralize the unreacted isocyanate groups to obtain modified polyurethane acrylic resin.

[0016] Furthermore, the active diluent is a complex of HDDA and DPHA in a ratio of 1:(1-1.5).

[0017] Furthermore, the photoinitiator is one or more of the following: a mixture of benzophenone and hydroxycyclohexylphenyl ketone, or an acylphosphide class.

[0018] Furthermore, the method for preparing the pigment-loaded foamed alumina particles is as follows:

[0019] Step 1: Soak polyurethane foam with a pore size of 100 PPI in 10-20% NaOH solution for 2-3 hours, then soak it in a constant temperature water bath at 60℃ for 3 hours. Repeatedly rub to remove the intermesh membrane, rinse with water to obtain the treated polyurethane foam.

[0020] Step 2: Take 50-80 parts of nano alumina, 5-8 parts of mesoporous alumina fiber, 3-6 parts of silicon carbide hollow microspheres, 3-5 parts of magnesium oxide, 10-15 parts of silicon micro powder and 2-5 parts of nano zirconium oxide, mix and stir evenly to obtain a mixed component, add 35-50% aluminum dihydrogen phosphate solution to form a slurry, and let the slurry stand for 12 hours;

[0021] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0022] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0023] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0024] Step 6: Take 6 parts of foamed alumina granules, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours.

[0025] Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 1-2 hours;

[0026] Step 8: Add 1.2-1.5 parts of methyl methacrylate, 20 parts of 95% ethanol and ammonium persulfate, and react for 2-3 hours;

[0027] Step 9: After filtering and drying, wash with 95% ethanol and dry to obtain pigment-loaded foamed alumina particles.

[0028] Furthermore, the nano-alumina has a particle size of 30-100nm, the silicon carbide hollow microspheres have a particle size of 400-580nm, the magnesium oxide has a particle size of 260-500nm, the silicon micropowder has a particle size of 0.5-2μm, and the nano-zirconia has a particle size of 30-80nm.

[0029] Furthermore, the surface of the mesoporous alumina fiber has mesopores of 2-4 nm and an average specific surface area of ​​322 m². 2 / g, fiber diameter is 200-300nm, and length is 7-10μm.

[0030] Furthermore, the mass of the aluminum dihydrogen phosphate solution is 20-25% of the mixed components.

[0031] Furthermore, the additive is any one or a combination of two or more of the following: defoamer, formaldehyde removal additive, and antibacterial additive.

[0032] The preparation method of the above-mentioned ultra-wear-resistant and scratch-resistant UV coating includes the following steps: after mixing the modified polyurethane acrylic resin, reactive diluent, photoinitiator, BYK331 leveling agent and additives evenly, add the pigment-loaded foamed alumina particles and stir evenly again. Beneficial effects

[0033] In this invention, pigment-loaded foamed alumina particles are added to the coating. The foamed alumina has a porous structure with abundant pores, which can adsorb a large amount of pigment, making the pigment dispersed evenly and avoiding the agglomeration that would occur if it were added directly to the coating, resulting in uneven color.

[0034] This invention utilizes the micron structure of foamed alumina particles, the nanostructure of pigments, and the micro (nano)pores of foamed alumina particles to form a micro / nano structure on the coating surface, thereby improving the tribological properties of the coating, reducing friction and wear, and enhancing the friction-reducing and drag-reducing performance of the coating.

[0035] This invention adds mesoporous alumina fibers to the preparation of foamed alumina particles. The mesoporous structure further increases the pore structure and enhances the adsorption of pigments. At the same time, the two-dimensional structure of alumina fibers can form a "skeleton" in the foamed alumina structure, bearing most of the load, reducing stress concentration, facilitating load transfer and crack dispersion, preventing or slowing crack propagation, and increasing the toughness and wear resistance of foamed alumina particles.

[0036] This invention adds silicon carbide hollow microspheres to the preparation of foamed alumina particles. The silicon carbide hollow microspheres have high strength and a higher modulus than nano-alumina, which can increase the toughness of foamed alumina particles and significantly improve their strength.

[0037] This invention improves the stability, dispersibility, and abrasion fastness of pigments by adsorbing pigments into the pores and surface of foamed alumina particles and then fixing them with polymethyl methacrylate.

[0038] This invention modifies polyurethane acrylic resin by introducing silanol groups and hydroxyl groups on the surface of the polyurethane acrylic resin, which can form a stable spatial network structure with pigment-loaded foam alumina particles, thereby enhancing the density and wear resistance of the coating. Detailed Implementation Example 1

[0039] The preparation method of pigment-loaded foamed alumina particles is as follows:

[0040] Step 1: Soak a polyurethane foam with a pore size of 100 PPI in a 20% NaOH solution for 2 hours, then soak it in a constant temperature water bath at 60°C for 3 hours. Repeatedly rub the foam to remove the intermesh membrane, rinse it with water, and obtain the treated polyurethane foam.

[0041] Step 2: Take 80 parts of nano-alumina with a particle size of 30-100nm and 5 parts of mesoporous alumina fibers (the mesoporous alumina fibers have mesopores of 2-4nm on the surface and an average specific surface area of ​​322m²). 2The mixture consists of 5 parts of hollow silicon carbide microspheres with a fiber diameter of 200-300 nm and a length of 7-10 μm, 4 parts of magnesium oxide with a particle size of 260-500 nm, 15 parts of silica powder with a particle size of 0.5-2 μm, and 5 parts of nano-zirconia with a particle size of 30-80 nm. The mixture is stirred evenly to obtain a mixed component. A 40% aluminum dihydrogen phosphate solution is added, with the mass of the aluminum dihydrogen phosphate solution being 25% of the mixed component, to form a slurry. The slurry is then allowed to stand for 12 hours.

[0042] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0043] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0044] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0045] Step 6: Take 6 parts of foamed alumina granules, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours.

[0046] Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 2 hours;

[0047] Step 8: Add 1.4 parts methyl methacrylate, 20 parts 95% ethanol and ammonium persulfate, and react for 3 hours;

[0048] Step 9: After filtration and drying, wash with 95% ethanol and dry to obtain pigment-loaded foam alumina particles with a particle size of 10-100μm. Example 2

[0049] The preparation method of pigment-loaded foamed alumina particles is as follows:

[0050] Step 1: Soak a polyurethane foam with a pore size of 100 PPI in a 20% NaOH solution for 2 hours, then soak it in a constant temperature water bath at 60°C for 3 hours. Repeatedly rub the foam to remove the intermesh membrane, rinse it with water, and obtain the treated polyurethane foam.

[0051] Step 2: Take 80 parts of nano-alumina with a particle size of 30-100nm and 7 parts of mesoporous alumina fibers (the mesoporous alumina fibers have mesopores of 2-4nm on the surface and an average specific surface area of ​​322m²). 2 The mixture consists of 5 parts of hollow silicon carbide microspheres with a fiber diameter of 200-300 nm and a length of 7-10 μm, 4 parts of magnesium oxide with a particle size of 260-500 nm, 15 parts of silica powder with a particle size of 0.5-2 μm, and 5 parts of nano-zirconia with a particle size of 30-80 nm. The mixture is stirred evenly to obtain a mixed component. A 40% aluminum dihydrogen phosphate solution is added, with the mass of the aluminum dihydrogen phosphate solution being 25% of the mixed component, to form a slurry. The slurry is then allowed to stand for 12 hours.

[0052] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0053] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0054] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0055] Step 6: Take 6 parts of foamed alumina granules, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours.

[0056] Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 2 hours;

[0057] Step 8: Add 1.4 parts methyl methacrylate, 20 parts 95% ethanol and ammonium persulfate, and react for 3 hours;

[0058] Step 9: After filtration and drying, wash with 95% ethanol and dry to obtain pigment-loaded foam alumina particles with a particle size of 10-100μm. Example 3

[0059] The preparation method of pigment-loaded foamed alumina particles is as follows:

[0060] Step 1: Soak a polyurethane foam with a pore size of 100 PPI in a 20% NaOH solution for 2 hours, then soak it in a constant temperature water bath at 60°C for 3 hours. Repeatedly rub the foam to remove the intermesh membrane, rinse it with water, and obtain the treated polyurethane foam.

[0061] Step 2: Take 80 parts of nano-alumina with a particle size of 30-100nm and 8 parts of mesoporous alumina fibers (the mesoporous alumina fibers have mesopores of 2-4nm on the surface and an average specific surface area of ​​322m²). 2 The mixture consists of 5 parts of hollow silicon carbide microspheres with a fiber diameter of 200-300 nm and a length of 7-10 μm, 4 parts of magnesium oxide with a particle size of 260-500 nm, 15 parts of silica powder with a particle size of 0.5-2 μm, and 5 parts of nano-zirconia with a particle size of 30-80 nm. The mixture is stirred evenly to obtain a mixed component. A 40% aluminum dihydrogen phosphate solution is added, with the mass of the aluminum dihydrogen phosphate solution being 25% of the mixed component, to form a slurry. The slurry is then allowed to stand for 12 hours.

[0062] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0063] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0064] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0065] Step 6: Take 6 parts of foamed alumina granules, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours.

[0066] Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 2 hours;

[0067] Step 8: Add 1.4 parts methyl methacrylate, 20 parts 95% ethanol and ammonium persulfate, and react for 3 hours;

[0068] Step 9: After filtration and drying, wash with 95% ethanol and dry to obtain pigment-loaded foam alumina particles with a particle size of 10-100μm. Example 4

[0069] The preparation method of pigment-loaded foamed alumina particles is as follows:

[0070] Step 1: Soak a polyurethane foam with a pore size of 100 PPI in a 20% NaOH solution for 2 hours, then soak it in a constant temperature water bath at 60°C for 3 hours. Repeatedly rub the foam to remove the intermesh membrane, rinse it with water, and obtain the treated polyurethane foam.

[0071] Step 2: Take 80 parts of nano-alumina with a particle size of 30-100nm and 7 parts of mesoporous alumina fibers (the mesoporous alumina fibers have mesopores of 2-4nm on the surface and an average specific surface area of ​​322m²). 2 The mixture consists of 3 parts of hollow silicon carbide microspheres with a fiber diameter of 200-300 nm and a length of 7-10 μm, 4 parts of magnesium oxide with a particle size of 260-500 nm, 15 parts of silica powder with a particle size of 0.5-2 μm, and 5 parts of nano-zirconia with a particle size of 30-80 nm. The mixture is stirred evenly to obtain a mixed component. A 40% aluminum dihydrogen phosphate solution is added, with the mass of the aluminum dihydrogen phosphate solution being 25% of the mixed component, to form a slurry. The slurry is then allowed to stand for 12 hours.

[0072] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0073] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0074] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0075] Step 6: Take 6 parts of foamed alumina granules, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours.

[0076] Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 2 hours;

[0077] Step 8: Add 1.4 parts methyl methacrylate, 20 parts 95% ethanol and ammonium persulfate, and react for 3 hours;

[0078] Step 9: After filtration and drying, wash with 95% ethanol and dry to obtain pigment-loaded foam alumina particles with a particle size of 10-100μm. Example 5

[0079] The preparation method of pigment-loaded foamed alumina particles is as follows:

[0080] Step 1: Soak a polyurethane foam with a pore size of 100 PPI in a 20% NaOH solution for 2 hours, then soak it in a constant temperature water bath at 60°C for 3 hours. Repeatedly rub the foam to remove the intermesh membrane, rinse it with water, and obtain the treated polyurethane foam.

[0081] Step 2: Take 80 parts of nano-alumina with a particle size of 30-100nm and 7 parts of mesoporous alumina fibers (the mesoporous alumina fibers have mesopores of 2-4nm on the surface and an average specific surface area of ​​322m²). 2 The mixture consists of 6 parts of hollow silicon carbide microspheres with a fiber diameter of 200-300 nm and a length of 7-10 μm, 4 parts of magnesium oxide with a particle size of 260-500 nm, 15 parts of silica powder with a particle size of 0.5-2 μm, and 5 parts of nano-zirconia with a particle size of 30-80 nm. The mixture is stirred evenly to obtain a mixed component. A 40% aluminum dihydrogen phosphate solution is added, with the mass of the aluminum dihydrogen phosphate solution being 25% of the mixed component, to form a slurry. The slurry is then allowed to stand for 12 hours.

[0082] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0083] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0084] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0085] Step 6: Take 6 parts of foamed alumina granules, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours.

[0086] Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 2 hours;

[0087] Step 8: Add 1.4 parts methyl methacrylate, 20 parts 95% ethanol and ammonium persulfate, and react for 3 hours;

[0088] Step 9: After filtration and drying, wash with 95% ethanol and dry to obtain pigment-loaded foam alumina particles with a particle size of 10-100μm. Example 6

[0089] The preparation method of pigment-loaded foamed alumina particles is as follows:

[0090] Step 1: Soak a polyurethane foam with a pore size of 100 PPI in a 20% NaOH solution for 2 hours, then soak it in a constant temperature water bath at 60°C for 3 hours. Repeatedly rub the foam to remove the intermesh membrane, rinse it with water, and obtain the treated polyurethane foam.

[0091] Step 2: Take 80 parts of nano-alumina with a particle size of 30-100nm and 7 parts of mesoporous alumina fibers (the mesoporous alumina fibers have mesopores of 2-4nm on the surface and an average specific surface area of ​​322m²). 2 The mixture consists of 5 parts of hollow silicon carbide microspheres with a fiber diameter of 200-300 nm and a length of 7-10 μm, 4 parts of magnesium oxide with a particle size of 260-500 nm, 15 parts of silica powder with a particle size of 0.5-2 μm, and 5 parts of nano-zirconia with a particle size of 30-80 nm. The mixture is stirred evenly to obtain a mixed component. A 40% aluminum dihydrogen phosphate solution is added, with the mass of the aluminum dihydrogen phosphate solution being 25% of the mixed component, to form a slurry. The slurry is then allowed to stand for 12 hours.

[0092] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0093] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0094] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0095] Step 6: Take 6 parts of foamed alumina particles, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours.

[0096] Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 2 hours;

[0097] Step 8: Add 1.2 parts methyl methacrylate, 20 parts 95% ethanol and ammonium persulfate, and react for 3 hours;

[0098] Step 9: After filtration and drying, wash with 95% ethanol and dry to obtain pigment-loaded foam alumina particles with a particle size of 10-100μm. Example 7

[0099] The preparation method of pigment-loaded foamed alumina particles is as follows:

[0100] Step 1: Soak a polyurethane foam with a pore size of 100 PPI in a 20% NaOH solution for 2 hours, then soak it in a constant temperature water bath at 60°C for 3 hours. Repeatedly rub the foam to remove the intermesh membrane, rinse it with water, and obtain the treated polyurethane foam.

[0101] Step 2: Take 80 parts of nano-alumina with a particle size of 30-100nm and 7 parts of mesoporous alumina fibers (the mesoporous alumina fibers have mesopores of 2-4nm on the surface and an average specific surface area of ​​322m²). 2 The mixture consists of 5 parts of hollow silicon carbide microspheres with a fiber diameter of 200-300 nm and a length of 7-10 μm, 4 parts of magnesium oxide with a particle size of 260-500 nm, 15 parts of silica powder with a particle size of 0.5-2 μm, and 5 parts of nano-zirconia with a particle size of 30-80 nm. The mixture is stirred evenly to obtain a mixed component. A 40% aluminum dihydrogen phosphate solution is added, with the mass of the aluminum dihydrogen phosphate solution being 25% of the mixed component, to form a slurry. The slurry is then allowed to stand for 12 hours.

[0102] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0103] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0104] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0105] Step 6: Take 6 parts of foamed alumina granules, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours.

[0106] Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 2 hours;

[0107] Step 8: Add 1.5 parts methyl methacrylate, 20 parts 95% ethanol and ammonium persulfate, and react for 3 hours;

[0108] Step 9: After filtration and drying, wash with 95% ethanol and dry to obtain pigment-loaded foam alumina particles with a particle size of 10-100μm. Comparative Example 1

[0109] The difference between this embodiment and Embodiment 2 is that mesoporous alumina fibers are not used; instead, nano-alumina is used, as detailed below:

[0110] The preparation method of pigment-loaded foamed alumina particles is as follows:

[0111] Step 1: Soak a polyurethane foam with a pore size of 100 PPI in a 20% NaOH solution for 2 hours, then soak it in a constant temperature water bath at 60°C for 3 hours. Repeatedly rub the foam to remove the intermesh membrane, rinse it with water, and obtain the treated polyurethane foam.

[0112] Step 2: Take 87 parts of nano-alumina with a particle size of 30-100nm, 5 parts of silicon carbide hollow microspheres with a particle size of 400-580nm, 4 parts of magnesium oxide with a particle size of 260-500nm, 15 parts of silicon micro powder with a particle size of 0.5-2μm, and 5 parts of nano-zirconia with a particle size of 30-80nm, mix and stir evenly to obtain a mixed component, add a 40% aluminum dihydrogen phosphate solution, the mass of the aluminum dihydrogen phosphate solution being 25% of the mixed component, to form a slurry, and let the slurry stand for 12 hours;

[0113] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0114] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0115] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0116] Step 6: Take 6 parts of foamed alumina granules, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours.

[0117] Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 2 hours;

[0118] Step 8: Add 1.4 parts methyl methacrylate, 20 parts 95% ethanol and ammonium persulfate, and react for 3 hours;

[0119] Step 9: After filtration and drying, wash with 95% ethanol and dry to obtain pigment-loaded foam alumina particles with a particle size of 10-100μm. Comparative Example 2

[0120] The difference between this embodiment and Embodiment 2 is that silicon carbide hollow microspheres are not used; instead, nano-alumina is used, as detailed below:

[0121] The preparation method of pigment-loaded foamed alumina particles is as follows:

[0122] Step 1: Soak a polyurethane foam with a pore size of 100 PPI in a 20% NaOH solution for 2 hours, then soak it in a constant temperature water bath at 60°C for 3 hours. Repeatedly rub the foam to remove the intermesh membrane, rinse it with water, and obtain the treated polyurethane foam.

[0123] Step 2: Take 85 parts of nano-alumina with a particle size of 30-100nm and 7 parts of mesoporous alumina fibers (the mesoporous alumina fibers have mesopores of 2-4nm on the surface and an average specific surface area of ​​322m²). 2 The mixture consists of 4 parts magnesium oxide with a particle size of 260-500 nm, 15 parts silica powder with a particle size of 0.5-2 μm, and 5 parts nano-zirconia with a particle size of 30-80 nm. The mixture is stirred evenly to obtain a mixed component. A 40% aluminum dihydrogen phosphate solution is added, with the mass of the aluminum dihydrogen phosphate solution being 25% of the mixed component, to form a slurry. The slurry is then allowed to stand for 12 hours.

[0124] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0125] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0126] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0127] Step 6: Take 6 parts of foamed alumina granules, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours.

[0128] Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 2 hours;

[0129] Step 8: Add 1.4 parts methyl methacrylate, 20 parts 95% ethanol and ammonium persulfate, and react for 3 hours;

[0130] Step 9: After filtration and drying, wash with 95% ethanol and dry to obtain pigment-loaded foam alumina particles with a particle size of 10-100μm. Comparative Example 3

[0131] The difference between this embodiment and Embodiment 2 is that methyl methacrylate is not used to form the shell, as detailed below:

[0132] The preparation method of pigment-loaded foamed alumina particles is as follows:

[0133] Step 1: Soak a polyurethane foam with a pore size of 100 PPI in a 20% NaOH solution for 2 hours, then soak it in a constant temperature water bath at 60°C for 3 hours. Repeatedly rub the foam to remove the intermesh membrane, rinse it with water, and obtain the treated polyurethane foam.

[0134] Step 2: Take 80 parts of nano-alumina with a particle size of 30-100nm and 7 parts of mesoporous alumina fibers (the mesoporous alumina fibers have mesopores of 2-4nm on the surface and an average specific surface area of ​​322m²). 2 The mixture consists of 5 parts of hollow silicon carbide microspheres with a fiber diameter of 200-300 nm and a length of 7-10 μm, 4 parts of magnesium oxide with a particle size of 260-500 nm, 15 parts of silica powder with a particle size of 0.5-2 μm, and 5 parts of nano-zirconia with a particle size of 30-80 nm. The mixture is stirred evenly to obtain a mixed component. A 40% aluminum dihydrogen phosphate solution is added, with the mass of the aluminum dihydrogen phosphate solution being 25% of the mixed component, to form a slurry. The slurry is then allowed to stand for 12 hours.

[0135] Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank.

[0136] Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina.

[0137] Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules;

[0138] Step 6: Take 6 parts of foamed alumina particles, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, keep at 70℃ for 1-2 hours, filter and dry to obtain pigment-loaded foamed alumina particles with a particle size of 10-100μm.

[0139] The porosity, pigment loading rate, fixation rate, and compressive strength of the pigment-loaded alumina foam particles prepared in the above embodiments were measured.

[0140] Determination of fixation rate: 1.000g of pigment-loaded foamed alumina particles were added to 95% ethanol and placed in a biological shaker at 25℃ for 7 days. After filtration, the absorbance of the filtrate was measured by spectrophotometer. The concentration was calculated based on the absorbance, and the fixation rate (%) was calculated based on the concentration difference.

[0141] The results are shown in Table 1 below:

[0142] Table 1

[0143] Porosity (%) Pigment loading rate (%) Color fixation rate (%) Compressive strength (MPa) Example 1 86.3 91.7 97.3 13.3 Example 2 85.8 92.2 97.4 13.8 Example 3 85.5 92.4 97.3 13.9 Example 4 87.1 92.5 97.3 13.5 Example 5 86.2 92.0 97.4 13.9 Example 6 86.8 92.2 95.8 13.7 Example 7 86.1 92.2 97.4 13.8 Comparative Example 1 87.0 88.3 97.1 10.4 Comparative Example 2 87.8 92.6 97.3 11.9 Comparative Example 3 87.0 92.2 82.7 13.7

[0144] Based on a comprehensive comparison of the various properties of the pigment-loaded foamed alumina particles mentioned above, Example 2 was selected for subsequent experiments. Example 8

[0145] The preparation method of modified polyurethane acrylic resin is as follows, in parts by weight:

[0146] Take 5 parts of hydroxyl-terminated polydimethylsiloxane, 4.5 parts of pentaerythritol triacrylate, 0.1 parts of dibutyltin dilaurate and 0.2 parts of p-hydroxyanisole, mix them, introduce N2, and stir until uniform;

[0147] Heat to 80℃ and begin adding 100 parts of isophorone diisocyanate dropwise, react for 4 hours;

[0148] Adding pentaerythritol triacrylate to neutralize unreacted isocyanate groups yields the modified polyurethane acrylic resin. Example 9

[0149] A method for preparing an ultra-wear-resistant and scratch-resistant UV coating includes the following steps: mixing 150 parts of modified polyurethane acrylic resin, 15 parts of HDDA, 15 parts of DPHA, 6 parts of a mixture of benzophenone and hydroxycyclohexylphenyl ketone, 8 parts of BYK331 leveling agent and 0.5 parts of chitosan evenly, then adding 3 parts of pigment-loaded foamed alumina particles, and stirring again until evenly mixed. Example 10

[0150] A method for preparing an ultra-wear-resistant and scratch-resistant UV coating includes the following steps: mixing 150 parts of modified polyurethane acrylic resin, 15 parts of HDDA, 15 parts of DPHA, 6 parts of a mixture of benzophenone and hydroxycyclohexylphenyl ketone, 8 parts of BYK331 leveling agent and 0.5 parts of chitosan evenly, then adding 7 parts of pigment-loaded foamed alumina particles, and stirring again until evenly mixed. Example 11

[0151] A method for preparing an ultra-wear-resistant and scratch-resistant UV coating includes the following steps: mixing 150 parts of modified polyurethane acrylic resin, 15 parts of HDDA, 15 parts of DPHA, 6 parts of a mixture of benzophenone and hydroxycyclohexylphenyl ketone, 8 parts of BYK331 leveling agent and 0.5 parts of chitosan evenly, then adding 10 parts of pigment-loaded foamed alumina particles, and stirring again until evenly mixed. Comparative Example 4

[0152] The difference between this embodiment and Embodiment 10 is that it uses pigment-loaded foamed alumina particles as in Comparative Example 1. Comparative Example 5

[0153] The difference between this embodiment and Embodiment 10 is that it uses pigment-loaded foamed alumina particles as in Comparative Example 2. Comparative Example 6

[0154] The difference between this embodiment and Embodiment 10 is that it uses pigment-loaded foamed alumina particles as in Comparative Example 3. Comparative Example 7

[0155] The difference between this embodiment and Embodiment 10 is that it uses unmodified conventional polyurethane acrylic resin. Comparative Example 8

[0156] The difference between this embodiment and Embodiment 10 is that pigment-loaded foamed alumina particles are not used; pigments are added directly.

[0157] According to the above embodiments and in combination with the above preparation method, an ultra-wear-resistant and scratch-resistant UV coating was obtained and applied to the treated wood board. After UV curing, a coating with a thickness of 25μm was formed, and conventional performance tests (substrate adhesion (cross-cut), color, coating hardness), wear resistance and Vickers hardness were performed.

[0158] The conventional properties of the coating were tested using standard coating testing methods.

[0159] The Vickers hardness of the coating was tested using a hardness tester with an applied load of 0.0981 N, and the measured value was the hardness value (Hv).

[0160] The abrasion resistance of the coating was tested using a surface abrasion tester. The test conditions were: 294 N applied load, 600# abrasive paper, 4800 abrasion cycles, and abrasion marks of 30 mm × 12 mm. The wear rate was calculated and the color change was observed.

[0161] Performance parameters are shown in Table 2:

[0162] Table 2

[0163] index Substrate adhesion (cross-cut adhesion) Color Vickers hardness Hv (MPa) Wear rate (%) Color change Example 9 5B uniform 96.3 0.71 No change Example 10 5B uniform 121.6 0.46 No change Example 11 5B uniform 127.2 0.42 No change Comparative Example 4 5B uniform 115.8 0.55 Slight changes visible to the naked eye Comparative Example 5 5B uniform 119.4 0.52 Slight changes visible to the naked eye Comparative Example 6 5B uniform 121.9 0.48 Changes are visible to the naked eye Comparative Example 7 4B uniform 117.3 0.69 Changes are visible to the naked eye Comparative Example 8 5B Uneven 83.6 0.97 Visible changes

Claims

1. A super wear-resistant and scratch-resistant UV coating, characterized in that, By weight, it includes the following ingredients: 100-150 parts of modified polyurethane acrylic resin 20-40 parts of reactive diluent 4-6 parts of photoinitiator 3-10 parts of pigment-loaded foamed alumina particles BYK 331 leveling agent 3-10 parts Additives: 0.5-2 parts; The particle size of the pigment-loaded alumina foam is 10-100 μm, and the porosity of the alumina foam is 80-97%. The method for preparing the pigment-loaded foamed alumina particles is as follows: Step 1: Soak polyurethane foam with a pore size of 100 PPI in 10-20% NaOH solution for 2-3 hours, then soak it in a constant temperature water bath at 60℃ for 3 hours. Repeatedly rub to remove the intermesh membrane, rinse with water to obtain the treated polyurethane foam. Step 2: Take 50-80 parts of nano alumina, 5-8 parts of mesoporous alumina fiber, 3-6 parts of silicon carbide hollow microspheres, 3-5 parts of magnesium oxide, 10-15 parts of silicon micro powder and 2-5 parts of nano zirconium oxide, mix and stir evenly to obtain a mixed component, add 35-50% aluminum dihydrogen phosphate solution to form a slurry, and let the slurry stand for 12 hours; Step 3: Place the treated polyurethane foam in the slurry, repeatedly impregnate and squeeze to remove air from the polyurethane foam. After the slurry is fully impregnated into the polyurethane foam and evenly adsorbed onto the polyurethane foam, squeeze the saturated polyurethane foam to squeeze out the excess slurry to obtain the raw blank. Step 4: After drying the green blank at 80℃, transfer it to a high-temperature box-type resistance furnace for sintering. The temperature is increased to 600℃ at a heating rate of 0.5℃ / min and held for 2 hours. Then, the temperature is increased to 1200℃ at a heating rate of 0.3℃ / min and held for 10 hours to obtain foamed alumina. Step 5: Clean the foamed alumina, dry it, crush it and sieve it to obtain foamed alumina granules; Step 6: Take 6 parts of foamed alumina granules, add 100 parts of water, add citric acid for modification, then add 2 parts of organic pigment, and keep at 70℃ for 1-2 hours. Step 7: Add 6 parts of silane coupling agent and 20 parts of 95% ethanol, and react at 70°C for 1-2 hours; Step 8: Add 1.2-1.5 parts of methyl methacrylate, 20 parts of 95% ethanol and ammonium persulfate, and react for 2-3 hours; Step 9: After filtering and drying, wash with 95% ethanol and dry to obtain pigment-loaded foamed alumina particles.

2. The ultra-wear-resistant and scratch-resistant UV coating according to claim 1, characterized in that: The modified polyurethane acrylic resin is prepared as follows, in parts by weight: (1) Take 5 parts of hydroxyl-terminated polydimethylsiloxane, 4.5 parts of pentaerythritol triacrylate, 0.1 parts of dibutyltin dilaurate and 0.2 parts of p-hydroxyanisole, mix them, introduce N2, and stir until uniform; (2) Heat to 80℃ and start adding 100 parts of isophorone diisocyanate dropwise, react for 3-4 hours; (3) Add pentaerythritol triacrylate to neutralize the unreacted isocyanate groups to obtain modified polyurethane acrylic resin.

3. The ultra-wear-resistant and scratch-resistant UV coating according to claim 1, characterized in that: The reactive diluent is a complex of HDDA and DPHA in a ratio of 1:(1-1.5).

4. The ultra-wear-resistant and scratch-resistant UV coating according to claim 1, characterized in that: The photoinitiator is a mixture of benzophenone and hydroxycyclohexylphenyl ketone, or one or more of acylphosphoxides.

5. The ultra-wear-resistant and scratch-resistant UV coating according to claim 1, characterized in that: The nano-alumina particles have a diameter of 30-100 nm, the silicon carbide hollow microspheres have a diameter of 400-580 nm, the magnesium oxide particles have a diameter of 260-500 nm, the silicon micropowder particles have a diameter of 0.5-2 μm, and the nano-zirconia particles have a diameter of 30-80 nm.

6. The ultra-wear-resistant and scratch-resistant UV coating according to claim 1, characterized in that: The mesoporous alumina fibers have mesopores of 2-4 nm on their surface, with an average specific surface area of ​​322 m². 2 / g, fiber diameter is 200-300nm, and length is 7-10μm.

7. The ultra-wear-resistant and scratch-resistant UV coating according to claim 1, characterized in that: The mass of the aluminum dihydrogen phosphate solution is 20-25% of the mixed components.

8. The ultra-wear-resistant and scratch-resistant UV coating according to claim 1, characterized in that: The additive is any one or a combination of two or more of the following: defoamer, formaldehyde removal additive, and antibacterial additive.

9. A method for preparing an ultra-wear-resistant and scratch-resistant UV coating according to any one of claims 1-8, characterized in that: Includes the following steps: After thoroughly mixing the modified polyurethane acrylic resin, reactive diluent, photoinitiator, BYK 331 leveling agent, and additives, add the pigment-loaded foamed alumina particles and stir again until homogeneous.