A highly oil- and water-resistant fluorine-containing composition and its application in coatings

Abstract

The present invention relates to the technical field of coating preparation, and particularly relates to a highly oil- and water-proof fluorine-containing composition and its application in coatings. By weight, the fluorine-containing composition comprises the following chemical components: 70-80 parts of a resin mixture, 2-5 parts of a diisocyanate, 5-8 parts of a modified titanium dioxide filler, and 10-15 parts of modified glass flakes. The resin mixture comprises a fluorinated hydroxyl acrylate resin and a polyurethane acrylate, and the mass ratio of the fluorinated hydroxyl acrylate resin to the polyurethane acrylate is 3-5:1. The resin mixture, the modified titanium dioxide filler, and the modified glass flakes form a stable composite structure through chemical bonding and physical action, ultimately enabling the fluorine-containing composition to exhibit excellent water- and oil-proof properties and good mechanical strength.

Description

Technical Field

[0001] The invention relates to the technical field of coating preparation, and in particular to a highly oil-proof and waterproof fluorine-containing composition and application thereof in coatings. Background Art

[0002] Superhydrophobicity is a surface property of a material, which is reflected in the fact that droplets are not easy to spread, adhere and remain on the surface of the material. This property can be applied to many engineering and technical fields such as self-cleaning, anti-corrosion, hull drag reduction, anti-icing, etc., and has broad application prospects. The hydrophobicity of the material surface is mainly determined by the surface atomic properties and microscopic morphology. Most natural superhydrophobic materials have two characteristics: low interfacial atomic surface energy and micron and nanometer dual-scale rough surface morphology. The contact angle is one of the important criteria for measuring the hydrophobicity of the material surface. It is generally believed that when the contact angle is greater than 150°, the material surface is superhydrophobic.

[0003] Existing super-hydrophobic surface preparation technology such as sol-gel method, vapor deposition method, etching method, template method, anodization method, phase separation, etc., has a complex preparation process and demanding conditions. Super-hydrophobic coating is increasingly used in super-hydrophobic field because of its unique advantages such as simple preparation process, convenient application, wide range of applications. However, existing super-hydrophobic coatings on the market generally have mechanical properties such as strength and substrate adhesion, anti-liquid flow penetration, poor corrosion resistance, etc., which are specifically embodied in coating surface special morphology, easy to fall off, damage, such as encountering high-speed liquid flow impact, prone to penetration damage, easily eroded by acid (base) substances under special environment, and then lose super-hydrophobic performance, and these technical problems make super-hydrophobic coating difficult to large-scale application so far. For example, patent publication number CN201410456523.7 relates to a zinc-aluminum composite coating, including two components A and B. Component A is a two-component composition mixed by components A and B. Component A in component A includes polyarylethersulfoneketone modified resin, silicon carbide micropowder, graphite fluoride and coupling agent component, component B in component A includes silicon carbide, aluminum oxide, solvent, 0.8-6 parts of zinc oxide and epoxy resin component, and component B includes curing agent, defoaming agent and leveling agent. The zinc-aluminum composite coating of the invention has excellent properties such as good wear resistance, mechanical properties, high temperature resistance, flame retardancy, radiation resistance, hydrolysis resistance, insulation stability, etc. The construction process of the zinc-aluminum composite coating is simple and the cost is low, so that the bonding between the zinc-aluminum composite coating and the steel body is strong, and the steel body is well protected from corrosion. However, the main resin of this composite coating is modified with polyarylethersulfoneketone, which has no weather resistance and is prone to yellowing and powdering when exposed to ultraviolet rays or sunlight; and this composite coating is relatively hydrophilic, resulting in poor anti-corrosion performance of the composite coating. Summary of the invention

[0004] In view of this, the present invention provides a highly oil- and water-resistant fluorine-containing composition and its application in coatings to solve the problem in the prior art that the oil- and water-proof performance of coatings is poor, resulting in reduced anti-corrosion performance.

[0005] The technical solution of the present invention is realized as follows: The present invention provides a highly oil- and water-resistant fluorine-containing composition. By weight, the fluorine-containing composition includes the following chemical components: 70-80 parts of a resin mixture, 2-5 parts of a diisocyanate, 5-8 parts of a modified titanium dioxide filler, and 10-15 parts of modified glass flakes. The resin mixture includes a fluorinated hydroxyacrylate resin and a polyurethane acrylate.

[0006] Based on the above technical solution, preferably, in the resin mixture, the mass ratio of the fluorinated hydroxyacrylate resin to the polyurethane acrylate is 3-5:1.

[0007] Specifically, the fluorinated hydroxyacrylate resin provides the oil- and water-proof function through its fluorine-containing groups to achieve low surface energy characteristics; the polyurethane acrylate provides excellent mechanical strength, flexibility, and substrate adhesion; the modified titanium dioxide filler forms a strong interfacial bond with the resin matrix through multiple surface modifications. The hydrophobic groups on its surface and the fluorine-containing groups in the resin act synergistically to enhance the overall water- and oil-proof effect; the modified glass flakes form an orderly arranged layered structure in the coating and are tightly combined with the resin matrix. The grafted multifunctional groups on its surface not only enhance the compatibility with the matrix but also improve the overall strength of the coating through entanglement with the resin molecular chains. The layered structure and the resin matrix act synergistically to form an effective anti-permeation barrier.

[0008] Based on the above technical solution, preferably, the preparation method of the modified titanium dioxide filler includes the following steps:

[0009] (1) Disperse titanium dioxide particles in water, then add a sodium silicate solution, stir evenly, add an acid for aging to obtain titanium dioxide coated with silica.

[0010] (2) Disperse the titanium dioxide coated with silica in an ethanol-water mixed solution, add a mercapto silane coupling agent, stir and react. After the reaction is completed, filter, wash, and dry to obtain mercapto-functionalized titanium dioxide.

[0011] (3) Add the mercapto-functionalized titanium dioxide to DMF, then add trifluoromethyl acrylic acid and benzophenone, and carry out a thiol-ene reaction under ultraviolet light to obtain the modified titanium dioxide filler.

[0012] Titanium dioxide has good chemical stability and weather resistance, which can improve the overall durability of the coating. At the same time, it has certain photocatalytic activity itself, which can improve the self-cleaning performance of the coating. In step (1), a silica coating layer is formed on the surface of titanium dioxide through the hydrolysis of sodium silicate to provide active sites. At the same time, the silica layer can reduce the photocatalytic activity of titanium dioxide and avoid the photocatalytic degradation of the resin. In step (2), a mercapto group is introduced through the chemical bonding of a mercapto silane coupling agent with the surface silica layer. In step (3), a hydrophobic group is introduced through the reaction of the mercapto group with trifluoromethyl acrylic acid. This not only improves the dispersion of the filler in the resin matrix but also enhances the overall waterproof and oil-proof performance of the coating through the introduction of surface hydrophobic groups, while improving the interfacial bonding force between the filler and the resin matrix.

[0013] On the basis of the above technical solutions, preferably, in step (1), the mass ratio of titanium dioxide to sodium silicate is 1:0.4 - 0.8, the aging temperature is 70 - 90 °C, and the aging time is 3 - 5 h.

[0014] On the basis of the above technical solutions, preferably, the particle size of the titanium dioxide particles is 20 - 1000 nm, the concentration of the sodium silicate solution is 25 - 30 wt%, the modulus of the sodium silicate solution is 2.1 - 2.4, the acid is preferably a sulfuric acid solution or a hydrochloric acid solution, the acid concentration is 1 - 2 mol / L, and the pH value of the mixed slurry is adjusted to 5 - 6 by adding the acid.

[0015] On the basis of the above technical solutions, preferably, in step (2), the mass ratio of the mercapto silane coupling agent to the titanium dioxide coated with silica is 1:0.8 - 1.5, the mercapto silane coupling agent is 3-mercaptopropyltrimethoxysilane, the heating reaction temperature is 70 - 80 °C, the heating reaction time is 2 - 4 h, and the volume ratio of ethanol to water in the ethanol-water mixed solution is 20 - 30:1.

[0016] On the basis of the above technical solutions, preferably, in step (3), the mass ratio of mercapto-functionalized titanium dioxide, trifluoromethyl acrylic acid, and benzophenone is 10 - 20:1.5 - 2.5:0.1 - 0.3, the temperature of the mercapto-functionalization reaction is 40 - 50 °C, and the reaction time is 20 - 30 min.

[0017] On the basis of the above technical solutions, preferably, the preparation method of the modified glass flakes is as follows:

[0018] (a) Mix the glass flakes with absolute ethanol and stir for 20 - 30 min, then add an ethanol solution of γ-aminopropyltrimethoxysilane and stir at 55 - 65 °C for 1 - 3 h to obtain amino-functionalized glass flakes;

[0019] (b) Add the aminated glass flakes into toluene, add acryloyl chloride under nitrogen protection, stir and react for 10 - 20 min, then add triethylamine, and stir and react at room temperature for 16 - 20 h to obtain acylated glass flakes;

[0020] (c) Disperse the acylated glass flakes in DMF, add acrylic acid monomer, perfluorooctylethyl acrylate and 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate, stir and mix evenly, then add azobisisobutyronitrile, and carry out graft copolymerization reaction under ultraviolet light irradiation at room temperature for 2 - 3 h to obtain modified glass flakes.

[0021] Specifically, first construct reactive sites on the surface through amination, then introduce polymerizable double bonds through acylation, and finally introduce various functional groups through graft copolymerization. Among them, the acrylic acid monomer introduces carboxyl groups to provide reactive sites, perfluorooctylethyl acrylate introduces hydrophobic and oil-proof groups, and 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate provides ultraviolet protection function. Through multiple modifications, not only the compatibility between the glass flakes and the resin matrix is improved, but also multiple functions such as hydrophobic, oil-proof and anti-ultraviolet are imparted, so that the modified glass flakes can play a synergistic role of strengthening and protecting in the coating.

[0022] Based on the above technical solutions, preferably, in step (a), the mass ratio of the glass flakes to γ-aminopropyltrimethoxysilane is 100:10 - 15, and the mass concentration of the ethanol solution of γ-aminopropyltrimethoxysilane is 5 - 7%; in step (b), the mass ratio of the aminated glass flakes, acryloyl chloride and triethylamine is 100:8 - 12:12 - 15.

[0023] Based on the above technical solutions, preferably, in step (c), the mass ratio of the acylated glass flakes to the total mass of the acrylic acid monomer, perfluorooctylethyl acrylate and 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate is 100:20 - 25; the mass ratio of the acrylic acid monomer, perfluorooctylethyl acrylate and 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate is 1:2:1; the addition amount of the azobisisobutyronitrile is 2 - 3% of the total mass of the acrylic acid monomer, perfluorooctylethyl acrylate and 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate.

[0024] Based on the above technical solutions, preferably, the diisocyanate is isophorone diisocyanate or toluene diisocyanate.

[0025] The present invention provides a preparation method of a highly oil-proof and waterproof fluorine-containing composition as described in any one of the above, comprising the following steps:

[0026] S1. Mix and disperse fluorinated hydroxy acrylic resin and polyurethane acrylate in ethyl acetate at a mass ratio of 3 - 5:1, and stir evenly to obtain a resin mixture;

[0027] S2. Add the modified titanium dioxide filler and the modified glass flakes into the resin mixture in sequence, stir and disperse at 35 - 45 °C for 30 - 60 min; then add diisocyanate, stir evenly for 10 - 20 min, and finally adjust the solid content to 30 - 35% to obtain a highly oil - and water - resistant fluorine - containing composition.

[0028] Specifically, the - NCO groups in the diisocyanate molecules can react with the hydroxyl groups in the resin body, the carboxyl groups on the surface of the modified titanium dioxide filler, and the carboxyl groups on the surface of the modified glass flakes. Thus, the modified titanium dioxide filler and the modified glass flakes are firmly fixed in the network structure through chemical bonding, enhancing the interfacial bonding force between the components and improving the overall mechanical strength and durability of the fluorine - resistant composition.

[0029] The present invention provides an application of a highly oil - and water - resistant fluorine - containing composition as described in any one of the above in coatings. By weight, it includes 60 - 70 parts of the fluorine - containing composition, 0.5 - 1.0 part of a leveling agent, and 15 - 20 parts of ethyl acetate.

[0030] A highly oil - and water - resistant fluorine - containing composition of the present invention and its application in coatings have the following beneficial effects compared with the prior art:

[0031] (1) The fluorinated hydroxy acrylic resin provides basic water - and oil - resistant properties, and the polyurethane acrylate provides mechanical strength and toughness. The two are compounded to achieve complementary performance; the modified titanium dioxide filler improves the compatibility and interfacial bonding force with the resin matrix through multiple surface modifications, and at the same time enhances the overall protection performance of the coating; the modified glass flakes form an ordered layered structure in the coating, significantly improving the anti - permeability and weather resistance of the coating; the diisocyanate forms a dense three - dimensional network structure through cross - linking reactions with the hydroxyl groups in the resin molecules and the active groups on the surface of the filler, further enhancing the overall performance of the coating; each component forms a stable composite structure through chemical bonding and physical interactions, and finally the fluorine - containing composition exhibits excellent water - and oil - resistant properties and good mechanical strength;

[0032] (2) A silica layer is formed by coating with sodium silicate, and then a mercapto silane coupling agent is introduced for the first-step surface modification. Finally, fluorine groups are further introduced through a thiol-ene reaction. This layer-by-layer construction strategy forms a functionalized interfacial layer with a gradient transition on the filler surface. Among them, titanium dioxide, as the core filler, has excellent weather resistance and light stability. The coated silica layer not only provides abundant surface hydroxyl groups for subsequent modification but also effectively prevents the direct contact between titanium dioxide and the resin matrix, avoiding photocatalytic degradation. The mercapto groups provide active sites for chemical bonding with the resin matrix, and the fluorine-containing groups endow the filler with excellent hydrophobic properties, significantly improving the dispersion stability of the filler and its compatibility with the resin matrix, thereby increasing the water and oil resistance of the resin mixture.

[0033] (3) In the modified glass flakes, amino modification is first carried out through γ-aminopropyltrimethoxysilane to form a uniform amino active layer on the glass flake surface. Subsequently, acyl modification is carried out through acryloyl chloride to convert the surface amino groups into amide structures containing unsaturated double bonds, providing reaction sites for further functionalization. Finally, through a UV-initiated graft copolymerization reaction, acrylic acid skeletons, perfluorooctyl hydrophobic groups, and benzotriazole UV protection groups are simultaneously introduced onto the glass flake surface, enabling the modified glass flakes to not only form an effective layered barrier structure in the coating but also significantly enhance the anti-permeability, hydrophobicity, and weather resistance of the coating through the synergistic effect of surface functional groups. Detailed implementation manners

[0034] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0035] It should be noted that

[0036] The polyurethane acrylate is purchased from Risheng New Materials Co., Ltd., with the product model number RU-6380H and a viscosity of 1500 - 3000 cps / 25°C; the titanium dioxide is purchased from Shanghai Yunfu Nano Technology Co., Ltd.

[0037] In the embodiments of the present application, the fluorinated hydroxyacrylate resin is prepared by the following method. Specifically, its preparation method is:

[0038] 5% to 8% by mass of methyl methacrylate (MMA), 35% to 50% by mass of n-butyl acrylate (BA), 3.5% to 5.5% by mass of hydroxyethyl methacrylate (HEMA), 30% to 45% by mass of methacrylic acid (MAA), 15% to 20% by mass of dodecafluoroheptyl methacrylate (G04) monomer, 1.5% to 2% by mass of mercaptoethanol as a chain transfer agent, and 1% to 1.5% by mass of tert-butyl peroxide (TBPB) as an initiator are mixed to obtain a mixed solution;

[0039] Using tert-butyl carbonate (E10P) and propylene glycol butyl ether in a mass ratio of 1:1 as a solvent, wherein the mass of the solvent is 15% to 25% of the total mass of the monomers;

[0040] Add solvent to the reaction container, introduce nitrogen, stir and heat to 140-160°C, add 10-15% of the mixed solution of monomer, chain transfer agent and initiator at one time, react for 30 minutes, add the remaining mixed solution dropwise at a uniform speed within 6-7 hours, keep warm for 0.5 hours, then add 0.5% of initiator, keep warm for 1-1.5 hours to terminate the polymerization, cool to 70-90°C, neutralize with N,N-dimethylethanolamine, add water and disperse at high speed to obtain fluorinated hydroxy acrylic resin.

[0041] Example 1

[0042] This embodiment discloses a highly oil-proof and waterproof fluorine-containing composition and a preparation method thereof, comprising the following steps:

[0043] S1, 80g of fluorinated hydroxyl acrylic resin and 20g of polyurethane acrylate were mixed to obtain a resin mixture, and then 75g of the resin mixture was dispersed in 700ml of ethyl acetate and stirred to obtain a resin mixture;

[0044] S2. Add 6.5 g of modified titanium dioxide filler and 13 g of modified glass flakes to the resin mixture in sequence, and stir and disperse at 40°C for 45 min; then add 3.5 g of diisocyanate, stir evenly for 15 min, and finally adjust the solid content to 30-35% to obtain a highly oil-proof and waterproof fluorine-containing composition.

[0045] Wherein, the preparation method of modified titanium dioxide filler is as follows:

[0046] (1) 40 g of titanium dioxide particles with a particle size of 500 nm were dispersed in 100 ml of water, and then 24 g of sodium silicate solution (the concentration of the sodium silicate solution was 30 wt%) was added, and the mixture was stirred evenly. A 1.5 mol / L sulfuric acid solution was added to adjust the pH to 5-6, and the mixture was aged at 80° C. for 4 h, and then filtered, washed, and dried in sequence to obtain titanium dioxide coated with silicon dioxide;

[0047] (2) Disperse 10 g of 3-mercaptopropyltrimethoxysilane and 12 g of silica-coated titanium dioxide in 150 ml of an ethanol-water mixed solution (the volume ratio of ethanol to water is 25:1), heat and stir the reaction at 75 °C for 3 h, and after the reaction is completed, filter, wash, and dry to obtain mercapto-functionalized titanium dioxide;

[0048] (3) Add 15 g of mercapto-functionalized titanium dioxide to 150 ml of DMF, then add 2 g of trifluoromethylacrylic acid and 0.2 g of benzophenone, and carry out a thiol-ene reaction under ultraviolet light (ultraviolet light intensity is 550 mW / cm 2 ), the reaction temperature is 45 °C, the reaction time is 25 min, and after the reaction is completed, filter, wash, and dry to obtain modified titanium dioxide filler;

[0049] The preparation method of the modified glass flakes is as follows:

[0050] (1) Mix 10 g of glass flakes with 200 ml of absolute ethanol, ultrasonically stir and disperse for 25 min, then add 1.3 g of γ-aminopropyltrimethoxysilane (γ-aminopropyltrimethoxysilane is prepared as an ethanol solution with a mass concentration of 6%) and stir at 60 °C for 2 h. After the reaction is completed, filter, wash, and dry to obtain amino-functionalized glass flakes;

[0051] (2) Add 10 g of amino-functionalized glass flakes to 100 ml of toluene, ultrasonically disperse for 10 min, add 1.0 g of acryloyl chloride under nitrogen protection, stir the reaction for 15 min, then add 1.35 g of triethylamine, and stir the reaction at room temperature for 18 h. After the reaction is completed, filter, wash, and dry to obtain acylated glass flakes;

[0052] (3) Disperse 10 g of acylated glass flakes in 100 ml of DMF, sequentially add 5.8 g of acrylic acid monomer, 5.8 g of 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate, and 11.5 g of perfluorooctylethyl acrylate, stir and mix evenly, then dissolve 0.6 g of azobisisobutyronitrile in 10 ml of DMF, slowly drop it into the reaction system, and carry out a graft copolymerization reaction under ultraviolet light irradiation (wavelength 365 nm) at room temperature for 2.5 h. After the reaction is completed, filter, wash, and dry to obtain modified glass flakes.

[0053] Example 2

[0054] This example discloses a highly oil- and water-resistant fluorine-containing composition and its preparation method, including the following steps:

[0055] S1. Mix 75 g of fluorinated hydroxy acrylic resin and 25 g of polyurethane acrylate to obtain a resin mixture. Then, take 70 g of the resin mixture and disperse it in 700 ml of ethyl acetate, and stir evenly to obtain the resin mixture;

[0056] S2. Add 5 g of modified titanium dioxide filler and 10 g of modified glass flakes to the resin mixture in sequence, and stir and disperse at 35 °C for 60 min; then add 2 g of diisocyanate, stir evenly for 10 min, and finally adjust the solid content to 30 - 35%, to obtain a highly oil- and water-resistant fluorine-containing composition.

[0057] Among them, the preparation method of the modified titanium dioxide filler is as follows:

[0058] (1) Disperse 40 g of titanium dioxide particles with a particle size of 100 nm into 100 ml of water, then add 16 g of sodium silicate solution (the concentration of sodium silicate solution is 30 wt%), stir evenly, add 1 mol / L sulfuric acid solution to adjust the pH to 5 - 6, age at 70 °C for 5 h, and then filter, wash, and dry in sequence to obtain titanium dioxide coated with silica;

[0059] (2) Disperse 10 g of 3-mercaptopropyltrimethoxysilane and 8 g of titanium dioxide coated with silica in 100 ml of ethanol-water mixed solution (the volume ratio of ethanol to water is 20:1), heat and stir at 70 °C for 4 h, filter, wash, and dry after the reaction is completed to obtain mercapto-functionalized titanium dioxide;

[0060] (3) Add 10 g of mercapto-functionalized titanium dioxide to 100 ml of DMF, then add 1.5 g of trifluoromethylacrylic acid and 0.1 g of benzophenone, and carry out a thiol-ene reaction under ultraviolet light (ultraviolet light intensity is 550 mW / cm 2 ), the reaction temperature is 40 °C, the reaction time is 30 min, filter, wash, and dry after the reaction is completed to obtain the modified titanium dioxide filler;

[0061] The preparation method of the modified glass flakes is as follows:

[0062] (1) Mix 10 g of glass flakes with 200 ml of absolute ethanol, ultrasonically stir and disperse for 20 min, then add 1 g of γ-aminopropyltrimethoxysilane (γ-aminopropyltrimethoxysilane is prepared as an ethanol solution with a mass concentration of 5%) and stir at 55 °C for 3 h. After the reaction is completed, filter, wash, and dry to obtain amino-functionalized glass flakes;

[0063] (2) Add 10 g of aminated glass flakes to 100 ml of toluene, ultrasonically disperse for 10 min, add 0.8 g of acryloyl chloride under nitrogen protection, stir and react for 10 min, then add 1.2 g of triethylamine, stir and react at room temperature for 16 h. After the reaction is completed, filter, wash, and dry to obtain acylated glass flakes;

[0064] (3) Disperse 10 g of acylated glass flakes in 100 ml of DMF, sequentially add 5 g of acrylic acid monomer, 5 g of 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate, and 10 g of perfluorooctylethyl acrylate, stir and mix evenly. Then dissolve 0.4 g of azobisisobutyronitrile in 10 ml of DMF, slowly drop it into the reaction system, and carry out graft copolymerization reaction under ultraviolet light irradiation (wavelength 365 nm) at room temperature for 2 h. After the reaction is completed, filter, wash, and dry to obtain modified glass flakes.

[0065] Example 3

[0066] This example discloses a highly oil- and water-resistant fluorine-containing composition and its preparation method, including the following steps:

[0067] S1. Mix 83 g of fluorinated hydroxyacrylate resin and 17 g of polyurethane acrylate to obtain a resin mixture. Then take 80 g of the resin mixture and disperse it in 700 ml of ethyl acetate, and stir evenly to obtain a resin mixture;

[0068] S2. Sequentially add 8 g of modified titanium dioxide filler and 15 g of modified glass flakes to the resin mixture, stir and disperse at 45 °C for 30 min; then add 5 g of diisocyanate, stir evenly for 20 min, and finally adjust the solid content to 30 - 35% to obtain a highly oil- and water-resistant fluorine-containing composition.

[0069] Among them, the preparation method of the modified titanium dioxide filler is as follows:

[0070] (1) Disperse 40 g of titanium dioxide particles with a particle size of 1000 nm in 100 ml of water, then add 32 g of sodium silicate solution (the concentration of sodium silicate solution is 30 wt%), stir evenly, add 2 mol / L sulfuric acid solution to adjust the pH to 5 - 6, age at 90 °C for 3 h, and then filter, wash, and dry in sequence to obtain titanium dioxide coated with silica;

[0071] (2) Disperse 10 g of 3-mercaptopropyltrimethoxysilane and 15 g of titanium dioxide coated with silica in 200 ml of ethanol-water mixed solution (the volume ratio of ethanol to water is 20:1), heat and stir at 80 °C for 2 h. After the reaction is completed, filter, wash, and dry to obtain mercapto-functionalized titanium dioxide;

[0072] (3) Add 20 g of mercapto-functionalized titanium dioxide to 200 ml of DMF, then add 2.5 g of trifluoromethylacrylic acid and 0.3 g of benzophenone, and carry out a thiol-ene reaction under ultraviolet light (ultraviolet light intensity is 550 mW / cm 2 ), with the reaction temperature being 50 °C and the reaction time being 20 min. After the reaction is completed, filter, wash, and dry to obtain modified titanium dioxide filler;

[0073] The preparation method of the modified glass flakes is as follows:

[0074] (1) Mix 10 g of glass flakes with 200 ml of absolute ethanol, ultrasonically stir and disperse for 20 - 30 min, then add 1.5 g of γ-aminopropyltrimethoxysilane (γ-aminopropyltrimethoxysilane is prepared as an ethanol solution with a mass concentration of 5 - 7% for use), stir at 65 °C for 1 h. After the reaction is completed, filter, wash, and dry to obtain amino-functionalized glass flakes;

[0075] (2) Add 10 g of amino-functionalized glass flakes to 100 ml of toluene, ultrasonically disperse for 10 min, add 1.2 g of acryloyl chloride under nitrogen protection, stir and react for 20 min, then add 1.5 g of triethylamine, and stir and react at room temperature for 20 h. After the reaction is completed, filter, wash, and dry to obtain acyl-functionalized glass flakes;

[0076] (3) Disperse 10 g of acyl-functionalized glass flakes in 100 ml of DMF, sequentially add 6.25 g of acrylic acid monomer, 6.25 g of 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate, and 12.5 g of perfluorooctylethyl acrylate, stir and mix evenly. Then dissolve 0.75 g of azobisisobutyronitrile in 10 ml of DMF, slowly drop it into the reaction system, and carry out a graft copolymerization reaction under ultraviolet light irradiation (wavelength 365 nm) at room temperature for 3 h. After the reaction is completed, filter, wash, and dry to obtain modified glass flakes.

[0077] Example 4

[0078] This example discloses a highly oil- and water-resistant fluorine-containing composition and its preparation method, including the following steps:

[0079] S1. Mix 77 g of fluorinated hydroxy acrylic resin and 23 g of polyurethane acrylate to obtain a resin mixture, and then take 73 g of the resin mixture and disperse it in 700 ml of ethyl acetate, stir evenly to obtain a resin mixture;

[0080] S2. Add 6 g of modified titanium dioxide filler and 11.5 g of modified glass flakes into the resin mixture in sequence, stir and disperse for 50 min at 40 °C; then add 3 g of diisocyanate, stir evenly for 18 min, and finally adjust the solid content to 30 - 35%, obtaining a highly oil- and water-resistant fluorine-containing composition.

[0081] Among them, the preparation method of the modified titanium dioxide filler is as follows:

[0082] (1) Disperse 40 g of titanium dioxide particles with a particle size of 800 nm into 100 ml of water, then add 20 g of sodium silicate solution (the concentration of the sodium silicate solution is 30 wt%), stir evenly, add 1.5 mol / L sulfuric acid solution to adjust the pH to 5 - 6, age at 75 °C for 4.5 h, and then filter, wash, and dry in sequence to obtain titanium dioxide coated with silica;

[0083] (2) Disperse 10 g of 3-mercaptopropyltrimethoxysilane and 10 g of titanium dioxide coated with silica in 150 ml of ethanol-water mixed solution (the volume ratio of ethanol to water is 25:1), heat and stir at 75 °C for 2.5 h, filter, wash, and dry after the reaction is completed to obtain mercapto-functionalized titanium dioxide;

[0084] (3) Add 12 g of mercapto-functionalized titanium dioxide into 120 ml of DMF, then add 1.8 g of trifluoromethylacrylic acid and 0.25 g of benzophenone, and carry out a thiol-ene reaction under ultraviolet light (the ultraviolet light intensity is 550 mW / cm 2 ), the reaction temperature is 45 °C, the reaction time is 22 min, filter, wash, and dry after the reaction is completed to obtain the modified titanium dioxide filler;

[0085] The preparation method of the modified glass flakes is as follows:

[0086] (1) Mix 10 g of glass flakes with 200 ml of absolute ethanol, stir and disperse ultrasonically for 25 min, then add 1.2 g of γ-aminopropyltrimethoxysilane (γ-aminopropyltrimethoxysilane is prepared as an ethanol solution with a mass concentration of 6%) and stir at 60 °C for 2.5 h. After the reaction is completed, filter, wash, and dry to obtain amino-functionalized glass flakes;

[0087] (2) Add 10 g of amino-functionalized glass flakes into 100 ml of toluene, disperse ultrasonically for 10 min, add 1.1 g of acryloyl chloride under nitrogen protection, stir for 15 min, then add 1.3 g of triethylamine, and stir at room temperature for 19 h. After the reaction is completed, filter, wash, and dry to obtain acylated glass flakes;

[0088] (3) Disperse 10 g of acylated glass flakes in 100 ml of DMF. Sequentially add 6 g of acrylic monomer, 6 g of 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate, and 11 g of perfluorooctylethyl acrylate. Stir and mix evenly. Then dissolve 0.6 g of azobisisobutyronitrile in 10 ml of DMF, slowly add it dropwise to the reaction system, and carry out graft copolymerization reaction under ultraviolet light irradiation (wavelength 365 nm) at room temperature for 2.5 h. After the reaction is completed, filter, wash, and dry to obtain modified glass flakes.

[0089] Comparative Example 1

[0090] This comparative example discloses a highly oil- and water-proof fluorine-containing composition and its preparation method, including the following steps:

[0091] S1. Mix 80 g of fluorinated hydroxyacrylic resin and 20 g of polyurethane acrylate to obtain a resin mixture. Then take 75 g of the resin mixture and disperse it in 700 ml of ethyl acetate, and stir evenly to obtain a resin mixture;

[0092] S2. Sequentially add 6.5 g of modified titanium dioxide filler and 13 g of modified glass flakes to the resin mixture, and stir and disperse at 40 °C for 45 min; then add 3.5 g of diisocyanate, stir evenly for 15 min, and finally adjust the solid content to 30 - 35% to obtain a highly oil- and water-proof fluorine-containing composition.

[0093] Among them, the preparation method of the modified titanium dioxide filler is as follows:

[0094] (1) Disperse 40 g of titanium dioxide particles with a particle size of 500 nm in 100 ml of water, then add 24 g of sodium silicate solution (the concentration of sodium silicate solution is 30 wt%), stir evenly, add 1.5 mol / L sulfuric acid solution to adjust the pH to 5 - 6, age at 80 °C for 4 h, and then filter, wash, and dry in sequence to obtain titanium dioxide coated with silica, which is the modified titanium dioxide filler;

[0095] The preparation method of the modified glass flakes is as follows:

[0096] (1) Mix 10 g of glass flakes with 200 ml of absolute ethanol, stir and disperse ultrasonically for 25 min, then add 1.3 g of γ-aminopropyltrimethoxysilane (γ-aminopropyltrimethoxysilane is prepared as an ethanol solution with a mass concentration of 6%) and stir at 60 °C for 2 h. After the reaction is completed, filter, wash, and dry to obtain amino-functionalized glass flakes;

[0097] (2) Add 10 g of aminated glass flakes to 100 ml of toluene, ultrasonically disperse for 10 min, add 1.0 g of acryloyl chloride under nitrogen protection, stir and react for 15 min, then add 1.35 g of triethylamine, stir and react at room temperature for 18 h. After the reaction is completed, filter, wash, and dry to obtain acylated glass flakes;

[0098] (3) Disperse 10 g of acylated glass flakes in 100 ml of DMF, sequentially add 5.8 g of acrylic acid monomer, 5.8 g of 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl] ethyl methacrylate, and 11.5 g of perfluorooctylethyl acrylate, stir and mix evenly. Then dissolve 0.6 g of azobisisobutyronitrile in 10 ml of DMF, slowly drop it into the reaction system, and carry out graft copolymerization reaction under ultraviolet light irradiation (wavelength 365 nm) at room temperature for 2.5 h. After the reaction is completed, filter, wash, and dry to obtain modified glass flakes.

[0099] Comparative Example 2

[0100] This example discloses a highly oil- and water-resistant fluorine-containing composition and its preparation method, including the following steps:

[0101] S1. Mix 80 g of fluorinated hydroxyacrylate resin and 20 g of polyurethane acrylate to obtain a resin mixture. Then take 75 g of the resin mixture and disperse it in 700 ml of ethyl acetate, stir evenly to obtain a resin mixture;

[0102] S2. Add 6.5 g of modified titanium dioxide filler and 13 g of modified glass flakes to the resin mixture in sequence, stir and disperse at 40 °C for 45 min; then add 3.5 g of diisocyanate, stir evenly for 15 min, and finally adjust the solid content to 30-35% to obtain a highly oil- and water-resistant fluorine-containing composition.

[0103] Among them, the preparation method of the modified titanium dioxide filler is as follows:

[0104] (1) Disperse 40 g of titanium dioxide particles with a particle size of 500 nm in 100 ml of water, then add 24 g of sodium silicate solution (the concentration of sodium silicate solution is 30 wt%), stir evenly, add 1.5 mol / L sulfuric acid solution to adjust the pH to 5-6, age at 80 °C for 4 h, and then filter, wash, and dry in sequence to obtain titanium dioxide coated with silica;

[0105] (2) Disperse 10 g of 3-mercaptopropyltrimethoxysilane and 12 g of titanium dioxide coated with silica in 150 ml of ethanol-water mixed solution (the volume ratio of ethanol to water is 25:1), heat and stir at 75 °C for 3 h. After the reaction is completed, filter, wash, and dry to obtain mercapto-functionalized titanium dioxide;

[0106] (3) Add 15 g of mercapto-functionalized titanium dioxide to 150 ml of DMF, then add 2 g of trifluoromethylacrylic acid and 0.2 g of benzophenone. Under the action of ultraviolet light (ultraviolet light intensity is 550 mW / cm 2 ), carry out a thiol-ene reaction at a reaction temperature of 45 °C for 25 min. After the reaction is completed, filter, wash, and dry to obtain modified titanium dioxide filler;

[0107] The preparation method of the modified glass flakes is as follows:

[0108] (1) Mix 10 g of glass flakes with 200 ml of absolute ethanol, ultrasonically stir and disperse for 25 min, then add 1.3 g of γ-aminopropyltrimethoxysilane (γ-aminopropyltrimethoxysilane is prepared as an ethanol solution with a mass concentration of 6%) and stir at 60 °C for 2 h. After the reaction is completed, filter, wash, and dry to obtain amino-functionalized glass flakes.

[0109] Comparative Example 3

[0110] This example discloses a highly oil- and water-resistant fluorine-containing composition and its preparation method, including the following steps:

[0111] S1. Mix 80 g of fluorinated hydroxyacrylate resin and 20 g of polyurethane acrylate to obtain a resin mixture. Then take 75 g of the resin mixture and disperse it in 700 ml of ethyl acetate, and stir evenly to obtain a resin mixture;

[0112] S2. Add 6.5 g of modified titanium dioxide filler and 13 g of modified glass flakes to the resin mixture in sequence, and stir and disperse at 40 °C for 45 min; then add 3.5 g of diisocyanate and stir evenly for 15 min. Finally, adjust the solid content to 30 - 35% to obtain a highly oil- and water-resistant fluorine-containing composition.

[0113] Among them, the preparation method of the modified titanium dioxide filler is as follows:

[0114] (1) Disperse 40 g of titanium dioxide particles with a particle size of 500 nm into 100 ml of water, then add 24 g of sodium silicate solution (sodium silicate solution concentration is 30 wt%), stir evenly, add 1.5 mol / L sulfuric acid solution to adjust the pH to 5 - 6, and age at 80 °C for 4 h. Then filter, wash, and dry in sequence to obtain titanium dioxide coated with silica;

[0115] (2) Disperse 10 g of 3-mercaptopropyltrimethoxysilane and 12 g of titanium dioxide coated with silica in 150 ml of ethanol-water mixed solution (volume ratio of ethanol to water is 25:1), heat and stir at 75 °C for 3 h. After the reaction is completed, filter, wash, and dry to obtain mercapto-functionalized titanium dioxide;

[0116] (3) Add 15 g of mercapto-functionalized titanium dioxide to 150 ml of DMF, then add 2 g of trifluoromethylacrylic acid and 0.2 g of benzophenone. Under the action of ultraviolet light (ultraviolet light intensity is 550 mW / cm 2 ), carry out the thiol-ene reaction at a reaction temperature of 45 °C for 25 min. After the reaction is completed, filter, wash, and dry to obtain modified titanium dioxide filler;

[0117] The preparation method of the modified glass flakes is as follows:

[0118] (1) Mix 10 g of glass flakes with 200 ml of absolute ethanol, ultrasonically stir and disperse for 25 min, then add 1.3 g of γ-aminopropyltrimethoxysilane (γ-aminopropyltrimethoxysilane is prepared as an ethanol solution with a mass concentration of 6%) and stir at 60 °C for 2 h. After the reaction is completed, filter, wash, and dry to obtain amino-functionalized glass flakes;

[0119] (2) Add 10 g of amino-functionalized glass flakes to 100 ml of toluene, ultrasonically disperse for 10 min, add 1.0 g of acryloyl chloride under nitrogen protection, stir and react for 15 min, then add 1.35 g of triethylamine and stir and react at room temperature for 18 h. After the reaction is completed, filter, wash, and dry to obtain acyl-functionalized glass flakes;

[0120] (3) Disperse 10 g of acyl-functionalized glass flakes in 100 ml of DMF, add 11.5 g of perfluorooctylethyl acrylate in sequence, stir and mix evenly, then dissolve 0.6 g of azobisisobutyronitrile in 10 ml of DMF, slowly drop it into the reaction system, and carry out graft copolymerization reaction under ultraviolet light irradiation (wavelength 365 nm) at room temperature for 2.5 h. After the reaction is completed, filter, wash, and dry to obtain modified glass flakes.

[0121] Preparation of the coating

[0122] Weigh 65 g of the fluorine-containing composition prepared in the examples and comparative examples, disperse it in 20 g of toluene, stir evenly, add 0.8 g of a leveling agent (polyether-modified fluorosilicone oil, product model is TPD-FS8013) to obtain the coating.

[0123] Performance testing

[0124] After spraying the coatings prepared in the examples and comparative examples onto the glass substrate and curing to obtain the coatings, conduct performance testing, including the water contact angle and oil contact angle. After pasting and compressing with 3M tape, pull it forcefully at a 45° angle horizontally upward. Repeat 100 times, and use a ZR-SDJ-QH6 contact angle measuring instrument to measure the water contact angle and oil contact angle. The test results are shown in Table 1.

[0125] Table 1 Water contact angle and oil contact angle

[0126]

[0127]

[0128] Detect the stain resistance, adhesion and abrasion resistance of the coatings prepared in the detection examples and comparative examples. Among them, the adhesion detection method: The pull-off method is used to test the adhesion performance of the coating. Refer to GB / T 5210-2006 "Pull-off Adhesion Test for Paints and Varnishes". The abrasion resistance detection method: A steel wool abrasion testing machine is used for testing. Use 0000# steel wool, with an area of 10×10 mm, a stroke of 40 times per minute, a load of 100 g. The water contact angle of the test sample is measured every 100 rubs. When the water contact angle is less than 150°, the test is stopped and the final number of times is recorded; Stain resistance: Apply chili oil on the surface of the coating to be tested. After standing for 1 h, observe whether it can be wiped off; Grade 1 represents complete wiping off without residue, Grade 2 represents leaving about 30% faint traces, and Grade 3 represents leaving obvious traces with a trace area > 30%. The specific detection results are shown in Table 2.

[0129] Table 2 Stain resistance, adhesion and abrasion resistance

[0130] Adhesion force (MPa) Abrasion resistance (times) Stain resistance Example 1 7.25 3800 Grade 1 Example 2 6.95 3400 Grade 1 Example 3 7.38 3600 Grade 1 Example 4 7.08 3500 Grade 1 Comparative example 1 3.57 3100 Grade 2 Comparative example 2 4.08 2800 Grade 2 Comparative example 3 6.59 3200 Grade 2

[0131] As can be seen from Table 1 and Table 2, for the fluorine-containing composition prepared by the preparation method of the present invention, by compounding the modified titanium dioxide filler with the resin mixture and the photoinitiator, and then applying it to the coating, a coating surface with superhydrophobic and oleophobic properties can be obtained, which can significantly improve the waterproof and oil-proof performance of the coating.

[0132] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A highly oil- and water-resistant fluorine-containing composition, characterized in that: By weight parts, the fluorine-containing composition comprises the following chemical components: 70-80 parts of a resin mixture, 2-5 parts of a diisocyanate, 5-8 parts of a modified titanium dioxide filler, and 10-15 parts of modified glass flakes. The resin mixture comprises a fluorinated hydroxyacrylate resin and a polyurethane acrylate, and the mass ratio of the fluorinated hydroxyacrylate resin to the polyurethane acrylate is 3-5:1; The preparation method of the modified glass flakes is as follows: (a) Mix glass flakes with absolute ethanol, stir for 20-30 min, then add an ethanol solution of γ-aminopropyltrimethoxysilane, and stir at 55-65 °C for 1-3 h to obtain aminated glass flakes; (b) Add the aminated glass flakes into toluene, add acryloyl chloride under nitrogen protection, stir and react for 10-20 min, then add triethylamine, and stir and react at room temperature for 16-20 h to obtain acylated glass flakes; (c) Disperse the acylated glass flakes in DMF, add acrylic monomers, perfluorooctylethyl acrylate, and 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate, stir and mix evenly, then add azobisisobutyronitrile, and carry out graft copolymerization reaction under ultraviolet light irradiation at room temperature for 2-3 h to obtain modified glass flakes.

2. The highly oil- and water-resistant fluorine-containing composition according to claim 1, wherein: The preparation method of the modified titanium dioxide filler comprises the following steps: (1) Disperse titanium dioxide particles in water, then add a sodium silicate solution, stir evenly, add an acid for aging to obtain titanium dioxide coated with silica; (2) Disperse the titanium dioxide coated with silica in an ethanol-water mixed solution, add a mercapto silane coupling agent, stir and react. After the reaction is completed, filter, wash, and dry to obtain mercapto-functionalized titanium dioxide; (3) Add the mercapto-functionalized titanium dioxide into DMF, then add trifluoromethylacrylic acid and benzophenone, and carry out a thiol-ene reaction under ultraviolet light to obtain a modified titanium dioxide filler.

3. The highly oil- and water-resistant fluorine-containing composition according to claim 2, wherein: In step (1), the mass ratio of titanium dioxide to sodium silicate is 1:0.4-0.8, the aging temperature is 70-90 °C, and the aging time is 3-5 h; in step (2), the mass ratio of the mercapto silane coupling agent to the titanium dioxide coated with silica is 1:0.8-1.5, the mercapto silane coupling agent is 3-mercaptopropyltrimethoxysilane, the heating reaction temperature is 70-80 °C, and the heating reaction time is 2-4 h.

4. A highly oil- and water-resistant fluorine-containing composition according to claim 2, characterized in that: In step (3), the mass ratio of the mercapto-functionalized titanium dioxide, trifluoromethylacrylic acid, and benzophenone is 10-20:1.5-2.5:0.1-0.3, the thiol-ene reaction temperature is 40-50 °C, and the reaction time is 20-30 min.

5. The high anti-oil and waterproof fluorine-containing composition according to claim 1, characterized in that: In step (a), the mass ratio of glass flakes to γ-aminopropyltrimethoxysilane is 100:10-15, and the mass concentration of the ethanol solution of γ-aminopropyltrimethoxysilane is 5-7%; in step (b), the mass ratio of the aminated glass flakes, acryloyl chloride, and triethylamine is 100:8-12:12-15.

6. A high anti-oil and waterproof fluorine-containing composition according to claim 1, characterized in that: In step (c), the mass ratio of the acylated glass flakes to the total mass of the acrylic monomer, perfluorooctylethyl acrylate, and ethyl 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl] methacrylate is 100:20-25; the mass ratio of the acrylic monomer, perfluorooctylethyl acrylate, and ethyl 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl] methacrylate is 1:2:1; the addition amount of azobisisobutyronitrile is 2-3% of the total mass of the acrylic monomer, perfluorooctylethyl acrylate, and ethyl 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl] methacrylate.

7. A high anti-oil and waterproof fluorine-containing composition according to claim 1, characterized in that: The diisocyanate is isophorone diisocyanate or toluene diisocyanate.

8. The preparation method of a high anti-oil and waterproof fluorine-containing composition according to any one of claims 1-7, characterized in that: It includes the following steps: S1. Mix and disperse the fluorinated hydroxyacrylate resin and polyurethane acrylate in ethyl acetate at a mass ratio of 3-5:1, and stir evenly to obtain a resin mixture. S2. Add the modified titanium dioxide filler and modified glass flakes to the resin mixture in sequence, stir and disperse at 35-45 °C for 30-60 min; then add the diisocyanate, stir evenly for 10-20 min, and finally adjust the solid content to 30-35% to obtain a high oil- and water-proof fluorine-containing composition.

9. Use of a high oil- and water-proof fluorine-containing composition according to any one of claims 1-7 in a coating.

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