Anti-ultraviolet coating for glass surface and preparation method thereof

Abstract

The invention relates to the technical field of coatings and discloses an anti-ultraviolet coating for glass surfaces and a preparation method thereof. The coating comprises the following raw materials: methyl methacrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate, a composite additive, an initiator, talcum powder, sodium hexametaphosphate, propylene glycol methyl ether, polyethyl acrylate, polydimethylsiloxane, and water. The composite additive is titanium dioxide, which is a surface-modified antifouling modified component. The alkenyl functional groups in the titanium dioxide structure can produce cross-linking polymerization with a matrix, effectively improving the adhesion and antifouling performance of the coating. The titanium dioxide can absorb, scatter and reflect ultraviolet light, thereby giving the coating good anti-ultraviolet performance. In addition, the structure contains a large number of silicon-oxygen bonds, carbon-fluorine bonds and long alkyl chains, further improving the antifouling performance of the coating.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to an anti-ultraviolet coating for glass surfaces and a preparation method thereof. Background Art

[0002] As people's requirements for decoration increase, more and more glass products are coated with protective and decorative coatings on their surfaces to improve their performance and appearance. At present, coatings are mainly divided into three types, namely acrylic, epoxy resin and polyurethane. Among them, acrylic coatings have excellent properties, such as good weather resistance, color retention and chemical resistance. These special properties make them widely used in the field of glass products, realizing the decoration of the appearance of glass while having a good protective effect.

[0003] With the continuous improvement of social and economic levels and the rapid development of science and technology, higher requirements are placed on the functionality of coatings. Compared with ordinary coatings, coatings used for glass surfaces need to have good UV protection. For example, photovoltaic glass, architectural glass, automotive glass, etc. are exposed to sunlight for a long time. Ultraviolet rays will accelerate the aging process of the glass surface coating, causing the coating to fade, peel or crack, thereby affecting the appearance and service life. In addition, dust, dirt and other impurities in the air are easily attached to the surface of the glass, which significantly reduces the light transmittance of the glass and affects the use effect of the glass. Therefore, the coating used for the glass surface should have good anti-fouling properties to enable the glass to maintain good light transmittance for a long time, thereby extending the service life of the glass and reducing maintenance costs.

[0004] In the prior art, the improvement of coating performance is often achieved by optimizing the basic formula. For example, the invention patent with announcement number CN111171662B discloses a roof waterproof coating and its preparation method. This invention uses a special modified graphene dispersion to modify the polymer emulsion. The surface modification of the emulsion through chemical reaction improves its tensile strength and elongation and reduces the water absorption of the product. At the same time, it improves UV resistance, with the mechanical retention rate exceeding 90% after UV aging for more than 1500 hours. The internal cross-linking technology of adding allyl siloxane and the introduction of phosphate ester improve the adhesion and water resistance of the coating. The post-cross-linking technology is introduced through the use of coupling agents to further improve the waterproofness and high-temperature stability of the film. Therefore, high-performance coatings can be prepared by targeted addition of optimized components during the coating preparation process. Summary of the Invention

[0005] In order to solve the problems mentioned in the background technology, the purpose of the present invention is to provide an anti-ultraviolet coating for glass surface and a preparation method thereof.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A method for preparing an anti-ultraviolet coating for glass surfaces, the coating comprising the following raw materials in parts by weight: 30-40 parts of methyl methacrylate, 20-30 parts of butyl acrylate, 10-20 parts of acrylic acid, 5-10 parts of hydroxyethyl acrylate, 4-8 parts of composite additives, 0.5-1.5 parts of initiator, 8-10 parts of talc, 1-3 parts of sodium hexametaphosphate, 1-2 parts of propylene glycol methyl ether, 1-3 parts of polyethyl acrylate, 2-4 parts of polydimethylsiloxane, and 40-60 parts of water;

[0008] The preparation method comprises the following steps:

[0009] (1) adding methyl methacrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate and composite additives into a reaction kettle, and mechanically stirring to obtain a premix;

[0010] (2) adding an initiator to the premix, mixing, raising the system temperature to 70-90°C, and keeping the temperature for 4-6 hours to obtain a polymer emulsion;

[0011] (3) adding the polymer emulsion obtained in step (2), talc, sodium hexametaphosphate, propylene glycol methyl ether, polyethyl acrylate, polydimethylsiloxane and water into a stirring tank, stirring at a stirring rate of 600 to 1000 r / min for 1 to 3 hours, standing to defoam, and obtaining a coating.

[0012] Furthermore, the preparation method of the composite additive comprises the following steps:

[0013] S1: Ultrasonic dispersion of titanium dioxide in dimethyl sulfoxide to form a dispersion, adding itaconic acid and an esterification catalyst to the dispersion, raising the system temperature to 100-110°C with stirring, maintaining the temperature for 5-9 hours, allowing the material to cool naturally, centrifuging to separate a solid material, washing the solid material, and vacuum drying to obtain modified titanium dioxide;

[0014] S2: Add modified titanium dioxide to N,N-dimethylformamide, ultrasonically disperse for 20 to 40 minutes, then add antifouling modification components and p-toluenesulfonic acid, increase the system temperature to 100 to 110°C, keep stirring for 6 to 10 hours, filter and separate the solid material, wash and dry it, and obtain a composite additive.

[0015] Furthermore, in step S1, the average particle size of the titanium dioxide is 5 μm.

[0016] Furthermore, in step S1, the esterification catalyst is any one of p-toluenesulfonic acid, aminosulfonic acid or trifluoromethanesulfonic acid.

[0017] Furthermore, in step S1, the mass ratio of titanium dioxide to itaconic acid is 1:0.1-0.3.

[0018] Technical principle: In the composite additive, first, the hydroxyl groups on the surface of titanium dioxide can react with the carboxyl groups in the itaconic acid structure under the action of an esterification catalyst, thereby introducing carboxyl groups and unsaturated olefinic functional groups on the surface of titanium dioxide to obtain modified titanium dioxide; secondly, under the action of p-toluenesulfonic acid, the carboxyl groups on the surface of the modified titanium dioxide can further react with the hydroxyl groups in the anti-fouling modified component structure to obtain a composite additive.

[0019] Furthermore, the preparation method of the antifouling modified component comprises the following steps:

[0020] The terminal hydroxyl fluorinated polysiloxane is mixed with dimethyl sulfoxide and stirred to form a uniform solution, and then the epoxy soybean oil and the phase transfer catalyst are added to the solution. After the addition is completed, the temperature is raised to 70-80°C, and the mixture is stirred at this temperature for 4-8 hours. The solvent is removed by distillation under reduced pressure to obtain an antifouling modified component.

[0021] Furthermore, the phase transfer catalyst is boron trifluoride ether complex.

[0022] Furthermore, the mass ratio of the terminal hydroxyl fluorinated polysiloxane to the epoxy soybean oil is 1:0.2-0.4.

[0023] Furthermore, the initiator is any one of azobisisobutyronitrile, azobiscyclohexylmethane or azobisisovaleronitrile.

[0024] Technical principle: In the anti-fouling modified component, under the action of a phase transfer catalyst, the hydroxyl group in the terminal hydroxyl fluorinated polysiloxane structure can react with the epoxy group in the epoxy soybean oil structure to obtain an anti-fouling modified component containing a hydroxyl group in the structure.

[0025] An anti-ultraviolet coating for glass surface is prepared by adopting the above preparation method.

[0026] Beneficial effects of the present invention:

[0027] (1) The present invention adds composite additives during the preparation process of the coating, and the raw materials cooperate with each other, so that the prepared coating has good antibacterial properties, antifouling properties and high adhesion, which is beneficial to extending the service life of the coating and reducing maintenance costs.

[0028] (2) The composite additive prepared by the present invention is titanium dioxide with a surface-modified antifouling modified component. After surface modification, the bonding force between the composite additive and the matrix material is greatly enhanced, which helps it to be evenly and stably dispersed in the matrix material. In addition, the unsaturated olefinic functional group in the structure of the composite additive can undergo cross-linking polymerization with polymerizing monomers such as methyl methacrylate under the action of an initiator, thereby increasing the cross-linking density, making the interface bonding tighter, and effectively improving the adhesion and antifouling performance of the coating. On the one hand, titanium dioxide can absorb, scatter and reflect ultraviolet light, and is an effective ultraviolet shielding agent, which can give the coating good anti-ultraviolet performance and reduce the problems of aging, fading, peeling or cracking of the coating caused by ultraviolet radiation. On the other hand, the composite additive contains a large number of silicon-oxygen bonds, carbon-fluorine bonds and long alkyl chains, so that the surface of the coating has a very low surface energy, so that the liquid and the coating surface do not wet, and impurities such as dust and dirt in the air are difficult to adhere to the coating surface, thereby achieving the purpose of antifouling, avoiding the coating on the glass surface from affecting the visual experience due to accumulation of dirt, reducing the number of cleaning times and maintenance costs of the glass, and effectively extending the service life of the glass.

[0029] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 This is an infrared spectrum test chart of the modified titanium dioxide and composite additives prepared in Example 1 of the present invention.

[0032] Figure 2 This is an infrared spectrum test chart of the antifouling modified component prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0034] Example 1. 1. Preparation of composite additives

[0035] S1: 5 g of titanium dioxide with an average particle size of 5 μm was ultrasonically dispersed in dimethyl sulfoxide to form a dispersion. 1.2 g of itaconic acid and 0.05 g of p-toluenesulfonic acid were added to the dispersion. After the addition, the system temperature was raised to 105° C. with stirring and kept warm for 7 h. The material was allowed to cool naturally, and the solid material was separated by centrifugation. The solid material was washed and vacuum dried to obtain modified titanium dioxide.

[0036] S2: Add 5 g of modified titanium dioxide to N,N-dimethylformamide and ultrasonically disperse for 30 minutes. Then add 2.6 g of antifouling modification component and 0.1 g of p-toluenesulfonic acid. Raise the system temperature to 105°C, keep stirring for 8 hours, filter and separate the solid material, wash and dry it, and obtain a composite additive.

[0037] The modified titanium dioxide and composite additives were analyzed by infrared spectroscopy using AVATAR-360 Fourier transform infrared spectrometer. Figure 1 As shown by Figure 1 It can be seen that in the infrared spectrum of modified titanium dioxide, 1755cm -1 The absorption peak of the ester group C=O appears at 1741 cm -1 The absorption peak of carboxyl group C=O appears at 1030cm -1 The absorption peak of the carbon-hydrogen bond in the carbon-carbon double bond appears at 1760cm -1 The absorption peak of the ester group C=O appears at 1030cm -1 The Si-O absorption peak appears at 1061 cm -1 The absorption peak of ether bond COC appears at 3045 cm -1 The absorption peak of the carbon-hydrogen bond in the carbon-carbon double bond appears at .

[0038] 2. Preparation of antifouling modified components

[0039] 5 g of terminal hydroxyl fluorinated polysiloxane was mixed with dimethyl sulfoxide and stirred to form a uniform solution. Then, 1.8 g of epoxy soybean oil and 0.1 g of boron trifluoride ether complex were added to the solution. After the addition was completed, the temperature was raised to 75°C and stirred at this temperature for 6 hours. The solvent was removed by distillation under reduced pressure to obtain an antifouling modified component.

[0040] The antifouling modified components were analyzed by infrared spectroscopy using AVATAR-360 Fourier transform infrared spectrometer. Figure 2 As shown by Figure 2 It can be seen that in the infrared spectrum of the antifouling modified component, 1016 cm -1 The Si-O absorption peak appears at 1263 cm -1The absorption peak of Si-C appears at 1750cm -1 The absorption peak of the ester group C=O appears at 1053 cm -1 The absorption peak of ether bond COC appears at 3310 cm -1 The absorption peak of hydroxyl group OH appears at

[0041] 3. Preparation of coating

[0042] (1) Add 30 g of methyl methacrylate, 20 g of butyl acrylate, 10 g of acrylic acid, 5 g of hydroxyethyl acrylate and 4 g of composite additives into a reactor and stir mechanically to obtain a premix;

[0043] (2) adding 0.5 g of azobisisobutyronitrile to the premix, mixing well, raising the system temperature to 70°C and keeping the temperature for 4 h to obtain a polymer emulsion;

[0044] (3) The polymer emulsion obtained in step (2), 8 g of talc, 1 g of sodium hexametaphosphate, 1 g of propylene glycol methyl ether, 1 g of polyethyl acrylate, 2 g of polydimethylsiloxane and 40 g of water were added to a stirring tank, stirred at a stirring rate of 600 r / min for 1 h, and allowed to stand for defoaming to obtain a coating.

[0045] Example 2. Preparation of coating

[0046] (1) Add 35 g of methyl methacrylate, 25 g of butyl acrylate, 15 g of acrylic acid, 8 g of hydroxyethyl acrylate, and 7 g of a composite additive to a reactor, and mechanically stir until uniform, to obtain a premix;

[0047] (2) Add 1 g of azobisisobutyronitrile to the premix, mix well, and then raise the system temperature to 80°C and keep warm for 5 hours to obtain a polymer emulsion;

[0048] (3) The polymer emulsion obtained in step (2), 9 g of talc, 2 g of sodium hexametaphosphate, 1.5 g of propylene glycol methyl ether, 2 g of polyethyl acrylate, 3 g of polydimethylsiloxane and 50 g of water were added to a stirred tank, stirred at a stirring rate of 800 r / min for 2 h, and allowed to stand for defoaming to obtain a coating.

[0049] The preparation method of the composite additive is the same as that in Example 1.

[0050] Example 3. Preparation of coating

[0051] (1) Add 40 g of methyl methacrylate, 30 g of butyl acrylate, 20 g of acrylic acid, 10 g of hydroxyethyl acrylate and 8 g of composite additives into a reactor and stir mechanically to obtain a premix;

[0052] (2) adding 1.5 g of azobisisobutyronitrile to the premix, mixing well, raising the system temperature to 90°C and keeping the temperature for 6 h to obtain a polymer emulsion;

[0053] (3) The polymer emulsion obtained in step (2), 10 g of talc, 3 g of sodium hexametaphosphate, 2 g of propylene glycol methyl ether, 3 g of polyethyl acrylate, 4 g of polydimethylsiloxane and 60 g of water were added to a stirred tank, stirred at a stirring rate of 1000 r / min for 3 h, and allowed to stand for defoaming to obtain a coating.

[0054] The preparation method of the composite additive is the same as that in Example 1.

[0055] Comparative Example 1. Preparation of coating

[0056] (1) Add 35 g of methyl methacrylate, 25 g of butyl acrylate, 15 g of acrylic acid and 8 g of hydroxyethyl acrylate into a reactor and stir mechanically to obtain a premix;

[0057] (2) Add 1 g of azobisisobutyronitrile to the premix, mix well, and then raise the system temperature to 80°C and keep warm for 5 hours to obtain a polymer emulsion;

[0058] (3) The polymer emulsion obtained in step (2), 7 g of titanium dioxide with an average particle size of 5 μm, 9 g of talc, 2 g of sodium hexametaphosphate, 1.5 g of propylene glycol methyl ether, 2 g of polyethyl acrylate, 3 g of polydimethylsiloxane and 50 g of water were added to a stirring tank, stirred at a stirring rate of 800 r / min for 2 h, and allowed to stand for defoaming to obtain a coating.

[0059] Comparative Example 2. Preparation of coating

[0060] (1) Add 35 g of methyl methacrylate, 25 g of butyl acrylate, 15 g of acrylic acid, 8 g of hydroxyethyl acrylate and 7 g of antifouling modification component to a reactor and stir mechanically to obtain a premix;

[0061] (2) Add 1 g of azobisisobutyronitrile to the premix, mix well, and then raise the system temperature to 80°C and keep warm for 5 hours to obtain a polymer emulsion;

[0062] (3) The polymer emulsion obtained in step (2), 9 g of talc, 2 g of sodium hexametaphosphate, 1.5 g of propylene glycol methyl ether, 2 g of polyethyl acrylate, 3 g of polydimethylsiloxane and 50 g of water were added to a stirred tank, stirred at a stirring rate of 800 r / min for 2 h, and allowed to stand for defoaming to obtain a coating.

[0063] The preparation method of the antifouling modified component is the same as that in Example 1.

[0064] Comparative Example 3. Preparation of coating

[0065] (1) Add 35 g of methyl methacrylate, 25 g of butyl acrylate, 15 g of acrylic acid and 8 g of hydroxyethyl acrylate into a reactor and stir mechanically to obtain a premix;

[0066] (2) Add 1 g of azobisisobutyronitrile to the premix, mix well, and then raise the system temperature to 80°C and keep warm for 5 hours to obtain a polymer emulsion;

[0067] (3) The polymer emulsion obtained in step (2), 9 g of talc, 2 g of sodium hexametaphosphate, 1.5 g of propylene glycol methyl ether, 2 g of polyethyl acrylate, 3 g of polydimethylsiloxane and 50 g of water were added to a stirred tank, stirred at a stirring rate of 800 r / min for 2 h, and allowed to stand for defoaming to obtain a coating.

[0068] Performance testing:

[0069] The coatings prepared in Examples 1 to 3 of the present invention and Comparative Examples 1 to 3 were evenly applied to a clean tinplate surface that had been sandblasted to prepare a sample that met the specifications. After being thoroughly dried, the performance test was performed. The adhesion test of the sample was performed according to GB / T 5210-2006 "Test for adhesion of paints and varnishes by pull-off method"; the sample was placed under an ultraviolet wavelength of 313 nm and an irradiance of 0.54 W / m 2 The samples were placed in a UV aging box to observe the time when yellowing occurs and to judge the UV resistance of the samples. The water contact angle of the samples was tested using a PZ-200SD contact angle meter to judge the anti-fouling performance of the samples. The specific test results are shown in Table 1:

[0070] Table 1 - Performance Test

[0071] Adhesion (MPa) Yellowing time (h) Water contact angle (°) Example 1 12 ＞240 150 Example 2 13 ＞240 152 Example 3 12 ＞240 151 Comparative Example 1 4 ＜150 105 Comparative Example 2 5 ＜48 140 Comparative Example 3 4 ＜48 104

[0072] From the test results in Table 1, it can be seen that the samples prepared in Examples 1 to 3 have good ultraviolet resistance, antifouling performance and high adhesion; in the sample prepared in Comparative Example 1, titanium dioxide is used to replace the composite additive. Since it cannot cross-link with the matrix, the antifouling performance and adhesion of the sample are poor, and the titanium dioxide that has not been organically modified may agglomerate in the matrix, resulting in a decrease in the ultraviolet resistance of the sample; in the sample prepared in Comparative Example 2, an antifouling modified component is used to replace the composite additive. Since it cannot cross-link with the matrix, the ultraviolet resistance, antifouling performance and adhesion of the sample are not as good as those of the embodiment; in the sample prepared in Comparative Example 3, no composite additive is added, so the various properties of the sample are poor.

[0073] The above content is merely an example and explanation of the concept of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A method for preparing an anti-ultraviolet coating for glass surface, characterized in that: The coating comprises the following raw materials in parts by weight: 30-40 parts of methyl methacrylate, 20-30 parts of butyl acrylate, 10-20 parts of acrylic acid, 5-10 parts of hydroxyethyl acrylate, 4-8 parts of composite additives, 0.5-1.5 parts of initiator, 8-10 parts of talc, 1-3 parts of sodium hexametaphosphate, 1-2 parts of propylene glycol methyl ether, 1-3 parts of polyethyl acrylate, 2-4 parts of polydimethylsiloxane, and 40-60 parts of water; The preparation method comprises the following steps: (1) Add methyl methacrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate and composite additives into a reactor and mechanically stir them to obtain a premix; (2) Add the initiator to the premix, mix well, raise the system temperature to 70-90°C, and keep it warm for 4-6 hours to obtain a polymer emulsion; (3) adding the polymer emulsion obtained in step (2), talc, sodium hexametaphosphate, propylene glycol methyl ether, polyethyl acrylate, polydimethylsiloxane and water into a stirring tank, stirring at a stirring rate of 600 to 1000 r / min for 1 to 3 hours, and standing to defoam to obtain a coating; The preparation method of the composite additive comprises the following steps: S1: Ultrasonic dispersion of titanium dioxide in dimethyl sulfoxide to form a dispersion, adding itaconic acid and an esterification catalyst to the dispersion, raising the system temperature to 100-110°C with stirring, maintaining the temperature for 5-9 hours, allowing the material to cool naturally, centrifuging to separate a solid material, washing the solid material, and vacuum drying to obtain modified titanium dioxide; S2: adding modified titanium dioxide to N,N-dimethylformamide, ultrasonically dispersing for 20 to 40 minutes, then adding antifouling modification components and p-toluenesulfonic acid, raising the system temperature to 100 to 110°C, stirring at this temperature for 6 to 10 hours, filtering and separating the solid material, washing and drying to obtain a composite additive; The preparation method of the antifouling modified component comprises the following steps: The terminal hydroxyl fluorinated polysiloxane is mixed with dimethyl sulfoxide and stirred to form a uniform solution, and then the epoxy soybean oil and the phase transfer catalyst are added to the solution. After the addition is completed, the temperature is raised to 70-80°C, and the mixture is stirred at this temperature for 4-8 hours. The solvent is removed by distillation under reduced pressure to obtain an antifouling modified component.

2. The method for preparing an anti-ultraviolet coating for glass surface according to claim 1, characterized in that: In step S1, the average particle size of the titanium dioxide is 5 μm.

3. The method for preparing an anti-ultraviolet coating for glass surface according to claim 1, characterized in that: In step S1, the esterification catalyst is any one of p-toluenesulfonic acid, aminosulfonic acid or trifluoromethanesulfonic acid.

4. The method for preparing an anti-ultraviolet coating for glass surface according to claim 1, characterized in that: In step S1, the mass ratio of titanium dioxide to itaconic acid is 1:0.1-0.

3.

5. The method for preparing an anti-ultraviolet coating for glass surface according to claim 1, characterized in that: The phase transfer catalyst is boron trifluoride ether complex.

6. The method for preparing an anti-ultraviolet coating for glass surface according to claim 1, characterized in that: The mass ratio of the terminal hydroxyl fluorinated polysiloxane to the epoxy soybean oil is 1:0.2-0.

4.

7. The method for preparing an anti-ultraviolet coating for glass surface according to claim 1, characterized in that: The initiator is any one of azobisisobutyronitrile, azobiscyclohexylmethane or azobisisovaleronitrile.

8. An anti-ultraviolet coating for glass surface, characterized in that: The method according to claim 1 is used for preparing the present invention.

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