Silicon dioxide modified styrene-acrylic coating and preparation method thereof

Abstract

The invention relates to the technical field of styrene-acrylic coatings, and discloses a silicon dioxide modified styrene-acrylic coating and a preparation method thereof.Nanometer SiO2 is of a three-dimensional network structure,-OH groups contained on the surface of the nanometer SiO2 can react with IPDI to prepare nanometer SiO2 with-NCO groups contained on the surface, the nanometer SiO2 is chemically bonded with a tetraalkenyl bis (trifluoromethyl) biphenyl intermediate, and the surface of the nanometer SiO2 is modified. The problems of insufficient linear structure and cross-linking points of the styrene-acrylic emulsion are solved, the agglomeration phenomenon of the grafted and modified nano SiO2 is reduced, and the nano size is kept; fluorine-containing organic matter is large in fluorocarbon bond energy and has very special surface activity, hydrophobic fluorine-containing groups are closely arranged on the outer layer of a carbon chain, a shielding effect is generated on hydrophilic groups, and excellent weather resistance and hydrophobicity are achieved; the styrene-acrylic emulsion is modified by using the organic fluorine and the nano SiO2, the advantages of the organic fluorine and the nano SiO2 can be integrated and strongly combined, and the mechanical property is improved while the water resistance of a coating film is improved.

Description

Technical Field

[0001] The invention relates to the technical field of styrene acrylic coatings, in particular to a silicon dioxide modified styrene acrylic coating and a preparation method thereof. Background Art

[0002] Styrene acrylic emulsion is obtained by emulsion copolymerization of styrene and acrylate monomers. Its process is simple and low-cost, and it can be widely used in fields such as coatings and adhesives. The polymer chain segments of traditional styrene acrylic emulsion are mostly linear structures and lack cross-linking points, so their water resistance and heat resistance are poor. In addition, its molecular chain contains polar ester groups, which affect the performance of the coating due to water absorption and decomposition during the curing and film-forming process, limiting its application. In recent years, with the advancement of science and technology, the requirements for coatings have become increasingly higher. Therefore, the research on modified styrene acrylic emulsion is of great significance to improving the overall level of my country's coatings industry.

[0003] At present, the modification methods of styrene acrylic emulsion mainly include: organic silicon modification, organic fluorine modification, epoxy ester modification, nanoparticle modification, etc. Organic-inorganic nanocomposites have the advantages of both organic and inorganic materials, complementing each other's shortcomings, and can be used for modification research of coatings, plastics, rubber, etc. to improve the performance of materials; Invention patent CN112321765A discloses a waterproof coating based on self-crosslinking modified styrene acrylic emulsion and its preparation method and application. Emulsifier and deionized water are added to the reactor, stirred rapidly to fully emulsify the emulsifier solution, heated to 75 ° C, and then the mixture is added dropwise. The cross-linked modified styrene-acrylic emulsion is obtained by combining monomers of styrene, acrylic acid, butyl acrylate, 1,2-epoxy-7-octene and an initiator, adjusting the pH, and filtering to remove impurities. The introduced functional monomer components can undergo a cross-linking reaction during the resin curing and film-forming process, thereby improving the strength, toughness and waterproof performance of the styrene-acrylic emulsion waterproof coating. However, the water resistance of the modified coating is limited. The silica-modified styrene-acrylic coating prepared by the present invention utilizes a chemical bonding method. The side chain is a nano-silica modified with polyolefins, which can generate branched cross-linking with the styrene-acrylic emulsion, thereby improving the "hot sticky and cold brittle" disadvantage of the styrene-acrylic coating. Summary of the Invention

[0004] (1) Technical problems solved In view of the shortcomings of the prior art, the present invention provides a silica-modified styrene-acrylic coating and a preparation method thereof, which solves the problem of poor weather resistance and water resistance of styrene-acrylic coating.

[0005] (2) Technical solution A method for preparing a silica-modified styrene-acrylic coating, wherein the method for preparing the silica-modified styrene-acrylic coating is carried out according to the following steps: Step S1: Add tetrahydrofuran solvent to a reaction flask, add 2,2-bis(trifluoromethyl)diaminobiphenyl and glycidyl methacrylate, heat and stir to react, filter after the reaction, wash with deionized water and petroleum ether in sequence, and dry to obtain a tetraenylbis(trifluoromethyl)biphenyl intermediate. The preparation process is as follows:

[0006] Step S2: Add toluene solvent to the reaction bottle, add 100 parts by weight of nano-silica, ultrasonically disperse for 30-50 minutes, then add 150-250 parts of isophorone diisocyanate, stir and disperse under a nitrogen atmosphere, react at 80-110° C. for 5-8 hours, filter, wash with toluene, and centrifuge to obtain IPDI-modified SiO2.

[0007] Step S3: Add toluene as solvent to the reaction flask, add IPDI-modified SiO2, disperse evenly, then add tetraenylbis(trifluoromethyl)biphenyl intermediate and catalyst dibutyltin dilaurate, stir and react. After the reaction is completed, filter, wash with toluene, centrifuge and dry to obtain tetraenylbis(trifluoromethyl)biphenyl-modified SiO2.

[0008] Step S4, adding deionized water as a solvent to a reaction bottle equipped with two dropping funnels, adding 3-5 parts by weight of an emulsifier, sodium dodecylbenzenesulfonate, and 8-13 parts of OP-10, and stirring to dissolve; adding a mixture of polymerized monomers styrene, n-butyl acrylate, acrylic acid, and tetraenylbistrifluoromethylbiphenyl modified SiO2 to one of the dropping funnels; adding 4-6 parts of ammonium persulfate and an initiator of deionized water to the other dropping funnel, first dropwise adding 1 / 3 of the mixture, stirring for 2-4 hours, then adding 1 / 3 of the initiator, heating to react, initiating for 10-30 minutes, and then dropwise adding the remaining mixture and initiator. After complete dropwise addition, react at 75-95°C for 2-5 hours, cool to room temperature, adjust the pH to 7-8 with ammonia water, and finally add 1-2 parts of a defoamer and a leveling agent to obtain a silica-modified styrene acrylic coating.

[0009] Preferably, the mass ratio of the reactants in step S1 is 2,2-bis(trifluoromethyl)diaminobiphenyl: glycidyl methacrylate = 100:85-105.

[0010] Preferably, in step S1, the reaction time is 120-140° C., and the reflux time is 2-5 h.

[0011] Preferably, the mass ratio of the reactants in step S3 is IPDI-modified SiO2:organofluorine-modified tetraenyl alkyl alcohol:catalyst dibutyltin dilaurate=100:150-400:2-5.

[0012] Preferably, the reaction temperature in step S3 is 80-110° C., and the reaction time is 6-12 h.

[0013] Preferably, the mass ratio of the polymerized monomers in step S4 is styrene: n-butyl acrylate: acrylic acid: tetraenylbis(trifluoromethyl)biphenyl-modified SiO2=100:30-40:5-15:2-7.

[0014] (3) Beneficial technical effects The present invention firstly utilizes the epoxy group of glycidyl methacrylate to react with the amino group of 2,2-bis(trifluoromethyl)diaminobiphenyl to obtain a tetraenylbis(trifluoromethyl)biphenyl intermediate, then the -OH group on the surface of nano-SiO2 reacts with IPDI to prepare nano-SiO2 containing -NCO groups on the surface, which is then reacted with the hydroxyl group of the tetraenylbis(trifluoromethyl)biphenyl intermediate to prepare tetraenylbis(trifluoromethyl)biphenyl-modified SiO2, and finally copolymerized with monomers such as styrene and acrylic acid to obtain a silica-modified styrene-acrylic coating.

[0015] Nano-SiO2 has a three-dimensional network structure, a large specific surface area, and great activity. The -OH groups on the surface can react with IPDI to prepare nano-SiO2 with -NCO groups on the surface, which is then grafted with tetraenylbistrifluoromethylbiphenyl intermediates in the form of chemical bonds, thereby improving the single linear structure of the styrene acrylic emulsion and the problem of lacking crosslinking points. The agglomeration phenomenon of the grafted modified nano-SiO2 is reduced, and the solubility and dispersion properties in the coating are significantly improved, while maintaining the nano size. The crosslinking degree of the coating surface continues to increase, and the mechanical properties are correspondingly improved. The carbon-fluorine bond energy of fluorine-containing organic matter is large, and it has very special surface activity. It contains hydrophobic fluorine-containing groups, and the fluorine atoms are tightly arranged in the outer layer of the carbon chain, which has a shielding effect on the hydrophilic groups and has excellent weather resistance and hydrophobicity. Modifying the styrene acrylic emulsion with organic fluorine and nano-SiO2 can combine the advantages of the two, combining them strongly, improving the water resistance of the coating while improving the mechanical properties. DETAILED DESCRIPTION

[0016] To make the objectives, technical solutions, and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without inventive effort are within the scope of protection of the present invention.

[0017] Example 1 Step S1: Add tetrahydrofuran solvent to a reaction bottle, add 50 g of 2,2-bis(trifluoromethyl)diaminobiphenyl and 42 g of glycidyl methacrylate, heat and stir to react, reflux at 130° C. for 4 h, filter, wash with deionized water and petroleum ether in sequence, and dry to obtain a tetraenylbis(trifluoromethyl)biphenyl intermediate.

[0018] Step S2: Add toluene solvent to the reaction bottle, add 120g of nano-silica, ultrasonically disperse for 35min, then add 240g of isophorone diisocyanate, stir and disperse under a nitrogen atmosphere, react at 80°C for 6h, filter, wash with toluene, and centrifuge to obtain IPDI-modified SiO2.

[0019] Step S3: Add toluene solvent to the reaction bottle, add 20 g of IPDI-modified SiO2, disperse evenly, then add 40 g of tetraenylbis(trifluoromethyl)biphenyl intermediate and 3 g of catalyst dibutyltin dilaurate, stir and react, react at 100 ° C for 10 hours, filter, wash with toluene, centrifuge for 15 hours, and dry to obtain tetraenylbis(trifluoromethyl)biphenyl-modified SiO2.

[0020] Step S4, adding deionized water as a solvent to a reaction bottle equipped with two dropping funnels, adding 3.5g of emulsifier sodium dodecylbenzenesulfonate and 8g of OP-10, and stirring to dissolve; adding a mixture of 100g of styrene, 35g of n-butyl acrylate, 8g of acrylic acid and 2g of tetraenylbistrifluoromethylbiphenyl modified SiO2 to one of the dropping funnels; adding 4.5g of ammonium persulfate and an initiator of deionized water to the other dropping funnel, first adding 1 / 3 of the mixture dropwise, stirring for 3h, then adding 1 / 3 of the initiator, heating the reaction, initiating for 20min, and then adding the remaining mixture and initiator dropwise. After the addition is complete, react at 80°C for 3h, cool to room temperature, adjust the pH to 8 with ammonia water, and finally add 2g of defoamer and leveling agent to obtain a silica-modified styrene acrylic coating.

[0021] Example 2 Step S1: Add tetrahydrofuran solvent to a reaction bottle, add 100 g of 2,2-bis(trifluoromethyl)diaminobiphenyl and 100 g of glycidyl methacrylate, heat and stir to react, reflux at 135° C. for 3 h, filter, wash with deionized water and petroleum ether in sequence, and dry to obtain a tetraenylbis(trifluoromethyl)biphenyl intermediate.

[0022] Step S2: Add toluene solvent to the reaction bottle, add 30g of nano-silica, ultrasonically disperse for 45min, then add 80g of isophorone diisocyanate, stir and disperse under nitrogen atmosphere, react at 100°C for 7h, filter, wash with toluene, and centrifuge to obtain IPDI-modified SiO2.

[0023] Step S3: Add toluene solvent to the reaction bottle, add 150g of IPDI-modified SiO2, disperse evenly, then add 500g of tetraenylbis(trifluoromethyl)biphenyl intermediate and 2g of catalyst dibutyltin dilaurate, stir and react, react at 110°C for 9h, filter, wash with toluene, centrifuge for 15h, and dry to obtain tetraenylbis(trifluoromethyl)biphenyl-modified SiO2.

[0024] Step S4, adding deionized water as a solvent to a reaction bottle equipped with two dropping funnels, adding 5g of emulsifier sodium dodecylbenzenesulfonate and 12g of OP-10 by weight, and stirring to dissolve; adding a mixture of 100g of styrene, 40g of n-butyl acrylate, 10g of acrylic acid and 3.6g of tetraenylbistrifluoromethylbiphenyl modified SiO2 to one of the dropping funnels; adding 4g of ammonium persulfate and an initiator of deionized water to the other dropping funnel, first adding 1 / 3 of the mixture dropwise, stirring for 4h, then adding 1 / 3 of the initiator, heating the reaction, initiating for 30min, and then adding the remaining mixture and initiator dropwise. After the addition is complete, react at 75°C for 5h, cool to room temperature, adjust the pH to 7 with ammonia water, and finally add 1g of a defoamer and a leveling agent to obtain a silica-modified styrene acrylic coating.

[0025] Example 3 Step S1: Add tetrahydrofuran solvent to a reaction bottle, add 80 g of 2,2-bis(trifluoromethyl)diaminobiphenyl and 80 g of glycidyl methacrylate, heat and stir to react, reflux at 125° C. for 3 h, filter, wash with deionized water and petroleum ether in sequence, and dry to obtain a tetraenylbis(trifluoromethyl)biphenyl intermediate.

[0026] Step S2: Add toluene solvent to the reaction bottle, add 25g of nano-silica by weight, ultrasonically disperse for 40 minutes, then add 50g of isophorone diisocyanate, stir and disperse under a nitrogen atmosphere, react at 90°C for 7 hours, filter, wash with toluene, and centrifuge to obtain IPDI-modified SiO2.

[0027] Step S3: Add toluene solvent to the reaction bottle, add 60 g of IPDI-modified SiO2, disperse evenly, then add 180 g of tetraenylbis(trifluoromethyl)biphenyl intermediate and 5 g of catalyst dibutyltin dilaurate, stir and react, react at 100 ° C for 8 h, filter, wash with toluene, centrifuge for 24 h, and dry to obtain tetraenylbis(trifluoromethyl)biphenyl-modified SiO2.

[0028] Step S4, adding deionized water as a solvent to a reaction bottle equipped with two dropping funnels, adding 4g of emulsifier sodium dodecylbenzenesulfonate and 11g of OP-10 by weight, and stirring to dissolve; adding a mixture of 100g of styrene, 30g of n-butyl acrylate, 8g of acrylic acid and 5g of tetraenylbistrifluoromethylbiphenyl modified SiO2 to one of the dropping funnels; adding 5g of ammonium persulfate and an initiator of deionized water to the other dropping funnel, first adding 1 / 3 of the mixture dropwise, stirring for 4h, then adding 1 / 3 of the initiator, heating the reaction, initiating for 25min, and then adding the remaining mixture and initiator dropwise. After the addition is complete, react at 90°C for 3h, cool to room temperature, adjust the pH to 8 with ammonia water, and finally add 2g of defoamer and leveling agent to obtain a silica-modified styrene acrylic coating.

[0029] Example 4 Step S1: Add tetrahydrofuran solvent to a reaction bottle, add 90 g of 2,2-bis(trifluoromethyl)diaminobiphenyl and 95 g of glycidyl methacrylate, heat and stir to react, reflux at 140° C. for 4 h, filter, wash with deionized water and petroleum ether in sequence, and dry to obtain a tetraenylbis(trifluoromethyl)biphenyl intermediate.

[0030] Step S2: add toluene solvent to the reaction bottle, add 100 g of nano-silica by weight, ultrasonically disperse for 50 minutes, then add 220 g of isophorone diisocyanate, stir and disperse under a nitrogen atmosphere, react at 80° C. for 8 hours, filter, wash with toluene, and centrifuge to obtain IPDI-modified SiO2.

[0031] Step S3: Add toluene solvent to the reaction bottle, add 80g of IPDI-modified SiO2, disperse evenly, then add 280g of tetraenylbis(trifluoromethyl)biphenyl intermediate and 4g of catalyst dibutyltin dilaurate, stir and react, react at 110°C for 10h, filter, wash with toluene, centrifuge for 20h, and dry to obtain tetraenylbis(trifluoromethyl)biphenyl-modified SiO2.

[0032] Step S4, adding deionized water as a solvent to a reaction bottle equipped with two dropping funnels, adding 4g of emulsifier sodium dodecylbenzenesulfonate and 10g of OP-10 by weight, and stirring to dissolve; adding a mixture of 100g of styrene, 35g of n-butyl acrylate, 15g of acrylic acid and 7g of tetraenylbistrifluoromethylbiphenyl modified SiO2 to one of the dropping funnels; adding 6g of ammonium persulfate and an initiator of deionized water to the other dropping funnel, first adding 1 / 3 of the mixture dropwise, stirring for 3h, then adding 1 / 3 of the initiator, heating the reaction, initiating for 30min, and then adding the remaining mixture and initiator dropwise. After the addition is complete, react at 95°C for 4h, cool to room temperature, adjust the pH to 8 with ammonia water, and finally add 2g of defoamer and leveling agent to obtain a silica-modified styrene acrylic coating.

[0033] Comparative Example 1 Step S1: Add tetrahydrofuran solvent to a reaction bottle, add 80 g of 2,2-bis(trifluoromethyl)diaminobiphenyl and 80 g of glycidyl methacrylate, heat and stir to react, reflux at 125° C. for 3 h, filter, wash with deionized water and petroleum ether in sequence, and dry to obtain a tetraenylbis(trifluoromethyl)biphenyl intermediate.

[0034] Step S2, adding deionized water as a solvent to a reaction bottle equipped with two dropping funnels, adding 4g of an emulsifier, sodium dodecylbenzenesulfonate, and 11g of OP-10 by weight, and stirring to dissolve; adding a mixture of 100g of styrene, 30g of n-butyl acrylate, 8g of acrylic acid, and 7g of a tetraenylbistrifluoromethylbiphenyl intermediate as a polymerization monomer to one of the dropping funnels; adding 5g of ammonium persulfate and an initiator of deionized water to the other dropping funnel, first dropwise adding 1 / 3 of the mixture, stirring for 4h, then adding 1 / 3 of the initiator, heating the reaction, initiating for 25min, and then dropwise adding the remaining mixture and initiator. After the addition is complete, react at 90°C for 3h, cool to room temperature, adjust the pH to 8 with ammonia water, and finally add 2g of a defoamer and a leveling agent to obtain a modified styrene-acrylic coating.

[0035] Comparative Example 2 Step S1: Add toluene solvent to a reaction bottle, add 30g of nano-silica, ultrasonically disperse for 45min, then add 80g of isophorone diisocyanate, stir and disperse under a nitrogen atmosphere, react at 100°C for 7h, filter, wash with toluene, and centrifuge to obtain IPDI-modified SiO2.

[0036] Step S2, adding deionized water as a solvent to a reaction bottle equipped with two dropping funnels, adding 4g of emulsifier sodium dodecylbenzenesulfonate and 10g of OP-10 by weight, and stirring to dissolve; adding a mixture of 100g of styrene, 35g of n-butyl acrylate, 15g of acrylic acid and 7g of IPDI-modified SiO2 as a polymerization monomer to one of the dropping funnels; adding 6g of ammonium persulfate and an initiator of deionized water to the other dropping funnel, first dropwise adding 1 / 3 of the mixture, stirring for 3h, then adding 1 / 3 of the initiator, heating to react, initiating for 30min, and then dropwise adding the remaining mixture and initiator. After the dropwise addition is complete, react at 95°C for 4h, cool to room temperature, adjust the pH to 8 with ammonia water, and finally add 2g of a defoamer and a leveling agent to obtain a modified styrene-acrylic coating.

[0037] Contact angle test: The static contact angle between the sample surface and water was measured using a contact angle meter. The test temperature was 25°C, the volume of the test liquid was 3-5 μL, 5 points were tested for each sample, and the average value was taken.

[0038] Water absorption test: The emulsion to be tested was evenly coated on a glass plate to form a film, and then dried at 70°C for 3 hours. The emulsion-coated glass plate was immersed in distilled water and accurately weighed after 24 hours. The water absorption rate of the latex film was calculated according to the following formula: Water absorption (%) = (m2-m1) × 100% / (m1-m0) In the above formula, m0, m1 and m2 are the masses (g) of the glass plate, (glass plate + coating) and (glass plate + coating + water).

[0039]

[0040] As can be seen from the table above, with the increase of the content of fluorinated monomer and modified nano-SiO2, the contact angle of the coating increases first and then decreases, showing good hydrophobicity at the beginning. In Comparative Example 4, the water drop contact angle reaches 109.6°, which has strong hydrophobicity. This is because the fluorine atoms in the coating gather on the surface, resulting in a decrease in the surface energy of the coating and an increase in the hydrophobicity. In addition, with the increase of SiO2 content, the roughness of the coating surface is higher, and the contact angle is larger. In Comparative Example 2, there is no organic fluorine monomer, only IPDI modified The contact angle of water droplets on the surface of SiO2 is 70.6°, and the surface hydrophobicity is poor; the water absorption rate of the coating surface shows a downward trend, reaching a minimum of 3.6%. This is because fluorine has a large electronegativity, and the fluorine-containing side chain shields and protects the main chain and internal molecules. In addition, the grafting reaction of the modified SiO2 hybrid material and the styrene-acrylic emulsion makes the coating form a network structure, shortens the bond distance, improves the density of the coating, and hinders the diffusion of water molecules into the interior of the coating, so that the water absorption rate is significantly reduced, thereby improving the water resistance of the benzoic paint.

[0041] Mechanical properties test: The coating film was made into a 10 mm × 10 mm × 5 mm specimen, and the tensile strength and elongation at break were measured using a universal testing machine at a tensile speed of 100 mm / min.

[0042]

[0043] It can be seen from the above table that with the increase of SiO2 content, the tensile strength and elongation at break first increase and then decrease. When the polymer is subjected to external force, nano-SiO2 can act as a cross-linking point, has a large specific surface area, and exhibits strong activity, which produces a bonding effect with the olefins on the surface of the styrene-acrylic emulsion, thereby increasing the bond force between molecules; Nano-SiO2 has a small size effect and a three-dimensional network structure. Nano-dispersed SiO2 increases the cross-linking points and branching points of the styrene-acrylic emulsion molecular chain, so that a dense coating film is formed on the surface of the modified coating, cross-linked into macromolecules, reducing residual stress, and improving the mechanical properties of the coating; However, too much SiO2 will agglomerate and produce stress concentration, and SiO2 itself is relatively sparse and easily torn, so when the SiO2 content continues to increase, the tensile strength and elongation at break tend to decrease.

[0044] The above is only an embodiment of the present invention, and the common knowledge such as the specific structure and characteristics of the scheme is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A method for preparing a silica-modified styrene-acrylic coating, characterized in that: The preparation method of the silicon dioxide modified styrene acrylic coating is carried out according to the following steps: Step S1, adding tetrahydrofuran solvent to a reaction flask, adding 2,2-bis(trifluoromethyl)diaminobiphenyl and glycidyl methacrylate, heating and stirring to react, after the reaction is completed, filtering, washing with deionized water and petroleum ether in sequence, and drying to obtain a tetraenylbis(trifluoromethyl)biphenyl intermediate; Step S2, adding toluene solvent to a reaction flask, adding 100 parts by weight of nano-silica, ultrasonically dispersing for 30-50 minutes, then adding 150-250 parts of isophorone diisocyanate, stirring and dispersing under a nitrogen atmosphere, reacting at 80-110° C. for 5-8 hours, filtering, washing with toluene, and centrifuging to obtain IPDI-modified SiO2; Step S3, adding toluene as a solvent to the reaction flask, adding IPDI-modified SiO2, and evenly dispersing the mixture, then adding tetraenylbis(trifluoromethyl)biphenyl intermediate and catalyst dibutyltin dilaurate, stirring and reacting. After the reaction is completed, filtering, washing with toluene, centrifuging and drying to obtain tetraenylbis(trifluoromethyl)biphenyl-modified SiO2; Step S4, adding deionized water as a solvent to a reaction bottle equipped with two dropping funnels, adding 3-5 parts by weight of an emulsifier, sodium dodecylbenzenesulfonate, and 8-13 parts of OP-10, and stirring to dissolve; adding a mixture of polymerized monomers styrene, n-butyl acrylate, acrylic acid, and tetraenylbistrifluoromethylbiphenyl modified SiO2 to one of the dropping funnels; adding 4-6 parts of ammonium persulfate and an initiator of deionized water to the other dropping funnel, first dropwise adding 1 / 3 of the mixture, stirring for 2-4 hours, then adding 1 / 3 of the initiator, heating to react, initiating for 10-30 minutes, and then dropwise adding the remaining mixture and initiator. After complete dropwise addition, react at 75-95°C for 2-5 hours, cool to room temperature, adjust the pH to 7-8 with ammonia water, and finally add 1-2 parts of a defoamer and a leveling agent to obtain a silica-modified styrene acrylic coating.

2. The method for preparing a silicon dioxide-modified styrene-acrylic coating according to claim 1, wherein: The mass ratio of the reactants in step S1 is 2,2-bis(trifluoromethyl)diaminobiphenyl: glycidyl methacrylate = 100:85-105.

3. The method for preparing a silicon dioxide modified styrene acrylic coating according to claim 1, wherein: The step S1 comprises a reaction time of 120-140° C. and a reflux time of 2-5 h.

4. The method for preparing a silicon dioxide-modified styrene acrylic coating according to claim 1, wherein: The mass ratio of the reactants in step S3 is IPDI-modified SiO2:organofluorine-modified tetraenyl alkyl alcohol:catalyst dibutyltin dilaurate=100:150-400:2-5.

5. The method for preparing a silicon dioxide modified styrene acrylic coating according to claim 1, wherein: In step S3, the reaction temperature is 80-110° C., and the reaction time is 6-12 h.

6. The method for preparing a silicon dioxide-modified styrene acrylic coating according to claim 1, wherein: The mass ratio of the polymerized monomers in step S4 is styrene: n-butyl acrylate: acrylic acid: tetraenylbis(trifluoromethyl)biphenyl-modified SiO2=100:30-40:5-15:2-7.

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