Sulfonyl-modified silicon-based hybrid super-hydrophilic anti-fog resin as well as preparation method and application thereof

Abstract

The invention discloses sulfo group modified silicon-based hybridized super-hydrophilic anti-fog resin as well as a preparation method and application of the sulfo group modified silicon-based hybridized super-hydrophilic anti-fog resin. The silicon-based hybrid super-hydrophilic anti-fog resin is based on polysiloxane modified acrylic resin, a functional monomer containing a sulfonic acid group is introduced, the dosage is controlled, a spraying process is combined, a prepared coating has excellent anti-fog performance, high transparency and mechanical stability, the water contact angle of an obtained coating film is 5-6 degrees, the hardness is 2-3H, the adhesive force is 0 grade, and the anti-fog performance is good. The acid and alkali resistance test lasts for more than 30 hours, and super hydrophilicity is realized. The coating shows excellent antifogging performance under the steam environment of 80 DEG C and the freezing environment of-15 DEG C, and is suitable for antifogging treatment of substrates such as optical devices and automobile glass.

Description

Technical Field

[0001] The present invention relates to a super-hydrophilic anti-fog resin, in particular to a sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin and a preparation method and application thereof, which is suitable for fields such as optical devices, automotive glass, plastic substrates and medical equipment. Background Art

[0002] With the rapid development of modern architecture and transportation facilities, society's demand for functional surface coatings is growing. Transparent substrates such as glass curtain walls and car windshields are prone to fog condensation, affecting light transmittance and safety. Superhydrophilic coating technology provides an effective solution to this problem. This type of coating constructs a special surface microstructure and structure, allowing water droplets to quickly spread across the coating surface to form a uniform water film, thereby avoiding visual blur caused by light scattering. Traditional superhydrophilic coatings mostly use inorganic nanomaterial systems. Although they have significant anti-fog effects, they suffer from problems such as high coating brittleness and poor adhesion. They are prone to cracking and falling off under mechanical friction or temperature changes.

[0003] Chinese invention patent application CN116656193B discloses a super-hydrophilic coating and a method for forming a wear-resistant and boiling-resistant super-hydrophilic coating. The preparation process of this coating is relatively complex, requiring precise control of the ratios and reaction conditions of nanotubes, nanoparticles, different types of resins, surfactants, etc., and the curing temperature is relatively high (150-220°C), making it unsuitable for certain heat-sensitive substrates.

[0004] Chinese invention patent application CN111234288A discloses a method for preparing a hydrophilic polymer anti-fog coating, which is prepared through silane coupling agent modification and UV-induced polymerization. However, the anti-fog coating produced by this method exhibits average abrasion resistance and water resistance, and its anti-fog effect may decrease after long-term use. Furthermore, the UV curing process increases production costs and process complexity.

[0005] Chinese invention patent CN111574899B discloses an organic-inorganic hybrid anti-fog coating and its preparation method. The coating combines a hydrophilic acrylate resin with an organic-inorganic hybrid silica sol containing a quaternary ammonium salt. Migration of the quaternary ammonium salt can lead to uneven coating properties. Furthermore, the coating lacks flexibility and is prone to cracking under bending or impact.

[0006] Chinese invention patent CN105176293B discloses a super-hydrophilic coating and its preparation method. The coating uses peroxide to oxidize a mercaptosilane coupling agent into a sulfonic acid group and mixes it with a resin, which improves the weather resistance of the coating to a certain extent. However, the oxidation reaction conditions and reaction degree are difficult to control, solvents may be produced, and performance may be degraded in extreme environments (such as strong acids and strong bases).

[0007] In general, while acrylic resin-based super-hydrophilic coatings have attracted widespread attention for their excellent film-forming properties and flexibility, these coatings, which utilize a water-based acrylic resin as a matrix and impart super-hydrophilic properties through a hybridization process, offer outstanding environmental performance and low VOC emissions. However, existing technologies still face challenges such as difficulty balancing mechanical strength and hydrophilicity, uneven dispersion of inorganic nanoparticles, and a significant decrease in super-hydrophilicity at low and high temperatures. Summary of the Invention

[0008] In response to the shortcomings of the prior art, the present invention aims to provide a sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin and a preparation method thereof. The coating prepared using the silicon-based hybrid super-hydrophilic anti-fog resin has excellent anti-fog performance, high transparency and mechanical stability. The obtained coating has a water contact angle of 4~7°, a hardness of 2~3H, an adhesion of level 0, and an acid and alkali resistance test of >30h.

[0009] Another object of the present invention is to provide the application of the sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin in optical devices, automotive glass or medical equipment In order to achieve the purpose of the present invention, the technical solution provided by the present invention is as follows: A method for preparing a sodium sulfonate-modified silicon-based hybrid super-hydrophilic anti-fog resin comprises the following steps: (1) In parts by weight, 0.1-40 parts of organosilicon monomer are heated to 40-80°C; 0.02-0.08 parts of acidic catalyst are uniformly mixed with 0.5-16 parts of deionized water and 0.5-16 parts of cosolvent A, and the mixture is added dropwise to the organosilicon monomer and kept warm for 4-12 hours; after the end of the heat preservation, the cosolvent is removed to obtain polyorganosiloxane; (2) In parts by weight, 50-100 parts of cosolvent B are heated to 70-90°C; 7-15 parts of hydroxyl-containing acrylate monomers, 2-12 parts of acrylic acid and / or methacrylic acid, 30-55 parts of acrylate monomers and / or methacrylate monomers, 6-21 parts of benzene ring-containing monomers, 3-8 parts of double-bond siloxanes, and 3-8 parts of initiator A are mixed uniformly and then added dropwise to the cosolvent at a uniform rate. The addition is completed within 2-4 hours. After keeping the mixture warm for 3-5 hours, the mixture is cooled to below 60°C, 1-10 parts of an alkaline neutralizer is added to adjust the degree of neutralization, 15-40 parts of polyorganosiloxane are added, the mixture is mixed uniformly at 40-60°C, and the mixture is dispersed in 50-300 parts of deionized water under stirring to prepare a polyorganosiloxane-modified acrylate aqueous dispersion; (3) The sodium sulfonate compound and deionized water are mixed in a mass ratio of 1:0.5-4, and stirred until completely dissolved to obtain a sodium sulfonate aqueous solution; the polyorganosiloxane modified acrylate aqueous dispersion and the sodium sulfonate aqueous solution are blended in a mass ratio of 1:0.1-0.5, 1-5 parts by weight of initiator B are added and stirred for reaction for 30-60 minutes to obtain a sulfonic acid group-modified silicon-based hybrid super hydrophilic anti-fog resin.

[0010] To further achieve the purpose of the present invention, preferably, the silicone monomer is at least two of methyltrimethoxysilane, propyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, dimethyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane and γ-glycidoxypropylmethyldiethoxysilane; the acidic catalyst is one or more of hydrochloric acid, phosphoric acid, acetic acid, oxalic acid, diisopropyl phosphite, sodium diethyl phosphite, and sodium methylphosphonate; and the cosolvent A is one or more of ethylene glycol, propylene glycol, isopropyl alcohol, n-butanol, isobutanol, propylene glycol methyl ether, propylene glycol propyl ether, ethylene glycol butyl ether, dipropylene glycol methyl ether, and dipropylene glycol butyl ether.

[0011] Preferably, the acrylic acid ester monomer is one or more of acrylic acid ester, ethyl acrylate, butyl acrylate, hexyl acrylate and octyl acrylate; the methacrylic acid ester monomer is one or more of methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate and octyl methacrylate; the benzene ring-containing monomer is one or more of styrene and methyl styrene; the cosolvent B is one or more of ethylene glycol, propylene glycol, isopropanol, n-butanol, isobutanol, propylene glycol methyl ether, propylene glycol propyl ether, ethylene glycol butyl ether, dipropylene glycol methyl ether and dipropylene glycol butyl ether; the alkaline neutralizer is one or more of ammonia water, diethanolamine, triethanolamine, triethylamine, N, N-dimethylethanolamine and 2-amino-2-methyl-propanol, tetramethylammonium hydroxide; the initiator A is one or more of azobisisobutyronitrile, azobisisoheptylonitrile, benzoyl peroxide and cumene hydroperoxide.

[0012] Preferably, the hydroxyl-containing acrylic acid ester monomer is one or more of hydroxyethyl acrylate, hydroxypropyl acrylate and hydroxybutyl acrylate; the hydroxyl-containing methacrylic acid ester monomer is one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate and hydroxybutyl methacrylate.

[0013] Preferably, the double bond-containing organosilicon monomer is one or more of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, γ-methacryloxypropyltrimethoxysilane and vinyltriacetoxysilane.

[0014] Preferably, before adding initiator A in step (2), 0 to 8 parts by weight of epoxy resin is further added; the epoxy resin is one or more of epoxy resin E-03, epoxy resin E-06, epoxy resin E-12, epoxy resin E-20, epoxy resin E-21, epoxy resin E-44, epoxy resin E-51, and epoxy resin E-54.

[0015] Preferably, the sodium sulfonate is one or more of sodium α-olefin sulfonate, sodium allyl sulfonate, sodium α-olefin sulfonate, sodium allyl sulfonate, 2-acrylamide-2-methylpropanesulfonic acid, sodium vinyl sulfonate, and sodium styrene sulfonate; and the initiator B is one or more of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, and cumene hydroperoxide.

[0016] Preferably, the solvent removal in step (1) is carried out at 40-60°C; and the stirring until complete dissolution in step (3) is carried out at 35-60°C for 1-4 hours until complete dissolution.

[0017] A sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin is prepared by the above preparation method.

[0018] The sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin is used in optical devices, automobile glass or medical equipment.

[0019] Compared with the prior art, the present invention has the following advantages: The present invention is based on polyorganosiloxane-modified acrylic resin and introduces a functional monomer containing a sulfonic acid group. It has excellent anti-fog performance, high transparency and mechanical stability. The resulting coating has a water contact angle of 5-6°, a hardness of 2-3H, an adhesion level of 0, and an acid and alkali resistance test of >30h. It has excellent comprehensive performance and effectively solves the problems faced by the existing technology, such as the difficulty in balancing mechanical strength and hydrophilicity, uneven dispersion of inorganic nanoparticles, and a significant decrease in super-hydrophilicity under low and high temperature environments.

[0020] The coating produced by this invention exhibits no noticeable condensation under both 80°C hot steam and -15°C freezing conditions, achieving a water contact angle as low as 5.7°, significantly superior to conventional inorganic coatings and unmodified coatings. This is due to the multiple hydrogen bond networks formed by the sulfonic acid groups (-SO⁻) with water molecules, which enhance surface wettability.

[0021] By optimizing the sodium sulfonate content, the coating of the present invention remains uniform and transparent without whitening. Conventional inorganic coatings (such as Comparative Example 5) also suffer from reduced transparency due to particle aggregation.

[0022] The coating obtained in this invention achieved a pencil hardness of 2H and an adhesion level of 0 (Example), significantly superior to the comparative example. This is due to the Si-OC chemical bonds formed between PSiPA and the substrate, as well as the three-dimensional cross-linked network structure, which enhances the coating's wear resistance and adhesion, resulting in excellent mechanical stability.

[0023] After aging at 180°C for 7 days, the water contact angle of the coating obtained in the present invention is maintained at 5.3°~6.0° (Example). 5% The temperature of the coating was 165℃, and the thermogravimetric analysis showed that the residual mass at 600℃ was 7 wt.%. After acid and alkali immersion for 30 h, the super hydrophilicity of the coating was not significantly affected, showing excellent thermal stability and acid resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the hydrolysis and condensation of silicone monomers to form a Si-O-Si network.

[0025] Figure 2 Schematic diagram of the free radical polymerization of acrylic resin.

[0026] Figure 3 Schematic diagram of the principle of introducing sulfonic acid compounds into organopolysiloxane to modify acrylic resin.

[0027] Figure 4 These are infrared spectrum test charts of Example 1 of the present invention and Comparative Examples 1, 2, and 3.

[0028] Figure 5 This is a hot steam anti-fog performance diagram of the embodiment of the present invention and comparative examples 1, 2, and 3. DETAILED DESCRIPTION

[0029] For a better understanding of the present invention, the present invention is further described below with reference to the accompanying drawings and specific embodiments, but the embodiments of the present invention are not limited thereto. The embodiments described are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] The sodium sulfonate-modified silicon-based hybrid super-hydrophilic anti-fog resin is obtained by reacting a polyorganosiloxane-modified acrylate aqueous dispersion with a sodium sulfonate aqueous solution under the action of an initiator. The polyorganosiloxane-modified acrylate aqueous dispersion is prepared by uniformly mixing a hydroxyl-containing acrylate monomer, acrylic acid and / or methacrylic acid, an acrylate monomer and / or methacrylate monomer, a benzene ring-containing monomer, a double-bond-containing siloxane, and an initiator A, and then dropwise adding the mixture into a cosolvent. The dropwise addition is completed within 2-4 hours, and the mixture is kept warm for 3-5 hours, then cooled to below 60°C, an alkaline neutralizer is added to adjust the neutralization degree, and the polyorganosiloxane is added, followed by uniform mixing at 40-60°C to obtain the anti-fog resin. The polyorganosiloxane is prepared by uniformly mixing an acidic catalyst, deionized water, and the cosolvent A, and then dropwise adding the mixture into the organosilicon monomer. The mixture is kept warm for reaction for 4-12 hours, and the solvent is removed after the end of the heat preservation to obtain the anti-fog resin.

[0031] In the above preparation process, the organosilicon monomer undergoes a dehydration condensation reaction under the action of deionized water, cosolvent and acidic catalyst to form an organopolysiloxane network with Si-O-Si bonding, such as Figure 1 As shown, the product formed after hydrolysis and polycondensation has a highly cross-linked spatial network structure with Si-O-Si bonds as the backbone, which can significantly improve the mechanical strength of the coating. The present invention can also achieve a very complete and uniform hydrolysis and polycondensation of the siloxane by adjusting the ratio of the siloxane monomers to achieve an R / Si ratio of less than 1.6 and a Ph / R value of less than 0.125.

[0032] The multiple cross-linking hybridization and curing process of acrylic resin and polysiloxane improves the coating performance through intermolecular chemical reactions, such as Figure 2 As shown in the figure, the flexible segments of the acrylic resin react with the Si-OH groups of the polysiloxane under the action of a coupling agent, forming Si-O-Si bonds and building a preliminary cross-linked network. During the subsequent curing process, further dehydration and condensation occur to form a dense, multi-cross-linked structure. The epoxy groups in the polysiloxane and E-51 undergo ring opening under the action of the curing agent, enhancing the bonding effect with the substrate.

[0033] The introduction of organopolysiloxane promotes the formation of Si-O-Si structures. After curing, the intensity of the related absorption peaks further increases, indicating that it facilitates the condensation reaction of polysiloxane and the construction of a three-dimensional network structure. The alkoxy groups in the silane coupling agent, upon hydrolysis, generate silanols, which undergo a condensation reaction with the hydroxyl groups in the resin. At the same time, the silanols can also self-crosslink to form a dense Si-O-Si structure. This structure gives the material a higher crosslinking density, thereby improving the mechanical strength and thermal stability of the coating. Notably, the covalent bond energy of the Si-O bond is as high as 425 kJ / mol, far higher than that of CC and CO bonds, providing the material with excellent thermodynamic stability and chemical inertness, improving the stress relief ability and durability of the coating while increasing strength.

[0034] Sulfonic acid compounds are introduced into organopolysiloxane modified acrylic resins through copolymerization, such as Figure 3 As shown. In the present invention, the sulfonic acid group (-SO3H) of sodium α-olefin sulfonate contains three oxygen atoms: one is directly connected to hydrogen (-OH), and the other two are bonded to sulfur atoms in the form of double bonds or single bonds. In the aqueous dispersion stage, the sodium sulfonate group in the long-chain olefin sodium sulfonate can be fully dispersed in the aqueous environment. The hydrophobic long-chain olefin tail contained in its molecular structure tends to interact hydrophobically with the acrylic resin segment and the polysiloxane segment, while the hydrophilic sulfonic acid group (-SO3-) is arranged toward the aqueous phase, thereby forming a stable micellar structure. As an isoelectronic form of carboxylic acid, the -SO3- group of sulfonic acid not only has strong electronegativity and polarity, but also can significantly enhance its dissociation ability and hydrophilicity through inductive effect and resonance effect. This characteristic gives it good aqueous dispersibility. During the subsequent curing process, as the solvent water gradually evaporates, the hydroxyl groups on the polysiloxane segments undergo a condensation reaction with the terminal functional groups of the silane coupling agent KH-570 in the acrylic resin, gradually building a dense three-dimensional cross-linked network. Due to their spatial distribution characteristics in the dispersed state, the -SO3- groups are partially embedded in this cross-linked network, forming an anchoring effect, which stabilizes the sulfonic acid groups throughout the system and tends to concentrate toward the coating surface during the curing process.

[0035] The present invention is based on polyorganosiloxane-modified acrylic resin. By introducing a functional monomer containing a sulfonic acid group and controlling the dosage, combined with a spraying process, the obtained coating has excellent anti-fog performance, high transparency and mechanical stability. The obtained coating has a water contact angle of 5-6°, a hardness of 2-3H, an adhesion of level 0, and an acid and alkali resistance test of >30h.

[0036] The test methods of the coating films prepared in the examples and comparative examples are as follows: Hardness: GB / T 6739-2006; Adhesion: GB / T 9286-2021; Water resistance: GB / T 1733-1993; Solvent resistance: GB / T 23989-2009; The water contact angle was measured using a contact angle meter.

[0037] Example 1: Preparation of Sodium Sulfonate-Modified Silicon-Based Hybrid Super-Hydrophilic Resin (PASO-1) 19.5 g of isopropyl alcohol and 10.5 g of dipropylene glycol methyl ether were added to a four-necked flask and heated to 83°C. 23.54 g of methyl methacrylate, 4.4 g of hydroxyethyl methacrylate, 3.08 g of acrylic acid, 2.2 g of butyl methacrylate, 6.6 g of styrene, 1.76 g of E-51, 2.42 g of butyl acrylate, and 0.88 g of azobisisobutyronitrile were mixed uniformly and added dropwise to the 83°C mixed solvent using a peristaltic pump within 3 hours. The mixture was kept warm for 4 hours. After 2.5 hours of addition, 2.22 g of γ-methacryloyloxypropyltrimethoxysilane and 0.44 g of azobisisobutyronitrile were added to obtain a silicon-modified epoxy acrylic resin (PA-1).

[0038] 7.75 g of methyltrimethoxysilane, 7.58 g of dimethyldimethoxysilane, 5.54 g of phenyltriethoxysilane, and 3.12 g of KH-560 were added to a three-necked flask and heated to 60°C. 11.68 g of deionized water, 17.19 g of isopropanol, and 0.02 g of acetic acid were mixed evenly and added dropwise to the above mixed solvent over 5 minutes. The reaction was stirred at a constant temperature for 4 hours. The solvent was removed and the material was discharged for use to obtain polyorganosiloxane (S-1).

[0039] The water bath where the four-necked flask was located was cooled to 40°C. S-1 was added to PA-1 and mixed for 30 min. 4.78 g of triethylamine was added and neutralized for 30 min. Then, 105 g of deionized water was added dropwise to the modified polyorganosiloxane-modified acrylic resin at a high-speed disperser at a speed of 1800 r / min to obtain polyorganosiloxane-modified acrylic resin (PAS-1).

[0040] To PAS-1, 100 g of an aqueous solution containing 30 wt.% sodium olefin sulfonate was added, followed by 0.46 g of azobisisobutyronitrile, and the mixture was allowed to react for 60 minutes at 50°C to obtain a sodium sulfonate-modified silicon-based hybrid superhydrophilic antifog resin (PASO-1). The superhydrophilic coating was then applied to a substrate using an applicator and cured at room temperature for 24 hours.

[0041] Example 2: Preparation of Sodium Sulfonate Modified Silicon-Based Hybrid Super-Hydrophilic Resin (PASO-2) 21.0 g of isopropyl alcohol and 12.6 g of dipropylene glycol methyl ether were added to a four-necked flask and heated to 90°C. 14.96 g of methyl methacrylate, 4.4 g of hydroxyethyl methacrylate, 3.08 g of acrylic acid, 7.92 g of butyl methacrylate, 3.96 g of styrene, 1.76 g of E-51, 7.92 g of butyl acrylate, and 0.88 g of azobisisobutyronitrile were mixed uniformly and added dropwise to the mixed solvent at 83°C over 3 hours using a peristaltic pump. The mixture was kept warm for 4 hours. After 2.5 hours of addition, 2.22 g of vinyltriethoxysilane and 0.44 g of azobisisobutyronitrile were added to obtain a silicon-modified epoxy acrylic resin (PA-2).

[0042] 7.11 g of methyltrimethoxysilane, 6.95 g of dimethyldimethoxysilane, 5.08 g of phenyltriethoxysilane, and 2.86 g of KH-560 were added to a three-necked flask and heated to 60°C. 10.04 g of deionized water, 17.22 g of isopropyl alcohol, and 0.02 g of diisopropyl phosphite were mixed evenly and then added dropwise to the above mixed solvent within 5 minutes. The reaction was stirred at a constant temperature for 4 hours. The solvent was removed and the material was discharged for use to obtain polyorganosiloxane (S-2).

[0043] The water bath where the four-necked flask was located was maintained at 60°C. S was added to PA and mixed for 30 minutes. Then, 4.78 g of triethylamine was added and neutralized for 30 minutes. Then, 100 g of deionized water was added dropwise to the modified polyorganosiloxane-modified acrylic resin in a high-speed disperser at a speed of 1800 r / min to obtain polyorganosiloxane-modified acrylic resin (PAS-2).

[0044] To PAS-2, 100 g of an aqueous solution containing 30 wt.% sodium olefin sulfonate was added at 50°C, followed by 0.38 g of azobisisobutyronitrile, and the mixture was allowed to react for 40 minutes to obtain a sodium sulfonate-modified silicon-based hybrid superhydrophilic antifog resin (PASO-2). The superhydrophilic coating was then applied to a substrate using an applicator and cured at room temperature for 24 hours.

[0045] Example 3: Preparation of Sodium Sulfonate Modified Silicon-Based Hybrid Super-Hydrophilic Resin (PASO-3) 13.86 g of isopropyl alcohol and 25.74 g of dipropylene glycol methyl ether were added to a four-necked flask and heated to 75°C. 14.8 g of methyl methacrylate, 2 g of hydroxyethyl methacrylate, 3.2 g of isobornyl methacrylate, 3.08 g of acrylic acid, 7.2 g of butyl methacrylate, 2.28 g of styrene, 1.76 g of E-51, 6.4 g of butyl acrylate, and 0.88 g of azobisisobutyronitrile were mixed uniformly and added dropwise to the mixed solvent at 83°C over 3 hours using a peristaltic pump. The mixture was kept warm for 4 hours. After 2.5 hours of addition, 2.22 g of vinyltrimethoxysilane and 0.44 g of azobisisobutyronitrile were added to obtain a silicon-modified epoxy acrylic resin (PA-3).

[0046] 19.2 g of methyltrimethoxysilane, 8.4 g of dimethyldimethoxysilane, 8.0 g of phenyltriethoxysilane, and 4.4 g of KH-560 were added to a three-necked flask and heated to 60°C. 4.56 g of deionized water, 4.56 g of isopropanol, and 0.02 g of acetic acid were mixed evenly and then added dropwise to the above mixed solvent within 5 minutes. The reaction was stirred at a constant temperature for 4 hours. After the solvent was removed, the material was discharged for use to obtain polyorganosiloxane (S-3).

[0047] The water bath where the four-necked flask was located was cooled to 35°C. S was added to PA and mixed for 30 min. Then, 3.79 g of triethylamine was added and neutralized for 30 min. Then, 105 g of deionized water was added dropwise to the modified polyorganosiloxane-modified acrylic resin at a high-speed disperser at a speed of 1800 r / min to obtain polyorganosiloxane-modified acrylic resin (PAS-3).

[0048] To PAS-3, 100 g of an aqueous solution containing 30 wt.% sodium olefin sulfonate was added at 50°C, followed by 0.44 g of azobisisobutyronitrile, and the mixture was allowed to react for 40 minutes to obtain a sodium sulfonate-modified silicon-based hybrid superhydrophilic antifog resin (PASO-3). The superhydrophilic coating was then applied to a substrate using an applicator and cured at room temperature for 48 hours.

[0049] Example 4: Preparation of Sodium Sulfonate-Modified Silicon-Based Hybrid Super-Hydrophilic Resin (PASO-4) 13.86 g of isopropyl alcohol and 25.74 g of dipropylene glycol methyl ether were added to a four-necked flask and heated to 80°C. 14.08 g of methyl methacrylate, 4.4 g of hydroxyethyl methacrylate, 6.6 g of isobornyl methacrylate, 3.08 g of acrylic acid, 7.2 g of butyl methacrylate, 2.28 g of styrene, 1.76 g of E-51, 3.2 g of butyl acrylate, and 0.88 g of azobisisobutyronitrile were mixed uniformly and added dropwise to the mixed solvent at 83°C over 3 hours using a peristaltic pump. The mixture was kept warm for 4 hours. After 2.5 hours of addition, 2.22 g of vinyltrimethoxysilane and 0.44 g of azobisisobutyronitrile were added to obtain a silicon-modified epoxy acrylic resin (PA-4).

[0050] 19.2 g of methyltrimethoxysilane, 8.4 g of dimethyldimethoxysilane, 8.0 g of phenyltriethoxysilane, and 4.4 g of KH-560 were added to a three-necked flask and heated to 60°C. 4.56 g of deionized water, 4.56 g of isopropanol, and 0.02 g of acetic acid were mixed evenly and then added dropwise to the above mixed solvent within 5 minutes. The reaction was stirred at a constant temperature for 4 hours. After the solvent was removed, the material was discharged for use to obtain polyorganosiloxane (S-4).

[0051] The water bath where the four-necked flask was located was cooled to 45°C. S was added to PA and mixed for 30 min. Then, 3.79 g of triethylamine was added and neutralized for 30 min. Then, 105 g of deionized water was added dropwise to the modified polyorganosiloxane-modified acrylic resin at a high-speed disperser at a speed of 1800 r / min to obtain polyorganosiloxane-modified acrylic resin (PAS-4).

[0052] To PAS-4, 100 g of an aqueous solution containing 30 wt.% sodium olefin sulfonate was added at 50°C, followed by 0.44 g of azobisisobutyronitrile, and the mixture was allowed to react for 40 minutes to obtain a sodium sulfonate-modified silicon-based hybrid superhydrophilic antifog resin (PASO-4). The superhydrophilic coating was then applied to a substrate using an applicator and cured at room temperature for 48 hours.

[0053] Comparative Example 1: Preparation of Silicon-Based Hybrid Resin (PASO-5) without Addition of Sodium Sulfonate Modification Silylated polyacrylate resin (PA-5) was prepared using the same usage, dosage and process as in Example 1.

[0054] Polyorganosiloxane (S-5) was prepared using the same usage, dosage and process as in Example 1.

[0055] Mix PA-5 and S-5 to create a silicone-based hybrid resin (PASO-5) without sodium sulfonate modification. Apply to a substrate using an applicator and cure at room temperature for 24 hours.

[0056] Comparative Example 2: A hydrophilic polymer anti-fog coating (PASO-6) Clean the glass substrate with three equal parts of deionized water, acetone, and ethanol, blow dry with nitrogen, and set aside. Add 0.1 part of aqueous hydrogen peroxide to 20 parts of concentrated sulfuric acid, for a total weight of 100 g. After mixing thoroughly, place the substrate in the solution. Boil the solution in hot water for 0.1 min, remove, rinse with deionized water, and blow dry with nitrogen.

[0057] Dissolve the silane coupling agent in mixed solvent A to prepare a 0.1 wt.% solution. Place the pretreated substrate in the silane solution and immerse it at 25°C for 36 hours. Mixed solvent A consists of 50 parts anhydrous ethanol, 50 parts deionized water, and 0.1 part acetic acid, with a total solution weight of 100 g.

[0058] 50 parts of 2-tert-butylaminoethyl methacrylate and 1 part of photoinitiator benzophenone were mixed in deionized water to prepare a solution with a mass fraction of 0.1 wt.%. The total weight of the solution was 10 g. The solution was evenly coated on a substrate treated with a silane solution by brushing. The substrate was exposed to ultraviolet light at 1 W / cm2 for 5 seconds to initiate polymerization, forming a hydrophilic anti-fog coating.

[0059] Comparative Example 3: Superhydrophilic coating containing SiO2 nanoparticles (PASO-7) An aqueous solution composed of 25% methyl methacrylate, 30% butyl acrylate, 5% methacrylic acid, 5% hydroxyethyl methacrylate, 1.5% vinyltriethoxysilane and 1% emulsifier (a mixture of OP-10 and C0436) was mixed and ultrasonically stirred at 30°C for 1.5 h to obtain pre-emulsion A. Aqueous solution B consisting of 1.8% emulsifier (a mixture of OP-10 and C0436) and 0.7% sodium bicarbonate pH buffer was prepared; aqueous solution C containing 1.8 wt% ammonium persulfate initiator was prepared; pre-emulsion A, aqueous solution B, and aqueous solution C were reacted in a ratio of 20:9:5 to obtain a self-crosslinking modified acrylate emulsion D. 15% of pre-emulsion A and 15% of aqueous solution C were added to aqueous solution B as the bottom material of the reactor. The remaining pre-emulsion A and aqueous solution C were slowly added dropwise to the reactor over 80-90 minutes. The temperature was controlled at 75°C, the stirring speed was 400 rpm, and the reaction time was 2 hours. A silica aqueous dispersion with a particle size of about 10 nm and a self-crosslinking modified acrylic emulsion D were mixed in a ratio of 15:1, wherein the mass ratio of vinyltriethoxysilane to nano-silica was 1:300, and 2% sodium dodecylbenzenesulfonate was added. Ultrasonic stirring was performed for 40 min to obtain a superhydrophilic coating E.

[0060] Figure 4The infrared spectra of the materials obtained in Example 1 and Comparative Examples 1, 2, and 3 are shown. Comparison with Comparative Examples 1, 2, and 3 reveals a significant shift in the -OH stretching vibration peak at 3436 cm⁻¹ within the composite material. After addition of the sodium sulfonate solution and curing, the hydroxyl stretching vibration peak significantly weakens and nearly disappears, confirming the formation of a hydrogen-bonded network within the material. The absorption peaks at 2920 cm⁻¹ and 2858 cm⁻¹ correspond to the asymmetric and symmetric stretching vibration modes of the CH₂ group, while the peak at 1382 cm⁻¹ originates from the rocking vibration characteristic of the CH₂ group.

[0061] Table 1 shows the data obtained after testing Examples 1-4 and Comparative Examples 1-3. The hardness of Examples 1-4 and Comparative Examples 1 and 3 all reached or exceeded 2H, while Comparative Example 2 achieved a hardness of HB. The present invention incorporates a high content of polyorganosiloxane, which, through the interaction of multiple functional groups, achieves stable bonding within the resin and between the resin and the substrate surface, effectively improving the coating hardness. Comparative Example 2, which uses only an organic polymer to achieve a hydrophilic effect, struggles to maintain a consistent hardness.

[0062] The adhesion of Examples 1-4 was grade 0, while that of Comparative Examples 1-2 was grade 1, and that of Comparative Example 3 was grade 2, significantly inferior. This indicates that the Examples significantly outperform the Comparative Examples in terms of tight adhesion between the coating and the substrate. The water contact angles of Examples 1-4 were all close to 5°, with Comparative Examples 1-2 having significantly higher values.

[0063] As shown in Table 1, the coating film prepared in the embodiment of the present invention has a water contact angle of 5°~6.0°, an adhesion of level 0, good thermal stability, and exhibits excellent superhydrophilic and anti-fog properties, and is suitable for anti-fog treatment of substrates such as optical devices and automotive glass.

[0064] Table 1 Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Appearance transparent transparent transparent transparent transparent transparent transparent Hardness / H 2 3 2 2 2 1 2 Adhesion / Grade 0 0 0 0 1 1 2 <![CDATA[Thermal stability T 5% / ℃]]> 165 168 171 167 160 155 158 Water contact angle / ° 5.7 6.0 5.3 5.7 62.0 10.1 5.0 Figure 5 The hot steam anti-fog test of Example 1 and Comparative Examples 1, 2, and 3 is shown in the figure. The left side of the red line is the uncoated substrate, and the right side is the coated substrate with different sodium sulfonates added. The uncoated area quickly fogged during the test, and obvious water vapor condensation appeared on the surface; Comparative Examples 1, 2, and 3 showed obvious water mist, while the surface of Example 1 had almost no obvious fogging, and the surface remained clear with high transmittance. This is attributed to the fact that the sulfonic acid group in the present invention significantly enhances its dissociation ability and hydrophilicity. Due to its spatial distribution characteristics in the dispersed state, the -SO3- group is partially synergistically embedded in the cross-linked network structure. The sulfonic acid group is stably distributed in the system as a whole through anchoring, which effectively improves the anti-fog ability of the substrate.

[0065] Combined with Table 1 and Figure 4 and 5Tests demonstrate that this invention overcomes existing issues such as the difficulty in balancing mechanical strength and hydrophilicity, uneven dispersion of inorganic nanoparticles, and a significant decrease in super-hydrophilicity at low and high temperatures. Test results demonstrate that the coating obtained by this invention combines excellent anti-fog properties, high transparency, and mechanical stability. The resulting coating has a water contact angle of 5-6°, a hardness of 2-3 hours, a grade 0 adhesion, and an acid and alkali resistance test of >30 hours.

[0066] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a sodium sulfonate-modified silicon-based hybrid super-hydrophilic anti-fog resin, characterized in that The process includes the following steps: (1) In parts by weight, 0.1-40 parts of organosilicon monomer are heated to 40-80°C; 0.02-0.08 parts of acidic catalyst are uniformly mixed with 0.5-16 parts of deionized water and 0.5-16 parts of cosolvent A, and the mixture is added dropwise to the organosilicon monomer and kept warm for 4-12 hours; after the end of the heat preservation, the cosolvent is removed to obtain polyorganosiloxane; (2) In parts by weight, 50-100 parts of cosolvent B are heated to 70-90°C; 7-15 parts of hydroxyl-containing acrylate monomers, 2-12 parts of acrylic acid and / or methacrylic acid, 30-55 parts of acrylate monomers and / or methacrylate monomers, 6-21 parts of benzene ring-containing monomers, 3-8 parts of double-bond siloxanes, and 3-8 parts of initiator A are mixed uniformly and then added dropwise to the cosolvent at a uniform rate. The addition is completed within 2-4 hours. After keeping the mixture warm for 3-5 hours, the mixture is cooled to below 60°C, 1-10 parts of an alkaline neutralizer is added to adjust the degree of neutralization, 15-40 parts of polyorganosiloxane are added, the mixture is mixed uniformly at 40-60°C, and the mixture is dispersed in 50-300 parts of deionized water under stirring to prepare a polyorganosiloxane-modified acrylate aqueous dispersion; (3) The sodium sulfonate compound and deionized water are mixed in a mass ratio of 1:0.5-4, and stirred until completely dissolved to obtain a sodium sulfonate aqueous solution; the polyorganosiloxane modified acrylate aqueous dispersion and the sodium sulfonate aqueous solution are blended in a mass ratio of 1:0.1-0.5, 1-5 parts by weight of initiator B are added and stirred for reaction for 30-60 minutes to obtain a sulfonic acid group-modified silicon-based hybrid super hydrophilic anti-fog resin.

2. The method for preparing the sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin according to claim 1, wherein: The organosilicon monomer is at least two of methyltrimethoxysilane, propyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, dimethyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane and γ-glycidoxypropylmethyldiethoxysilane; the acidic catalyst is one or more of hydrochloric acid, phosphoric acid, acetic acid, oxalic acid, diisopropyl phosphite, sodium diethyl phosphite and sodium methylphosphonate; the cosolvent A is one or more of ethylene glycol, propylene glycol, isopropyl alcohol, n-butanol, isobutanol, propylene glycol methyl ether, propylene glycol propyl ether, ethylene glycol butyl ether, dipropylene glycol methyl ether and dipropylene glycol butyl ether.

3. The method for preparing the sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin according to claim 1, wherein: The acrylic acid ester monomer is one or more of acrylic acid ester, ethyl acrylate, butyl acrylate, hexyl acrylate and octyl acrylate; the methacrylic acid ester monomer is one or more of methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate and octyl methacrylate; the benzene ring-containing monomer is one or more of styrene and methyl styrene; the cosolvent B is one or more of ethylene glycol, propylene glycol, isopropyl alcohol, n-butanol, isobutyl alcohol, propylene glycol methyl ether, propylene glycol propyl ether, ethylene glycol butyl ether, dipropylene glycol methyl ether and dipropylene glycol butyl ether; the alkaline neutralizer is one or more of ammonia water, diethanolamine, triethanolamine, triethylamine, N, N-dimethylethanolamine, 2-amino-2-methyl-propanol and tetramethylammonium hydroxide; the initiator A is one or more of azobisisobutyronitrile, azobisisoheptylonitrile, benzoyl peroxide and cumene hydroperoxide.

4. The method for preparing the sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin according to claim 1, wherein: The hydroxyl-containing acrylic acid ester monomer is one or more of hydroxyethyl acrylate, hydroxypropyl acrylate and hydroxybutyl acrylate; the hydroxyl-containing methacrylic acid ester monomer is one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate and hydroxybutyl methacrylate.

5. The method for preparing the sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin according to claim 1, wherein: The double bond-containing organosilicon monomer is one or more of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, γ-methacryloxypropyltrimethoxysilane and vinyltriacetoxysilane.

6. The method for preparing the sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin according to claim 1, wherein: Before adding initiator A in step (2), 0 to 8 parts by weight of epoxy resin is also added; the epoxy resin is one or more of epoxy resin E-03, epoxy resin E-06, epoxy resin E-12, epoxy resin E-20, epoxy resin E-21, epoxy resin E-44, epoxy resin E-51, and epoxy resin E-54.

7. The method for preparing the sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin according to claim 1, wherein: The sodium sulfonate is one or more of sodium α-olefin sulfonate, sodium allyl sulfonate, sodium α-olefin sulfonate, sodium allyl sulfonate, 2-acrylamide-2-methylpropane sulfonic acid, sodium vinyl sulfonate, and sodium styrene sulfonate; and the initiator B is one or more of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, and cumene hydroperoxide.

8. The method for preparing the sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin according to claim 1, wherein: The solvent removal in step (1) is carried out at 40-60°C; The stirring in step (3) until the mixture is completely dissolved is carried out at 35-60° C. for 1-4 hours until the mixture is completely dissolved.

9. A sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin, characterized in that The compound is prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the sulfonic acid group-modified silicon-based hybrid super-hydrophilic anti-fog resin according to claim 9 in optical devices, automotive glass or medical equipment.

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