Nano metal oxide modification method, modified nano titanium dioxide particles and application of modified nano titanium dioxide particles

Abstract

The invention belongs to the technical field of materials, and particularly relates to a nano metal oxide modification method, modified nano titanium dioxide particles and application thereof. The method comprises the following steps: S1, preparing nano titanium dioxide particles by adopting a hydrothermal method; s2, dispersing nano titanium dioxide particles in a solvent to prepare a nano titanium dioxide particle dispersion liquid; s3, adjusting the nano titanium dioxide particle dispersion liquid to an acidic or neutral condition, dropwise adding a metal modifier into the nano titanium dioxide particle dispersion liquid, carrying out stirring reaction, and carrying out vacuum drying to obtain modified nano titanium dioxide particles; the metal modifier is a zirconate coupling agent. The modified nano titanium dioxide particles provided by the invention are applied to the optical cement, so that the optical cement not only has good optical performance, but also has outstanding light resistance.

Description

Technical Field

[0001] This invention belongs to the field of materials technology, specifically relating to a method for modifying nano-metal oxides, modified nano-titanium dioxide particles, and their applications. Background Technology

[0002] In the field of optical resin composition research and development, to achieve high refractive indices, existing technologies commonly employ the addition of high-refractive-index nanoparticles (such as ZrO2 and TiO2) to organic materials, effectively increasing the refractive index to 1.66 or even above 1.70. However, in practical industrial applications, this technique has significant drawbacks: the van der Waals forces between hydroxyl groups on the TiO2 particle surface and the formation of hydrogen bonds transform the repulsive forces between powders into attractive forces, thus enhancing the aggregation of TiO2 particles. Furthermore, due to the strong photochemical activity of titanium dioxide, when TiO2 is exposed to light (especially ultraviolet light), valence band electrons are excited to the conduction band, forming electron-hole pairs. These highly reactive electrons and holes can react with water or oxygen to generate hydroxyl radicals and superoxide anions with strong oxidizing capabilities, leading to problems such as yellowing and aging. This directly results in a decline in key performance characteristics of the optical resin composition, including light transmittance, mechanical properties, and weather resistance. These technical deficiencies severely restrict the quality improvement and application expansion of high-refractive-index optical resin compositions in high-end optical fields (such as optical lenses and display devices). Therefore, titanium dioxide needs to undergo surface modification before use.

[0003] Currently, the commonly used modification method is surface modification with coupling agents. Some functional groups in the coupling agent molecule can react with the active groups on the surface of nano-TiO2 powder to form strong chemical bonds, thus coating the surface of titanium dioxide with the coupling agent. This results in the modified TiO2 product exhibiting good dispersion performance in organic materials. Other functional groups can undergo certain chemical reactions or physical entanglement with organic polymers, creating "molecular bridges" with special functions between nano-TiO2 and the organic medium, thereby improving the overall performance of the nanocomposite material. However, it should be noted that existing surface modification techniques with coupling agents can only solve the problems of TiO2 nanoparticle aggregation and interfacial bonding, but cannot effectively regulate the photochemical activity of TiO2 nanoparticles. Therefore, they cannot solve the problems of yellowing and aging of organic polymers caused by photocatalytic activity. Therefore, there is an urgent need to develop a surface modification method for TiO2 nanoparticles that can effectively solve the problem of yellowing of organic polymers caused by photocatalytic activity while ensuring the dispersion and refractive index improvement of TiO2 nanoparticles, in order to meet the performance requirements of high-end optical resin compositions. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for modifying nano-metal oxides, modified nano-titanium dioxide particles, and their applications.

[0005] The technical solution provided by this invention is as follows: A method for modifying nano-metal oxides includes the following steps: S1: Nano-sized titanium dioxide particles were prepared using a hydrothermal method; S2: Prepare a nano-titanium dioxide particle dispersion by dispersing nano-titanium dioxide particles in a solvent; S3: Adjust the nano-titanium dioxide particle dispersion to acidic or neutral conditions, add a metal modifier dropwise to the nano-titanium dioxide particle dispersion, stir the reaction, and vacuum dry to obtain modified nano-titanium dioxide particles. The central metal atom of the metal modifier is a zirconate coupling agent.

[0006] Furthermore, the central metal atom of the metal modifier is Zr, and it contains at least one saturated or unsaturated alkoxy hydrolysis group.

[0007] Furthermore, the metal modifier is selected from structures such as Zr(OR1)p(R2)q, p+q=4, p>0; R1 is C 1-20 A saturated or unsaturated alkyl group, wherein R2 is C 1-20 Saturated or unsaturated alkyl groups, C 1-20 The alkyl-substituted phenyl group; the alkylene portion of the substituent represented by R2 may be broken by an N atom, an O atom, an ester bond, an acyl group, a sulfonate bond, a phosphate bond, a pyrophosphate bond, a sulfonic acid acyloxy group, or a sulfonic acid acyloxy group, and the H at the terminal position of R2 may be replaced by a reactive group.

[0008] Based on the above technical solution: the alkyl group represented by R1 can be hydrolyzed to form a strong Zr-O-Ti bond on the surface of the nano-titanium dioxide particles. This allows for the use of higher bond energy zirconium-oxygen bonds (Zr-O) to achieve a dense surface coating layer on the titanium dioxide nanoparticles, thereby inhibiting the photocatalytic activity of titanium dioxide. The alkylene portion of the substituent represented by R2 can be broken by strong polar groups such as N atoms, O atoms, ester bonds, acyl groups, sulfonate bonds, phosphate ester bonds, pyrophosphate ester bonds, sulfonyloxy groups, and sulfonyloxy groups. This forms a strong anchoring end that stably binds to the TiO2 surface, ensuring that the surface-coated alkyl chain will not detach from the TiO2 surface even under harsh environments, further strengthening the interfacial connection. The reactive group at the end of R2 allows the modified nano-titanium dioxide particles to be suitable for different application scenarios, enhancing the crosslinking density after doping with different types of organic polymers such as epoxy resin, rubber, and acrylic resin, thus possessing universality.

[0009] Furthermore, the C 1-20 The saturated or unsaturated alkyl group is selected from C14 groups whose terminal alkyl groups are substituted with or unsubstituted with an alkenyl group. 1-6 Saturated alkyl groups; C1-6 Saturated alkyl groups, including, but not limited to, methyl, ethyl, propyl or butyl.

[0010] Furthermore, the reactive group is selected from amino, hydroxy, (meth)acrylate, carboxyl, epoxy, vinyl, or mercapto groups.

[0011] As a preferred technical solution, p is 1 and q is 3.

[0012] Further examples of the metal modifier include, but are not limited to, isopropoxytris(isostearoyl)zirconia, isopropoxytris(dodecylbenzenesulfonyl)zirconia, isopropoxytris(dioctylphosphoyl)zirconia, isopropoxytris(dioctylpyrophosphoyl)zirconia, neoalkoxytris(dioctylpyrophosphoyl)zirconia, neoalkoxytris(neodecanyl)zirconia, neoalkoxytris(p-aminophenoxy)zirconia, neoalkoxytris(m-aminophenoxy)zirconia, neopentoxy(diallyl)oxytris(dioctylpyrophosphoyl)zirconia, neopentoxy(diallyl)oxytris(N-ethylenediamine)ethylzirconia, neopentoxy(diallyl)oxytris(neodecanyl)zirconia, neopentoxy(diallyl)oxytris(dioctylphosphoyl)zirconia, neopentoxy(diallyl)oxytris(dodecylbenzenesulfonyl)zirconia, neopentoxy(di-) Allyl)oxytris(methacryloyl)zirconia, neopentoxy(diallyl)oxytris(acryloyl)zirconia, neoalkoxy(trinedecyl)zirconia, neoalkoxytris(dodecylbenzenesulfonyl)zirconia, neopentoxy(diallyl)oxytris(N-ethylenediamino)ethylzirconia, neopentoxy(diallyl)oxytris(m-aminophenoxy)zirconia, neoalkoxytris(methacryloyl)zirconia, neoalkoxytris(dioctylphosphoyl)zirconia, neoalkoxytris(dioctylpyrophosphoyl)zirconia, neoalkoxytris(nedecyl)zirconia, neoalkoxytris(ethylenediamino)ethylzirconia, isopropoxytris(vinylethoxy)zirconia, dinepentoxy(diallyl)oxydi-p-aminobenzoylzirconia, dinepentoxy(diallyl)oxydi(3-mercapto)propionatezirconia, the above can be found from Kenrich The KZ and NZ series are commercially available from Petrochemicals or from Nanjing Pinning Coupling Agent Co., Ltd.

[0013] The size of the nano-titanium dioxide particles is 10-1000 nm. Preferably, the size of the nano-titanium dioxide particles is 10-500 nm; more preferably, the size of the nano-titanium dioxide particles is 10-100 nm.

[0014] The weight ratio of the nano-titanium dioxide particles to the metal modifier is 1:(0.01-0.2).

[0015] The hydrothermal method is as follows: a titanium source is used as a precursor, and water, an organic solvent, or a mixture of the two are used as the reaction medium. The mixture is stirred evenly to obtain a precursor solution. After adjusting the pH with an acidic solution, the solution is placed in a polytetrafluoroethylene high-pressure reactor and reacted at 150–240°C for 18–24 hours. The precipitate obtained after centrifuging the suspension is washed with water, dried, and ground to obtain crystalline nano-titanium dioxide.

[0016] Furthermore, the polytetrafluoroethylene high-pressure reactor adopts a gradient heating method. In the initial stage, the temperature is raised to 120~180℃ and kept at a constant temperature for 4~6 hours to promote the formation of crystal nuclei. Then, the temperature is raised to 200~240℃ and kept at a constant temperature for 14~20 hours to promote the regularity of crystal morphology and the denser and more stable crystal lattice structure.

[0017] Furthermore, the titanium source is selected from one or more of titanate esters, titanium tetrachloride, and titanium sulfate. Examples of titanate esters include, but are not limited to, tetrabutyl titanate, methyl titanate, ethyl titanate, n-propyl titanate, and isopropyl titanate.

[0018] The amount of the metal modifier added is 1%-20% of the mass of nano-titanium dioxide; the solvent in the nano-titanium dioxide particle dispersion is selected from any one or more combinations of ethanol, chloroform, ethyl acetate, isopropanol, ethylene glycol, cyclohexane, and acetone; the mass fraction of titanium dioxide in the nano-titanium dioxide particle dispersion is 15%-40%.

[0019] Furthermore, adding the metal modifier at 1%-10% or 1%-5% of the mass of nano-titanium dioxide can still achieve good modification effects.

[0020] Furthermore, the specific steps for modifying nano-metal oxides are as follows: S1: Disperse the titanium source in anhydrous ethanol at a mass ratio of 1:1 to 1:10, and slowly add it dropwise to deionized water at a mass ratio of 30 to 40 times that of the titanium source to obtain a precursor solution; after adjusting the pH to 3 or below with an acidic solution, put it into a polytetrafluoroethylene high-pressure reactor and react at 120 to 240°C for 18 to 24 hours to obtain crystalline nano-titanium dioxide; S2: Mix crystalline nano-titanium dioxide with solvent at a mass ratio of 1:2.5 to 1:6, and then sonicate and stir to obtain a dispersion of nano-titanium dioxide particles; S3: Adjust the pH of the nano-titanium dioxide particle dispersion to 5-7, mix evenly, add metal modifier dropwise, react at 45℃-90℃ for 1-3h, preferably 1-2h, and vacuum dry to obtain nano-titanium dioxide particle powder.

[0021] The solvent in step S2 is selected from any one or more combinations of ethanol, chloroform, ethyl acetate, isopropanol, ethylene glycol, cyclohexane, and acetone.

[0022] The present invention also provides modified nano-titanium dioxide particles prepared by the above method.

[0023] Secondly, the present invention also provides an application of modified nano-titanium dioxide particles for preparing ink materials or adhesives in display devices.

[0024] Thirdly, the present invention provides a high-refractive-index optical adhesive comprising modified nano-titanium dioxide particles obtained by the above-described nano-titanium dioxide modification method, unsaturated resin, acrylate monomer, photoinitiator, solvent, and other additives.

[0025] The metal modifier provided in this application has strong adsorption capacity and can form strong Zr-O-Ti bonds on the surface of nano-titanium dioxide particles, thereby tightly bonding zirconium metal to the surface of titanium dioxide particles. By controlling the modification conditions (pH, reaction rate, time), the titanium dioxide coating layer can be effectively controlled, forming a dense coating layer on the surface of nano-titanium dioxide particles, which reduces the ultraviolet light reaching the titanium dioxide particles. Compared with other coupling agents, the modification method of this application inhibits the photocatalytic activity of titanium dioxide while using high-refractive-index zirconium ions to fill the lattice of titanium dioxide nanoparticles, increasing the atomic packing density, significantly improving the compactness, stability and high refractive index of the material, and finally obtaining a titanium dioxide-zirconium coated material with good light resistance and dispersion stability.

[0026] On the other hand, when applied to optical resin compositions, the reactive groups on the surface of nano-titanium dioxide can react with the resin, improving the compatibility between the nano-titanium dioxide particles and the resin. At the same time, the nano-titanium dioxide particles are stably bonded to the resin matrix through chemical bonds, so that the nano-titanium dioxide particles form a uniform network in the resin, effectively avoiding the effects of nano-titanium dioxide particle migration and interface peeling, and improving its applicability in different application scenarios such as ink materials and adhesives. Detailed Implementation

[0027] The principles and features of the present invention are described below. The embodiments given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0028] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0029] Example 1 of preparation of modified nano-titanium dioxide particles: S1: Mix 50g of isobutyl titanate and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 1500ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Add 1mol / L hydrochloric acid solution to adjust the pH to 3, put it into a polytetrafluoroethylene high-pressure reactor, and react at 130℃ for 18 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry, grind, and obtain 10.2g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add acetic acid solution with a concentration of 1 mol / L to the nano-titanium dioxide particle dispersion, adjust the pH to 5, mix well, add 1g of neoalkoxytris(neodecanoyl)zirconia ester dropwise, react at 50℃ for 2h, and vacuum dry to obtain modified nano-titanium dioxide particles.

[0030] Example 2 of preparation of modified nano-titanium dioxide particles: S1: Mix 50g of isobutyl titanate and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 1500ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Put it into a polytetrafluoroethylene high-pressure reactor and react at 130℃ for 18 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry, grind, and obtain 10.5g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add acetic acid solution with a concentration of 1 mol / L to the nano-titanium dioxide particle dispersion, adjust the pH to 5, mix well, add 1g of neoalkoxytris(neodecanoyl)zirconia ester dropwise, react at 50℃ for 2h, and vacuum dry to obtain modified nano-titanium dioxide particles.

[0031] Example 3 of preparation of modified nano-titanium dioxide particles: S1: Mix 50g of isobutyl titanate and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 1500ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Add 1mol / L hydrochloric acid solution to adjust the pH to 3, put it into a polytetrafluoroethylene high-pressure reactor, and react at 130℃ for 18 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry, grind, and obtain 10.2g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add acetic acid solution with a concentration of 1 mol / L to the nano-titanium dioxide particle dispersion, adjust the pH to 5, mix well, add 1g of neoalkoxytris(dioctylpyrophosphoryloxy)zirconia ester, react at 50℃ for 2h, and vacuum dry to obtain modified nano-titanium dioxide particles.

[0032] Example 4: Preparation of modified nano-titanium dioxide particles S1: Mix 50g of isobutyl titanate and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 30ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Add 1mol / L hydrochloric acid solution to adjust the pH to 3, and put it into a polytetrafluoroethylene high-pressure reactor. First, react at 130℃ for 4 hours, and then raise the temperature to 200℃ for 14 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry, and grind to obtain 11.1g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add acetic acid solution with a concentration of 1 mol / L to the nano-titanium dioxide particle dispersion, adjust the pH to 5, mix well, add 1g of neoalkoxytris(dioctylpyrophosphoryloxy)zirconia ester, react at 50℃ for 2h, and vacuum dry to obtain modified nano-titanium dioxide particles.

[0033] Example 5 of preparation of modified nano-titanium dioxide particles: S1: Mix 50g of titanium tetrachloride and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 1500ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Add 1mol / L hydrochloric acid solution to adjust the pH to 3, put it into a polytetrafluoroethylene high-pressure reactor, and react at 130℃ for 18 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry, grind, and obtain 10.6g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add acetic acid solution with a concentration of 1 mol / L to the nano-titanium dioxide particle dispersion, adjust the pH to 5, mix evenly, add 1g of isopropoxytris(isostearoyl)zirconia ester dropwise, react at 50℃ for 2h, and vacuum dry to obtain modified nano-titanium dioxide particles.

[0034] Example 6: Preparation of modified nano-titanium dioxide particles S1: Mix 50g of titanium tetrachloride and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 1500ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Put it into a polytetrafluoroethylene high-pressure reactor and react at 130℃ for 18 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry, grind, and obtain 10g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add hydrochloric acid to the nano-titanium dioxide particle dispersion to adjust the pH to 5. After mixing evenly, add 1g of isopropoxytris(dodecylbenzenesulfonyl)zirconia ester dropwise. React at 50℃ for 2h and then vacuum dry to obtain modified nano-titanium dioxide particles.

[0035] Example 7: Preparation of modified nano-titanium dioxide particles S1: Mix 50g of titanium tetrachloride and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 1500ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Add 1mol / L hydrochloric acid solution to adjust the pH to 3, put it into a polytetrafluoroethylene high-pressure reactor, and react at 130℃ for 18 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry, grind, and obtain 10.6g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add acetic acid solution with a concentration of 1 mol / L to the dispersion of nano-titanium dioxide particles, adjust the pH to 5, mix well, add 1g of isopropoxytris(dodecylbenzenesulfonyl)zirconia ester dropwise, react at 50℃ for 2h, and vacuum dry to obtain modified nano-titanium dioxide particles.

[0036] Example 8: Preparation of modified nano-titanium dioxide particles S1: Mix 50g of titanium tetrachloride and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 1500ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Add 1mol / L hydrochloric acid solution to adjust the pH to 3, put it into a polytetrafluoroethylene high-pressure reactor, and react at 130℃ for 18 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry, grind, and obtain 10.6g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add acetic acid solution with a concentration of 1 mol / L to the dispersion of nano-titanium dioxide particles, adjust the pH to 5, mix evenly, add 0.5 g of isopropoxytris(dodecylbenzenesulfonyl)zirconia ester dropwise, react at 50℃ for 2 h, and vacuum dry to obtain modified nano-titanium dioxide particles.

[0037] Example 9 of preparation of modified nano-titanium dioxide particles: S1: Mix 50g of isobutyl titanate and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 1500ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Add 1mol / L hydrochloric acid solution to adjust the pH to 3, put it into a polytetrafluoroethylene high-pressure reactor, and react at 130℃ for 4 hours. Then raise the temperature to 220℃ and react at 220℃ for 14 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry it, grind it, and obtain 11g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add acetic acid solution with a concentration of 1 mol / L to the dispersion of nano-titanium dioxide particles, adjust the pH to 5, mix well, add 0.1 g of isopropoxytris(dodecylbenzenesulfonyl)zirconia ester dropwise, react at 50℃ for 2 h, and vacuum dry to obtain modified nano-titanium dioxide particles.

[0038] Comparative Example 1: Preparation of Modified Nano-Titanium Dioxide Particles S1: Mix 50g of isobutyl titanate and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 30ml of deionized water. After titration, continue stirring for 30-40min to obtain a precursor solution; put it into a polytetrafluoroethylene high-pressure reactor and react at 130℃ for 18 hours to obtain 10.5g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add acetic acid solution with a concentration of 1 mol / L to the dispersion of nano-titanium dioxide particles, adjust the pH to 5, mix evenly, add 1g of silane coupling agent 3-(methacryloyloxy)propyltrimethoxysilane, react at 50℃ for 2h, and vacuum dry to obtain modified nano-titanium dioxide particles.

[0039] Comparative Example 2: Preparation of Modified Nano-Titanium Dioxide Particles S1: Mix 50g of titanium tetrachloride and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 1500ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Put it into a polytetrafluoroethylene high-pressure reactor and react at 130℃ for 18 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry, grind, and obtain 10g of crystalline nano titanium dioxide. S2: Disperse 5g of crystalline nano-titanium dioxide in 20ml of chloroform, sonicate for 25min, stir for 25min to obtain a nano-titanium dioxide particle dispersion. S3: Add acetic acid solution with a concentration of 1 mol / L to the nano titanium dioxide particle dispersion, adjust the pH to 5, mix evenly, add 1g of isopropyl tris(dodecylbenzenesulfonyl) titanate, react at 50℃ for 2h, and vacuum dry to obtain nano titanium dioxide particle powder.

[0040] Comparative Example 3: Preparation of Unmodified Nano-Titanium Dioxide Particles S1: Mix 50g of titanium tetrachloride and 75g of anhydrous ethanol, stir evenly at 20℃, and titrate to 1500ml of deionized water. After titration, continue stirring for 30min to obtain a precursor solution. Put the solution into a polytetrafluoroethylene high-pressure reactor and react at 130℃ for 18 hours. After centrifuging the suspension, wash the precipitate twice with deionized water, dry, and grind to obtain 10g of crystalline nano titanium dioxide.

[0041] Performance testing: Aging resistance test of nano-titanium dioxide particles: Under room temperature ultraviolet light irradiation, the photocatalytic activity of the modified nano-titanium dioxide particles prepared in Examples 1-9 for Rhodamine B (RhB) degradation was tested. Specific steps: 0.1 g of ground titanium dioxide particle powder was added to 1 mL of ethanol solution and dispersed uniformly. The absorbance (C0) was measured at the maximum absorption wavelength of Rhodamine B (556 nm) using a UV-Vis spectrophotometer. Then, the dispersion was added to 50 mL of Rhodamine B ethanol solution (10 μg / L), stirred for 30 minutes in a dark room, and then added to a PCX50C multichannel photochemical reactor. The rotation speed of the photocatalytic reactor was set to 200 rpm, and the reaction temperature was set to 25°C. A 5-watt LED device (365 nm) was used in a circular motion mode to avoid uneven light reception caused by inconsistent light output from different emitters. After 60 minutes, the sample was filtered through a 0.45 μm polytetrafluoroethylene filter membrane, and then its absorbance (denoted as C) was measured at the maximum absorption wavelength (556 nm) of Rhodamine B using a UV-Vis spectrophotometer. The n value (C / C0) was calculated, with a larger n value indicating better aging resistance. Particle size was measured using the DLS method, and refractive index was measured using a refractometer. The experimental results are shown in Table 1 below: Table 1 As can be seen from Table 1 above, the zirconium-titanium dioxide nanoparticles were finally prepared by the nano-titanium dioxide modification method provided in this application. They exhibited excellent stability and dispersion performance, effectively solving the technical pain point of easy agglomeration of traditional nano-titanium dioxide. They can be uniformly dispersed in solvents, laying a stable morphological foundation for subsequent material applications. In turn, they fundamentally inhibited the problems of material aging and yellowing caused by ultraviolet light-induced particle photocatalytic activity.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for modifying nano-metal oxides, characterized in that, Includes the following steps: S1: Nano-sized titanium dioxide particles were prepared using a hydrothermal method; S2: Prepare a nano-titanium dioxide particle dispersion by dispersing nano-titanium dioxide particles in a solvent; S3: Adjust the nano-titanium dioxide particle dispersion to acidic or neutral conditions, add a metal modifier dropwise to the nano-titanium dioxide particle dispersion, stir the reaction, and vacuum dry to obtain modified nano-titanium dioxide particles. The metal modifier is a zirconate coupling agent.

2. The method for modifying nano-metal oxides according to claim 1, characterized in that: The central metal atom of the zirconate coupling agent is Zr, and it contains at least one saturated or unsaturated alkoxy hydrolysis group.

3. The method for modifying nano-metal oxides according to claim 2, characterized in that: The structural formula of the zirconate coupling agent is Zr(OR1)p(R2)q, p+q=4, p>0; R1 is C 1-20 A saturated or unsaturated alkyl group, wherein R2 is C 1-20 Saturated or unsaturated alkyl groups, C 1-20 One of the alkyl-substituted phenyl groups; the C 1-20 The alkylene moiety in the substituent of the alkyl-substituted phenyl group is broken by an N atom, an O atom, an ester bond, an acyl group, a sulfonate bond, a phosphate bond, a pyrophosphate bond, a sulfonyloxy group, or a sulfonyloxy group, and the H at the R2 terminal position is either substituted by a reactive group or not substituted.

4. The method for modifying nano-metal oxides according to claim 3, characterized in that, The C 1-20 The saturated or unsaturated alkyl group is selected from C14 groups whose terminal alkyl groups are substituted with or unsubstituted with an alkenyl group. 1-6 The saturated alkyl group; the reactive group is selected from amino, hydroxy, (meth)acrylate, carboxyl, epoxy, vinyl or mercapto; p is 1 and q is 3.

5. The method for modifying nano-metal oxides according to claim 1, characterized in that, The size of the nano-titanium dioxide particles is 10–1000 nm.

6. The method for modifying nano-metal oxides according to claim 1, characterized in that, The weight ratio of the nano-titanium dioxide particles to the metal modifier is 1:(0.01~0.2).

7. The method for modifying nano-metal oxides according to claim 1, characterized in that, The hydrothermal method is as follows: a titanium source is used as a precursor, and water, an organic solvent, or a mixture of the two are used as the reaction medium. The mixture is stirred evenly to obtain a precursor solution. After adjusting the pH with an acidic solution, the solution is placed in a polytetrafluoroethylene high-pressure reactor and reacted at 120–240°C for 18–24 hours. The precipitate obtained after centrifuging the suspension is washed with water, dried, and ground to obtain crystalline nano-titanium dioxide.

8. The method for modifying nano-metal oxides according to claim 7, characterized in that... : The titanium source is selected from one or more of titanium esters, titanium tetrachloride, and titanium sulfate; The organic solvent is selected from any one or more combinations of ethanol, chloroform, ethyl acetate, isopropanol, ethylene glycol, cyclohexane, and acetone; The solvent in the nano-titanium dioxide particle dispersion is selected from any one or more combinations of ethanol, chloroform, ethyl acetate, isopropanol, ethylene glycol, cyclohexane, and acetone; the mass fraction of titanium dioxide in the nano-titanium dioxide particle dispersion is 15%-40%.

9. A modified nano-titanium dioxide particle prepared by the method according to any one of claims 1 to 8.

10. An application of the modified nano-titanium dioxide particles according to claim 9, characterized in that, Used to prepare ink materials or adhesives for display devices.

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