CN118717541A

CN118717541A - A method for preparing polysiloxane-coated titanium dioxide organic microspheres

Info

Publication number: CN118717541A
Application number: CN202410648035.XA
Authority: CN
Inventors: 张婉萍; 关馨; 张倩洁
Original assignee: Shanghai Institute of Technology
Current assignee: Shanghai Institute of Technology
Priority date: 2024-05-23
Filing date: 2024-05-23
Publication date: 2024-10-01

Abstract

The present invention describes a method for preparing polysiloxane-coated titanium dioxide organic microspheres, comprising the following steps: using a uniformly dispersed titanium dioxide aqueous dispersion as component A, and a stirred mixed solution of an organic siloxane monomer and an organic solvent as component B, mixing components A and B, adding initiator 1 to react for a certain time, adding initiator 2 to react for a certain time to obtain a mixed solution, centrifugally washing and drying, and finally obtaining polysiloxane-coated titanium dioxide organic microspheres. The present invention uses polysiloxane to coat titanium dioxide, has high reaction efficiency, low energy consumption, low cost, and is convenient for laboratory operation. The prepared organic microspheres have good compatibility and dispersibility with organic matter, and because the coating of polysiloxane reduces the roughness of titanium dioxide when it is applied, the application range of titanium dioxide is expanded.

Description

Preparation method of polysiloxane coated titanium dioxide organic microspheres

Technical Field

The invention belongs to the technical field of cosmetics, and particularly relates to a preparation method of polysiloxane coated titanium dioxide organic microspheres.

Background

Nano titanium dioxide (TiO ₂) is a multifunctional component widely applied in the field of cosmetics, and can provide multiple functions of sun protection, modification, protection and the like for products. Firstly, by reflecting and scattering ultraviolet radiation, plays a key role in sun protection products to provide protection for the skin; secondly, titanium dioxide is also common in make-up products such as foundations, foundation pads and concealers, which smooth the skin and adjust the skin tone, due to its good hiding and ability to adjust the skin tone; thirdly, the white pigment can be used as a white pigment for eye shadow, blush, lipstick and other makeup products to increase the transparency and brightness of the color; in addition, it can improve the texture of cosmetics, provide a smooth feel, and enhance the durability of color in products such as eyeliner, eyebrow powder, etc.

On the one hand, the Ti-O bond in the TiO ₂ has larger polarity, the imbalance of the Ti-O bond makes the polarity of the TiO ₂ molecule very strong, the strong polarity of the molecule makes the surface of the TiO ₂ easily adsorb water molecules, the polarization of the water molecules easily form surface hydroxyl groups, the hydrophilicity is strong, the water easily aggregates, the water is difficult to disperse in an organic system, and especially in emulsion products containing higher oil content, the direct addition of the uncoated titanium dioxide can lead to oil-water separation, thereby affecting the texture and stability of the products; on the other hand, the stronger ionic arrangement and binding force in the titanium dioxide crystal structure makes the feel rough, which reduces the user's desire for some cosmetics to have smooth skin feel; these problems limit the scope of application of titanium dioxide and therefore require organic coating of titanium dioxide.

The existing organic coating method mainly comprises three steps of surfactant coating, coupling agent coating and polymer coating, and compared with other coating methods, the surfactant coating method comprises physical adsorption, wherein the physical adsorption is not firmly combined with titanium dioxide compared with chemical adsorption, and excessive surfactant residues can raise the viscosity of a product; method of polymer coating may introduce additional costs and in some cases may have an impact on the feel and texture of the product; the method of coating the coupling agent is chemical adsorption, and compared with physical adsorption, the coupling agent is more firmly combined with titanium dioxide and has strong stability; compared with the coating of an organic surface by using a polymer, the coating of the coupling agent has low cost and contributes to expanding the application range. In the case of the coupling agent coating method, however, the main (1) is to prepare nanoparticles by reacting in a solution; (2) High temperature reaction with organosilanes, and (3) use of a plasma process. The method (2) and (3) are complex, consume energy, have long synthesis time and high requirements on equipment, are inconvenient to operate in a laboratory, and the method (1) is quite simple and saves time.

Patent application number 200510023531.3 discloses a super-hydrophobic titanium dioxide film and a preparation method thereof, and specifically comprises the following steps: firstly, preparing a porous dioxide nano structure, taking dilute solution of hydrofluoric acid as electrolyte, taking an anodized sheet as a template, and performing hydrothermal treatment for 3-72 h; then soaking the porous titanium dioxide film in a methanol solution containing 1-4wt% of long-chain carboxylic acid, long-chain siloxane or long-chain perfluoro siloxane for 10-15 hours, washing by ethanol, and performing surface self-assembly after heat treatment for 2-6 hours. The method can reduce the adsorption of the monomer to the titanium dioxide by introducing hydrofluoric acid during the preparation of the porous nano structure, has the addition of volatile acid during the process, and has higher requirements on laboratory or production environment.

Patent application number 201911175729.1 discloses a titanium dioxide/fluorosilicone super-hydrophobic healable coating and a preparation method thereof, and the method specifically comprises the following steps: firstly, uniformly dispersing stearic acid and nano titanium dioxide powder in a mixed solvent of absolute ethyl alcohol and deionized water, and preserving heat for 2-5 hours at 100-120 ℃ to obtain modified nano titanium dioxide powder; simultaneously adding heptadecafluorodecyl trimethoxy silane, deionized water and ammonia water into absolute ethyl alcohol to obtain blue-white transparent sol; dispersing the modified nano titanium dioxide powder in a mixed solution of ethanol and water, and mixing with blue-white transparent sol to obtain white sol; brushing the white sol on the surface of the sample, standing at room temperature for a period of time, and then preserving the temperature at 100-120 ℃ to obtain the super-hydrophobic healable coating. The reaction process needs to be subjected to heat preservation and temperature rise for many times, so that the process is more complicated while the energy consumption is high.

Patent application number 201080009132.0 discloses a preparation method of titanium dioxide composite powder and cosmetic composition containing the composite powder, which specifically comprises the following steps: after TiO ₂ is dried at 105 ℃ for at least 4 hours, putting the mixture into a Hensel stirrer to be stirred and mixed with silicone elastomer at high speed, spraying polymethylsilsesquioxane on the mixture, mixing and dispersing, and drying at 120-150 ℃ for at least 4 hours. The reaction process is carried out at high temperature, so that the crystal lattice can be adjusted, and the optical performance of the titanium dioxide is further affected; in the coating process, the difficulty and cost of the production process are increased through a plurality of steps such as drying, spraying, stirring and mixing, re-drying and the like.

Disclosure of Invention

This section is intended to outline some aspects of embodiments of the application and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section as well as in the description of the application and in the title of the application, which may not be used to limit the scope of the application.

The present invention has been made in view of the above and/or problems occurring in the prior art.

Therefore, the invention aims to overcome the defects in the prior art and provide a preparation method of polysiloxane coated titanium dioxide organic microspheres.

In order to solve the technical problems, the invention provides the following technical scheme: a preparation method of polysiloxane coated titanium dioxide organic microspheres is characterized by comprising the following steps: comprising the steps of (a) a step of,

Mixing and dispersing titanium dioxide, a dispersing agent and water uniformly to obtain a component A;

Uniformly mixing an organic siloxane monomer and an organic solvent to obtain a component B;

under the action of mechanical force, adding an initiator 1 after mixing components A, B to obtain silanol-TiO ₂ prepolymer, and then adding an initiator 2 to obtain a mixed solution;

And centrifuging, washing, drying and crushing the mixed solution to obtain the polysiloxane coated titanium dioxide organic microspheres.

As a preferred embodiment of the preparation process according to the invention, there is provided: the dispersing agent is at least one of anionic surfactants such as sodium hexametaphosphate, sodium silicate, sodium chloride, ammonium chloride, trisodium citrate, polyethylene glycol, polymethacrylic acid, hydroxypropyl methylcellulose, polyvinylpyrrolidone, sodium polyacrylate, ethanol, sodium hydroxide, cationic cellulose, sodium dodecyl benzene sulfonate, sodium dodecyl sulfate, fatty alcohol polyoxyethylene ether carboxylate, fatty acid salt, acyl sarcosinate, acyl glutamate, succinate sulfonate, fatty alcohol polyoxyethylene ether sulfate, monoalkyl phosphate and the like, cetyl trimethyl quaternary ammonium salt, cetyl trimethyl ammonium chloride, stearyl trimethyl ammonium chloride, behenyl trimethyl ammonium chloride, stearamide dimethyl ammonium chloride, dioctadecyl dimethyl ammonium chloride, trioctadecyl methyl ammonium chloride and the like, sodium isobutyl sulfonate, di-stearic acid polyethylenglycol ether and a composite polymer polyelectrolyte dispersing agent.

As a preferred embodiment of the preparation process according to the invention, there is provided: the dispersing mode is at least one of ultrasonic, stirring and ball milling.

As a preferred embodiment of the preparation process according to the invention, there is provided: the organosiloxane monomer is at least one of 3-aminopropyl trimethoxysilane APTMS, 3-isocyanatopropyl trimethoxysilane IPTMS, aminopropyl trimethoxysilane APS, 3-aminopropyl triethoxysilane APTES, N-propyl triethoxysilane PTES, 3-methacryloxypropyl trimethoxysilane MPS, N-2- (aminoethyl) -3-aminopropyl trimethoxysilane, 3-glycidyltrimethoxysilane GLYMO, N-ethoxysilane TEOS, methyltriethoxysilane MTES, gamma-propyloxypropyl trimethoxysilane, 3- (trimethoxysilyl) propyl methacrylate TMSPM, alpha-aminopropyl triethoxysilane KH 550, gamma-glycidoxypropyl trimethoxysilane KH560 and 3-trimethoxysilyl propyl methacrylate KH 570.

As a preferred embodiment of the preparation process according to the invention, there is provided: the organic solvent is at least one of ethanol, acetone, ethylene glycol, propylene glycol, butanol, toluene, xylene, o-xylene and methanol.

As a preferred embodiment of the preparation process according to the invention, there is provided: the initiator 1 is at least one of hydrochloric acid, sulfuric acid, citric acid and hydrofluoric acid.

As a preferred embodiment of the preparation process according to the invention, there is provided: the initiator 2 is at least one of triethylamine, maleic anhydride MA, ammonia water, sodium hydroxide and potassium hydroxide.

As a preferred embodiment of the preparation process according to the invention, there is provided: the mechanical force is at least one of ball milling, air milling, sand milling, high pressure and stirring under the action of mechanical force.

As a preferred embodiment of the preparation process according to the invention, there is provided: the mass ratio of the organosilicon monomer to the titanium dioxide is 10:1-1:1.

It is a further object of the present invention to overcome the deficiencies of the prior art and to provide an application of polysiloxane coated titanium dioxide organic microspheres.

The invention has the beneficial effects that:

(1) The synthesis method provided by the invention has the advantages of high synthesis efficiency, low cost, low equipment requirement and convenience in laboratory operation.

(2) The product prepared by the invention improves the dispersion degree of titanium dioxide in an organic system on one hand; on the other hand, the touch of the titanium dioxide itself is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. Wherein:

FIG. 1 is a schematic illustration of polysiloxane/titanium dioxide composite formation.

Fig. 2a and 2b are SEM pictures of the control group according to the present invention, and fig. 2c and 2d are SEM pictures of example 5.

In fig. 3, the black line shows the particle size distribution of the control group according to the present invention, and the red line shows the thermogravimetric distribution of example 5 according to the present invention.

FIG. 4 is an EDS spectrum of example 5 of the present invention.

In fig. 5, the black line represents the thermogravimetric curve of the control group according to the present invention, and the red line represents the thermogravimetric curve of example 5 according to the present invention.

Detailed Description

In order that the above-recited objects, features and advantages of the present invention will become more apparent, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways other than those described herein, and persons skilled in the art will readily appreciate that the present invention is not limited to the specific embodiments disclosed below.

Further, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic can be included in at least one implementation of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

The materials used in the embodiment of the invention are as follows: titanium dioxide (particle size 25nm, w > 99.8%, shanghai Ala Biotechnology Co., ltd.), sodium metasilicate nonahydrate (analytical grade, shanghai Ala Biotechnology Co., ltd.); methyltrimethoxysilane (MTMS for short, analytically pure, south kyo spectrum limited); hydrochloric acid (36-38 wt%, analytically pure, shanghai Taitan technologies Co., ltd.); ammonia (25-28 wt%, analytically pure, shanghai taitan technologies Co., ltd.); absolute ethanol (analytically pure, shanghai tetan technologies Co., ltd.).

The apparatus used in the embodiment of the invention comprises: electronic balance (PL 602-L, metrele Tolyduo instruments Shanghai Co., ltd.); numerical control ultrasonic cleaner (KQ-300 DA, kunshan ultrasonic instruments Co., ltd.); centrifuge (TGL-16M, hunan Instrument laboratory instruments Co., ltd.); magnetic stirrer (524G, shanghai Mei Yingpu instruments, inc.); electrothermal constant temperature blast drying oven (DHG-9146A, shanghai macro laboratory equipment Co., ltd.); laboratory syringe pumps (TYD 02, baoding Lei Fu fluid technologies limited); planetary ball mill (TJX-450, eastern Tianjing technology development Co., ltd.) particle size instrument (BROOKHAVEN, bruce sea instruments, U.S.A.; china).

The method for determining the oleophilic degree in the embodiment of the invention comprises the following steps: the sample was subjected to a lipophilicity test using a methanol titration method, the sample was dispersed in water, the powder was less polar, floating on the water, and the volume of methanol was recorded when the powder floating on the water was completely wetted. LD (%) =v/(v+10) ×100 (where LD is the degree of lipophilicity (%), V is the volume of methanol added (mL).

Example 1

The polysiloxane coated titanium dioxide organic microsphere comprises four stages of pre-dispersing titanium dioxide, pre-hydrolyzing an organic silicon monomer, forming a silanol-TiO ₂ prepolymer and forming the polysiloxane/titanium dioxide organic microsphere.

In this example, the polysiloxane coated titanium dioxide organic microsphere has a titanium dioxide mass percent of 2% and a silicon monomer mass percent of 0.647%.

In this embodiment, the crystal form of the nano titanium dioxide is rutile type.

The preparation method of the polysiloxane coated titanium dioxide organic microsphere in the embodiment comprises the following steps:

(1) 2g of nano-titania, 0.5g of 50g/L sodium silicate solution and water were sonicated at 300W power for 30min.

(2) 0.647G of methyltrimethoxysiloxane was magnetically stirred with absolute ethanol at a rate of 500rpm for 30min at 40.+ -. 2 ℃.

(3) After mixing (1) and (2), 0.3g of 0.5wt% hydrochloric acid was added, and ball-milling was performed at a rate of 370rpm for 4 hours.

(4) To (3), 1.2g of 5wt% aqueous ammonia was added, and the mixture was ball-milled at a rate of 370rpm for 1 hour.

(5) The reaction solution of (4) was centrifuged at 8000rpm for 10min, followed by washing with water 1 time and with absolute ethanol 2 times, and then dried at 70℃for 12 hours, and ground into powder in a mortar to obtain polysiloxane/titania organic microspheres.

Example 2

This embodiment differs from embodiment 1 in that: the methyltrimethoxysiloxane in example 1 was adjusted to 1.294g, and the organic microspheres were produced under the same conditions as in example 1.

Example 3

This embodiment differs from embodiment 1 in that: the methyltrimethoxysiloxane in example 1 was adjusted to 2.588g, and the organic microspheres were produced under the same conditions as in example 1.

Example 4

This embodiment differs from embodiment 1 in that: the methyltrimethoxysiloxane in example 1 was adjusted to 5.176g, and the organic microspheres were produced under the same conditions as in example 1.

Example 5

This embodiment differs from embodiment 1 in that: the methyltrimethoxysiloxane in example 1 was adjusted to 10.352g, and the organic microspheres were produced under the same conditions as in example 1.

Example 6

This embodiment differs from embodiment 1 in that: the methyltrimethoxysiloxane in example 1 was adjusted to 15.528g, and the organic microspheres were produced under the same conditions as in example 1.

Table 1 shows the lipophilicity values of examples 1 to 6 in the present invention.

TABLE 1

As is clear from Table 1, the degree of lipophilicity gradually increased with increasing the amount of the silane coupling agent, and the degree of lipophilicity slightly decreased with increasing the amount of the coupling agent. The reason is that the silane coupling agent is hydrolyzed into silanol, the silanol is dehydrated and condensed into an oligomer, si-OH in the oligomer forms a hydrogen bond with-OH on the surface of TiO ₂, and the silane coupling agent is dehydrated to form siloxane bonds and form monomolecular film adsorption; as the usage amount of the silane coupling agent increases, the adsorption amount increases, and the oleophilic degree increases; however, when the dosage of the silane coupling agent is too large, the siloxane anions generated by hydrolysis can generate a bridging effect with Si atoms in the silane coupling agent molecules bonded on the TiO ₂ on the surface of the TiO ₂, so that flocculation of TiO ₂ powder is caused, and the lipophilicity of the TiO ₂ is reduced.

Example 7

In example 5, the time for adding 0.5wt% hydrochloric acid was adjusted to 1h, 2h, 3h, 4h, and 5h, respectively. The values of the lipophilicity are shown in Table 2 below:

TABLE 2

As seen from table 2, the overall rule is that the lipophilicity increases and then decreases. This is probably because, in the initial stage, the degree of hydrolysis reaction is more complete with the lapse of time, thereby directly affecting the possibility and degree of the subsequent polycondensation reaction. Since more hydroxyl groups provide more opportunities for the formation of silicon oxygen bonds (Si-O-Si), but hydrolysis of the silicon monomer to silanol favors chemical bonding with hydroxyl groups on the titanium dioxide surface, the lipophilicity reaches a maximum at 4h of reaction, because-OH on the TiO2 surface is reduced, thereby increasing lipophilicity. However, if the time is too long, further reactions may be initiated. On the one hand, too long hydrolysis times may result in supersaturation of silanol groups on the surface of the inorganic particles, and these hydroxyl groups may cause aggregation between the inorganic particles through hydrogen bonding or other weak interactions, thereby reducing the effective coating rate. On the other hand, as the hydrolysis proceeds, the silanol groups formed undergo further polycondensation to form silicon-oxygen bonds (Si-O-Si). If the hydrolysis time is too long, the polycondensation reaction may occur spontaneously on the surface of the inorganic particles or between the particles, resulting in bridging between the inorganic particles or formation of a silica network, and non-uniformly coating the organic matrix.

Example 8

In example 5, the time for adding 5wt% ammonia water was adjusted to 0.5h, 2h, 3h, 4h, and 5h, respectively. The lipophilicity values are determined as shown in Table 3 below:

TABLE 3 Table 3

As seen from table 3, the overall rule is that the lipophilicity increases and then decreases. In the initial stage, the polycondensation reaction becomes more sufficient with the lapse of time. When the polycondensation time reaches 1 hour, the lipophilicity reaches the highest, and the wrapping effect is also the best. However, over time, the lipophilicity begins to decrease. The reasons for this phenomenon may be manifold. On the one hand, as the polycondensation reaction time is prolonged, large particle agglomeration or aggregation phenomenon may be formed. Too long a polycondensation reaction time can result in further condensation of silanol groups to form a larger network of siloxane bonds, thereby causing agglomeration or aggregation between inorganic particles. These large particle aggregates may reduce the dispersibility of the particles, making the organic matrix ineffective for coating the particles, resulting in a decrease in coating rate. On the other hand, the polycondensation reaction for a long time may cause a change in the structure of the coating layer, so that the coating layer becomes unstable or fragile, and is liable to be broken or detached. This exposes more of the surface of the inorganic particles, reducing the coating of the particles with the organic matrix and thus reducing the coating rate.

Example 9

The ball milling rates in the steps (3) and (4) in example 5 were adjusted to 170rpm, 370rpm, 570rpm, 770rpm and 970rpm, respectively. The lipophilicity values are shown in Table 4 below:

TABLE 4 Table 4

As seen from table 4, the overall rule is that the lipophilicity increases and then decreases. With the increase of the ball milling rate, the collision frequency and collision energy among particles are improved, so that the adsorption and coating of the surfaces of the particles and an organic matrix are promoted, the oleophilic degree is finally increased along with the increase of the ball milling rate, and the oleophilic degree (LD) can reach the maximum value of 57.8% when the ball milling rate is 370 rpm. However, as the ball milling rate continues to increase, the lipophilicity decreases. This may be due to damage to the coating caused by excessive crushing. With further increase of ball milling rate, excessive collision and breakage between particles may occur, and the coating layer on the surfaces of the particles may be damaged. When the coating layer is severely damaged, the particle surface is exposed, and the organic matrix cannot effectively coat the particles, resulting in a decrease in lipophilicity. In addition, under high-speed ball milling conditions, the coating layer on the particle surface may be reassembled and recombined to form a new coating layer structure. This may cause the original coating layer to be reassembled, losing the original coating effect, and thus reducing the coating effect.

Example 10

The percentages of hydrochloric acid added in example 5 were adjusted to 0.1%, 0.2%, 0.3%, 0.7%, 1.0% and 1.3%, respectively. The values of the lipophilicity are shown in Table 5 below:

TABLE 5

As seen in table 5, the overall rule is that the lipophilicity increases and then decreases. The reason may be that the acid content affects the coating rate mainly by affecting the hydrolysis rate of the silicon monomer. It is widely accepted that hydrolysis is caused by nucleophilic attack of silicon atoms by oxygen in water. Under acidic conditions, alkoxide groups are first protonated, reducing the electron density in the silicon, making it more electrophilic and therefore more vulnerable to water, thereby facilitating the hydrolysis process of the silicon monomer. The degree of Lipophilicity (LD) reaches a maximum of 66.7% at a percentage of 0.656%. As the percentage of acid increases in the initial stage, the silanol of the silicon monomer hydrolysis increases, thereby increasing the contact site with titanium dioxide, resulting in an increase in lipophilicity until a maximum value is reached. Then as the percentage of acid continues to increase, the pH of the system decreases, gradually approaching the isoelectric point of TiO ₂ (pH. Apprxeq. 3.6). At this time, the microscopic force is expressed as coulomb repulsion > > van der waals force, so that the system becomes unstable, and the TiO ₂ is more likely to agglomerate, thereby causing the reduction of the lipophilicity.

Example 11

The percentage of ammonia water was adjusted to 0.6%, 1.2%, 2.4%, 3.6% and 4.8% on the premise of adding 0.7% of hydrochloric acid in example 10. The respective lipophilicity values are shown in Table 6 below:

TABLE 6

As seen from table 6, the overall rule is that the lipophilicity increases and then decreases. The reason may be that the hydroxyl anions of ammonia (OH ^-) and deprotonated silanol (Si-O) are more suitable nucleophiles than water and silanol, so they attack the silicon atom. Under such conditions, the hydrolysis and condensation reactions occur simultaneously. However, the rate of condensation is higher than the rate of hydrolysis, resulting in accelerated formation of branched oligomers, polymers or oxygen bridged macromolecular networks. Thus, in the initial stage, as the content of the base increases, the amount of silanol condensed into polysiloxane may increase, thereby increasing the amount of coated titanium dioxide and improving the lipophilicity. When the percentage of the alkali is 1.2%, the Lipophilicity (LD) reaches a maximum value of 66.7%. However, as the alkali content continues to increase, it may cause hydrolysis to generate siloxane anions, which are combined with Si atoms in the silane coupling agent molecules on the surface of TiO ₂, thereby causing flocculation of TiO ₂ powder and reducing the lipophilicity of TiO ₂.

It can be seen that the present invention provides a sample with polysiloxane coated surface that has enhanced dispersibility relative to the uncoated powdered TiO ₂, and is more compatible with organic media. The experimental materials used are low in pollution, low in energy consumption and short in time, and a synthesis mode convenient for laboratory preparation and industrialization is provided.

It should be noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present invention may be modified or substituted without departing from the spirit and scope of the technical solution of the present invention, and it should be covered in the scope of the present invention.

Claims

1. A method for preparing polysiloxane-coated titanium dioxide organic microspheres, characterized in that: comprising:

Mix titanium dioxide, a dispersant and water and disperse them uniformly to obtain component A;

The organosiloxane monomer and the organic solvent are uniformly mixed to obtain component B;

Under the action of mechanical force, components A and B are mixed and then initiator 1 is added to obtain silanol-TiO ₂ prepolymer, and then initiator 2 is added to obtain a mixed solution;

The mixed solution is centrifuged, washed, dried and crushed to obtain polysiloxane-coated titanium dioxide organic microspheres.

2. The preparation method according to claim 1, characterized in that: the dispersant is at least one of anionic surfactants such as sodium hexametaphosphate, sodium silicate, sodium chloride, ammonium chloride, trisodium citrate, polyethylene glycol, polymethacrylic acid, hydroxypropyl methylcellulose, polyvinyl pyrrolidone, polyacrylic acid sodium salt, ethanol, sodium hydroxide, cationic cellulose, sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, fatty alcohol polyoxyethylene ether carboxylates, fatty acid salts, acyl sarcosinates, acyl glutamates, succinate sulfonates, fatty alcohol polyoxyethylene ether sulfates, monoalkyl phosphates, hexadecyl trimethyl quaternary ammonium salts, hexadecyl trimethyl ammonium chloride, octadecyl trimethyl ammonium chloride, behenyl trimethyl ammonium chloride, stearamide dimethyl ammonium chloride, dioctadecyl dimethyl ammonium chloride, tri-hexadecyl methyl ammonium chloride, sodium isobutyl sulfonate, distearic acid polyethanol ether, and composite polymer polyelectrolyte dispersants.

3. The preparation method according to claim 1, characterized in that: the dispersion method is at least one of ultrasound, stirring, and ball milling.

4. The preparation method according to claim 1, characterized in that: the organosiloxane monomer is at least one of 3-aminopropyltrimethoxysilane APTMS, 3-isocyanatepropyltrimethoxysilane IPTMS, aminopropyltrimethoxysilane APS, 3-aminopropyltriethoxysilane APTES, n-propyltriethoxysilane PTES, 3-methacryloxypropyltrimethoxysilane MPS, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-trimethoxytrimethoxysilane GLYMO, n-ethoxysilane TEOS, methyltriethoxysilane MTES, γ-methacrylatepropyloxypropyltrimethoxysilane, 3-(trimethoxysilyl)propylmethacrylate TMSPM, α-aminopropyltriethoxysilane KH 550, γ-glycidyloxypropyltrimethoxysilane KH560, and 3-trimethoxysilylpropylmethacrylate KH570.

5. The preparation method according to claim 1, characterized in that the organic solvent is at least one of ethanol, acetone, ethylene glycol, propylene glycol, butanol, toluene, xylene, o-xylene, and methanol.

6. The preparation method according to claim 1, characterized in that: the initiator 1 is at least one of hydrochloric acid, sulfuric acid, citric acid, and hydrofluoric acid.

7. The preparation method according to claim 1, characterized in that: the initiator 2 is at least one of triethylamine, maleic anhydride MA, ammonia water, sodium hydroxide and potassium hydroxide.

8. The preparation method according to claim 1, characterized in that: the mechanical force is at least one of ball milling, air milling, sand milling, high pressure, and stirring.

9 . The preparation method according to claim 1 , wherein the mass ratio of the organic silicon monomer to titanium dioxide is 10:1 to 1:1.

10. Use of polysiloxane-coated titanium dioxide organic microspheres prepared by the preparation method according to any one of claims 1 to 9.