WO2016026464A1

WO2016026464A1 - Organic/inorganic hybrid janus particle and preparation method and modification method, and modified janus particle and use thereof

Info

Publication number: WO2016026464A1
Application number: PCT/CN2015/087800
Authority: WO
Inventors: 杨振忠; 于啸天; 孙怡菁; 梁福鑫; 张成亮
Original assignee: 中国科学院化学研究所
Priority date: 2014-08-22
Filing date: 2015-08-21
Publication date: 2016-02-25
Also published as: CN105440218A; CN105440218B

Abstract

Disclosed are an organic/inorganic hybrid Janus particle and a preparation method and a modification method therefor, and a modified Janus particle and use thereof. The method for preparing the organic/inorganic hybrid Janus particle comprises the following steps: 1) the polymer microspheres are dispersed in water to obtain a seed emulsion; 2) a silane coupling agent emulsion is added to the seed emulsion, and then subjected to a polymerization reaction under mechanical stirring, followed by phase separation to obtain a Janus particle emulsion; the silane coupling agent emulsion comprises a silane coupling agent monomer and a polymerization initiator; 3) the Janus particle emulsion obtained in step 2) is dried by a spray drying method or a freeze drying method to obtain a Janus particle having separated organic and inorganic portions.

Description

Organic/inorganic hybrid Janus granule, preparation method and modification method thereof, and modified Janus granule and application thereof

Cross-reference to related applications

The present application claims priority to Chinese Patent Application No. 201410419504.7, filed on Jan. 22,,,,,,,,,

Technical field

The invention relates to an organic/inorganic hybrid Janus particle, a preparation method and a modification method thereof, and a modified Janus particle and an application thereof, in particular to an organic/inorganic hybrid Janus particle and a controllable batch preparation method thereof, and an organic Modified method of modifying inorganic/inorganic hybrid Janus particles, and modified organic/inorganic hybrid Janus particles and their applications.

Background technique

The development of human society has always been based on materials, and new materials play a vital role in promoting social progress. The Janus material refers to a special material with a Janus structure, which is a new class of materials with special microstructure and functional properties. In recent years, due to its unique structure, dual performance and wide application prospects, Janus has become a new research hotspot in the field of materials.

Broadly speaking, as long as the asymmetry center of the particles can be called Janus particles, it can be not only a structural asymmetry, but also a structural asymmetry. Based on this special property, Janus granules provide an ideal research platform for further design of new particle emulsifiers, heterogeneous catalysts, research on nanomotors for driving nanomachines, and assembly into superstructures as building units. The fields of physics, chemistry, biology and so on have extremely broad application prospects, which play a vital role in promoting the development of new materials.

In 1991, the famous French scientist de Gennes first used the term “Janus” to describe particles with dual properties in the Nobel Prize-winning speech, and the films formed by these particles were aptly called “breathing skin” because these There is a certain gap between the particles, which can provide conditions for mass transfer and even reaction of the internal and external environment. De Gennes’s speech sparked research on Janus materials. Interestingly, the term "Janus" has been widely used to describe micelles, dendrimers, and hard particles with a Janus structure (A. Perro, S. Reculusa, S. Ravaine, EB Bourgeat-Lami, E. Duguet, Design and synthesis of Janus micro-and nanoparticles. J. Mater. Chem, 2005, 15 (35-36): 3745-3760).

The Janus material with special microstructure has become a research hotspot in the field of materials science due to the integration and unification of two different or even opposite properties on a single particle. As a solid emulsifier, Janus granules play an important role in daily life. However, the complex structure determines the particularity of its preparation method. Although various preparation methods have been reported, there are still many problems in the existing methods for preparing Janus materials. For example, the most commonly used interface protection method can achieve precise control of Janus material structure, but it is difficult to mass production. The Janus material prepared by microfluidic method is strictly divided and has various shapes, but the size is large, and submicron can not be obtained. Nanoscale materials; the template process is complex and the preparation efficiency is low. In addition, the current methods for easy mass production are phase separation and interface nucleation, but the Janus material prepared by these methods is difficult to achieve strict division of chemical composition and fine control of microstructure. Therefore, there is still a serious lack of fine control methods for the strict zoning and microstructure of Janus particle composition, morphology and chemical composition. The large-scale preparation of Janus particles is still the biggest bottleneck restricting its wide application.

Transport accidents will inevitably occur in oil transportation, so the resulting crude oil leakage has become a major source of pollution in our ecological environment. The treatment of oil pollution has also become a key research topic for many scientists and environmentalists. At present, the main treatment methods for crude oil leakage are as follows: 1. Physical method, 2. Chemical method, 3. Biochemical method. Although these methods can play the role of oil-water mixture treatment, they still have the characteristics of large occupied resources, easy secondary pollution, incomplete separation, and long purification time.

In view of the above, the inventors conducted intensive studies and found that the specific modified Janus particles have a good sewage treatment effect, in particular, using Janus particles to prepare a magnetically responsive Janus particle as a particle surface. The emulsifier emulsifies the oil-water mixture, so that the obtained emulsion droplets also have magnetic responsiveness, so magnetic manipulation of the emulsion droplets can be realized by using a magnetic field, thereby realizing rapid oil-water separation, and at the same time, in the case of increasing the magnetic field effect, it can be realized The emulsion droplets are demulsified to recover magnetic Janus particles and crude oil. Accordingly, new solutions are provided for the treatment of oil pollution.

Summary of the invention

Based on the above problems in the prior art, the object of the present invention is to provide an organic/inorganic hybrid Janus particle whose structure can be precisely controlled, the ratio of the organic part and the inorganic part is adjustable, the reaction is simple, and can be mass-produced and the preparation method thereof .

Another object of the present invention is to provide a method for modifying organic/inorganic hybrid Janus particles and modified Janus particles.

It is also an object of the present invention to provide an application of modified Janus particles.

In order to achieve the above object, an embodiment of the present invention provides a method for producing an organic/inorganic hybrid Janus particle, which is an organic/inorganic hybrid Janus particle prepared by an emulsion polymerization method. The method comprises the following steps:

1) dispersing the polymer microspheres in water to obtain a seed emulsion;

2) adding a silane coupling agent emulsion to the seed emulsion, performing polymerization under mechanical stirring, and generating phase separation to obtain a Janus particle emulsion; the silane coupling agent emulsion includes a silane coupling agent monomer having a double bond and Polymerization initiator;

3) The Janus particle emulsion obtained in the step 2) is dried by a spray drying method or a freeze drying method to obtain organic and inorganic partially separated Janus particles.

In one example, in step 1), the polymer may be, for example, polystyrene, polyacrylonitrile or polyacrylate or the like. The polymer may be a linear polymer or a crosslinked polymer. When the polymer is a crosslinked polymer, one of divinylbenzene, 4-chloromethylstyrene, and ethylene glycol dimethacrylate (EGDMA) or any combination thereof may be used as the crosslinking agent. .

The polymer microspheres may be hollow spherical particles or solid spherical particles. Further, the polymer microspheres are preferably nano-scale linear polystyrene hollow spherical template particles, micron-sized linear polystyrene hollow spherical template particles, nano-sized polystyrene hollow spherical template particles, nano-scale linear polystyrene One of vinyl solid spherical template particles, micron-sized linear polystyrene solid spherical template particles or nano-sized polystyrene solid spherical template particles.

In one example, in the step 1), the seed emulsion has a solid content of 0.1% to 10% by mass, preferably 4% to 8%, more preferably 4.41% to 7.89%.

In one example, in the step 1), when the polymer microspheres are dispersed in water, To add a surfactant. The surfactant is used in an amount of 0.1 ‰ to 2 质量 by mass. As the surfactant, a surfactant used in the step 2) described later can be used.

In one example, in the step 2), the silane coupling agent emulsion is preferably an emulsion obtained by mixing a silane coupling agent monomer having a double bond, a polymerization initiator, a surfactant, and water.

Wherein the silane coupling agent monomer having a double bond has a mass percentage of 8-20%, preferably 8-17%, more preferably 8.32%-16.65%; and the mass of the polymerization initiator is 100% The content of the component is 0.1 to 10 Å, preferably 0.8 to 1.8 Å, more preferably 0.832 Å to 1.737 Å; the mass percentage of the surfactant is 0.6 to 2 Å, preferably 0.6 to 1.7 Å, more preferably 0.652‰-1.66‰; the balance is water.

The silane coupling agent monomer having a double bond may be, for example, 3-(methacryloyloxy)propyltrimethoxysilane.

The polymerization initiator may be, for example, one of potassium persulfate, ammonium persulfate, and azobisisobutylphosphonium hydrochloride (AIBA), or any combination thereof.

The surfactant may be, for example, one of a cationic surfactant, an anionic surfactant, a nonionic surfactant, or any combination thereof.

The cationic surfactant may, for example, be octadecylamine hydrochloride, dioctadecylamine hydrochloride, N,N-dimethyloctadecylamine hydrochloride or dodecyltrimethylbromide. Ammonium and the like. The anionic surfactant may, for example, be sodium lauryl sulfate, sodium dodecylsulfonate or sodium dodecylbenzenesulfonate. Examples of the nonionic surfactant include, for example, Span 80, Tween 80, octylphenol ethoxylate, and dodecyl alcohol ethoxylate.

Typically, the silane coupling agent emulsion is preferably composed of the following mass percent components:

3-(methacryloyloxy)propyltrimethoxysilane 8%-17%;

Potassium persulfate 0.8‰-1.8‰;

Sodium lauryl sulfate 0.6‰-1.7‰;

The balance is water and the total mass percentage of each component is 100%.

Further, the silane coupling agent emulsion is more preferably composed of the following mass percentage components:

3-(methacryloyloxy)propyltrimethoxysilane 8.32%-16.65%;

Potassium persulfate 0.832‰-1.737‰;

Sodium lauryl sulfate 0.652 ‰-1.66 ‰;

The balance is water and the total mass percentage of each component is 100%.

In one example, in the step 2), the temperature of the polymerization reaction is 60 to 90 ° C, preferably 70 ° C; the polymerization reaction time is 6 to 30 hours, preferably 18 to 30 hours, more preferably 24 hours.

Another embodiment of the present invention also provides organic/inorganic hybrid Janus particles prepared by the above-described method for preparing organic/inorganic hybrid Janus particles.

Another embodiment of the present invention further provides a method for modifying organic/inorganic hybrid Janus particles, comprising the steps of: dispersing organic/inorganic hybrid Janus particles prepared by the above preparation method in a solvent, and adding a silane coupling The crosslinking agent is reacted at a reaction temperature of 20 ° C to 90 ° C for 4 to 24 hours, and after the completion of the reaction, washing with ethanol and water, respectively, to obtain hydrophobically modified organic/inorganic hybrid Janus particles.

In one example, the dispersion concentration of the organic/inorganic hybrid Janus particles in a solvent is from 0.1% to 40% by mass. The mass ratio of the silane coupling agent to the organic/inorganic hybrid Janus particles is from 1:100 to 1:10.

The solvent may be, for example, methanol, ethanol, toluene, n-hexane or chloroform.

The silane coupling agent may be, for example, 3-aminopropyltriethoxysilane, n-octyltrimethoxysilane, octadecyltrimethoxysilane, octadecyltrichlorosilane, or γ-glycidol. Ether oxypropyltrimethoxysilane.

One embodiment of the present invention also provides hydrophobically modified organic/inorganic hybrid Janus particles prepared by the above modification method.

Another embodiment of the present invention also provides a method for modifying organic/inorganic hybrid Janus particles, comprising the steps of dispersing the above hydrophobically modified organic/inorganic hybrid Janus particles in concentrated sulfuric acid at a sulfonation temperature. The reaction was carried out at 0 ° C to 20 ° C for 5 min to 15 min, and then washed with water and ethanol, respectively, and lyophilized to obtain an organic/inorganic hybrid Janus granule having a polystyrene end.

Wherein the mass ratio of the concentrated sulfuric acid to the hydrophobically modified organic/inorganic hybrid Janus particles is from 1:1 to 20:1.

One embodiment of the present invention also provides sulfonated organic/inorganic hybrid Janus particles prepared by the above modification method.

Another embodiment of the present invention also provides a method for modifying organic/inorganic hybrid Janus particles, which is a polymer-based organic/inorganic hybrid Janus based on a graft-to method. The method of granules comprises the steps of: dispersing the above hydrophobically modified organic/inorganic hybrid Janus particles into a solvent, adding a polymer and an initiator to be grafted onto the organic/inorganic hybrid Janus particles at a reaction temperature of 60 The reaction was carried out at a temperature of ° C to 90 ° C for 6 to 24 hours to obtain a polymer-complexed organic/inorganic hybrid Janus particle.

In one example, the solvent can be, for example, methanol or ethanol.

The polymer may, for example, be a polymer having a mercapto group at the end group, preferably PEO-SH, P4VP-SH or the like.

The initiator may be, for example, azobisisobutyronitrile or benzoyl peroxide.

The dispersion concentration of the organic/inorganic hybrid Janus particles in a solvent is from 0.1% to 10% by mass. The mass ratio of the organic/inorganic hybrid Janus particles to the polymer is from 2:1 to 1:5.

Another embodiment of the present invention also provides a method for modifying organic/inorganic hybrid Janus particles, which is a method for preparing polymer composite organic/inorganic hybrid Janus particles based on a graft-from method. Including the following steps:

a) dispersing the above sulfonated organic/inorganic hybrid Janus particles in a solvent, adding an amino group-containing initiator azodiisobutylphosphonium hydrochloride, and reacting at a reaction temperature of 25 ° C to 50 ° C. 48 hours, obtaining organic/inorganic hybrid Janus particles terminated with polystyrene;

b) Then, the above Janus particles are dispersed in a solvent, polymer monomers are added, and polymerization is carried out at a polymerization temperature of 60 ° C to 90 ° C for 8 to 24 hours to obtain a polymer composite organic material prepared by the graft-from method. /Inorganic hybrid Janus particles.

In one example, the solvent may be water, methanol or ethanol, and the like, and the above steps a) may be the same as or different from the solvent used in the step b).

The dispersion concentration of the sulfonated organic/inorganic hybrid Janus particles in water is from 0.1% to 10% by mass. The mass ratio of the initiator to the sulfonated organic/inorganic hybrid Janus particles is from 1:100 to 1:10. The polymer monomer can be, for example, acrylic acid or sodium styrene sulfonate. The mass ratio of the polymer monomer to the sulfonated organic/inorganic hybrid Janus particles is from 1:100 to 1:1.

One embodiment of the present invention also provides polymer-composited organic/inorganic hybrid Janus particles prepared by the above modification method.

Another embodiment of the present invention also provides the use of the above polymer-complexed organic/inorganic hybrid Janus particles in sewage treatment.

In one example, the application is to disperse the polymer-composited organic/inorganic hybrid Janus particles in a sewage containing a charged polymer to be treated, and the dispersion concentration is 0.1% to 1% by mass. After standing for 0.5-24 hours, Janus particles can adsorb the charged polymer in the sewage, and the separation of the charged polymer in the sewage can be achieved by centrifugation.

Another embodiment of the present invention also provides a method for modifying organic/inorganic hybrid Janus particles, comprising the steps of dispersing the above sulfonated organic/inorganic hybrid Janus particles in deionized water and adding a magnetic precursor The aqueous solution is adsorbed under nitrogen for 1-12 hours, and then 0.5 to 3 hours of ammonia gas is introduced into the system to prepare magnetic organic/inorganic hybrid Janus particles.

In one example, the dispersed concentration of the sulfonated organic/inorganic hybrid Janus particles in deionized water is from 0.01% to 1% by mass.

The magnetization precursor is a mixture of a divalent iron salt and a ferric salt in a molar ratio of 1:1 to 1:2, preferably a mixture of 1:2 molar ratio. The divalent iron salt may, for example, be ferrous sulfate heptahydrate or ferrous chloride tetrahydrate. The ferric salt may, for example, be anhydrous ferric chloride, ferric chloride hexahydrate or iron sulfate.

Typically, in the aqueous solution of the magnetic precursor, the concentration of the ferrous sulfate heptahydrate is 0.051%-5.1% by mass, and the concentration of the ferric chloride is 0.059%-5.9% by mass percentage. .

One embodiment of the present invention also provides magnetic organic/inorganic hybrid Janus particles prepared by the above modification method.

One embodiment of the present invention also provides the use of the above magnetic organic/inorganic hybrid Janus particles as a particulate emulsifier.

In one example, the application is to add magnetic organic/inorganic hybrid Janus particles to a mixture of an aqueous phase and an oil phase, and shear emulsified for 1-5 minutes at a rotational speed of 10,000 rpm to 35,000 rpm using a high speed shear emulsifier. An emulsion using Janus granules as a solid emulsifier can be obtained.

The oil phase may be an organic solvent incompatible with water, such as toluene, liquid paraffin, n-hexane, n-heptane, n-octane, n-decane, cyclohexane, and the like. The mass ratio of the oil phase to the aqueous phase is from 1:10 to 1:4. The mass ratio of the magnetic organic/inorganic hybrid Janus particles to the oil phase is from 1:10 to 1:200.

Further, the mixture of the aqueous phase and the oil phase may also be industrial wastewater.

The method for preparing organic/inorganic hybrid Janus particles provided by the invention is prepared by emulsion polymerization Prepare organic/inorganic hybrid Janus particles. In the present invention, the influence parameters of the preparation process of the organic/inorganic hybrid Janus particles are further analyzed: the optimized synthesis process is finally determined by the selection and dosage of the surfactant and the determination of the ratio of the raw materials. The morphological structure of the Janus particles was characterized by measuring the size, wall thickness and surface morphology of the particles by electron microscopy. It can be known that the structure of the Janus granular material prepared by the method of the invention can be precisely controlled, the ratio of the organic part and the inorganic part can be adjusted, the reaction is simple, and the batch can be produced. Further, the organic/inorganic hybrid Janus particles of the present invention can be used as a particulate emulsifier or the like. Furthermore, the organic/inorganic hybrid Janus particles of the present invention can be polymerized and magnetically composited by surface modification, and the influencing factors in the preparation process are adjusted and controlled, and the structure is characterized and tested using an electron microscope. The emulsification effect of magnetic organic/inorganic hybrid Janus particles as a solid emulsifier.

The beneficial technical effects achieved by the present invention are as follows:

1) The Janus granule product prepared by the method for preparing organic/inorganic hybrid Janus granules of the present invention is an organic/inorganic hybrid Janus granule having strict chemical partitioning, and is widely used.

2) Janus particles have been modified and modified in the laboratory stage, the reaction is simple and effective, and it is easy to realize multi-functionality.

3) High solid content in the preparation reaction, which can realize mass industrial production.

4) The Janus granules can be prepared by one-step method or two-step method, and the synthesis process is simple and has high industrial application potential.

5) The polymer compounding and magnetic recombination of the Janus particles can be achieved by modifying the surface of the organic/inorganic hybrid Janus particles.

6) The magnetic organic/inorganic hybrid Janus particles with magnetic responsiveness can be used as a surfactant to emulsify the oil-water mixture to achieve oil-water separation.

7) Polymer composite organic/inorganic hybrid Janus particles can be used to absorb residual polymer in sewage.

DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a process for producing organic/inorganic hybrid Janus particles of the present invention.

Fig. 2 is a scanning electron micrograph showing the organic/inorganic hybrid Janus particles of the present invention.

Figure 3 shows a transmission electron micrograph of the organic/inorganic hybrid Janus particles of the present invention.

Figure 4 is a graph showing the infrared spectrum of the organic/inorganic hybrid Janus particles of the present invention. Wherein a is an infrared spectrum of the organic/inorganic hybrid Janus particles of the present invention; and b is an infrared spectrum of the polystyrene (PS) hollow sphere.

Fig. 5 shows a scanning electron micrograph of the magnetic composite Janus particles of the present invention.

Fig. 6 is a transmission electron micrograph of the magnetic composite Janus particles of the present invention.

detailed description

In accordance with one embodiment of the present invention, a method of making an organic/inorganic hybrid Janus particle having a separate organic portion and an inorganic portion is provided. The organic/inorganic hybrid Janus particles have a snow-like shape and a different composition on both sides, one side being mainly inorganic, such as silica, and the other side being mainly organic, such as polystyrene ( PS), polyacrylonitrile, polyacrylate, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a process for producing organic/inorganic hybrid Janus particles of the present invention. The preparation method of the organic/inorganic hybrid Janus particles provided by the invention is to prepare organic/inorganic hybrid Janus particles by emulsion polymerization. Referring to Figure 1, the method includes the following steps:

1) Dispersing the polymer microspheres in water to obtain a seed emulsion.

2) adding a silane coupling agent emulsion to the seed emulsion, performing polymerization under mechanical stirring, and generating phase separation to obtain a Janus particle emulsion; the silane coupling agent emulsion includes a silane coupling agent monomer and a polymerization initiator .

The method for preparing the organic/inorganic hybrid Janus particles of the present invention comprises: adding a silane coupling agent monomer to the seed emulsion of the polymer microsphere by emulsion polymerization, and the silane coupling agent monomer has a swelling effect on the polymer particles, and Under the action of the polymerization initiator, free radical polymerization is carried out in the shell layer, and the reaction induces phase separation. The large amount of monomer swells the seed shell layer, which causes the viscosity of the polymer to decrease, Ostwald ripens, and as a result, the shell The small particles produced by phase separation of the silicone polymer in the layer are easily fused together to form an inorganic convex structure. At the same time, the hydrolysis and condensation reaction of the silyloxy group of the monomer plays a role of cross-linking and fixing the morphology of the inorganic part in the preparation process and catalyzing the effect of phase separation, and at the same time hydrolyzing the original organosilicon into inorganic silicon, thereby preparing The organic/inorganic hybrid Janus particles of the invention.

In one example of the present invention, the organic/inorganic hybrid Janus particles of the present invention have a silica end at one end and a polystyrene end (PS end) at the other end. Among them, the silica end can be surface-modified with a silane coupling agent to adjust the physical properties and chemical properties of the surface, and the PS end can be sulfonated to have a sulfonic acid group, and the sulfonic acid group is used. The properties can be composite metal and polymer at the polystyrene end.

The modified silica/polystyrene Janus particles based on this example have the following technical effects:

(1) The silica/polystyrene Janus particles obtained by the preparation method of the present invention have an adjustable ratio of the silica portion to the polystyrene portion, and thus the properties of the obtained Janus particles are adjustable.

(2) The silica/polystyrene Janus particles obtained by the preparation method of the present invention have uniform particle size distribution, and the two phases of silica and polystyrene are strictly partitioned.

(3) The present invention is based on phase separation and emulsion polymerization to prepare silica/polystyrene Janus particles, which can solve the defects that traditional conventional methods are difficult to batch and accurately control, and can also be modified and functionalized according to the needs of the application. .

(4) The silica/polystyrene Janus particles have simple preparation process, high raw material conversion rate, convenient operation, easy industrial production, and good application potential.

(5) Functionalization can be achieved by grafting the polymer by graft-to and graft-from methods by modifying both ends of the silica/polystyrene Janus particles.

(6) A silica/polystyrene Janus particle having magnetic responsiveness can be obtained by modifying both ends of the silica/polystyrene Janus particle.

(7) The use of silica/polystyrene Janus particles having magnetic responsiveness as a solid emulsifier can achieve applications such as oil-water separation.

The embodiments of the present invention are specifically described by way of the following specific examples, but the present invention is not limited to the following examples. Further, the percentages in the following examples are all by mass unless otherwise specified.

Example 1

2.667 g of a linear polystyrene (PS) hollow sphere emulsion having a solid content of 37.5% was added with 20 g of deionized water and mechanically stirred into a uniform seed emulsion (solid content: 4.41%).

2.0 g of oil-soluble silane coupling agent monomer (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 2.0 g of polymerization initiator (1% potassium persulfate solution (KPS)), 0.02 g of surfactant (sodium dodecyl sulfate (SDS)) and 10 g of deionized water were mixed by ultrasonication to be uniform The silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 14.2%, the content of the polymerization initiator was 1.42 Å, the content of the surfactant was 1.42 Å, and the balance was water). The above seed emulsion was heated to 70 ° C under mechanical stirring at a rotation speed of 400 rpm, and the above silane coupling agent emulsion was added to the seed emulsion at a speed of 2.5 rpm by a mechanical peristaltic pump. The entire system was polymerized at 70 ° C for 24 hours under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion.

After the start of the polymerization, 3-(methacryloyloxy)propyltrimethoxysilane has a swelling effect on the seed shell layer, and radical polymerization is carried out in the shell layer, the reaction induces phase separation, and a large amount of monomer swollen seeds After the spherical shell layer, the viscosity of the polymer is lowered, and Ostwald is matured. As a result, small particles generated by phase separation of PMPS in the shell layer are easily fused to form an inorganic convex structure. At the same time, the siloxy hydrolytic condensation reaction of the monomer plays a role in cross-linking and fixing the morphology of the inorganic part in the preparation process and catalyzing the effect of phase separation, and at the same time hydrolyzing the original organosilicon into inorganic silicon.

The silica/polystyrene Janus particle emulsion was obtained by the above reaction, and further, the emulsion was dried by a spray drying method or a freeze drying method to obtain silica/polystyrene Janus particles.

Scanning electron micrographs and transmission electron micrographs of the silica/polystyrene Janus particles prepared above are shown in Figures 2 and 3. As can be seen from Fig. 2 and Fig. 3, the silica/polystyrene Janus particles prepared above have a uniform particle size and a particle diameter of 750 nm. The results of infrared spectroscopy analysis are shown in Figure 4. In the spectrum shown in Fig. 4, the stretching vibration peak (3650-3590 cm ^-1 ) of -OH -Si-O-Si- is strengthened by the presence of Si-OH, 3-(methacryloyloxy)propene The stretching vibration peak of C=O of the trimethoxysilane (1750-1690 cm ^-1 ), the vibration peak of the benzene ring skeleton in the copolymer of DVB and St (1600-1450 cm ^-1 3 bands), Si-O-Si And the stretching vibration peaks of Si-C are clearly visible.

Example 2

Into 2.667 g of a linear polystyrene (PS) hollow sphere emulsion having a solid content of 37.5%, 10 g of deionized water was added and mechanically stirred into a uniform seed emulsion (solid content: 7.996%).

2 g of an oil-soluble silane coupling agent monomer (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 2.0 g of a polymerization initiator (1% potassium persulfate solution (KPS)), 0.02 g surfactant (sodium dodecyl sulfate (SDS)) and 10 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 14.2%, polymerization initiator) of The content is 1.42 ‰, the content of the surfactant is 1.42 ‰, and the balance is water). The above seed emulsion was heated to 70 ° C under mechanical stirring at a rotation speed of 400 rpm, and a silane coupling agent emulsion was added to the seed emulsion at a speed of 2.5 rpm using a mechanical peristaltic pump. The entire system was polymerized at 70 ° C for 24 hours under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion. Further, the emulsion was dried by a spray drying method or a freeze drying method to obtain silica/polystyrene Janus particles.

Electron microscopy of the silica/polystyrene Janus particles prepared above showed that the snow-like particles with the organic portion and the inorganic portion were separated and obtained, and the particle size was uniform, and the particle diameter was 650 nm. The results of infrared spectroscopy analysis are shown in Figure 4. In the spectrum shown in Fig. 4, the stretching vibration peak (3650-3590 cm ^-1 ) of -OH -Si-O-Si- is strengthened by the presence of Si-OH, 3-(methacryloyloxy)propene The stretching vibration peak of C=O of the trimethoxysilane (1750-1690 cm ^-1 ), the vibration peak of the benzene ring skeleton in the copolymer of DVB and St (1600-1450 cm ^-1 3 bands), Si-O-Si And the stretching vibration peaks of Si-C are clearly visible.

Example 3

50 g of deionized water was added to 13.335 g of a linear polystyrene (PS) hollow sphere emulsion having a solid content of 37.5%, and mechanically stirred into a uniform seed emulsion (solid content: 7.89%).

5.0 g of an oil-soluble silane coupling agent monomer (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 5.0 g of a polymerization initiator (1% potassium persulfate solution (KPS)), 0.028 g of surfactant (sodium dodecyl sulfate (SDS)) and 20 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 16.65%, and the polymerization reaction was initiated The content of the agent was 1.665 ‰, the content of the surfactant was 0.932 ‰, and the balance was water). The above seed emulsion was heated to 70 ° C under mechanical stirring at a rotation speed of 400 rpm, and a silane coupling agent emulsion was added to the seed emulsion at a speed of 2.5 rpm using a mechanical peristaltic pump. The entire system was polymerized at 70 ° C for 24 hours under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion. Further, the emulsion was dried by a spray drying method or a freeze drying method to obtain silica/polystyrene Janus particles.

Electron microscopy of the silica/polystyrene Janus particles prepared above showed that the snow-like particles with the organic portion and the inorganic portion were separated and obtained, and the particle size was uniform, and the particle diameter was 750 nm. The results of infrared spectroscopy analysis are shown in Figure 4. In the spectrum shown in Fig. 4, the stretching vibration peak (3650-3590 cm ^-1 ) of -OH -Si-O-Si- is strengthened by the presence of Si-OH, 3-(methacryloyloxy)propyl The stretching vibration peak of C=O of the trimethoxysilane (1750-1690 cm ^-1 ), the vibration peak of the benzene ring skeleton in the copolymer of DVB and St (1600-1450 cm ^-1 3 bands), Si-O-Si And the stretching vibration peaks of Si-C are clearly visible.

Example 4

1 g of linear polystyrene hollow spheres were dispersed in 23.6 g of deionized water, and 0.0236 g of sodium dodecyl sulfate as a surfactant was added, and mechanically stirred into a uniform seed emulsion (solid content: 4.06%).

2.0 g of a silane coupling agent monomer having a double bond (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 0.02 g of a polymerization initiator (potassium persulfate (KPS)), 0.02 g Surfactant (sodium dodecyl sulfate (SDS)) and 10 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 16.61%, polymerization initiator) The content is 1.661 ‰, the surfactant content is 1.661 ‰, and the balance is water). The above seed emulsion was heated to 70 ° C under mechanical stirring at a rotation speed of 400 rpm, and the above silane coupling agent emulsion was added to the seed emulsion at a speed of 2.5 rpm by a mechanical peristaltic pump. The entire system was polymerized at 70 ° C for 24 hours under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion.

Then, the emulsion is dried by a spray drying method or a freeze drying method to obtain silica/polystyrene Janus particles.

Example 5

0.03 g of linear polystyrene (PS) hollow spheres were dispersed in 24.97 g of deionized water, and 0.0250 g of sodium lauryl sulfate as a surfactant was added and mechanically stirred into a uniform seed emulsion (solid content of 0.12). %).

0.03 g of a silane coupling agent monomer having a double bond (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 0.0003 g of a polymerization initiator (potassium persulfate solution (KPS)), 0.00006 g surfactant (sodium dodecyl sulfate (SDS)) and 0.3 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 9.081%, initiated by polymerization) The content of the agent was 0.9081 ‰, the content of the surfactant was 1.816 ‰, and the balance was water). The above seed emulsion was heated to 70 ° C under mechanical stirring at a rotation speed of 400 rpm, and a silane coupling agent emulsion was added to the seed emulsion at a speed of 0.1 rpm using a mechanical peristaltic pump. With continuous mechanical agitation, the entire system is The polymerization was carried out at 70 ° C for 18 h to obtain a silica/polystyrene Janus particle emulsion.

Example 6

5 g of linear polystyrene (PS) hollow spheres were dispersed in 118 g of deionized water, 0.118 g of sodium lauryl sulfate as a surfactant was added, and mechanically stirred into a uniform seed emulsion (solid content: 4.06%).

5.0 g of a silane coupling agent monomer (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 0.05 g of a polymerization initiator (potassium persulfate (KPS)), and 0.028 g of a surfactant ( Sodium dodecyl sulfate (SDS) and 20 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 19.94%, and the content of the polymerization initiator was 1.994‰). The surfactant content is 1.117 ‰, and the balance is water). The seed emulsion was heated to 90 ° C under mechanical agitation at 400 rpm, and a silane coupling agent monomer emulsion was added to the seed emulsion at a speed of 5 rpm using a mechanical peristaltic pump. The entire system was polymerized at 90 ° C for 16 h under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion.

Example 7

2 g of the crosslinked polystyrene hollow spheres were dispersed in 23.6 g of deionized water, and 0.0236 g of sodium lauryl sulfate as a surfactant was added, and mechanically stirred into a uniform seed emulsion (solid content: 7.81%).

1.5 g of a silane coupling agent monomer (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 0.015 g of a polymerization initiator (potassium persulfate (KPS)), and 0.02 g of a surfactant ( Sodium dodecyl sulfate (SDS) and 10 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 13.00%, and the content of the polymerization initiator was 1.300 ‰). The content of the surfactant is 1.734 ‰, and the balance is water). The seed emulsion containing the crosslinked styrene hollow spheres was heated to 70 ° C, and the silane coupling agent emulsion was added to the seed ball emulsion containing the crosslinked styrene hollow spheres at a speed of 2.5 rpm using a mechanical peristaltic pump. The entire system was polymerized at 70 ° C for 30 h under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion.

The emulsion is dried by spray drying or freeze drying to obtain silica/polystyrene Janus particles.

Example 8

5 g of linear polystyrene solid spheres were dispersed in 118 g of deionized water, 0.118 g of sodium lauryl sulfate as a surfactant was added, and mechanically stirred into a uniform seed emulsion (solid content: 4.06%).

6.0 g of a silane coupling agent monomer (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 0.08 g of a polymerization initiator (potassium persulfate (KPS)), and 0.030 g of a surfactant ( Sodium dodecyl sulfate (SDS) and 32 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 15.74%, and the content of the polymerization initiator was 2.999‰). The surfactant content is 0.7872 ‰, and the balance is water). The seed emulsion was heated to 70 ° C, and a silane coupling agent emulsion was added to the above seed emulsion containing the linear polystyrene solid ball at a speed of 8 rpm by a mechanical peristaltic pump. The entire system was polymerized at 70 ° C for 24 h under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion.

Example 9

1 g of the crosslinked polystyrene solid spheres were dispersed in 23.6 g of deionized water, and 0.0236 g of sodium lauryl sulfate as a surfactant was added, and mechanically stirred into a uniform seed emulsion (solid content: 4.06%).

1.0 g of a silane coupling agent monomer (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 0.01 g of a polymerization initiator (potassium persulfate (KPS)), and 0.02 g of a surfactant ( Sodium dodecyl sulfate (SDS) and 10 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 9.066%, and the content of the polymerization initiator was 0.9066‰). The surfactant content is 1.813 ‰, and the balance is water). The seed emulsion containing the crosslinked polystyrene solid spheres was heated to 60 ° C, and the silane coupling agent emulsion was added to the seed emulsion containing the crosslinked polystyrene solid spheres at a speed of 2.5 rpm using a mechanical peristaltic pump. The entire system was polymerized at 60 ° C for 24 h under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion.

Then, the emulsion is dried by spray drying or freeze drying to obtain silica/polyphenylene. Ethylene Janus granules.

Example 10

2.4 g of polyacrylonitrile (PAN) hollow spheres were dispersed in 22.6 g of deionized water, and 0.0226 g of sodium lauryl sulfate as a surfactant was added, and mechanically stirred into a uniform seed emulsion (solid content: 9.6%).

1.8 g of a silane coupling agent monomer having a double bond (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 0.018 g of a polymerization initiator (potassium persulfate solution (KPS)), 0.02 g surfactant (sodium dodecyl sulfate (SDS)) and 10 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 15.2%, polymerization initiator) The content is 1.521 ‰, the surfactant content is 1.689 ‰, and the balance is water). The above seed emulsion was heated to 80 ° C under mechanical stirring at a rotation speed of 400 rpm, and a silane coupling agent emulsion was added to the seed emulsion at a speed of 2.5 rpm using a mechanical peristaltic pump. The entire system was polymerized at 80 ° C for 18 h under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion.

Then, the emulsion is dried by a spray drying method or a freeze drying method to obtain silica/polyacrylonitrile Janus particles.

Example 11

1 g of polyacrylonitrile (PAN) solid spheres were dispersed in 23.6 g of deionized water, 0.0236 g of sodium lauryl sulfate as a surfactant was added, and mechanically stirred into a uniform sub-emulsion (solid content: 4.06%).

1.0 g of a silane coupling agent monomer having a double bond (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 0.01 g of a polymerization initiator (potassium persulfate solution (KPS)), 0.02 g surfactant (sodium dodecyl sulfate (SDS)) and 10 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 9.066%, polymerization initiator) The content is 0.9066 ‰, the surfactant content is 1.813 ‰, and the balance is water). The above seed emulsion was heated to 70 ° C under mechanical stirring at a rotation speed of 400 rpm, and a silane coupling agent emulsion was added to the seed emulsion at a speed of 2.5 rpm using a mechanical peristaltic pump. The entire system was polymerized at 70 ° C for 24 h under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion.

Example 12

Disperse 1 g of polymethyl methacrylate (PMMA) hollow spheres in 23.6 g of deionized water, add 0.0236 g of sodium lauryl sulfate as a surfactant, and mechanically stir into a uniform seed emulsion (solid content: 4.06%). .

1.0 g of a silane coupling agent monomer having a double bond (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), 0.01 g of a polymerization initiator (potassium persulfate solution (KPS)), 0.02 g surfactant (sodium dodecyl sulfate (SDS)) and 10 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 9.066%, polymerization initiator) The content is 0.9066 ‰, the surfactant content is 1.813 ‰, and the balance is water). The above seed emulsion was heated to 60 ° C under mechanical stirring at a rotation speed of 400 rpm, and a silane coupling agent emulsion was added to the seed emulsion at a speed of 2.5 rpm using a mechanical peristaltic pump. The entire system was polymerized at 60 ° C for 30 h under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion.

Then, the emulsion is dried by spray drying or freeze drying to obtain silica/polymethyl methacrylate Janus particles.

Example 13

1 g of polymethyl methacrylate (PMMA) solid spheres were dispersed in 23.6 g of deionized water, 0.0236 g of sodium lauryl sulfate as a surfactant was added, and mechanically stirred into a uniform seed emulsion (solid content: 4.06%) .

1.0 g of a silane coupling agent monomer having a double bond (3-(methacryloyloxy)propyltrimethoxysilane (MPS)), a polymerization initiator (potassium persulfate solution (KPS)) 0.01 g, surface The active agent (sodium dodecyl sulfate (SDS)) 0.02 g and 10 g of deionized water were ultrasonically mixed into a uniform silane coupling agent emulsion (wherein the content of the silane coupling agent monomer was 9.066%, polymerization initiator) The content is 0.9066 ‰, the surfactant content is 1.813 ‰, and the balance is water). The above seed emulsion was heated to 70 ° C under mechanical stirring at a rotation speed of 400 rpm, and a silane coupling agent emulsion was added to the seed emulsion at a speed of 2.5 rpm using a mechanical peristaltic pump. The entire system was polymerized at 70 ° C for 24 h under continuous mechanical stirring to obtain a silica/polystyrene Janus particle emulsion.

Example 14

0.5 g of the silica/polystyrene Janus granules prepared in Example 7 were dispersed in 100 ml of n-hexane under ultrasonic conditions, 0.1 ml of octadecyltriethoxysilane was added, and modified at 60 ° C for 24 h. After the reaction is completed, it is washed with ethanol and water, washed, and then lyophilized to obtain hydrophobically modified silica/polystyrene Janus particles.

Example 15

1.0 g of the silica/polystyrene Janus granules prepared in Example 7 were dispersed in 100 ml of n-hexane under ultrasonic conditions, and 0.1 ml of octadecyltrichlorosilane was added thereto, and the mixture was modified at 20 ° C for 4 hours. After completion, it was washed with ethanol and water, washed and lyophilized to obtain hydrophobically modified silica/polystyrene Janus particles.

Example 16

0.4 g of the hydrophobically modified silica/polystyrene Janus granules prepared in Example 14 were dispersed in 4 ml of concentrated sulfuric acid under ultrasonic conditions, and stirred under ice bath conditions at 0 ° C for 10 min, respectively, and then water, After washing with ethanol, it was lyophilized to obtain silica/polystyrene Janus particles which were sulfonated at the PS end.

Example 17

0.4 g of the hydrophobically modified silica/polystyrene Janus granules prepared in Example 14 were dispersed in 2 ml of concentrated sulfuric acid under ultrasonic conditions, stirred at 20 ° C for 5 min, and then washed with ethanol and water, respectively. Dry, to obtain silica/polystyrene Janus particles which were sulfonated at the PS end.

Example 18

0.01 g of the hydrophobically modified silica/polystyrene Janus particles prepared in Example 14 were dispersed in 10 g of methanol, 0.005 g of P4VP-SH, 0.005 g of azobisisobutyronitrile was added, and reacted at 60 ° C for 24 h. They were washed with methanol and water, and then lyophilized to obtain polymer-composited silica/polystyrene Janus particles prepared by the graft-to method.

Example 19

1 g of the hydrophobically modified silica/polystyrene Janus particles prepared in Example 14 was dispersed in 10 g of methanol, and 2.5 g of P4VP-SH, 0.01 g of azobisisobutyronitrile was added, and reacted at 90 ° C for 6 h. They were washed with methanol and water, respectively, and lyophilized to obtain polymer-composited silica/polystyrene Janus particles prepared by the graft-to method.

Example 20

1 g of the PS end prepared in Example 16 was dispersed in 10 g of deionized water with sulfonated silica/polystyrene Janus particles, and 0.01 g of azobisisobutylphosphonium hydrochloride was added and reacted at 25 ° C for 48 h. After centrifugation with deionized water, 0.01 g of acrylic acid was added, and the reaction was carried out at 90 ° C for 8 hours, followed by washing with deionized water and lyophilization to obtain polymer-composited Janus particles prepared by the graft-from method.

Example 21

0.01 g of the PS end prepared in Example 16 was dispersed in 10 g of deionized water with sulfonated silica/polystyrene Janus particles, and 0.001 g of azobisisobutylphosphonium hydrochloride was added thereto to react at 50 ° C. 8h, after washing with deionized water, 0.01 g of acrylic acid was added, and reacted at 60 ° C for 24 h, then washed with deionized water and lyophilized to obtain polymer composite Janus particles prepared by the graft-from method.

Example 22

0.02 g of the PS end prepared in Example 16 was dispersed in 200 ml of deionized water with sulfonated silica/polystyrene Janus particles, and 0.0102 g of ferrous sulfate heptahydrate, 0.0119 g of anhydrous ferric chloride, was added. Adsorption was carried out for 1 h under a nitrogen atmosphere, then ammonia gas was introduced into the solution, and after 0.5 h, it was stopped and washed with deionized water to obtain magnetic silica/polystyrene Janus particles.

Example 23

2 g of the PS end prepared in Example 16 was dispersed in 200 ml of deionized water with sulfonated silica/polystyrene Janus particles, and 1.02 g of ferrous sulfate heptahydrate, 1.19 g of anhydrous ferric chloride was added, under nitrogen. Adsorption for 12 h under the atmosphere, then ammonia gas was introduced into the solution, and after 3 h, it was stopped and washed with deionized water to obtain magnetic silica/polystyrene Janus particles.

A scanning electron micrograph of the magnetic silica/polystyrene Janus particles is shown in Fig. 5, and a transmission electron microscope photograph is shown in Fig. 6.

As can be seen from FIG. 5 and FIG. 6, the polystyrene ends of the magnetic Janus particles are composited with magnetic particles having a particle diameter of about 60 nm, and the silica ends are free of magnetic particles.

Test example 1

0.02 g of the magnetic silica/polystyrene Janus granules obtained in Example 22 were taken, and poured into a mixture of 1 g of liquid paraffin and 10 g of deionized water, and shear emulsified at 12,000 rpm using a high speed shear emulsifier. At 2 min, a stable emulsion was obtained.

Under the magnetic field strength of 0.1T, the emulsion droplets laid on the liquid surface can be moved to the side of the bottle wall, and the magnetic action time can be extended to achieve emulsion breaking, thereby achieving water and oil separation.

Test example 2

Take 0.02 g of the magnetic silica/polystyrene Janus granules prepared in Example 23, put into 1 g of industrial sewage, add 10 g of deionized water, and shear emulsification at 12000 rpm for 2 min using a high speed shear emulsifier. A stable emulsion can be obtained.

Test Example 3

0.1 g of the P4VP composite silica/polystyrene Janus particles prepared in Example 18 were dispersed in 50 g of sewage containing 0.0025 g of sodium polyacrylate, allowed to stand for 2 h, centrifuged at 12,000 rpm, and then subjected to aqueous phase to detect sodium polyacrylate. The content is 0.0005 g.

It can be seen that the above P4VP composite silica/polystyrene Janus particles can be used to absorb residual polymer in sewage.

Test Example 4

0.1 g of the polyacrylic composite composite silica/polystyrene Janus particles prepared in Example 20 was dispersed in 50 g of sewage containing 0.0025 g of polyethyleneimine, allowed to stand for 2 h, centrifuged at 12,000 rpm, and then subjected to aqueous phase to detect the polymerization therein. The content of ethyleneimine was 0.0004 g.

It can be seen that the above polyacrylic acid composite silica/polystyrene Janus particles can be used to absorb residual polymer in sewage.

According to Examples 1-23 and Test Examples 1-4, the organic/inorganic hybrid Janus particles were prepared by the preparation method of the organic/inorganic hybrid Janus particles of the present invention, and the structure was precisely controlled, and the ratio of the organic portion to the inorganic portion was adjustable. The reaction is simple, the preparation reaction has high solid content, and mass industrial production can be realized. At the same time, the obtained organic/inorganic hybrid Janus particles can be compounded by various compounds, and are easy to function as particle emulsifiers in various fields, especially in the fields of sewage treatment, oil-water separation and the like.

The above description is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can also make several improvements and retouchings without departing from the principles of the present invention. The scope of protection of the invention should be considered.

Claims

A method for preparing organic/inorganic hybrid Janus particles, comprising the steps of:

1) dispersing the polymer microspheres in water to obtain a seed emulsion;

2) adding a silane coupling agent emulsion to the seed emulsion, performing polymerization under mechanical stirring, and generating phase separation to obtain a Janus particle emulsion; the silane coupling agent emulsion includes a silane coupling agent monomer having a double bond and Polymerization initiator;

3) The Janus particle emulsion obtained in the step 2) is dried by a spray drying method or a freeze drying method to obtain organic and inorganic partially separated Janus particles.
The preparation method according to claim 1, wherein in the step 1), the polymer is polystyrene, polyacrylonitrile or polyacrylate; the polymer microsphere is a hollow sphere or a solid sphere, The polymer microspheres are preferably nano-scale linear polystyrene hollow spherical template particles, micron-sized linear polystyrene hollow spherical template particles, nano-sized polystyrene hollow spherical template particles, nano-scale linear polystyrene solid spheres One of template particles, micron-sized linear polystyrene solid spherical template particles or nano-sized polystyrene solid spherical template particles.
The production method according to claim 1 or 2, wherein in the step 1), the seed emulsion has a solid content of 0.1% to 10%, preferably 4% to 8% by mass.
The production method according to any one of claims 1 to 3, wherein in the step 1), when the polymer microspheres are dispersed in water, a surfactant is added, and the surfactant is used in a mass percentage. It is counted as 0.1‰-2‰.
The preparation method according to any one of claims 1 to 4, wherein in the step 2), the silane coupling agent emulsion is a silane coupling agent monomer having a double bond, a polymerization initiator, An emulsion obtained by mixing a surfactant and water; wherein the silane coupling agent monomer having a double bond in the silane coupling agent emulsion has a mass percentage of 8-20%, preferably 8%-17%, The polymerization initiator has a mass percentage of 0.1‰-10‰, preferably 0.8‰-1.8‰, and the surfactant has a mass percentage of 0.6‰-2‰, preferably 0.6‰-1.7‰. The balance is water.
The production method according to claim 5, wherein the silane coupling agent monomer having a double bond is 3-(methacryloyloxy)propyltrimethoxysilane, and the polymerization initiator is potassium persulfate. One of ammonium persulfate and azobisisobutylphosphonium hydrochloride; the surfactant is a cation One of a surfactant, an anionic surfactant, or a nonionic surfactant, or any combination thereof.
The production method according to claim 6, wherein the silane coupling agent emulsion is composed of the following mass percentage components:

3-(methacryloyloxy)propyltrimethoxysilane 8%-17%;

Potassium persulfate 0.8‰-1.8‰;

Sodium lauryl sulfate 0.6‰-1.7‰;

The balance is water and the total mass percentage of each component is 100%.
The preparation method according to any one of claims 1 to 7, wherein in the step 2), the temperature of the polymerization reaction is 60 to 90 ° C, preferably 70 ° C; and the polymerization reaction time is 16 to 30 hours. It is preferably 18-30 hours, more preferably 24 hours.
Organic/inorganic hybrid Janus particles prepared by the preparation method according to any one of claims 1-8.
A method for modifying organic/inorganic hybrid Janus particles, comprising the steps of: dispersing the organic/inorganic hybrid Janus particles according to claim 9 in a solvent, and adding a silane coupling agent at a reaction temperature of 20 ° C - 90 The reaction was carried out for 4 to 24 hours under the conditions of ° C, and washed with ethanol and water, respectively, to obtain hydrophobically modified organic/inorganic hybrid Janus particles.
The modification method according to claim 10, wherein the organic/inorganic hybrid Janus particles have a dispersion concentration in a solvent of from 0.1% to 40%; and the solvent is methanol, ethanol, toluene, n-hexane or trichloro Methane; the silane coupling agent is 3-aminopropyltriethoxysilane, n-octyltrimethoxysilane, octadecyltrimethoxysilane, octadecyltrichlorosilane, or γ-glycidol Ether oxypropyltrimethoxysilane; the mass ratio of the silane coupling agent to the organic/inorganic hybrid Janus particles is from 1:100 to 1:10.
Hydrophobically modified organic/inorganic hybrid Janus particles prepared by the modification method of claim 10 or 11.
A method for modifying organic/inorganic hybrid Janus particles, comprising the steps of: dispersing the hydrophobically modified organic/inorganic hybrid Janus particles according to claim 12 in concentrated sulfuric acid at a sulfonation temperature of 0 ° C-20 The reaction is carried out for 5 min to 15 min under the conditions of ° C, and then washed with water and ethanol, respectively, and lyophilized to obtain an organic/inorganic hybrid Janus granule having a polystyrene end sulfonated;

The mass ratio of the concentrated sulfuric acid to the hydrophobically modified organic/inorganic hybrid Janus particles is from 1:1 to 20:1.
A sulfonated organic/inorganic hybrid Janus particle prepared by the modification method of claim 13.
A method for modifying organic/inorganic hybrid Janus particles, which is a method for preparing polymer-composited organic/inorganic hybrid Janus particles based on a graft-to method, comprising the steps of: hydrophobically modifying according to claim 12 The organic/inorganic hybrid Janus particles are dispersed in a solvent, and the polymer and the initiator to be grafted onto the organic/inorganic hybrid Janus particles are added, and the reaction is carried out at a reaction temperature of 60 ° C to 90 ° C for 6 to 24 hours. Thus, a polymer-complexed organic/inorganic hybrid Janus particle is obtained.
The modification method according to claim 15, wherein the solvent is methanol or ethanol, and the polymer is a polymer having a mercapto group at a terminal group; and the dispersion concentration of the organic/inorganic hybrid Janus particles in a solvent is The mass percentage is from 0.1% to 10%, the mass ratio of the organic/inorganic hybrid Janus particles to the polymer is from 2:1 to 1:5, and the initiator is azobisisobutyronitrile or peroxidation. Benzoyl.
A method for modifying organic/inorganic hybrid Janus particles, which is a method for preparing polymer composite organic/inorganic hybrid Janus particles based on the graft-from method, comprising the following steps:

The sulfonated organic/inorganic hybrid Janus particles according to claim 14 are dispersed in a solvent, and an amino group-containing initiator azobisisobutylphosphonium hydrochloride is added at a reaction temperature of 25 ° C to 50 ° C. The reaction is carried out for 8-48 hours to obtain organic/inorganic hybrid Janus particles having polystyrene terminated with an azo initiator;

Then, the above Janus particles are dispersed in a solvent, polymer monomers are added, and polymerization is carried out at a polymerization temperature of 60 ° C to 90 ° C for 8 to 24 hours to obtain a polymer composite organic/inorganic compound prepared by the graft-from method. Hybrid Janus particles.
The modification method according to claim 17, wherein the solvent is water, methanol or ethanol, and the dispersion concentration of the sulfonated organic/inorganic hybrid Janus particles in water is 0.1% to 10% by mass%. The mass ratio of the initiator to the sulfonated organic/inorganic hybrid Janus particles is from 1:100 to 1:10, and the polymer monomer is sodium acrylate or sodium styrene sulfonate, and the polymer monomer is The mass ratio of the sulfonated organic/inorganic hybrid Janus particles is from 1:100 to 1:1.
Polymer composite prepared by the modification method according to any one of claims 15-18 Organic/inorganic hybrid Janus particles.
Use of the polymer composite organic/inorganic hybrid Janus particles of claim 19 in sewage treatment.
A method for modifying organic/inorganic hybrid Janus particles, comprising the steps of: dispersing the sulfonated organic/inorganic hybrid Janus particles according to claim 14 in deionized water, adding an aqueous solution of the magnetic precursor, in nitrogen The adsorption is carried out for 1 to 12 hours, and then 0.5 to 3 hours of ammonia gas is introduced into the system to prepare magnetic organic/inorganic hybrid Janus particles.
The modification method according to claim 21, wherein the dispersion concentration of the sulfonated organic/inorganic hybrid Janus particles in deionized water is 0.01% to 1% by mass, and the magnetic precursor is two a mixture of a valence iron salt and a trivalent iron salt in a molar ratio of 1:1 to 1:2, the divalent iron salt being ferrous sulfate heptahydrate or ferrous chloride tetrahydrate, the ferric iron salt being Anhydrous ferric chloride, ferric chloride hexahydrate or iron sulphate.
The modification method according to claim 22, wherein the concentration of the ferrous sulfate heptahydrate in the aqueous solution of the magnetic precursor is 0.051% to 5.1% by mass, and the concentration of the ferric chloride It is 0.059%-5.9% by mass percentage.
A magnetic organic/inorganic hybrid Janus particle prepared by the modification method according to any one of claims 21-23.
Use of the magnetic organic/inorganic hybrid Janus particles of claim 24 as a particulate emulsifier.