CN108641039B - Coated core-shell structure composite particle and preparation method and application thereof - Google Patents

Coated core-shell structure composite particle and preparation method and application thereof Download PDF

Info

Publication number
CN108641039B
CN108641039B CN201810321453.2A CN201810321453A CN108641039B CN 108641039 B CN108641039 B CN 108641039B CN 201810321453 A CN201810321453 A CN 201810321453A CN 108641039 B CN108641039 B CN 108641039B
Authority
CN
China
Prior art keywords
shell
core
coated core
shell structure
composite particle
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201810321453.2A
Other languages
Chinese (zh)
Other versions
CN108641039A (en
Inventor
水玲玲
龚颖欣
金名亮
周国富
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
South China Normal University
Original Assignee
South China Normal University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by South China Normal University filed Critical South China Normal University
Priority to CN201810321453.2A priority Critical patent/CN108641039B/en
Publication of CN108641039A publication Critical patent/CN108641039A/en
Application granted granted Critical
Publication of CN108641039B publication Critical patent/CN108641039B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F257/00—Macromolecular compounds obtained by polymerising monomers on to polymers of aromatic monomers as defined in group C08F12/00
    • C08F257/02—Macromolecular compounds obtained by polymerising monomers on to polymers of aromatic monomers as defined in group C08F12/00 on to polymers of styrene or alkyl-substituted styrenes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/02—Making microcapsules or microballoons
    • B01J13/04—Making microcapsules or microballoons by physical processes, e.g. drying, spraying
    • B01J13/043—Drying and spraying
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/02—Making microcapsules or microballoons
    • B01J13/06—Making microcapsules or microballoons by phase separation
    • B01J13/14—Polymerisation; cross-linking
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/02—Making microcapsules or microballoons
    • B01J13/06—Making microcapsules or microballoons by phase separation
    • B01J13/14—Polymerisation; cross-linking
    • B01J13/18—In situ polymerisation with all reactants being present in the same phase
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F212/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring
    • C08F212/02—Monomers containing only one unsaturated aliphatic radical
    • C08F212/04—Monomers containing only one unsaturated aliphatic radical containing one ring
    • C08F212/06—Hydrocarbons
    • C08F212/08—Styrene
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K9/00—Use of pretreated ingredients
    • C08K9/02—Ingredients treated with inorganic substances
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K30/00—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation
    • H10K30/30—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation comprising bulk heterojunctions, e.g. interpenetrating networks of donor and acceptor material domains
    • H10K30/35—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation comprising bulk heterojunctions, e.g. interpenetrating networks of donor and acceptor material domains comprising inorganic nanostructures, e.g. CdSe nanoparticles
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C08K2003/2237—Oxides; Hydroxides of metals of titanium
    • C08K2003/2241—Titanium dioxide
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00—Specific properties of additives
    • C08K2201/011—Nanostructured additives
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K2102/00—Constructional details relating to the organic devices covered by this subclass
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/549—Organic PV cells

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Polymers & Plastics (AREA)
  • Medicinal Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Nanotechnology (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Composite Materials (AREA)
  • Inorganic Chemistry (AREA)
  • Electromagnetism (AREA)
  • Graft Or Block Polymers (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

The invention discloses a coated core-shell structure composite particle and a preparation method and application thereof, wherein the coated core-shell structure composite particle comprises a core structure, and a first shell layer, a second shell layer and a third shell layer which are sequentially coated on the core structure, wherein the core structure is titanium dioxide, the first shell layer is aluminum oxide, the second shell layer is poly (styrene-divinylbenzene), and the third shell layer is polymethyl methacrylate. The invention prepares the composite particles with the coated core-shell structure through multi-step emulsion polymerization, and can realize particle self-assembly under the induction of ultralow voltage. The prepared composite particles have excellent electrical response type through inorganic and organic material coating modification, and have good application prospect in the field of photoelectricity.

Description

Coated core-shell structure composite particle and preparation method and application thereof
Technical Field
The invention relates to the field of composite materials, in particular to a coated core-shell structure composite particle and a preparation method and application thereof.
Background
Nanoparticles refer to particles having a size on the order of nanometers (10)-9m) ultrafine particles with a size larger than the atomic cluster but smaller than common particles, and the particle size is generally between 1 and 100 nm. The nano particles have the basic characteristics of small size effect, quantum size effect, surface effect, macroscopic quantum tunneling effect and the like, so the nano particles have unique performance in the fields of light, electricity, magnetism, heat, catalysis and the like.
The inorganic material has the advantages of good strength, rigidity, heat resistance, dimensional stability, long service life and the like, but has the defect of difficult processing and forming and the like. Compared with inorganic materials, organic materials are easier to process and form, have the advantages of good structure designability and comprehensive mechanical strength, but have poor thermal stability, insufficient electronic spectrum linewidth and the like, and cannot completely meet the requirements of functional materials such as optical, electrical, magnetic and the like. Therefore, the composite material formed by the inorganic material and the organic polymer material obtained by the complementary advantages greatly meets the requirements of the functional material, and has wide development and application prospects in the fields of electronics, optics, machinery and the like.
Nano titanium dioxide (TiO)2) The functional fine inorganic material with high added value is widely applied to the fields of paint, photocatalyst, cosmetics, sensors, electronic materials and the like due to the characteristics of good weather resistance, chemical corrosion resistance, strong ultraviolet resistance and the like. TiO 22There are 3 existing forms in nature, namely: brookite, anatase, and rutile. The crystal structure determines the TiO2In nature, the rutile form is TiO2The most stable crystalline form, which is a thermodynamically stable phase, is dense in structure and has a higher refractive index, hardness, and dielectric constant than anatase. Due to TiO2The polarity of the molecule is strong, so that TiO2The surface is easy to absorb water molecules and polarize the water molecules to form surface hydroxyl groups. And nano-sized TiO2Large specific surface area and high surface energyThe agglomeration is easy to occur in the preparation and application processes, so that the excellent performance of the nano TiO can not be fully exerted, and therefore, the nano TiO is required to be treated2And carrying out surface modification treatment. Secondly, the relative dielectric constant of the titanium dioxide particles reaches 110, the value is larger, and the uniform colloidal suspension of the pure titanium dioxide particles has good electrical response only under a higher applied electric field, which is not favorable for the response of the titanium dioxide particles in the photoelectric field.
At present, spontaneous nanoparticle self-assembly or chemical self-assembly means are usually adopted for surface modification, but experimental conditions and parameters need to be strictly controlled and selected, and meanwhile, simple chemical self-assembly is not suitable for large-scale operation to obtain an ideal assembly structure. In order to make self-assembly more purposeful and controllable, physical external fields (electric fields and magnetic fields) are often introduced in the chemical self-assembly process, and the interaction between the external fields and the nanoparticles is utilized to enhance the inherent dipole moment of the substance or change the change of system energy in the self-assembly process, so as to obtain unique assembly morphology and structure.
An electric field is used as an assembly means widely adopted, and the current main research is to induce nanoparticles to move in the electric field under the action of an alternating electric field, wherein the common particles comprise gold nanoparticles, carbon black nanoparticles and SiO2And Al submicron particles and submicron or micron-scale composite particles, and obtaining structures such as one-dimensional directional arrangement, nano-scale or micron-scale lines and the like under an external alternating electric field. Wherein, the particles are generally required to be dispersed in polar solvents such as deionized water, acetone and the like, and the external electric field strength is required to be 1-16 kV/mm. Considering the influence of the external environment on the nanoparticles, the experimental facility takes a closed system as a main research object. The limitations of this approach are mainly reflected in two aspects: firstly, the length of an external electric field is large, and a test device is easy to break down; and secondly, the test environment needs to be closed, so that the requirements on test cleaning and cleanliness are increased.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention aims to provide coated core-shell structure composite particles and a preparation method and application thereof.
The technical scheme adopted by the invention is as follows:
the invention provides a coated core-shell structure composite particle which comprises a core structure, and a first shell layer, a second shell layer and a third shell layer which are sequentially coated on the core structure, wherein the core structure is titanium dioxide, the first shell layer is alumina, the second shell layer is poly (styrene-divinylbenzene), and the third shell layer is polymethyl methacrylate.
In the invention, the second shell layer is a poly (styrene-divinylbenzene) layer and is formed by polymerizing a styrene monomer and a divinylbenzene monomer under the action of an initiator.
Preferably, the core structure is a nanoparticle with a particle size of 25-100 nm.
The invention also provides a preparation method of the coated core-shell structure composite particle, which comprises the following steps:
(1) dispersing titanium dioxide particles in a solvent, adding aluminum salt, and hydrolyzing to obtain a substance A;
(2) mixing the substance A with a styrene monomer and a divinyl benzene monomer, adding an initiator and an emulsifier, and obtaining a substance B by using an emulsion polymerization method;
(3) dispersing the substance B in an emulsifier, adding a methyl methacrylate monomer, and obtaining a substance C by an emulsion polymerization method.
In the step (1), the aluminum salt forms a layer of compact aluminum oxide (Al) on the surface of the titanium dioxide particles through hydrolysis2O3) The obtained substance A is a composite particle with titanium dioxide as a core structure and aluminum oxide as a shell structure. In the step (2), under the action of an initiator, a styrene monomer and a stilbene monomer form a poly (styrene-divinylbenzene) layer on the surface of the substance A to obtain a substance B, and in the step (3), the substance C has a structure that a polymethyl methacrylate layer is coated on the surface of the substance B.
Preferably, the aluminum salt in step (1) is any one of sodium metaaluminate, aluminum chloride and aluminum sulfate.
Preferably, the initiator is an azo-type initiator or an inorganic peroxy-type initiator.
Further, the azo initiator is Azobisisobutyronitrile (AIBN), and the inorganic peroxy initiator is potassium persulfate (KPS), a water-soluble initiator.
Preferably, the emulsifier is a methanol solution to which a water-soluble polymer compound is added.
Further, the water-soluble high molecular compound is polyvinylpyrrolidone (PVP, K23-27).
Preferably, the method further comprises the step (4): and (4) dispersing the substance C obtained in the step (3) in an organic solvent, adding a surfactant, and applying an external direct current electric field for self-assembly. The invention basically completes a complete self-assembly chain structure within 30s under the applied external voltage. The local area has larger induced dipole moment under the induction action of the external electric field due to the larger particle size of the composite particles, so that a forked structure is easily formed. Along with the increase of the external voltage, the interaction of the chain structure formed by the self-assembly of the particles under the induction of the electric field is enhanced, the formation of the columnar structure is further promoted, and the development from the one-dimensional structure to the two-dimensional structure is realized. Different self-assembly structures can be obtained by changing the particle size of the core nano-particles, adjusting the applied external voltage and the light and heat effects in the environment.
Further, the organic solvent is at least one of n-undecane, simethicone, mineral oil and vegetable oil.
Further, the surfactant is span. The Span refers to Span series, and comprises Span20 (Span20), Span40 (Span40), Span60 (Span60), Span80 (Span80), Span85 (Span85) and the like.
Furthermore, the electric field intensity of the direct current electric field is less than or equal to 10V/mm. The device for applying the DC voltage in the present invention may be an open substrate having at least two electrodes or a substrate having upper and lower conductive layers, such as an open flat conductive glass device, and the distance between the electrodes is preferably 100 + -10 μm.
The coated core-shell structure composite particle has the characteristic of quick response under an ultralow electric field, has a good application prospect in the photoelectric field, and is preferably applied to a photovoltaic solar cell.
The invention has the beneficial effects that:
1. the invention provides a coated core-shell structure composite particle, which is a response material suitable for the field of electricity, can be self-assembled to form a structure with a specific appearance under an applied electric field, and has good light absorption and electron transmission performance by depositing alumina particles on the surface of titanium dioxide as an electron transmission layer. In addition, the aluminum oxide has a higher isoelectric point which is about 9.2, and is also beneficial to the response of the aluminum oxide in the photoelectric field, so that the addition of the aluminum oxide layer can improve the light absorption and electron transmission performance of the composite particles, can promote the composite particles to have the electrical response characteristic in a lower external induced electric field, and has a better application prospect in a photovoltaic solar cell.
2. Under a lower applied electric field, the nano-grade pure titanium dioxide particle dispersion suspension is in a random dispersion state and mainly takes disordered Brownian motion as a main component. The surface potential of the coated particles modified by the aluminum oxide on the surface material is positive, and the particles can be quickly gathered at the edges of the positive and negative electrodes from an initial irregular Brownian motion dispersion state under the induction of an ultra-low electric field to form an electrode edge and an intensive enrichment state on an electrode plate, and the electric field intensity required by electric response is low.
3. The specific surface energy of nano titanium dioxide is higher, in order to change the hydrophilicity and hydrophobicity of the surface of titanium dioxide, the traditional method is that the surface of titanium dioxide particles is modified by 3- (methacryloyloxy) propyl trimethoxy silane (MPS) through a silane coupling agent, and styrene is promoted to polymerize on the surface of the titanium dioxide particles by utilizing the interaction between carbon-carbon double bonds and styrene groups, so that the obtained TiO2The particle can reduce the external induced electric field to a certain extent, but the external induced electric field is still higher, and generally more than 1kV/mm is needed. The invention uses alumina layer to replace silane coupling agent, through inorganic-organic material modification, on the surface of alumina, styrene can also be effectively polymerized and modified on the surface, and the obtained composite particles can be rapidly gathered in positive and negative electricity under the induction of ultra-low electric fieldAt the extreme edges, the self-assembly of the particles is promoted due to the interaction among the particles, and finally, chain, column or comb-shaped structures and the like are formed.
4. The invention prepares the composite particle with the coated core-shell structure by multi-step emulsion polymerization, and can realize particle self-assembly under the induction of ultralow voltage. By coating and modifying the inorganic and organic materials and utilizing the synergistic effect of the materials, the external voltage required by directional arrangement formed by self-assembly of particles under the induction action of an external electric field can be effectively reduced, and the breakdown damage of a device caused by overlarge external electric field can be avoided.
Drawings
FIG. 1 is a schematic diagram of a synthetic route of the coated core-shell structure composite particle of the present invention;
FIG. 2 is a schematic diagram of a synthetic structure of the coated core-shell structure composite particle of the present invention;
FIG. 3 is a schematic view of a TEM structure of the coated core-shell structure composite particle of the present invention;
fig. 4 is a schematic diagram of a top view and a front view of the self-assembly of the ultralow voltage induced cladding core-shell structure composite particles in embodiment 1 of the present invention;
FIG. 5 is a time effect diagram of the self-assembly of the clad core-shell structure composite particles of the present invention at an interval of 10s under the induction of an ultra-low voltage of 1.3V/mm;
FIG. 6 is a time effect diagram of the self-assembly of the clad core-shell structure composite particles of the present invention at an interval of 10s under the induction of ultra-low voltage of 0.7 kV/mm;
FIG. 7 is a time effect diagram of the self-assembly of the coated core-shell structure composite particles of the present invention at an interval of 10s under the induction of ultra-low voltage of 0.9 kV/mm;
fig. 8 is a voltage effect diagram of the coated core-shell structure composite particles of the present invention after self-assembly for 10s under induction of different voltages.
Detailed Description
The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the objects, features and effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention.
Example 1
Referring to fig. 1 and fig. 2, this embodiment provides a preparation method of a coated core-shell structure composite particle, including the following steps:
2.0g of titanium dioxide nano-particles are annealed and calcined at 500 ℃ for 10 hours, then dispersed in a 50mL three-neck flask containing 10g of deionized water to obtain a suspension mixed solution A, and the pH value of the solution is adjusted to 9-10 by using a 20% NaOH solution. Stirring uniformly under a magnetic stirrer, wherein the stirring speed is 400r/min, heating to 75 ℃, and dropwise adding 6mL of 10% NaAlO within 60min2Adjusting pH value of the solution with 20% HCl solution, maintaining the pH value at 8-9, adjusting pH value to promote hydrolysis of sodium metaaluminate solution, maintaining the pH value at 7-8, reacting at constant temperature of 75 deg.C for 60min to obtain TiO2/Al2O3Nanoparticles (substance a).
Grinding the prepared substance A, and preparing a crosslinked styrene layer by using an in-situ polymerization method, wherein the method comprises the following specific steps: taking 0.05g of the substance A, mixing with 0.3g of styrene (St) and 0.017g of Divinylbenzene (DVB), carrying out ultrasonic dispersion for 20min to obtain a mixed solution, adding the mixed solution into a methanol solution of 2.4 wt% of polyvinylpyrrolidone (PVP), carrying out ultrasonic emulsification dispersion treatment for 30min in an ice bath environment after carrying out ultrasonic dispersion for 5 min, pouring into a three-neck flask, adding 0.01g of azobisisobutyronitrile initiator under the protection of nitrogen, stirring at the speed of 800r/min, heating to 75 ℃, and keeping stirring for reaction for 6 hours to obtain a substance B.
Substance B was further modified by suspension-emulsion polymerization: dispersing the obtained substance B in a methanol solution of 2.4 wt% of polyvinylpyrrolidone (PVP), quickly adding 70 mu L of methyl methacrylate, maintaining the stirring speed, reacting for 14 hours at a constant temperature of 75 ℃, aging the mixture for 2 hours, repeatedly washing with deionized water for three times, drying at a vacuum temperature of 50 ℃, and grinding to obtain a substance C, namely the coated core-shell structure composite particle. The coated core-shell structure composite particles prepared by the method are characterized, and a TEM (transmission electron microscope) image is shown in FIG. 3. As can be seen from FIG. 3, the shell thickness of the coated core-shell structure composite particle prepared by the invention is about 3 +/-1 nm, and the coated core-shell structure composite particle mainly aims at complete coating of a single particle, has an obvious core-shell interface and can form a good coating structure.
Example 2
0.0065g of the coated core-shell structure composite particles prepared in the example 1 are dispersed in 5m L98% n-undecane, a nonionic surfactant LSpan80 is added according to the mass ratio of 9:1, and the uniform suspension white emulsion is obtained by ultrasonic dispersion. In a device with an electrode spacing of about 100 mu m, the ultralow direct current voltage of 0V and the actual output value of 0.13V are set, and the values are recorded every 10s, so that the coated core-shell structure composite particles can be rapidly self-assembled between two polar plates to form a chain structure. Fig. 4 shows a schematic diagram of the induced encapsulation core-shell structure composite particles self-assembled into a chain structure in this embodiment, and fig. 4(a) and 4(b) show a top view and a front view of the self-assembly schematic diagram, respectively. When an external electric field is applied, the coated core-shell structure composite particles are subjected to the polarization effect of the external electric field, and because the charge distribution on the surface interface of the composite particles is uneven, induced dipoles are generated, and the composite particles are induced to generate electric field motion migration under the action of the electric field force, as shown in fig. 4 (a). In a overlook observation area, due to mutual attraction of heterogeneous charges between the composite particles, a short chain structure is formed at two poles and is continuously increased; as the chain length increases, the interaction between the chains increases, and interchain entanglement occurs in the middle of the two electrodes, thereby forming a tightly cross-linked entangled structure, and the resulting induced self-assembled structure is observed from the front in the region between the two electrodes, so that a chain-like structure can be obtained, as shown in fig. 4 (b).
Fig. 5(a) - (f) are optical microscope images from applied voltage to applied voltage 50s at an interval of 10s under an ultra-low electric field of 1.3V/mm. When voltage is applied for 10s, the coated core-shell structure composite particles are rapidly gathered at two ends of the electrode, and a large number of short chain structures appear and extend towards the opposite electrode of the electric property; and basically completing ultralow voltage induced self-assembly within 20s to form a chain structure between the two electrodes. The coated core-shell structure composite particle has the advantage of quick response under ultralow voltage, and has a good application prospect in the photoelectric field such as photovoltaic solar cells.
Example 3
This example is the same as example 2 except that the ultra-low direct current voltage was changed from 0V to 70V, the electric field was 0.7kV/mm, and optical microscope images obtained from the initial applied voltage to the applied voltage for 50s at an interval of 10s were shown in FIGS. 6(a) - (f). And (3) at the beginning of applying voltage for 10s, rapidly gathering particles at two ends of the electrodes, basically finishing ultralow voltage induced self-assembly to form a chain structure between the two electrodes, and inducing the formed chain structure to cross-link and wind in the middle area of the two polar plates to form a comb-shaped structure on the two polar plates, wherein the middle part of the comb-shaped structure is tightly wound into a columnar structure.
Example 4
This example is the same as example 2 except that the ultra-low direct current voltage was changed from 0V to 90V, the electric field was 0.9kV/mm, and optical microscope images obtained from the initial applied voltage to the applied voltage for 50s at an interval of 10s were shown in FIGS. 7(a) - (f). And (3) at the beginning of applying voltage for 10s, rapidly gathering particles at two ends of the electrodes, basically finishing the ultra-low voltage induced self-assembly to form a chain structure between the two electrodes, and performing induction on the formed chain structure to cross-link and wind in the middle area of the two electrode plates. Along with the increase of voltage, the interaction of the composite particles under the action of an electric field is obviously enhanced, short chains formed by the particles begin to be tightly wound under the strong interaction at the two polar plate ends, the formed comb-shaped structures are reduced, and the columnar structures are obviously increased.
Example 5
Taking the coated core-shell structure composite particles prepared in example 1, observing the conditions of inducing the self-assembly of the composite particles under different ultra-low voltages according to the method of example 2, as shown in fig. 8, fig. 8(a) - (e) represent the effect graphs under the electric fields of 0.0013kV/mm, 0.01kV/mm, 0.1kV/mm, 0.5kV/mm and 1kV/mm for 10s respectively. As can be seen from the figure, with the increase of the value of the applied ultralow voltage, the induced force on the composite particles is increased, and the formed chain-shaped structure is obviously cross-linked and wound in the middle area of the bipolar plate under the induction action.
Example 6
Comparative example 1
KimM-H, BaeD-H, ChoiH-J, etc. in ethanol solution by oxidation polymerization method to obtain poly diphenylamine particle, particles dispersed in silicone oil, particles volume fraction of 5% of the liquid to be tested, in the electric field intensity of 3.3kV/mm (applied external voltage about 400V), along the electric field line direction to form single chain, but the interaction force between chains is small, chain spiral winding degree is low. (reference Kim, M.H.; Bae, D.H.; Choi, H.J.; Seo, Y., Synthesis of semiconducting poly (diphenylamine) polymers and analysis of the electron electrophoretic properties. Polymer 2017,119,40-49.)
Comparative example 2
The core-shell result particles prepared by Cho M-S, Cho Y-H, Choi H-J and the like, which take polymethyl methacrylate microspheres as inner cores and polyaniline as nano shell layers, have small conductivity, are polarized on particle surface interfaces under the action of an external electric field, and quickly form a chain structure in 20S along the direction of electric field lines under the action of an electric field strength of 2kV/mm, but the obtained composite particles have larger particle size and weaker interaction force among chains. (references Min S.Cho, Y.H.C., Young J.Choi, Myung S.Jhon, Synthesis and electrophoretic Properties of polyurethane-Coated Poly (methyl methacrylate) Microsphere: Size Effect.Langmuir 2003,19, 5875-cake 5881.)
Comparative example 3
Katsunomi T, T.W, Atsushi K and the like research the behavior of nano titanium dioxide particles under the action of an external electric field, the particles are dispersed in silicone oil to obtain a mixed liquid to be detected with the particle concentration of 30 wt.%, a direct current electric field is applied to the liquid to be detected, the electric field strength is in the range of 1.0-16 kV/mm, the particles quickly form a chain-shaped structure along the direction of electric field lines, the viscosity of the mixed liquid to be detected is obviously changed after the external electric field is applied, but the applied external electric field is large, so that an ITO electrode is easily broken down to damage a device. (reference Katsufumi T., T.W., Atsushi K., Ryuuchi
A.,Electro-rheological behavior of suspension composed of titanium dioxide nano-particles.Sensors and Actuators A 2004,112,376-380.)
Through comparison of examples and comparative examples 1 to 3, it is shown that the coated core-shell structure composite particles prepared by the invention, which use titanium dioxide as the core, can be self-assembled to form a specific structure under a lower electric field (the electric field strength can be less than 0.2V/mm), and have the advantages that the coated core-shell structure composite particles are different from the prior art, the required particle concentration is high, and a self-assembled structure with chains not tightly wound with each other can be formed under a higher electric field (the electric field strength is usually more than or equal to 1 kV/mm). The advantages of low driving voltage, high response speed, low cost and the like have better application prospect in the photoelectric field (light valves and intelligent windows).
Example 7
2.0g of titanium dioxide nano-particles are annealed and calcined at 500 ℃ for 10 hours, then dispersed in a 50mL three-neck flask containing 10g of deionized water to obtain a suspension mixed solution A, and the pH value of the solution is adjusted to 9-10 by using a 20% NaOH solution. Stirring uniformly under a magnetic stirrer at a stirring speed of 400r/min, heating to 75 ℃, and dropwise adding 6mL of 10% AlCl within 60min3Adjusting pH value of the solution with 20% HCl solution, maintaining the pH value at 8-9, adjusting pH value to promote hydrolysis of sodium metaaluminate solution, maintaining the pH value at 7-8, reacting at constant temperature of 75 deg.C for 60min to obtain TiO2/Al2O3Nanoparticles (substance a).
Grinding the prepared substance A, and preparing a crosslinked styrene layer by using an in-situ polymerization method, wherein the method comprises the following specific steps: taking 0.05g of the substance A, mixing with 0.3g of styrene (St) and 0.017g of Divinylbenzene (DVB), carrying out ultrasonic dispersion for 20min to obtain a mixed solution, adding the mixed solution into a methanol solution of 0.16 wt% of polyvinylpyrrolidone (PVP), carrying out ultrasonic emulsification dispersion treatment for 30min in an ice bath environment after carrying out ultrasonic treatment for 5 min, pouring into a three-neck flask, adding 0.01g of potassium persulfate initiator under the protection of nitrogen, stirring at the speed of 800r/min, heating to 75 ℃, and keeping stirring for reaction for 6 hours to obtain a substance B.
Substance B was further modified by suspension-emulsion polymerization: dispersing the obtained substance B in 0.16 wt% of methanol solution of polyvinylpyrrolidone (PVP), quickly adding 70 mu L of methyl methacrylate, maintaining the stirring speed, reacting for 14 hours at a constant temperature of 75 ℃, aging the mixture for 2 hours, repeatedly washing with deionized water for three times, drying at a vacuum temperature of 50 ℃, and grinding to obtain a substance C, namely the coated core-shell structure composite particle.

Claims (10)

1. The coated core-shell structure composite particle is characterized by comprising a core structure, and a first shell layer, a second shell layer and a third shell layer which are sequentially coated on the core structure, wherein the core structure is titanium dioxide, the first shell layer is aluminum oxide, the second shell layer is poly (styrene-divinylbenzene), and the third shell layer is polymethyl methacrylate.
2. The coated core-shell structure composite particle according to claim 1, wherein the core structure is a nanoparticle having a particle size of 25 to 100 nm.
3. The preparation method of the coated core-shell structure composite particle according to claim 1 or 2, characterized by comprising the following steps:
(1) dispersing titanium dioxide particles in a solvent, adding aluminum salt, and hydrolyzing to obtain a substance A;
(2) mixing the substance A with a styrene monomer and a divinyl benzene monomer, adding an initiator and an emulsifier, and obtaining a substance B by using an emulsion polymerization method;
(3) dispersing the substance B in an emulsifier, adding a methyl methacrylate monomer, and obtaining a substance C by an emulsion polymerization method.
4. The method for preparing the coated core-shell structure composite particle according to claim 3, wherein the aluminum salt is any one of sodium metaaluminate, aluminum chloride and aluminum sulfate.
5. The method for preparing the coated core-shell structure composite particles according to claim 3, wherein the initiator is an azo initiator or an inorganic peroxy initiator.
6. The method for preparing the coated core-shell structure composite particle according to claim 3, wherein the emulsifier is a methanol solution to which a water-soluble polymer compound is added.
7. The preparation method of the coated core-shell structure composite particle according to claim 3, further comprising the step (4): and (4) dispersing the substance C obtained in the step (3) in an organic solvent, adding a surfactant, and applying a direct current electric field for self-assembly.
8. The method for preparing the coated core-shell structure composite particle according to claim 7, wherein the organic solvent is at least one of n-undecane, dimethicone, mineral oil, and vegetable oil.
9. The preparation method of the coated core-shell structure composite particle according to claim 7 or 8, wherein the electric field intensity of the direct current electric field is less than or equal to 1 kV/mm.
10. The use of the coated core-shell structured composite particles according to claim 1 or 2 in the field of optoelectronics.
CN201810321453.2A 2018-04-11 2018-04-11 Coated core-shell structure composite particle and preparation method and application thereof Active CN108641039B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810321453.2A CN108641039B (en) 2018-04-11 2018-04-11 Coated core-shell structure composite particle and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810321453.2A CN108641039B (en) 2018-04-11 2018-04-11 Coated core-shell structure composite particle and preparation method and application thereof

Publications (2)

Publication Number Publication Date
CN108641039A CN108641039A (en) 2018-10-12
CN108641039B true CN108641039B (en) 2021-02-26

Family

ID=63746071

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810321453.2A Active CN108641039B (en) 2018-04-11 2018-04-11 Coated core-shell structure composite particle and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN108641039B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110281322A (en) * 2019-05-23 2019-09-27 肥西县创玺建材科技有限公司 A kind of preparation method keeping the temperature high-strength plywood
CN110394129B (en) * 2019-08-13 2022-04-01 南京理工大学 Automatic control preparation method of ultra-uniform hollow microspheres
CN112033938B (en) * 2020-09-11 2022-09-23 华南师范大学 Visual sensor based on liquid crystal molecule self-assembly structure and construction method and application thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105646759A (en) * 2014-12-01 2016-06-08 陶氏环球技术有限责任公司 Phosphorus acid functionalized opaque polymer
CN105924569A (en) * 2016-05-16 2016-09-07 昆明理工大学 Preparing method for multi-core wrapped type compound microspheres
CN106847518A (en) * 2017-03-27 2017-06-13 中国科学院化学研究所 A kind of dye-sensitized solar cell anode and preparation method thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105646759A (en) * 2014-12-01 2016-06-08 陶氏环球技术有限责任公司 Phosphorus acid functionalized opaque polymer
CN105924569A (en) * 2016-05-16 2016-09-07 昆明理工大学 Preparing method for multi-core wrapped type compound microspheres
CN106847518A (en) * 2017-03-27 2017-06-13 中国科学院化学研究所 A kind of dye-sensitized solar cell anode and preparation method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
模板技术制备介观结构材料(英文);牛忠伟等;《中国科学院研究生院学报》;20051115(第06期);773-776 *

Also Published As

Publication number Publication date
CN108641039A (en) 2018-10-12

Similar Documents

Publication Publication Date Title
CN108641039B (en) Coated core-shell structure composite particle and preparation method and application thereof
Wang et al. Double template assisting synthesized core–shell structured titania/polyaniline nanocomposite and its smart electrorheological response
CN103193916B (en) Preparation method of polymeric microspheres for electrophoretic display
Yin et al. Titanate nano-whisker electrorheological fluid with high suspended stability and ER activity
CN101089164B (en) Polar molecule type electric rheologic liquid
Chae et al. Synthesized palygorskite/polyaniline nanocomposite particles by oxidative polymerization and their electrorheology
Guo et al. Preparation of a novel nanocomposite of polyaniline core decorated with anatase-TiO2 nanoparticles in ionic liquid/water microemulsion
CN1792445A (en) Nanometer, composite semiconductor photocatalyst, and its prepn. method
Gao et al. Hollow submicron-sized spherical conducting polyaniline particles and their suspension rheology under applied electric fields
Wu et al. Preparation and electrorheological characteristics of uniform core/shell structural particles with different polar molecules shells
Park et al. Preparation and electrophoretic response of poly (methyl methacrylate-co-methacrylic acid) coated TiO2 nanoparticles for electronic paper application
Wen et al. Clip-like polyaniline nanofibers synthesized by an insitu chemical oxidative polymerization and its strong electrorheological behavior
Lee et al. Carbon sphere as a black pigment for an electronic paper
CN106010736B (en) A kind of anisotropic titanium oxide/polyaniline nano-composite material ER fluid and preparation method thereof
Liu et al. Electrorheological response of polyaniline and its hybrids
Oh et al. Characterization and electrorheological response of silica/titania-coated MWNTs synthesized by sol–gel process
CN1473883A (en) Method for increasing dispersiveness of inorganic oxide powder in organic medium
Wang et al. Titanium oxide nanoparticle modified with chromium ion and its giant electrorheological activity
Wang et al. The preparation and smart electrorheological behavior of MOF-Ti@ PANI core-shell nanoparticles
Chen et al. Silica-based ionogels containing imidazolium ionic liquids and their electrorheological responses at room and elevated temperatures
CN106867629B (en) Electrorheological fluid and preparation method thereof
Cheng et al. Strong electrorheological performance of smart fluids based on TiO2 particles at relatively low electric field
Qiao et al. Effect of surface modification of SiO 2@ TiO 2 core–shell particles on the structural colour under an electric field
Kim et al. Core–shell structured poly (methyl methacrylate)-coated zirconium dioxide nanoparticle and its dispersion stability
Kaur et al. Electrical and mechanical behavior of polymethyl methacrylate/cadmium sulphide composites

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant