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CN116120694A - Thermal expansion microsphere with core-shell structure and preparation method thereof - Google Patents

Thermal expansion microsphere with core-shell structure and preparation method thereof Download PDF

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CN116120694A
CN116120694A CN202211642485.5A CN202211642485A CN116120694A CN 116120694 A CN116120694 A CN 116120694A CN 202211642485 A CN202211642485 A CN 202211642485A CN 116120694 A CN116120694 A CN 116120694A
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acrylate
meth
monomer
combination
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郑从光
方璞
秦佃斌
鲁航
陈佳乐
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Wanhua Chemical Group Co Ltd
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Wanhua Chemical Group Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/16—Making expandable particles
    • 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
    • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
    • C08F220/42—Nitriles
    • C08F220/44—Acrylonitrile
    • 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
    • C08F236/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds
    • C08F236/02—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds
    • C08F236/04—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated
    • C08F236/14—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated containing elements other than carbon and hydrogen
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2309/00—Characterised by the use of homopolymers or copolymers of conjugated diene hydrocarbons
    • C08J2309/02—Copolymers with acrylonitrile
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2333/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers
    • C08J2333/18—Homopolymers or copolymers of nitriles
    • C08J2333/20—Homopolymers or copolymers of acrylonitrile

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Abstract

The invention provides a thermal expansion microsphere with a core-shell structure and a preparation method thereof, wherein the thermal expansion microsphere comprises a core and a shell layer, the core comprises a foaming agent, the shell layer comprises a thermoplastic polymer, and the preparation monomer of the thermoplastic polymer comprises a conjugated diene monomer; by selecting a thermoplastic polymer as a shell material of the thermal expansion microsphere and limiting the preparation monomer of the thermoplastic polymer to comprise conjugated diene monomer, the obtained thermal expansion microsphere with the core-shell structure has low initial expansion temperature, high expansion degree, excellent solvent resistance and wider application field.

Description

Thermal expansion microsphere with core-shell structure and preparation method thereof
Technical Field
The invention belongs to the technical field of polymer microspheres, and in particular relates to a thermal expansion microsphere with a core-shell structure and a preparation method thereof.
Background
Thermally expandable microspheres refer to microspheres in which the shell softens when heated, and the blowing agent contained therein volatilizes, causing an increase in internal pressure, thereby expanding the microspheres. Thermally expandable microspheres are used as blowing agents, light fillers, etc. in many different fields, for example in the fields of elastomers, thermoplastic elastomers, polymers, putties, primers, plastisols, printing inks, papers, explosives, and cable insulation.
At present, in order to prevent the foaming agent in the microsphere from leaking in the foaming expansion process, the shell layer of the thermal expansion microsphere needs to have excellent air tightness, and in order to improve the ductility of the shell layer of the thermal expansion microsphere, a multifunctional third monomer is generally introduced into the preparation monomer of the shell layer; in addition, in certain applications, it is desirable that the thermally expandable microspheres expand at a lower temperature, which requires a thermally expandable microsphere having a low initial expansion temperature (tststsrt), and a higher expansion (maximum expansion ratio) for the thermally expandable microsphere.
CN101378831a discloses a thermally expandable thermoplastic microsphere comprising a polymer shell made of ethylenically unsaturated monomers containing 40 to 70 wt% acrylonitrile, 5 to 40 wt% methacrylonitrile, 10 to 50 wt% monomers selected from the group consisting of esters of acrylic acid, methacrylic acid and mixtures thereof, encapsulating a propellant comprising at least one of methane, ethane, propane, isobutane, n-butane and neopentane, the invention further relates to the preparation and use of such a microsphere. Although the invention provides the low-temperature foaming microsphere obtained without halogen monomers, the preparation monomers of the shell layer are all polar monomers, so that the obtained microsphere has poor tolerance to polar solvents, can not maintain expansion performance in a scene containing polar organic solvents, and limits the application of the microsphere.
Therefore, developing a thermally expandable microsphere with low initial expansion temperature, high expansion ratio and excellent solvent resistance is an urgent technical problem in the art.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a thermal expansion microsphere with a core-shell structure and a preparation method thereof, wherein the thermal expansion microsphere takes a thermoplastic polymer as a shell layer, and preparation monomers of the thermoplastic polymer comprise conjugated diene monomers, so that the obtained thermal expansion microsphere with the core-shell structure has low initial expansion temperature, high expansion multiplying power, excellent solvent resistance and excellent thermal expansion performance under the condition of containing a polar organic solvent.
To achieve the purpose, the invention adopts the following technical scheme:
in a first aspect, the present invention provides a thermally expandable microsphere having a core-shell structure, the thermally expandable microsphere comprising a core and a shell, the core comprising a blowing agent;
the shell layer comprises a thermoplastic polymer, and the preparation monomer of the thermoplastic polymer comprises conjugated diene monomer.
The core of the core-shell structure comprises a foaming agent, the shell layer of the core-shell structure comprises a thermoplastic polymer, and the preparation monomer of the thermoplastic polymer comprises a conjugated diene monomer, so that the obtained thermal expansion microsphere with the core-shell structure has low initial expansion temperature, high expansion degree and excellent solvent resistance under the condition of not adopting halogen-containing monomers, and has wider application fields.
Preferably, the mass percentage of the shell layer in the thermally expandable microspheres is 70 to 95%, for example 72%, 74%, 76%, 78%, 80%, 82%, 85%, 88%, 91% or 94%, etc., and more preferably 70 to 90%.
The particle diameter of the thermally expandable microspheres is preferably 1 to 500. Mu.m, for example, 10 μm, 50 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm or 450 μm, etc., more preferably 1 to 200. Mu.m, still more preferably 3 to 100. Mu.m, still more preferably 5 to 50. Mu.m.
Preferably, the blowing agent comprises isobutane.
Preferably, the blowing agent further comprises other alkanes having a boiling point of not more than 120 ℃ (e.g., 110 ℃, 100 ℃, 90 ℃, 80 ℃, 70 ℃, 60 ℃, 50 ℃, etc.) in addition to isobutane.
Preferably, the other alkanes having a boiling point not higher than 120 ℃ comprise any one or a combination of at least two of isopentane, n-pentane, n-hexane, cyclohexane, petroleum ether, n-heptane or isooctane.
Preferably, the blowing agent comprises greater than 20% by mass isobutane, for example 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36% or 38% etc.
Preferably, the glass transition temperature of the shell layer is not higher than 120 ℃, for example, 110 ℃, 100 ℃, 90 ℃, 80 ℃, 70 ℃, 60 ℃, 50 ℃, or the like, and more preferably 50 to 120 ℃.
Preferably, the conjugated diene monomer comprises any one or a combination of at least two of 1, 3-butadiene, 1, 3-pentadiene, isoprene or cyclopentadiene.
Preferably, the thermoplastic polymer is prepared with a mass percent of conjugated diene monomer in the monomer of greater than 10%, for example 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26% or 28%, etc., more preferably greater than 20%.
As a preferred technical scheme of the invention, the mass percent of the conjugated diene monomer in the preparation monomer of the thermoplastic polymer is more than 10 percent, and if the content of the conjugated diene monomer is too low, the glass transition temperature of a shell layer cannot be effectively reduced, so that the initial expansion temperature of the thermally expandable microspheres is higher.
Preferably, the preparation monomers of the thermoplastic polymer further comprise other mono-and/or poly-functional monomers containing carbon-carbon double bonds than the conjugated diene monomer.
Preferably, the other monofunctional monomer containing carbon-carbon double bonds comprises any one or a combination of at least two of acrylonitrile monomers, acrylic ester monomers, vinyl pyridine, styrene monomers or vinyl ester monomers.
Preferably, the acrylonitrile monomer comprises any one or a combination of at least two of acrylonitrile, methacrylonitrile, fumaronitrile, crotononitrile, alpha-chloroacrylonitrile or alpha-ethoxyacrylonitrile, and further preferably acrylonitrile and/or methacrylonitrile.
As a preferable technical scheme of the invention, acrylonitrile and/or methacrylonitrile are added to match with conjugated diene monomer, so that the shell layer of the obtained thermal expansion microsphere has excellent barrier property and can better encapsulate the foaming agent of the core.
Preferably, the acrylic monomer comprises any one or a combination of at least two of methyl acrylate, ethyl acrylate, methyl methacrylate, isobornyl methacrylate and ethyl methacrylate.
Preferably, the vinyl ester monomer comprises vinyl acetate.
Preferably, the styrenic monomer comprises styrene and/or alpha-methylstyrene.
Preferably, the other carbon-carbon double bond containing polyfunctional monomers include at least one of divinylbenzene, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1, 4-butanediol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, glycerol di (meth) acrylate, 1, 3-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1, 10-decanediol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol hexa (meth) acrylate, dimethyloltricyclodecane di (meth) acrylate, triallyl formal tri (meth) acrylate, allyl methacrylate, trimethylolpropane tri (meth) acrylate, tributyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 3-acryloxyethylene glycol mono (meth) acrylate, triallyl acrylate, or a combination of at least two of the above.
Preferably, the polyethylene glycol di (meth) acrylate comprises any one or a combination of at least two of PEG #200 di (meth) acrylate, PEG #400 di (meth) acrylate, or PEG #600 di (meth) acrylate.
Preferably, the mass percentage of the other polyfunctional monomer containing carbon-carbon double bonds in the preparation monomer of the thermoplastic polymer is 0.1 to 1%, for example 0.2%, 0.4%, 0.6% or 0.8%, etc., and more preferably 0.2 to 0.5%.
In a second aspect, the present invention provides a method for preparing thermally expandable microspheres according to the first aspect, the method comprising the steps of:
(1) Mixing a foaming agent, a preparation monomer of a thermoplastic polymer and an initiator to obtain an oil phase mixture;
(2) And (3) adding the oil phase mixture obtained in the step (1) into an aqueous phase medium for reaction to obtain the thermal expansion microsphere with the core-shell structure.
In the invention, firstly, a foaming agent, a preparation monomer of a thermoplastic polymer and an initiator are mixed to form an oil phase mixture, then the oil phase mixture is mixed with an aqueous phase medium to form an oil phase mixture as a disperse phase, the aqueous phase medium is a stable oil-in-water emulsion of a continuous phase, and then the polymer is generated under the condition of the initiator, so that the thermal expansion microsphere with a core-shell structure can be formed.
Preferably, the initiator of step (1) comprises an organic peroxide-based initiator and/or an azo-based initiator, further preferably any one or a combination of at least two of behenyl peroxydicarbonate, di (4-t-butylcyclohexyl) peroxydicarbonate, dioctyl peroxide, dibenzoyl peroxide, dilauroyl peroxide, didecanoyl peroxide, t-butyl peracetate, per-month Gui Xianshu butyl, benzoin t-butyl, t-butyl hydroperoxide, cumene ethyl peroxy, diisopropyl hydroxydicarboxylic acid ester, 2' -azobisisoheptonitrile, 2' -azobisisobutyronitrile, 1' -azobis (cyclohexane-1-carbonitrile), dimethyl 2,2' -azobis (2-methylpropionate) or 2,2' -azobis (2-methyl-N- (2-hydroxyethyl) propionamide).
Preferably, the aqueous medium comprises a combination of water, a solid suspending agent and a water-soluble salt.
As a preferred technical solution of the present invention, in order to reduce dissolution and diffusion of the preparation monomer of the thermoplastic polymer in the aqueous medium, it is necessary to add a water-soluble salt, and at the same time, in order to reduce polymerization of the preparation monomer dissolved in the aqueous medium, it is necessary to add a water-soluble free inhibitor (sodium nitrite) in the aqueous phase to promote polymerization of the preparation monomer inside the droplets, and to avoid wall sticking, agglomeration, deslagging, etc. caused by self-polymerization of the preparation monomer free in the aqueous phase, a solid suspending agent is added in combination to ensure a good suspension stabilizing effect, and the solid suspending agent is mainly located on the outer surface of the shell of the thermally expandable microsphere, and in some cases, the solid suspending agent may be washed away in the post-treatment stage, so that the final product is substantially free of the solid suspending agent.
Preferably, the solid suspending agent comprises any one or a combination of at least two of silica, chalk, bentonite, starch, crosslinked polymers, methylcellulose, gum agar, hydroxypropyl methylcellulose, carboxymethyl cellulose, colloidal clay, calcium phosphate, calcium carbonate, magnesium hydroxide, barium sulphate, calcium oxalate, aluminium hydroxide, ferric hydroxide, zinc hydroxide, nickel hydroxide or manganese hydroxide.
Preferably, the water soluble salts include sodium chloride and sodium nitrite.
Preferably, the aqueous medium further comprises a stabilizing aid.
As a preferable technical scheme of the invention, in order to further improve the suspension effect, a stabilizing auxiliary agent can be added into the aqueous phase medium.
Preferably, the stabilizing aid comprises any one or a combination of at least two of polyvinylpyrrolidone, sulfonated polystyrene, alginate carboxymethyl fibers, tetramethyl ammonium hydroxide, tetramethyl ammonium chloride, water-soluble condensates of diethanolamine with adipic acid, water-soluble condensates of ethylene oxide, urea with formaldehyde, polyethylenimine, gelatin, casein, albumin, gelatin proteins, soaps, alkyl sulfates or alkyl sulfonates.
Preferably, the temperature of the reaction is 40 to 80 ℃, for example 45 ℃, 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃, 75 ℃, or the like.
Preferably, the reaction time is 5 to 30 hours, for example 10 hours, 15 hours, 20 hours or 25 hours, etc.
Preferably, the reaction further comprises the steps of filtering and drying after the reaction is finished.
Preferably, the method of filtration comprises any one or a combination of at least two of bed filtration, positive/negative pressure filtration or spin-on filtration.
Preferably, the method of drying comprises any one or a combination of at least two of spray drying, tunnel drying, rotary drying, drum drying, flash drying, palladium drying or fluid bed drying.
Compared with the prior art, the invention has the following beneficial effects:
the heat expansion microsphere with the core-shell structure provided by the invention comprises a core and a shell, wherein the core comprises a foaming agent, the shell comprises a thermoplastic polymer, and the preparation monomer of the thermoplastic polymer comprises a conjugated diene monomer; by selecting a thermoplastic polymer as a shell material of the thermal expansion microsphere and limiting the preparation monomer of the thermoplastic polymer to comprise conjugated diene monomer, the obtained thermal expansion microsphere with the core-shell structure has low initial expansion temperature, high expansion degree, excellent solvent resistance and wider application field.
Detailed Description
The technical scheme of the invention is further described by the following specific embodiments. It will be apparent to those skilled in the art that the examples are merely to aid in understanding the invention and are not to be construed as a specific limitation thereof.
Preparation example 1
An aqueous medium, the preparation method of which comprises: 100g of sodium chloride, 10g of silicon dioxide water dispersing agent (the mass content of silicon dioxide is 30%), 0.2g of polyvinylpyrrolidone and 0.5g of sodium nitrite are added into 500g of deionized water, and the aqueous medium is obtained by stirring and mixing uniformly.
Examples 1 to 6 and comparative examples 1 to 5
A thermal expansion microsphere with a core-shell structure, wherein the core is isobutane, and the shell layer is a thermoplastic polymer;
the preparation method comprises the following steps:
(1) 50g of isobutane, a preparation monomer of a thermoplastic polymer (specific composition and amount of the preparation monomer of the thermoplastic polymer are shown in Table 1), 0.6g of ethylene glycol dimethacrylate and 0.8g of lauroyl peroxide were mixed to obtain an oil phase mixture;
(2) Adding the oil phase mixture obtained in the step (1) into a water phase medium (preparation example 1), forming an oil-in-water emulsion after mechanical high-speed dispersion at 5000rpm, transferring the oil-in-water emulsion into a reaction kettle, filling nitrogen into the reaction kettle until the pressure of the system is 0.8MPa, then reacting for 20 hours at 60 ℃ under the stirring condition of 500rpm, filtering, washing for 3 times with deionized water, and drying to obtain the heat expansion microsphere with the core-shell structure;
the specific composition and amount of the preparation monomer of the thermoplastic polymer added in step (1) are shown in table 1:
TABLE 1
Figure BDA0004008183790000081
Performance test:
(1) Particle size: laser light scattering measurement was performed on a wet sample of thermally expanded microspheres on a Bettersize 2000LD laser particle size analyzer, with average particle size expressed as median diameter D50 in volume diameter; particle size distribution is expressed as SPAN, meaning span= (D90-D10)/D50;
(2) Expansibility: the measurements were carried out on a static thermo-mechanical analyzer (TMA) model Metreler TMA/SDTA2+ test method of 15 ℃/min.
The test steps are as follows: adding 1mg of thermally-expanded microspheres into a 150 mu L ceramic crucible, adding a gasket with a matched diameter above the microsphere layer, preparing a sample, measuring the height of the sample in a state that a force of 0.06N is applied to the sample from above by a presser, heating the sample from 20 ℃ to 300 ℃ at a heating rate of 15 ℃/min in a state that a force of 0.06N is applied by the presser, and measuring the displacement of the presser in the vertical direction; the displacement start temperature in the positive direction was set as the expansion start temperature (Tstart), the temperature at which the maximum displacement amount was exhibited was set as the maximum expansion temperature (Tmax), and the ratio of the maximum height of the expansion process to the initial sample height was set as the expansion ratio.
(3) Solvent resistance (swell retention): the thermally expanded microspheres were immersed completely in a dimethyl carbonate solvent, immersed at 60℃for 24 hours, taken out and dried. 1mg of the microspheres were subjected to the above expansion property test on a TMA instrument, and the expansion ratio was N 0 The same test was performed using thermally expanded microspheres that had not undergone solvent impregnation treatment, expansion ratio N 1 Expansion performance retention ratio before and after the impregnation of the microspheres with the solvent=n 0 /N 1 The larger the value of 100% is, the higher the swelling retention of the microspheres after soaking in an organic solvent is, and the better the solvent resistance is.
The thermally expandable microspheres obtained in examples 1 to 6 and comparative examples 1 to 5 were subjected to the test according to the above-described test method, and the test results are shown in table 2:
TABLE 2
Figure BDA0004008183790000091
Figure BDA0004008183790000101
From the data in table 2, it can be seen that: the thermal expansion microspheres provided in examples 1 to 4 have D50 of 9 to 12 μm, SPAN of 1.21 to 1.35, tstart of 83 to 95 ℃, tmax of 120 to 135 ℃, expansion ratio of 90 to 96 and expansion retention of 25 to 49%.
As can be seen from the data of comparative examples 1 to 4 and comparative examples 1 to 5, the expansion retention rates of the thermally expandable microspheres prepared from the preparation monomers without the conjugated diene as the shell layer were all 0, indicating that the solvent resistance of the shell layer was poor because the thermally expandable microspheres prepared from the shell layer monomers including vinylidene chloride and methyl methacrylate had a low initial expansion temperature, but the thermally expandable microspheres were no longer provided with thermal expansion properties after being immersed in the polar solvent dimethyl carbonate due to the poor resistance of the shell layer.
Further comparing the data of example 1 with examples 5 to 6, it can be seen that too low an amount of conjugated diene added also results in a higher initial foaming temperature of the resulting thermally expandable microspheres and poor solvent resistance.
The applicant states that the present invention has been described with reference to the above examples as a thermally expandable microsphere having a core-shell structure and a method for preparing the same, but the present invention is not limited to the above examples, i.e., it is not meant that the present invention must be practiced by relying on the above examples. It should be apparent to those skilled in the art that any modification of the present invention, equivalent substitution of raw materials for the product of the present invention, addition of auxiliary components, selection of specific modes, etc., falls within the scope of the present invention and the scope of disclosure.

Claims (10)

1. A thermally expandable microsphere having a core-shell structure, wherein the thermally expandable microsphere comprises a core and a shell, the core comprising a blowing agent;
the shell layer comprises a thermoplastic polymer, and the preparation monomer of the thermoplastic polymer comprises conjugated diene monomer.
2. The thermally expandable microsphere according to claim 1, wherein the mass percentage of the shell layer in the thermally expandable microsphere is 70-95%, preferably 70-90%;
the particle diameter of the thermally expandable microspheres is preferably 1 to 500. Mu.m, more preferably 1 to 200. Mu.m, still more preferably 3 to 100. Mu.m, still more preferably 5 to 50. Mu.m.
3. The thermally expanded microspheres according to claim 1 or 2, wherein the blowing agent comprises isobutane;
preferably, the blowing agent further comprises other alkanes having a boiling point not higher than 120 ℃ than isobutane;
preferably, the other alkanes having a boiling point not higher than 120 ℃ comprise any one or a combination of at least two of isopentane, n-pentane, n-hexane, cyclohexane, petroleum ether, n-heptane or isooctane;
preferably, the mass percentage of isobutane in the foaming agent is not less than 20%.
4. A thermally expandable microsphere according to any one of claims 1 to 3, wherein the glass transition temperature of the shell layer is not higher than 120 ℃, preferably 50 to 120 ℃.
5. The thermally expandable microspheres of any one of claims 1-4, wherein the conjugated diene monomer comprises any one or a combination of at least two of 1, 3-butadiene, 1, 3-pentadiene, isoprene, or cyclopentadiene;
preferably, the mass percent of conjugated diene monomer in the preparation monomer of the thermoplastic polymer is more than 10%, more preferably more than 20%;
preferably, the preparation monomers of the thermoplastic polymer further comprise other mono-and/or multi-functional monomers containing carbon-carbon double bonds than the conjugated diene monomer;
preferably, the other monofunctional monomer containing carbon-carbon double bonds comprises any one or a combination of at least two of acrylonitrile monomers, acrylic ester monomers, vinyl pyridine, styrene monomers or vinyl ester monomers;
preferably, the acrylonitrile monomer comprises any one or a combination of at least two of acrylonitrile, methacrylonitrile, fumaronitrile, crotononitrile, alpha-chloroacrylonitrile or alpha-ethoxyacrylonitrile, and further preferably acrylonitrile and/or methacrylonitrile;
preferably, the acrylic monomer comprises any one or a combination of at least two of methyl acrylate, ethyl acrylate, methyl methacrylate, isobornyl methacrylate or ethyl methacrylate;
preferably, the vinyl ester monomer comprises vinyl acetate;
preferably, the styrenic monomer comprises styrene and/or alpha-methylstyrene;
preferably, the other carbon-carbon double bond containing polyfunctional monomers include at least one of divinylbenzene, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1, 4-butanediol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, glycerol di (meth) acrylate, 1, 3-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1, 10-decanediol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol hexa (meth) acrylate, dimethylol tricyclodecane di (meth) acrylate, triallyl formal tri (meth) acrylate, allyl methacrylate, trimethylolpropane tri (meth) acrylate, tributyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 3-acryloxyethylene glycol mono (meth) acrylate, triallyl acrylate or a combination of at least two of the above;
preferably, the mass percentage of the other polyfunctional monomer containing carbon-carbon double bonds in the preparation monomer of the thermoplastic polymer is 0.1 to 1%, and more preferably 0.2 to 0.5%.
6. A method of preparing thermally expandable microspheres according to any one of claims 1-5, comprising the steps of:
(1) Mixing a foaming agent, a preparation monomer of a thermoplastic polymer and an initiator to obtain an oil phase mixture;
(2) And (3) adding the oil phase mixture obtained in the step (1) into an aqueous phase medium for reaction to obtain the thermal expansion microsphere with the core-shell structure.
7. The preparation process according to claim 6, wherein the initiator in step (1) comprises any one or a combination of at least two of an organic peroxide type initiator and/or an azo type initiator, preferably behenyl peroxydicarbonate, di (4-t-butylcyclohexyl) peroxydicarbonate, dioctyl peroxide, dibenzoyl peroxide, dilauroyl peroxide, didecanoyl peroxide, t-butyl peracetate, butyl perborate Gui Xianshu, t-butyl benzoin, t-butyl hydroperoxide, cumene ethyl peroxy, diisopropyl hydroxydicarboxylate, 2' -azobisisoheptonitrile, 2' -azobisisobutyronitrile, 1' -azobis (cyclohexane-1-carbonitrile), dimethyl 2,2' -azobis (2-methylpropionate) or 2,2' -azobis (2-methyl-N- (2-hydroxyethyl) propionamide).
8. The method of claim 6 or 7, wherein the aqueous medium of step (2) comprises a combination of water, a solid suspending agent and a water-soluble salt;
preferably, the solid suspending agent comprises any one or a combination of at least two of silica, chalk, bentonite, starch, methylcellulose, gum agar, hydroxypropyl methylcellulose, carboxymethyl cellulose, colloidal clay, calcium phosphate, calcium carbonate, magnesium hydroxide, barium sulfate, calcium oxalate, aluminum hydroxide, iron hydroxide, zinc hydroxide, nickel hydroxide or manganese hydroxide;
preferably, the water soluble salts include sodium chloride and sodium nitrite;
preferably, the aqueous medium further comprises a stabilizing aid;
preferably, the stabilizing aid comprises any one or a combination of at least two of polyvinylpyrrolidone, sulfonated polystyrene, alginate carboxymethyl fibers, tetramethyl ammonium hydroxide, tetramethyl ammonium chloride, diethanolamine/adipic acid water-soluble condensate, ethylene oxide, urea/formaldehyde water-soluble condensate, polyethylenimine, gelatin, casein, albumin, gelatin proteins, soaps, alkyl sulfates or alkyl sulfonates.
9. The method according to any one of claims 6 to 8, wherein the temperature of the reaction in step (2) is 40 to 80 ℃;
preferably, the reaction time is 5 to 30 hours.
10. The method according to any one of claims 6 to 9, wherein the reaction in step (2) is completed, further comprising the steps of filtering and drying;
preferably, the method of filtration comprises any one or a combination of at least two of bed filtration, positive/negative pressure filtration or spin-on filtration;
preferably, the method of drying comprises any one or a combination of at least two of spray drying, tunnel drying, rotary drying, drum drying, flash drying, palladium drying or fluid bed drying.
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104379647A (en) * 2012-09-04 2015-02-25 西能化工科技(上海)有限公司 Heat-expandable microspheres, preparation method and use thereof
KR20160137820A (en) * 2015-05-22 2016-12-01 인하대학교 산학협력단 Preparation method of thermally expandable microcapsules by Pickering suspension polymerization
CN111684038A (en) * 2018-01-31 2020-09-18 松本油脂制药株式会社 Thermally expandable microspheres and use thereof
CN112661901A (en) * 2020-12-23 2021-04-16 西能化工科技(上海)有限公司 Method for producing thermally expandable microspheres and thermally expandable microspheres
CN115304818A (en) * 2022-08-25 2022-11-08 上海化工研究院有限公司 Ultralow-temperature thermal expansion microsphere prepared based on Pickering emulsion polymerization method and preparation method thereof
CN115304701A (en) * 2022-08-25 2022-11-08 上海化工研究院有限公司 Thermal expansion microsphere prepared based on Pickering emulsion polymerization method and preparation method thereof

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104379647A (en) * 2012-09-04 2015-02-25 西能化工科技(上海)有限公司 Heat-expandable microspheres, preparation method and use thereof
KR20160137820A (en) * 2015-05-22 2016-12-01 인하대학교 산학협력단 Preparation method of thermally expandable microcapsules by Pickering suspension polymerization
CN111684038A (en) * 2018-01-31 2020-09-18 松本油脂制药株式会社 Thermally expandable microspheres and use thereof
CN112661901A (en) * 2020-12-23 2021-04-16 西能化工科技(上海)有限公司 Method for producing thermally expandable microspheres and thermally expandable microspheres
CN115304818A (en) * 2022-08-25 2022-11-08 上海化工研究院有限公司 Ultralow-temperature thermal expansion microsphere prepared based on Pickering emulsion polymerization method and preparation method thereof
CN115304701A (en) * 2022-08-25 2022-11-08 上海化工研究院有限公司 Thermal expansion microsphere prepared based on Pickering emulsion polymerization method and preparation method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
天津大学无机化学教研室: "《大学化学》", vol. 1, 31 August 1994, 天津大学出版社, pages: 11 *

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