Thermal expansion microcapsule with good conductivity and preparation method thereof

Abstract

The invention relates to the technical field of thermal expansion microcapsules, in particular to a thermal expansion microcapsule with good conductivity and a preparation method thereof. The conductive foaming agent is prepared from the following raw materials in parts by weight through polymerization reaction: 100 parts of an olefinic unsaturated monomer, 10-100 parts of a conductive monomer, 0.01-10 parts of a cross-linking agent, 0.01-10 parts of an initiator, 10-60 parts of a foaming agent, 0.01-5 parts of a dispersion stabilizer, 0.01-5 parts of a dispersion stabilizing aid and 0.5-10 parts of inorganic salt. The thermal expansion microcapsule is excellent in conductivity, the foaming performance of the microcapsule is not affected, and the application field of the thermal expansion microcapsule is widened.

Description

Technical Field

[0001] The invention relates to the technical field of thermal expansion microcapsules, and in particular to a thermal expansion microcapsule with good electrical conductivity and a preparation method thereof. Background Art

[0002] Thermally expandable microcapsules have a closed shell and a gas source core material, which can produce an expansion effect. Functionalized thermally expandable microcapsules refer to the grafting of some groups or substances with specific functions onto the surface of thermally expandable microcapsules, or the preparation of functional carbon materials by pyrolysis of thermally expandable microcapsules as precursors. They are new functional materials with unique new functions or great potential for development.

[0003] At present, there are two approaches to the functionalization of thermally expandable microcapsules. The first approach is the pretreatment method, which is to copolymerize monomers containing specific functional groups with original monomers to form functional polymer materials after coating the core material, or to introduce capsule cores with different functions into the reaction system so that they are wrapped in polymer-based shell materials to form functional polymer materials. Common methods for this approach include emulsion polymerization, dispersion polymerization and suspension polymerization. Copolymerization modification is commonly used in pretreatment methods, and the functional groups commonly introduced are double bonds, carboxyl groups, hydroxyl groups, amino groups, acyl chloride groups, etc. However, copolymerization modification has a narrow range of applications due to the complex copolymerization conditions between functional monomers and original monomers, difficulty in control, and high costs.

[0004] The second approach is post-treatment, which means first preparing thermal expansion microcapsules, and then grafting the functional groups or substances to the surface of the microcapsules through chemical reactions. The post-treatment modification is to capture the functional groups or substances through hydrogen bonds, electrostatic bonds, covalent bonds and other forces, and coat them on the surface of thermal expansion microcapsules.

[0005] Conductive thermal expansion microcapsules mainly wrap conductive polymers or inorganic metals on the surface of thermal expansion microcapsules to form conductive medium / thermal expansion microcapsules composite microcapsules. Summary of the invention

[0006] The object of the present invention is to provide a thermally expandable microcapsule with good electrical conductivity and a preparation method thereof, so as to overcome the defects of the prior art.

[0007] In order to solve the above technical problems, the present invention provides a heat-expandable microcapsule with good conductivity, which uses a conductive monomer as a starting material, and is composed of a shell formed of a thermoplastic resin and a foaming agent contained in the shell and vaporized by heating.

[0008] Furthermore, the thermally expandable microcapsule having good electrical conductivity includes an outer shell formed of a thermoplastic resin and a foaming agent contained in the outer shell and vaporized by heating.

[0009] Furthermore, the thermally expandable microcapsules with good electrical conductivity include the following raw materials in parts by weight:

[0010]

[0011]

[0012] Preferably, the following raw materials are included in parts by weight:

[0013]

[0014] Further, the ethylenically unsaturated monomer comprises the following components in weight percentage:

[0015] Acrylic acid monomer 15-80 parts

[0016] 40-90 parts of nitrile monomer

[0017] Acrylate monomer 20-70 parts

[0018] Preferably, the ethylenically unsaturated monomers include the following components in weight percentage:

[0019] Acrylic acid monomer 20-70 parts

[0020] 50-80 parts of nitrile monomer

[0021] Acrylate monomer 30-60 parts

[0022] Further, the acrylic monomer is one or two of methacrylic acid and acrylic acid; the nitrile monomer is one or more of acrylonitrile, methacrylonitrile, 2-methyl-2-acrylonitrile, 2-chloroacrylonitrile, 2-ethoxyacrylonitrile, 2-butenenitrile and trans-1,2-dicyanoethylene; the acrylic ester monomer is one or more of methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, butyl acrylate, n-pentyl acrylate, n-hexyl acrylate, methyl methacrylate, ethyl methacrylate, isobornyl methacrylate, hydroxyethyl acrylate and glycidyl methacrylate.

[0023] Preferably, the acrylic monomer is one or both of methacrylic acid and acrylic acid; the nitrile monomer is one or both of acrylonitrile and methacrylonitrile; and the acrylate monomer is methyl methacrylate.

[0024] Furthermore, the conductive monomer is one or more of a naphthalene monomer, a carbazole monomer and an acridine monomer.

[0025] Furthermore, the naphthalene monomer is one or more of 2-vinylnaphthalene, 2-vinylanthracene, 2-vinylquinone, and 2,6-2 vinylnaphthalene; the carbazole monomer is one or more of 9-phenylcarbazole, 3-methyl-9-phenylcarbazole, 9-(4-methylphenyl)-9H-carbazole, and 9,9'-P-phenylenecarbazole; and the acridine monomer is one or more of 9-phenylacridine, 10-methyl-9-phenylacridine perchlorate, 9-methylacridine, and 2-acridinamine.

[0026] Preferably, the naphthalene monomer is 2-vinylnaphthalene; the carbazole monomer is 9-phenylcarbazole; and the acridine monomer is 9-methylacridine.

[0027] Further, the cross-linking agent is one or more of diisopropylbenzene peroxide, benzoyl peroxide, di-tert-butyl peroxide, diisopropylbenzene hydroperoxide, diethylenetriamine, divinylbenzene, ethylene glycol divinyl ether, divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, ethylene glycol di(meth)acrylate, di(ethylene glycol) di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, triacyl formal, triallyl isocyanate, and triallyl isocyanurate.

[0028] Preferably, the cross-linking agent is one or more of dicumyl peroxide and triethylene glycol divinyl ether.

[0029] Furthermore, the initiator is one or more of azobisisobutyronitrile, dibenzoic acid peroxide, didecanoic acid peroxide, dilauric acid peroxide, peroxydicarbonate, tert-butyl peroxybenzoate, tert-butyl perlaurate, and tert-butyl peracetate.

[0030] Preferably, the initiator is azobisisobutyronitrile.

[0031] Furthermore, the foaming agent is a C4-C8 straight-chain or branched saturated hydrocarbon compound.

[0032] Furthermore, the C4-C8 straight-chain or branched saturated hydrocarbon compound is one or more of n-butane, isobutane, n-pentane, isopentane, n-hexane, n-heptane, n-octane, isooctane and petroleum ether.

[0033] Preferably, the foaming agent is one or more of isooctane, isopentane and petroleum ether.

[0034] Furthermore, the dispersion stabilizer is one or more of calcium phosphate, calcium carbonate, magnesium carbonate, magnesium hydroxide, magnesium oxide, barium sulfate, barium carbonate, barium hydroxide, zinc hydroxide, nickel hydroxide, manganese hydroxide, starch, methyl cellulose, hydroxypropyl methyl cellulose, hydroxymethyl cellulose, colloidal silicon dioxide, aluminum oxide, aluminum hydroxide, iron oxide, and iron hydroxide.

[0035] Preferably, the dispersion stabilizer is one or more of magnesium hydroxide and colloidal silicon dioxide.

[0036] Furthermore, the dispersion stabilization aid is one or more of polyvinyl pyrrolidone, methyl cellulose, polyvinyl alcohol, polyethylene oxide, alkyl trimethyl ammonium chloride, and dialkyl dimethyl ammonium chloride.

[0037] Preferably, the dispersion stabilization aid is polyvinyl pyrrolidone.

[0038] Furthermore, the inorganic salt is one or more of sodium chloride, potassium chloride, sodium sulfate, and potassium sulfate.

[0039] Preferably, the inorganic salt is sodium chloride.

[0040] The specific technical solution of the present invention is as follows: comprising the following steps:

[0041] Step (1): mixing a dispersion stabilizer, a dispersion stabilization aid, a dispersion medium and an inorganic salt to prepare an aqueous phase;

[0042] Step (2): mixing an ethylenically unsaturated monomer, a conductive monomer, a crosslinking agent, an initiator and a foaming agent to prepare an oil phase;

[0043] Step (3): stirring and dispersing the oil phase and the water phase uniformly to obtain a suspension solution;

[0044] Step (4): subjecting the obtained suspension solution to polymerization reaction for 10 to 25 hours in an inert atmosphere (including one or more of nitrogen or argon) at 40 to 90° C. and a pressure of 0.05 to 1 MPa;

[0045] Step (5): After the reaction is completed, the heat-expandable microcapsules are obtained by suction filtration and washing with deionized water. After drying, heat-expandable microcapsules with good electrical conductivity are obtained.

[0046] Preferably, the polymerization reaction temperature is 50-80° C., the pressure is 0.1-0.8 MPa, and the polymerization reaction time is 12-20 hours.

[0047] The inventors have found that by introducing conductive monomers into thermally expandable microcapsules and polymerizing them under certain conditions, thermally expandable microcapsules with good conductivity are finally obtained.

[0048] The beneficial effects of the present invention are:

[0049] The thermal expansion microcapsules of the present invention have excellent electrical conductivity and do not affect the foaming performance of the microcapsules, thereby broadening the application field of the thermal expansion microcapsules. DETAILED DESCRIPTION

[0050] The present invention is further explained below by means of specific examples, but they do not constitute any limitation to the present invention.

[0051] The following methods and instruments were used for the analysis of all heat-expandable microcapsules in the examples:

[0052] The average particle size was measured by Zetasizer Nano.

[0053] The foaming performance of the microcapsules was tested by Mettler TMA841, and the foaming performance of the microcapsules was evaluated using a heating rate of 5°C / min and a load of 0.06N. start is the temperature at which expansion begins, T max is the temperature at which maximum expansion is obtained.

[0054] The resistivity is determined according to the national standard method GB / T 1410-2006.

[0055] Example 1

[0056] Step (1): 3 g of magnesium hydroxide, 2 g of polyvinyl pyrrolidone, 120 g of water and 8 g of sodium chloride are mixed to prepare an aqueous phase;

[0057] Step (2): 100 g of methacrylonitrile, 30 g of 2-vinylnaphthalene, 3 g of diisopropylbenzene peroxide, 1 g of azobisisobutylonitrile and 45 g of isopentane are mixed to prepare an oil phase;

[0058] Step (3): stirring and dispersing the oil phase and the water phase uniformly to obtain a suspension solution;

[0059] Step (4): subjecting the obtained suspension solution to polymerization reaction for 15 hours in an inert atmosphere (here, nitrogen) at 60° C. and a pressure of 0.5 MPa;

[0060] Step (5): After the reaction is completed, the heat-expandable microcapsules are obtained by suction filtration and washing with deionized water, and then dried to obtain heat-expandable microcapsules with good conductivity. The obtained microcapsules are core-shell structures, the outer shell is a thermoplastic polymer, the interior is a low-boiling point foaming agent, and the wall thickness is 2 to 10 microns.

[0061] Example 2

[0062] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 1, 3 g of colloidal silicon dioxide, 2 g of polyvinyl pyrrolidone, 120 g of water and 8 g of sodium chloride were mixed to prepare an aqueous phase.

[0063] Example 3

[0064] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 1, 3 g of magnesium hydroxide, 1 g of polyvinyl pyrrolidone, 120 g of water and 8 g of sodium chloride were mixed to prepare an aqueous phase.

[0065] Example 4

[0066] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 100 g of acrylonitrile, 30 g of 2-vinylnaphthalene, 3 g of diisopropylbenzene peroxide, 1 g of azobisisobutylonitrile and 45 g of isopentane were mixed to prepare an oil phase.

[0067] Example 5

[0068] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 100 g of methacrylonitrile, 30 g of 9-phenylcarbazole, 3 g of diisopropylbenzene peroxide, 1 g of azobisisobutylonitrile and 45 g of isopentane were mixed to prepare an oil phase.

[0069] Example 6

[0070] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 80 g of methacrylonitrile, 30 g of 9-phenylcarbazole, 3 g of diisopropylbenzene peroxide, 1 g of azobisisobutylonitrile and 45 g of isopentane were mixed to prepare an oil phase.

[0071] Example 7

[0072] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 80 g of methacrylonitrile, 30 g of 9-phenylcarbazole, 3 g of triethylene glycol divinyl ether, 1 g of azobisisobutyronitrile and 45 g of isopentane were mixed to prepare an oil phase.

[0073] Example 8

[0074] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 100 g of methacrylonitrile, 30 g of 9-phenylcarbazole, 3 g of dicumyl peroxide, 1 g of azobisisobutyronitrile and 30 g of isooctane were mixed to prepare an oil phase.

[0075] Example 9

[0076] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 100 g of methacrylonitrile, 30 g of 9-phenylcarbazole, 3 g of dicumyl peroxide, 1 g of azobisisobutyronitrile, 25 g of isopentane and 25 g of isooctane were mixed to prepare an oil phase.

[0077] Example 10

[0078] Thermally expandable microcapsules were prepared according to the method of Example 10, except that in step 4, the obtained suspension solution was polymerized in an inert atmosphere at 50° C. and a pressure of 0.5 MPa for 20 hours.

[0079] The above embodiments are partial implementation methods of the present invention, but the implementation methods of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

[0080] Comparative Example 1

[0081] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 1, 2 g of polyvinyl pyrrolidone, 120 g of water and 8 g of sodium chloride were mixed to prepare an aqueous phase.

[0082] Comparative Example 2

[0083] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 1, 3 g of magnesium chloride, 2 g of polyvinyl alcohol, 120 g of water and 8 g of sodium chloride were mixed to prepare an aqueous phase.

[0084] Comparative Example 3

[0085] Heat-expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 100 g of 3-pentenenitrile, 30 g of 2-vinylnaphthalene, 3 g of diisopropylbenzene peroxide, 1 g of azobisisobutyronitrile and 45 g of isopentane were mixed to prepare an oil phase.

[0086] Comparative Example 4

[0087] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 100 g of acrylonitrile, 3 g of diisopropylbenzene peroxide, 1 g of azobisisobutylonitrile and 45 g of isopentane were mixed to prepare an oil phase.

[0088] Comparative Example 5

[0089] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 100 g of methacrylonitrile, 5 g of 9-phenylcarbazole, 3 g of diisopropylbenzene peroxide, 1 g of azobisisobutylonitrile and 45 g of isopentane were mixed to prepare an oil phase.

[0090] Comparative Example 6

[0091] Heat-expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 80 g of methacrylonitrile, 30 g of 9-phenylcarbazole, 1 g of azobisisobutyronitrile and 45 g of isopentane were mixed to prepare an oil phase.

[0092] Comparative Example 7

[0093] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 100 g of methacrylonitrile, 30 g of 9-phenylcarbazole, 3 g of diisopropylbenzene peroxide and 1 g of azobisisobutylonitrile were mixed to prepare an oil phase.

[0094] Comparative Example 8

[0095] Thermally expandable microcapsules were prepared according to the method of Example 1, except that in step 2, 100 g of methacrylonitrile, 30 g of 9-phenylcarbazole, 3 g of diisopropylbenzene peroxide, 1 g of azobisisobutylonitrile and 5 g of isopentane were mixed to prepare an oil phase.

[0096] Comparative Example 9

[0097] Thermally expandable microcapsules were prepared according to the method of Example 10, except that in step 4, the obtained suspension solution was polymerized in an inert atmosphere at 30° C. and a pressure of 2 MPa for 30 hours.

[0098] Comparing the examples and comparative examples, the results are shown in Tables 1 and 2 below:

[0099] Table 1

[0100]

[0101]

[0102] Table 2

[0103]

[0104] Compared with the comparative examples, the examples have better conductivity and excellent foaming performance. Compared with Example 1, Examples 2 and 3 change the type and amount of dispersant, and the conductivity of the obtained heat-expandable microcapsules is slightly reduced; Examples 4 and 5 change the type of monomer, and the resistivity of the obtained microcapsules is slightly reduced; Example 7 changes the type of crosslinking agent, and the foaming performance of the obtained microcapsules is reduced; Examples 8 and 9 change the type and amount of foaming agent, and the pressure of the obtained microcapsules is reduced during foaming, and the foaming ratio is reduced; Example 10 changes the polymerization temperature and time, and can also obtain heat-expandable microcapsules with good conductivity.

[0105] From the comparative examples, comparative example 1 removed the dispersant, comparative example 2 changed the type of dispersant, which was not the optimal dispersant, and was unevenly dispersed during the polymerization process, and the foaming performance and conductivity were reduced; comparative example 3 changed the nitrile monomer, which was not the most preferred monomer, and the obtained microcapsules could not withstand high temperatures and had poor conductivity; comparative example 4 did not add a conductive monomer, and the obtained microcapsules did not have conductivity; comparative example 5 reduced the amount of conductive monomer, which was not the optimal ratio, and the conductivity of the obtained microcapsules was reduced; comparative example 6 did not add a cross-linking agent, resulting in a low cross-linking degree of the microcapsule shell, poor rigidity, and poor foaming performance; comparative example 7 did not add a foaming agent, and comparative example 8 reduced the amount of foaming agent, which was not the optimal ratio, and the obtained microcapsules had very poor foaming performance; comparative example 9 changed the polymerization temperature and time, which were not the optimal temperature and time, resulting in a low microcapsule molding rate, poor foaming performance and conductivity.

[0106] The heat-expandable microcapsules with good electrical conductivity of the present invention can be used for filling antistatic composite materials. Foaming materials are widely used in the fields of automobile interior and packaging, but they are prone to generate static electricity hazards during use. Research and preparation of foaming materials with antistatic properties can avoid such situations. The heat-expandable microcapsules with good electrical conductivity prepared in Example 1 were heated at 210°C for 5 minutes for foaming, and then used as conductive fillers to fill the antistatic composite material biaxially stretched polypropylene. The resistivity was measured according to the national standard GB / T 1410-2006 and was 0.25Ω·m.

Claims

1. A thermally expandable microcapsule having good electrical conductivity, characterized in that: It is a thermal expansion microcapsule made from conductive monomers as starting materials; It is prepared by polymerization reaction of the following raw materials in parts by weight:

2. The thermally expandable microcapsule having good electrical conductivity according to claim 1, characterized in that: The ethylenically unsaturated monomers include the following components in percentage by weight: Acrylic acid monomer 15-80 parts 40-90 parts of nitrile monomer Acrylate monomer 20-70 parts The acrylic monomer is one or both of methacrylic acid and acrylic acid; The nitrile monomer is one or more of acrylonitrile, methacrylonitrile, 2-methyl-2-acrylonitrile, 2-chloroacrylonitrile, 2-ethoxyacrylonitrile, 2-butenenitrile and trans-1,2-dicyanoethylene; The acrylic acid ester monomer is one or more of methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, butyl acrylate, n-pentyl acrylate, n-hexyl acrylate, methyl methacrylate, ethyl methacrylate, isobornyl methacrylate, hydroxyethyl acrylate and glycidyl methacrylate.

3. The thermally expandable microcapsule having good electrical conductivity according to claim 1, characterized in that: The conductive monomer is one or more of a naphthalene monomer, a carbazole monomer and an acridine monomer; The naphthalene monomer is one or more of 2-vinylnaphthalene, 2-vinylanthracene, 2-vinylquinone, and 2,6-2 vinylnaphthalene; The carbazole monomer is one or more of 9-phenylcarbazole, 3-methyl-9-phenylcarbazole, 9-(4-methylphenyl)-9H-carbazole, and 9,9'-P-phenylenecarbazole; The acridine monomer is one or more of 9-phenylacridine, 10-methyl-9-phenylacridine perchlorate, 9-methylacridine, and 2-acridineamine.

4. The thermally expandable microcapsule having good electrical conductivity according to claim 1, characterized in that: The cross-linking agent is one or more of diisopropylbenzene peroxide, benzoyl peroxide, di-tert-butyl peroxide, diisopropylbenzene hydroperoxide, diethylenetriamine, divinylbenzene, ethylene glycol divinyl ether, divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, ethylene glycol di(meth)acrylate, di(ethylene glycol) di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, triacyl formal, triallyl isocyanate, and triallyl isocyanurate; The initiator is one or more of azobisisobutyronitrile, dibenzoic acid peroxide, didecanoic acid peroxide, dilauric acid peroxide, peroxydicarbonate, tert-butyl peroxybenzoate, tert-butyl perlaurate, and tert-butyl peracetate.

5. The thermally expandable microcapsule having good electrical conductivity according to claim 1, characterized in that: The foaming agent is a C4-C8 straight-chain or branched saturated hydrocarbon compound; The C4-C8 straight-chain or branched saturated hydrocarbon compound is preferably one or more of n-butane, isobutane, n-pentane, isopentane, n-hexane, n-heptane, n-octane, isooctane and petroleum ether.

6. The thermally expandable microcapsule having good electrical conductivity according to claim 1, characterized in that: The dispersion stabilizer is one or more of calcium phosphate, calcium carbonate, magnesium carbonate, magnesium hydroxide, magnesium oxide, barium sulfate, barium carbonate, barium hydroxide, zinc hydroxide, nickel hydroxide, manganese hydroxide, starch, methyl cellulose, hydroxypropyl methyl cellulose, hydroxymethyl cellulose, colloidal silicon dioxide, aluminum oxide, aluminum hydroxide, iron oxide, and iron hydroxide; The dispersion stabilization aid is one or more of polyvinyl pyrrolidone, methyl cellulose, polyvinyl alcohol, polyethylene oxide, alkyl trimethyl ammonium chloride, and dialkyl dimethyl ammonium chloride; The inorganic salt is one or more of sodium chloride, potassium chloride, sodium sulfate and potassium sulfate.

7. The thermally expandable microcapsule with good conductivity according to any one of claims 1 to 6, characterized in that: The heat-expandable microspheres are composed of a shell formed of a thermoplastic resin and a foaming agent contained in the shell and vaporized by heating.

8. A method for preparing the thermally expandable microcapsules with good electrical conductivity according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step (1): mixing a dispersion stabilizer, a dispersion stabilizing aid, a dispersion medium and an inorganic salt to prepare an aqueous phase; Step (2): mixing an ethylenically unsaturated monomer, a conductive monomer, a crosslinking agent, an initiator and a foaming agent to prepare an oil phase; Step (3): stirring and dispersing the oil phase and the water phase uniformly to obtain a suspension solution; Step (4): subjecting the obtained suspension solution to polymerization reaction for 10 to 25 hours in an inert atmosphere at 40 to 90° C. and a pressure of 0.05 to 1 MPa; Step (5): After the reaction is completed, the heat-expandable microcapsules are obtained by suction filtration and washing with deionized water. After drying, heat-expandable microcapsules with good electrical conductivity are obtained.

9. The method for preparing heat-expandable microcapsules with good electrical conductivity according to claim 8, characterized in that: The dispersion medium is water.

10. Use of the thermally expandable microcapsules with good electrical conductivity as claimed in any one of claims 1 to 7, characterized in that: It can be used for filling antistatic composite materials, and the temperature range of thermal expansion is 120-230℃.

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