JPH05120913A - Electrically responsive soft plastic body or electrically responsive gel - Google Patents

Abstract

PURPOSE:To provide functional gel and a soft plastic body whose viscoelasticity can be extensively changed by applying an electric field. CONSTITUTION:At least one kind or more of fine powder bodies, whose mean particle diameter is 0.5-5.00mum, being selected from B-(1) the fine powder body, whose conductivity, under a dispersed state in a matrix phase, is one tenth or less of the conductivity of the matrix phase, (2) the fine powder body, whose conductivity, under the dispersed state in the matrix phase, is ten times or more of the conductivity of the matrix phase, and (3) the fine powder body being composed of two dimensional layer-like complex particles are dispersed in electrically insulating high polymer material, being selected from A-(1) a high polymer, whose viscosity is 10<4> centistokes or more, and (2) partially crosslinked high polymer gel-like medium, whose penetration is 40 or more at a room temperature, so as to produce an electrically responsive soft plastic body or electrically responsive gel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrically responsive soft-plastic material or an electrically responsive gel whose viscoelastic properties are changed by the application of an electric field, and for example, energy absorption and protection of dampers, shock absorbers, engine mounts, etc. The present invention relates to an electrically responsive soft-plastic body and an electrically responsive gel applied to general industrial parts, automobile parts, etc. for vibration purposes.

[0002]

2. Description of the Related Art Conventionally, an anti-vibration rubber or a damper filled with an electrorheological fluid has been practically used as a device having an excellent function of adjusting a spring characteristic and a loss characteristic by changing an electric field applied according to an input. Is being considered.

However, in order to put into practical use the anti-vibration rubber and the damper to which the electrorheological fluid is applied, it is necessary to completely seal the electrorheological fluid and the dispersed fine particles do not settle and condense for a long period of time. A highly stable electrorheological fluid is required, but it is not easy to satisfy this requirement due to the difference in specific gravity between the insulating oil, which is the medium of the electrorheological fluid, and the dispersed fine particles, and therefore the practical application of the above device is not possible. We are in a difficult situation.

An electric field-flexible polymer gel is known as a material whose viscoelastic property can be changed by applying an electric field. However, this electric-field bendable polymer gel only acts in a special solvent. Uses are limited.

Recently, a material having a variable elastic modulus by an electric field has been reported (JP-A-3-91541). This elastic modulus variable material is a material in which fine powder that is electrically polarized by the action of an electric field is dispersed in an electrically insulating polymer material. The dispersed fine particles used in this material are hydrophilic and are polarized by the action of water. Particles, conductive polymer particles, or particles whose electric polarization is not sufficiently large due to the action of an electric field. These are all difficult to control the water content during the production of the elastic modulus variable material, and have a large temperature dependence and high quality. The material is lacking in stability, is a material through which an excessive current flows when an electric field is applied, or is a material that does not provide a sufficient effect of varying the elastic modulus. It is a thing.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to improve the above circumstances, and uses a highly fluid liquid medium such as an oil in an electrorheological fluid or a solvent in an electric field bending polymer gel. First, it provides an electrically responsive soft-plastic body and an electrically responsive gel in which fine powders that are electrically polarized by the action of an electric field are dispersed in an electrically insulating polymer material, and in particular, the viscoelastic properties change significantly when an electric field is applied. It is an object of the present invention to provide a stable electro-responsive soft plastic body or electro-responsive gel having high practicality.

[0007]

Means and Actions for Solving the Problems The present inventors have
As a result of intensive studies to achieve the above-mentioned object, an electrically responsive soft-plastic body or an electrically responsive gel, in which fine powder that is electrically polarized by the action of an electric field is dispersed in an electrically insulating polymer material, A. A polymer having a viscosity of 10 ⁴ centistokes or more An electrically insulating polymer material selected from a partially cross-linked polymer gel medium having a penetration of 40 or more at room temperature B. The matrix phase is composed of fine particles non-uniformly dispersed type composite particles dispersed in a state in which a large amount of fine particles are present near the surface and a small amount on the center side or a state in which a small amount is present near the surface and a large amount on the center side. Fine powder having a conductivity of 1/10 or less, or fine particle uniform dispersion type composite particles in which fine particles are uniformly dispersed in a matrix phase, and the electric conductivity of the dispersed fine particles is 1/10 or less of the electric conductivity of the matrix phase. A fine powder comprising fine particle-dispersed composite particles in which fine particles are dispersed in a matrix phase, and the electric conductivity of the dispersed fine particles is 10 times or more the electric conductivity of the matrix phase. By dispersing at least one kind of fine powder having an average particle diameter of 0.5 to 500 μm. And it found that it is possible to obtain a functional material not conventionally viscoelastic characteristics are changed greatly by the application of, and have completed the present invention.

The present invention will be described in more detail below. The electrically responsive soft-plastic material or electrically responsive gel of the present invention comprises an electrically insulating polymer material and a fine powder which is electrically polarized by the action of an electric field dispersed therein. It is a thing.

Here, the electrically insulating polymer material used in the present invention is preferably a material having appropriate fluidity or flexibility at room temperature or operating temperature, and is a polymer or partially crosslinked polymer. It is a gel medium.

That is, the high molecular weight polymer used in the electrically insulating high molecular weight material of the present invention is a viscous substance having a viscosity of 10 ⁴ centistokes or more. For example, a silicone type polymer, a hydrocarbon type polymer, a halogenated hydrocarbon type polymer. Examples thereof include polymers, phosphazene polymers, and various viscous materials obtained by adding a solvent or the like to them.

The partially cross-linked polymer gel medium used in the electrically insulating polymer material of the present invention has a penetration at room temperature of 40 (JIS K2220) or more, preferably 60.
The above-mentioned partially cross-linked polymer gels include, for example, polymer gels obtained by partially cross-linking the materials exemplified as the above-mentioned polymer.

On the other hand, the fine powder used in the present invention is obtained by impregnating organic particles having a high residual carbon rate with a metal compound,
Fine particles that are obtained by a method such as carbonization and have a large number of fine particles in the vicinity of the surface of the matrix phase and a small amount in the central side are dispersed as heterogeneous particles, or a compound that forms an oxide at high temperature is used as the core. Fine particles obtained by making particles coated with an organic resin with a high residual carbon rate such as phenol resin and carbonizing these particles. Fine particles dispersed in a state in which there are few fine particles near the surface of the matrix phase and many in the center side. Consisting of heterogeneous dispersion type composite particles,
The electric conductivity of the matrix phase is preferably 10 ⁻¹⁰
-10 ² Scm ^-1 , the dispersed fine particles are formed of at least one material selected from semiconductors and insulators, and 1/10 of the electrical conductivity of the matrix phase.
Fine powder which is the following, consisting of fine particles uniformly dispersed composite particles obtained by a method such as mixing and powdering organic particles having a high residual carbon rate and a metal compound and then carbonizing, and the electrical conductivity of the matrix phase is preferably Fine powder having a particle size of 10 ⁻¹⁰ to 10 ² Scm ⁻¹ , wherein the dispersed fine particles are formed of at least one kind of material selected from semiconductors and insulators, and are 1/10 or less of the electric conductivity of the matrix phase. , A fine particle-dispersed composite particle obtained by mixing and powdering organic particles having a high residual carbon rate and a metal compound, and then carbonizing the mixture, wherein the matrix phase is at least one kind of material selected from a semiconductor and an insulator. And the electric conductivity of the dispersed fine particles is preferably 10 ^−10.
Fine powder having a particle size of 10 ² Scm ⁻¹ and 10 times or more the electric conductivity of the matrix phase, fine powder composed of fine particles in which carbon is compounded between layers of a layered clay mineral having a two-dimensional layered structure, for example, It is selected from fine powders obtained by inserting an organic compound having a high residual carbon ratio between layers of a substance having a two-dimensional layered structure such as a layered aluminosilicate or a layered polysilicate, and then carbonizing.

The fine powders (1) to (3) will be described in more detail. In the fine powder of fine particle heterogeneous dispersion type composite particles having a lower electric conductivity than the B-matrix, the matrix phase has a medium conductivity. , Preferably 1
0 ^-10 to 10 ² Scm ^-1 , more preferably 10 ^-10
It is about 10 ⁰ Scm ^-1 . As a material for forming the matrix phase, an organic material or an inorganic material can be used as long as it exhibits the electric conductivity. Specific examples include carbonaceous materials, carbide materials such as boron carbide and aluminum carbide, organic semiconductor materials such as polyaniline and polyacenequinone, and oxide semiconductor materials such as zinc oxide, potassium titanate and barium titanate. However, carbonaceous materials are preferred. Among them, a carbonaceous material having a carbon content of 80 to 99.9% is preferable, and a more preferable carbonaceous material is 90 to 99%. The balance is usually composed of hydrogen atoms, oxygen atoms and nitrogen atoms.

On the other hand, the fine particles dispersed in the matrix phase are at least one material selected from semiconductors and insulators, but it is essential that the electrical conductivity of the fine particles is lower than that of the matrix phase. 1/10 or less of that of the matrix phase, preferably 1/10
1/10 ¹⁴ , more preferably 1/10 ³ to 1/10 ¹⁴
Is. If it is larger than 1/10, effective composite particles cannot be obtained. Further, the electric conductivity of the fine particles satisfies the above conditions and is 10 ^-2 Scm ^-1 or less, particularly 10 ^-6 Scm ^-1.
The following is preferable.

Examples of the fine particle material include oxides such as alumina, silica, boron oxide, titania, calcium oxide, iron oxide, tin oxide and zinc oxide, and non-oxides such as silicon carbide, silicon nitride and aluminum nitride. Can be mentioned. Of these, preferred are silica, alumina, titania and the like.

The size of the fine particles is preferably 1 nm.
The range of ˜1 μm, more preferably 2 nm to 0.5 μm is suitable. The total amount of fine particles dispersed in the composite particles is preferably 0.01 to 40%, more preferably 0.1.
1 to 30%. If it is less than 0.01%, the effect of the present invention cannot be obtained, and if it is more than 40%, there may be a problem in producing composite particles. When the composite particles of the present invention are formed such that the fine particle dispersion amount is large on the surface side and small on the center side, the dispersion amount on the surface side is 0.1 to 99%, particularly 1
~ 95%, the amount of dispersion near the center is 0 to 30%, especially 0 to 2
It is preferable that the amount of dispersion on the surface side is 1.5% or more, and particularly about 3 times or more of the amount of dispersion near the center. Further, when the amount of fine particles dispersed is small on the surface side and large on the center side, it is preferable to set the dispersed amount to the reverse of the above.

Here, as a method for producing the B-composite particles, the following methods (A) to (D) can be mentioned in the case of composite particles in which a large amount of fine particles are dispersed on the surface side of the matrix phase. .. (A) Thermosetting resin such as phenol resin, furan resin, polydimethylsilane resin, melamine resin, and epoxy resin, or organic particles such as resin obtained by subjecting thermoplastic resin such as polyacrylonitrile to radiation treatment or infusibilization Metal alkoxides such as silicates, aluminum isopropoxide, and titanium isopropoxide; organometallic complexes such as ferrocene; organic compounds such as borate esters synthesized from diethanolamine and boric acid; Then, a method of carbonizing. (B) After attaching a compound such as a metal alkoxide, an organometallic complex, or an ester of an organic compound and an inorganic acid to the surface of an organic particle having a high residual carbon rate such as a phenol resin, a furan resin, or a polydimethylsilane resin, A method of carbonizing fine particles coated with a liquid organic compound having a high residual coal rate by heat treatment. (C) High residual carbon content on the surface of organic particles having a high residual carbon content such as phenol resin, furan resin, and polydimethylsilane resin on compounds such as metal alkoxides, organometallic complexes, and esters of organic compounds with inorganic acids. A method in which a mixture of liquid organic compounds is applied and then carbonized by heat treatment. (D) After heat-treating organic particles having a high residual carbon rate such as phenol resin, furan resin, and polydimethylsilane resin,
After depositing a compound for forming desired electrically conductive fine particles on the surface by a method such as chemical vapor deposition (CVD),
Further, a method of carbonizing by heat treatment.

In the case of composite particles in which a large amount of fine particles are dispersed on the center side of the matrix phase, the method (E) below can be used. (E) A compound having a small solubility in water at a low temperature, a large solubility at a high temperature, and a compound capable of forming an oxide at a high temperature as a core, and coated with a phenol resin to form particles. The particles are impregnated with water by a method such as immersing the particles in warm water, and after completion of the impregnation, the phenol resin particles having the above compound as a core are carbonized.

For example, spherical phenol resin particles having boric acid as a nucleus are prepared by granulating and curing a resol-type phenol resin in a solution containing boric acid and preferably a surfactant as a dispersant, and the spherical phenol resin particles are treated with warm water. After soaking in water for 24 hours, remove from water and dry. Then, carbonization is performed in a non-oxidizing atmosphere. The particles thus obtained are heterogeneous dispersion type composite particles in which the conductive medium carbonaceous material is dispersed in the matrix phase, and the conductive low-rank boron oxide fine particles are dispersed in a large amount in the center side and a small amount in the surface side. ..

In the fine powder of B-fine particle uniform dispersion type composite particles, the electric conductivity of the matrix phase is medium conductivity, preferably 10 ^-10 to 10 ² Scm ^-1 ,
More preferably 10 ^-10 ~10 ⁰ Scm ^-1. As a material for forming the matrix phase, an organic material or an inorganic material can be used as long as it exhibits the electric conductivity. Specific examples include carbonaceous materials, carbide materials such as boron carbide and aluminum carbide, organic semiconductor materials such as polyaniline and polyacenequinone, and oxide semiconductor materials such as zinc oxide, potassium titanate and barium titanate. However, carbonaceous materials are preferred. Above all, the carbon content is 80 to 9
9.9% carbonaceous material is preferred and more preferred is 90-99% carbonaceous material. The balance is usually composed of hydrogen atoms, oxygen atoms and nitrogen atoms.

On the other hand, the fine particles dispersed in the matrix phase are at least one material selected from semiconductors and insulators, but it is essential that the electrical conductivity of the fine particles is lower than that of the matrix phase. 1/10 or less of that of the matrix phase, preferably 1/10 to 1/1
It is 0 ¹⁴ , more preferably 1/10 ³ to 1/10 ¹⁴ . If it is larger than 1/10, effective composite particles cannot be obtained. Further, the electrical conductivity of the fine particles is preferably 10 ^-2 Scm ^-1 or less, particularly preferably 10 ^-6 Scm ^-1 or less while satisfying the above conditions.

Examples of the fine particle material include oxides such as alumina, silica, boron oxide, titania, calcium oxide, iron oxide, tin oxide and zinc oxide, and non-oxides such as silicon carbide, silicon nitride and aluminum nitride. Can be mentioned. Further, when the matrix phase is made of a carbonaceous material, it is possible to use a carbonaceous material having a conductivity lower than that of the carbonaceous material as fine particles. Among the fine particle materials, silica, alumina, titania and the like are preferable.

The size of the fine particles is preferably 1 nm.
The range of 10 to 10 μm, more preferably 2 nm to 5 μm is suitable. The total amount of fine particles dispersed in the composite particles is preferably 0.1 to 70%, more preferably 1 to 60%.
%. When it is less than 0.1%, the electrical properties of the composite particles are not controlled in electrical conductivity, and are almost the same as those of the conductive intermediate matrix phase, and the effect of the present invention cannot be obtained. On the other hand, if it is more than 70%, the electrical characteristics of the composite particles will be similar to those of conductive low-grade particles, which is not preferable.

Here, as a method for producing the powder of B-composite particles, a starting compound corresponding to a conductive intermediate matrix phase (hereinafter abbreviated as a matrix phase compound) and a conductive low level fine particle are used. A starting compound (hereinafter, abbreviated as fine particle compound) to be mixed, a method of granulating the mixture by a method such as spray drying, a method of granulating using a ball mill after solidifying the mixture by a curing reaction, A method of heat-treating the granulated powder at a higher temperature,
Alternatively, a method in which the mixture is heat-treated once and then granulated can be used. In order to produce the desired powder, a combination of starting compounds, a method for mixing the starting compounds,
In a manufacturing process such as a granulation method or a heat treatment method (including a heat treatment means and a heat treatment atmosphere), depending on physical characteristics such as morphology and thermal characteristics of both compounds, the following special cases (F) to (H) are used. The method can be adopted. (F) The matrix phase compound is in a liquid state or a solution state and contains the fine particle compound, or liquefies in the production process to contain the fine particle compound, and then gels by an appropriate method. Alternatively, a method of curing and heat treatment. As the fine particle compound, a solid material is selected in the manufacturing process. (G) When both the matrix phase compound and the fine particle compound are mixed in a liquid or solution form to produce a powder, the fine particle compound forms a gel or a precipitate faster than the matrix phase compound. A method in which the compound is selected, the amount ratio of the both compounds is further selected, and the both compounds are mixed, then gelled or cured, granulated, and heat-treated. (H) When both the matrix phase compound and the fine particle compound are mixed in a solid state to produce a powder, the matrix phase compound is fluidized during the production process for obtaining the target powder. And that the fine particle compound is in a solid state in all the production processes, both compounds are mixed, a heat treatment is performed if necessary, and then granulated.

According to the above manufacturing methods (F) to (H), B-
However, depending on the combination of the starting compounds, it is desirable to heat the obtained powder at a higher temperature and change the conductivity of the powder by controlling the heat treatment temperature and the heat treatment atmosphere. As an example of controlling the heat treatment atmosphere, when it is desired to leave a large amount of carbide in the composite particles even after the heat treatment, an inert gas atmosphere is usually selected, but particularly when it is desired to generate a nitride inside the composite particles, An atmosphere such as NH ₃ gas or N ₂ gas is selected.

As the starting compound corresponding to the matrix phase, at least one compound selected from organic compounds having a high residual carbon rate such as phenol resin, furan resin and polydimethylsilane resin can be used.

On the other hand, the starting compounds corresponding to the fine particles include metal alkoxides such as ethyl silicate, aluminum isopropoxide and titanium isopropoxide, organic metal complexes such as ferrocene, organic compounds such as borate ester synthesized from diethanolamine and boric acid. At least one compound selected from an ester consisting of a compound and an inorganic acid, silica, alumina, titania, other insulating materials, semiconductor materials and the like can be used.

Even when the above-mentioned organic compound having a high residual carbon rate and an organic compound such as tar or pitch which produces a carbon material having higher conductivity after carbonization treatment are combined, the former compound corresponds to fine particles. It is possible to obtain a B-powder composed of composite particles in which the latter compound corresponds to the matrix phase.

Further, in the fine particle non-uniform dispersion type composite particles having a higher electric conductivity than the B-matrix, the fine particles are dispersed in the matrix phase in such a manner that the fine particles are uniformly dispersed in the matrix phase. Alternatively, it may be a heterogeneous dispersion type composite particle in which a large amount of fine particles are present on the surface side of the matrix and a small amount on the center side, or a state in which fine particles are small on the surface side of the matrix and a large amount of fine particles are present on the center side.

Here, the electrical conductivity of the matrix phase is at least one material selected from semiconductors and insulators having low conductivity, and the electrical conductivity is 10 ^-2.
Scm ^-1 or less, more preferably 10 ^-6 Scm ^-1 or less. Examples of the material for forming the matrix phase include oxides such as alumina, silica, boron oxide, titania, calcium oxide, iron oxide, tin oxide and zinc oxide, and non-oxidizing materials such as silicon carbide, silicon nitride and aluminum nitride. The thing etc. can be mentioned. Of these, preferred are silica, alumina, titania and the like.

On the other hand, the fine particles dispersed in this matrix phase
The electrical conductivity of the particles is higher for the matrix phase
Is essential, having one of that of the matrix phase
0 times or more, preferably 10 -10¹⁴Double, more preferably
10³-10¹⁴Is. Effective if this is less than 10 times
Complex particles cannot be obtained. Furthermore, the electrical conductivity of the fine particles
Has a medium conductivity, preferably 10 while satisfying the above conditions.
^-Ten-10²Scm^-1And more preferably 10^-Ten~
10⁰Scm^-1It is necessary to

As the fine particle material, any organic material or inorganic material can be used as long as it exhibits the electric conductivity. Specifically, carbonaceous materials, boron carbide,
Examples thereof include carbide materials such as aluminum carbide, organic semiconductor materials such as polyaniline and polyacenequinone, and oxide semiconductor materials such as zinc oxide, potassium titanate, and barium titanate. Among them, carbonaceous materials are preferable. is there. Among them, the carbon content rate is 80 to 99.9%
The carbonaceous material of No.
It is 99% carbonaceous material. The balance is usually formed of hydrogen atoms, oxygen atoms and nitrogen atoms. When these carbonaceous materials are used as the fine particle material, it is possible to use a carbonaceous material having a lower conductivity than that of the carbonaceous material as the matrix phase.

The size of the fine particles is preferably 1 nm.
The range of ˜1 μm, more preferably 2 nm to 0.5 μm is suitable. The total amount of fine particles dispersed in the composite particles is 15 to 99.5%, preferably 30 to 90%. When it is less than 15%, the electrical properties of the composite particles of the present invention are not controlled in electrical conductivity, and are almost the same as those of the matrix phase of low conductivity, and the effect of the present invention cannot be obtained.
If it is more than 99.5%, the electrical properties of the composite particles will be similar to those of conductive intermediate particles, which is not preferable.

When the fine particles are non-uniformly dispersed, when the fine particles are large on the surface side and small on the center side, the amount of dispersion on the surface side is 0.1 to 99%, particularly 1 to 95%, and the amount near the center is small. The dispersion amount is 0 to 30%, particularly 0 to 25%, and the dispersion amount on the surface side is 1.5 times or more the dispersion amount near the center, particularly 3
It is preferably about double or more. Further, when the amount of fine particles dispersed is small on the surface side and large on the center side, it is preferable to set the dispersed amount to the reverse of the above.

Here, as a method for producing the powder of B-composite particles, a starting compound corresponding to a matrix phase having a low conductivity (hereinafter abbreviated as matrix phase compound) and fine particles having a conductive middle level are used. A starting compound (hereinafter, abbreviated as a fine particle compound) to be mixed, and the mixture is granulated by a method such as spray drying, or the mixture is solidified by a curing reaction or the like and then granulated using a ball mill or the like. Examples thereof include a method of heat-treating the granulated powder at a higher temperature, and a method of heat-treating the mixture once and then granulating. In order to produce the desired powder, in the production process such as a combination of starting compounds, a mixing method thereof, a granulation method, or a heat treatment method (including a heat treatment means and a heat treatment atmosphere), the form of both compounds is Depending on physical characteristics such as thermal characteristics, the following special methods (I) to (K) can be adopted. (I) The matrix phase compound is in a liquid state or a solution state and contains the fine particle compound, or is liquefied in the production process to contain the fine particle compound, and then gelated by an appropriate method. Alternatively, a method of curing and heat treatment. As the fine particle compound, a solid material is selected in the manufacturing process. (J) When both the matrix phase compound and the fine particle compound are mixed in a liquid or solution form to produce a powder, the fine particle compound forms a gel or a precipitate faster than the matrix phase compound. A method in which the compound is selected, the amount ratio of the both compounds is further selected, and the both compounds are mixed, then gelled or cured, granulated, and heat-treated. (K) When both the matrix phase compound and the fine particle compound are mixed in a solid state to produce a powder, the matrix phase compound is fluid during the production process for obtaining the desired powder. And that the fine particle compound is in a solid state in all the production processes, both compounds are mixed, a heat treatment is performed if necessary, and then granulated.

According to the above-mentioned production methods (I) to (K), B-
It is desirable to heat the obtained powder at a higher temperature depending on the combination of the starting compounds and change the conductivity of the powder by controlling the heat treatment temperature and the heat treatment atmosphere. As an example of controlling the heat treatment atmosphere, when it is desired to leave a large amount of carbide in the composite particles even after the heat treatment, an inert gas atmosphere is usually selected, but particularly when it is desired to generate a nitride inside the composite particles, An atmosphere such as NH ₃ gas or N ₂ gas is selected.

Examples of the starting compound corresponding to the matrix phase include metal alkoxides such as ethyl silicate, aluminum isopropoxide and titanium isopropoxide, organic metal complexes such as ferrocene, organic compounds such as boric acid ester synthesized from diethanolamine and boric acid. It is possible to use at least one compound selected from liquid compounds such as esters of compounds and inorganic acids or soluble compounds.

On the other hand, as the starting compound corresponding to the fine particles, at least one compound selected from organic compounds having a high residual carbon rate such as phenol resin, furan resin and polydimethylsilane resin can be used.

It should be noted that the above-mentioned organic compound having a high residual carbon rate is combined with a carbide material having higher conductivity such as boron carbide or aluminum carbide, an organic semiconductor material such as polyaniline or polyacenequinone, or an organic compound such as tar or pitch. Even in the case, B-powder composed of composite particles in which the former compound corresponds to the matrix phase and the latter compound corresponds to fine particles can be obtained.

When an electrically responsive soft plastic material or gel is obtained using the above-mentioned fine powder, the electric conductivity of the fine powder is not particularly limited, but the electric conductivity measured by molding the powder is preferably 10 ^{−. It is 13} to 10 ² Scm ^-1 , and more preferably 10 ^-12 to 10 ^-2 Scm ^-1 . The water content of the fine powder is preferably 1% or less, more preferably 0.5% or less.

The average particle size of the fine powder is 0.5 to 500.
μm, and preferably 1 to 200 μm. If the average particle size of the fine powder particles exceeds 500 μm, it is difficult to disperse the particles uniformly in the medium, and if it is less than 0.5 μm, the change in viscoelasticity due to the application of an electric field becomes small, which is not preferable.

The mixing ratio of the dispersed fine particles to 100 parts by weight of the electrically insulating polymer material of the present invention is preferably 20 to 3.
The amount is 00 parts by weight, more preferably 30 to 200 parts by weight. If the blending ratio of the dispersed fine particles is less than 20 parts by weight, the change in viscoelastic properties due to the application of an electric field is small, and
If it exceeds the weight part, it may be difficult to disperse the powder in the medium.

The thus obtained electro-responsive soft plastic material or electro-responsive gel has stable characteristics which can greatly change viscoelastic characteristics such as elastic modulus and loss cutoff (tan δ) by applying an electric field. Is a functional material.

Normally, when a vibration system including a vibration isolation device receives an input corresponding to its natural frequency, the vibration system vibrates greatly due to the resonance effect of the system. Therefore, how to reduce this resonance effect is a major issue in the design of the vibration isolation device, but this problem can be easily solved by using the material of the present invention whose viscoelastic characteristics are greatly changed by voltage application. For example, the natural frequency can be moved by utilizing a large change in the elastic modulus due to the application of a voltage, and resonance with respect to the input can be prevented. Further, the magnitude of the resonance effect can be controlled by utilizing the change in tan δ.

[0045]

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples. The present invention is not limited to the examples below.

[Example 1] One-component thermosetting silicone gel manufactured by Toshiba Silicone Co., Ltd. (TSE3051: penetration 85)
An average of 100 parts by weight of finely divided heterogeneous dispersion type composite particles in which silica fine particles obtained by impregnating phenol resin particles with ethyl silicate and then carbonizing are dispersed in a large amount near the surface of the matrix phase and in a small amount on the center side. Disperse 100 parts by weight of fine powder having a particle size of 170 μm, and
An electro-responsive gel material was prepared by heat treatment at 50 ° C. for 2 hours. A voltage of 2 kV / mm was applied to this material, and a change in viscoelasticity was measured using an RDS-II type viscoelasticity measuring device manufactured by Rheometrics. As a result, the storage elastic modulus (G ′) was 7 as compared with that under no electric field. Doubled.

Example 2 One-component thermosetting silicone gel manufactured by Toshiba Silicone Co., Ltd. (TSE3051: Penetration 85)
100 parts by weight of 100 parts by weight of fine powder having an average particle size of 20 μm composed of fine particle non-uniform dispersion type composite particles prepared by the same method as in Example 1 was dispersed, and heat treated at 150 ° C. for 2 hours to obtain electrical responsiveness. A gel material was created. When a voltage of 2 kV / mm was applied to this material at room temperature and a change in viscoelasticity was measured in the same manner as in Example 1, G ′ was increased 32 times.

[Example 3] One-component thermosetting silicone gel manufactured by Toshiba Silicone Co., Ltd. (TSE3051: penetration 85)
An average particle size of 25 was obtained by inserting acrylonitrile between 100 parts by weight of montmorillonite, which is a clay mineral having a two-dimensional layered structure, polymerizing, and then carbonizing.
An electrically responsive gel material was prepared by dispersing 150 parts by weight of fine powder composed of carbon composite fine particles having a size of μm and heat-treating at 150 ° C. for 2 hours. 2 kV at room temperature for this material
When a change in viscoelasticity was measured in the same manner as in Example 1 by applying a voltage of / mm, G ′ increased 18 times.

[Comparative Example 1] One-component thermosetting silicone gel manufactured by Toshiba Silicone Co., Ltd. (TSE3051: penetration 85)
To 100 parts by weight, 100 parts by weight of fine powder obtained by pulverizing ion exchange resin (Diaion) manufactured by Mitsubishi Kasei Co., Ltd. in an automatic mortar to 100 μm is dispersed, and heat-treated at 150 ° C. for 2 hours to obtain an electrically responsive gel. Created. A voltage of 2 kV / mm was applied to this material at room temperature, and an attempt was made to measure the change in viscoelasticity in the same manner as in Example 1, but the current was too large to measure.

[Comparative Example 2] One-component thermosetting silicone gel manufactured by Toshiba Silicone Co., Ltd. (TSE3051: penetration 85)
100 parts by weight of fine barium titanate powder having an average particle size of 10 μm manufactured by Kyoritsu Kikai Co., Ltd. is dispersed in 100 parts by weight, and 150 ° C.
An electrically responsive gel was prepared by heat-treating for 2 hours. A voltage of 2 kV / mm was applied to this material at room temperature, and the change in viscoelasticity was measured in the same manner as in Example 1. G ′ and t
Neither anδ showed a significant change.

Example 4 20 parts by weight of the same fine powder as in Example 1 was dispersed in 10 parts by weight of silicone oil (TSF451-10000) manufactured by Toshiba Silicone Co., Ltd. to prepare an electrically responsive soft plastic material. 1.5k at room temperature for this material
When a voltage of V / mm was applied and the change in viscoelasticity was measured in the same manner as in Example 1, G ′ changed 80 times and tan δ changed 1/3 as shown in Table 1.

[0052]

[Table 1] The experiment was conducted at a frequency of 50 (rad / sec) and a strain of 3%.

Comparative Example 3 20 parts by weight of BaTiO ₃ was dispersed in 10 parts by weight of silicone oil (TSF451-10000) manufactured by Toshiba Silicone Co., Ltd. to prepare an electrically responsive soft plastic material. 1.5 kV / mm at room temperature for this material
When a change in viscoelasticity was measured in the same manner as in Example 1 by applying the voltage of No. 2, no significant change was shown in both G ′ and tan δ.

[0054]

EFFECTS OF THE INVENTION According to the present invention, a functional gel and a soft-plastic material, which have not been hitherto available, whose viscoelastic characteristics can be largely changed by the application of an electric field are obtained, and the energy absorption of a damper, a shock absorber, an engine mount, etc. It enables direct electrical control of general industrial parts and automotive parts for vibration control, and simplifies the structure of parts.

Claims (1)

[Claims] 1. An electrically responsive soft-plastic body or an electrically responsive gel in which fine powder that is electrically polarized by the action of an electric field is dispersed in an electrically insulating polymer material. A polymer having a viscosity of 10 ⁴ centistokes or more An electrically insulating polymer material selected from a partially cross-linked polymer gel medium having a penetration of 40 or more at room temperature B. The matrix phase is composed of fine particles non-uniformly dispersed type composite particles dispersed in a state in which a large amount of fine particles are present near the surface and a small amount on the center side or a state in which a small amount is present near the surface and a large amount on the center side. Fine powder having a conductivity of 1/10 or less, or fine particle uniform dispersion type composite particles in which fine particles are uniformly dispersed in a matrix phase, and the electric conductivity of the dispersed fine particles is 1/10 or less of the electric conductivity of the matrix phase. A fine powder comprising fine particle-dispersed composite particles in which fine particles are dispersed in a matrix phase, and the electric conductivity of the dispersed fine particles is 10 times or more the electric conductivity of the matrix phase. And a fine powder having an average particle size of 0.5 to 500 μm dispersed in at least one kind selected from Electrical responsive 軟塑 resistance, or electrically responsive gel.