JPH03215597A - Electroviscous fluid composition - Google Patents

Abstract

PURPOSE:To obtain the title compsn. generating a large shear stress by applying a relatively weak electric field and having an excellent stability of the generated shear stress with the elapse of time by dispersing specified particles as a dispersed phase in an electrically insulating dispersing medium. CONSTITUTION:100 pts.wt. sulfonated polymer particles obtd. by sulfonating arom. rings of a crosslinked polymer obtd. by polymerizing 5.0mol% or more vinyl arom. compd. having at least one alkoxy group in the arom. ring (e.g. methoxystyrene), 0.1-50.0mol% polyvinyl compd. (e.g. divinylbenzene) and, if necessary, other vinyl compd. (e.g. styrene) in the presence of a polymn. initiator at 50-100 deg.C for 2-40hr are incorporated with 10 pts.wt. or less water to obtain particles as a dispersed phase with a particle diameter of 0.1-100mum. Then, 100 pts.wt. said particles are dispersed in an electrically insulating dispersing medium (e.g. polydimethylsiloxane).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to electrorheological fluid compositions. More specifically, the present invention relates to an electrorheological fluid composition that can generate large shear stress even when a relatively weak electric field is applied, and has excellent stability of the generated shear stress over time.

(Prior Art) An electrorheological fluid is a fluid obtained by dispersing or suspending solid particles in an insulating dispersion medium, and its rheological or flow properties can be changed to viscoplastic type by applying an electric field change. It is a fluid whose properties change, and is generally known as a fluid that exhibits the so-called Winslow effect, in which the viscosity increases significantly and large shear stress is induced when an external electric field is applied. This Winslow effect has a characteristic of quick response, so electrorheological fluids are used in clutches and dampers.
Applications to brakes, shock absorber actuators, etc. are being attempted.

Conventionally, electrorheological fluid compositions include silicone oil,
It is known that solid particles such as cellulose, starch, soybean casein, Schifka gel, polystyrene ion exchange resin, cross-linked polyacrylate, etc. are dispersed in insulating oil such as diphenyl chloride or trans oil.

However, electrorheological fluid compositions using cellulose, starch, or soybean casein as the dispersed phase have a problem in that the shear stress obtained when an electric field is applied is small, so it is difficult to use a crosslinked polyacrylate as the dispersed phase. Electrorheological fluid compositions have a problem in that merely applying a relatively weak electric field does not induce practically sufficient shear stress.

In addition, electrorheological fluid compositions using an alkali metal salt type ion exchange resin of polystyrene sulfonic acid, which is one of the polystyrene-based ion exchange resins, as a dispersed phase can obtain large shear stress even when a relatively weak electric field is applied. However, there was a problem in that it lacked stability over time.

(Problems to be Solved by the Invention) The present invention solves the above problems that conventional electrorheological fluid compositions have.

Therefore, an object of the present invention is to provide an electrorheological fluid composition that generates a large shear stress even when a relatively weak electric field is applied, and maintains this stress over a long period of time, thus exhibiting excellent stability over time.

(Means and effects for solving the problems) The present invention provides a composition comprising dispersed phase particles dispersed in an insulating dispersion medium, wherein the dispersed phase particles have at least one alkoxy group on an aromatic ring. Aromatic aroma present in the polymerized crosslinked product (I) of a monomer mixture (A) containing a vinyl aromatic compound (a) and a polyvinyl compound (b) as essential components, and adding other vinyl compounds (c) as necessary. The sulfonated polymer particles obtained by sulfonating the group ring have 100%
Contains 10 parts by weight or less of water based on parts by weight,
and an electrorheological fluid composition characterized in that the proportion of the vinyl aromatic compound i) having at least one alkoxy group in the aromatic ring in the monomer mixture (A) is 5.0 mol% or more. It is.

The sulfonated polymer constituting the dispersed phase particles used in the present invention is one that has sulfonic acid groups that liberate cations and become sulfonic acid ions in the presence of a polar solvent such as water. There are no particular restrictions on the cations liberated in the presence of the polar solvent.

The average particle diameter of the dispersed phase particles used in the present invention is 0.1 to
It is preferably in the range of 100 μm.

When the average particle diameter of the dispersed phase particles is less than 0.1-μm, a problem may arise in that a large shear stress cannot be obtained when an electric field is applied to the prepared electrorheological fluid composition. In addition, the average particle diameter of the dispersed phase particles is 100 μm.
If the value exceeds 100%, the shear stress value obtained when a certain electric field is applied to the prepared electrorheological fluid composition may become irregular and difficult to stabilize.

In the present invention, it is necessary that the proportion of a vinyl aromatic compound (al) having at least one alkoxy group in the aromatic ring in the monomer mixture (A) is 5.0 mol% or more. Compound (a) is mixed with a monomer mixture (
By using it in a proportion of 5.0 mol% or more in A),
For example, even under mild sulfonation conditions of 80°C or less, dispersed phase particles can be easily obtained that generate large shear stress even by applying a relatively weak electric field and provide an electrorheological fluid composition with excellent stability of shear stress over time. It will be done. Furthermore, if the proportion of the vinyl aromatic compound (a) is less than 5.0 mol%,
Under industrially advantageous sulfonation conditions, an electrorheological fluid composition [-2] with inferior stability over time of shear stress f) cannot be obtained. For example, when cheap sulfuric acid is used as a sulfonating agent, sulfonation at high temperature and for a long time in the presence of a solvent that swells the polymerized crosslinked product (I) generates large shear stress due to the application of a relatively weak electric field. Even through such harsh sulfonation conditions, the effect of improving stability over time is not sufficient.

In the present invention, it is necessary that the monomer mixture (A) contains a polyvinyl compound (bl) of 0.1 to 50
．． It is preferably in the range of 0 mol%.

If the proportion of the polyvinyl compound (b) exceeds 50.0 mol%, sulfonation may not progress or large shear stress may occur when an electric field is applied to the electrorheological fluid composition using the obtained particles. There is a possibility that the problem of not being able to obtain the necessary information will occur. Further, the proportion of the polyvinyl compound (b) is 0.
When the amount is less than 1 mol %, a problem may occur in which particles adhere to each other when the crosslinked polymer obtained by polymerization is sulfonated.

At least one aromatic ring that can be used in the present invention
Vinyl aromatic compound (a) having alkoxy groups
Examples include methoxystyrene, dimethoxystyrene, trimethoxystyrene, ethoxystyrene, diethoxystyrene, triethoxystyrene, probyloxystyrene, dibrobyloxystyrene, triprobyloxystyrene, methoxymethylstyrene, methoxystyrene, Ethylstyrene, methoxymethylstyrene, ethoxymethylstyrene, ethoxyethylstyrene, propyloxymethylstyrene, propyloxyethylstyrene, methoxydimethylstyrene, methoxydiethylstyrene, vinylmethoxynaphthalene, vinyldimethoxynaphthalene, vinylethoxynaphthalene, Examples include vinyldiethoxynaphthalene, vinylmethoxymethylnaphthalene, vinylmethoxydimethylnaphthalene, vinyldimethoxymethylnaphthalene, vinylmethoxyethylnaphthalene, vinylmethoxydiethylnaphthalene, vinyldimethoxyethylnaphthalene, and one or more of these. can be used.

Polyvinyl compound (b) that can be used in the present invention
For example, divinylbenzene, divinyltoluene, divinylxylene, divinylethylbenzene, divinyldiethylbenzene, divinylpyrubenzene,
Polyvinyl aromatic hydrocarbons such as divinylnaphthalene, trihinylbenzene, trivinyltoluene, trivinylxylene, trivinylnaphthalene; ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, trimethylolpropane h IJ (
Examples include polyvinyl aliphatic compounds such as acrylate, N,N-methylenebisacrylamide, diallyl maleate, and diallyl adipate, and one or more of these -F can be used.

In the monomer mixture (A) in the present invention, a vinyl compound (c) other than the vinyl aromatic compound (a) having at least one alkoxy group in the aromatic ring or the polyvinyl compound (b) is blended as necessary. It is preferable that its constituent proportion is 94.9 mol% or less in the monomer mixture (A). Examples of such other vinyl compounds (C) include styrene, vinylnaphthalene,
Vinyl aromatic hydrocarbons such as vinyl anthracene and vinylphenanthrene; methylstyrene, ethylstyrene,
Monoalkylstyrene compounds such as probylstyrene, butylstyrene, pentylstyrene, hexylstyrene; dimethylstyrene, diethylstyrene, dipropylstyrene, methylethylstyrene, methylpropylstyrene, methylhexylstyrene, ethylbutylstyrene, ethylpropylstyrene, ethylhexylstyrene,
Dialkylstyrene compounds such as probylbutylstyrene; trimethylstyrene, triethylstyrene, triprobylstyrene, methyldiethylstyrene, dimethylethylstyrene, methylethylpropylstyrene, methyldipropylstyrene, dimethylbutylstyrene, ethyldipropylstyrene, jetylpropylstyrene Trialkylstyrene compounds such as: vinylmonoalkylnaphthalene compounds such as vinylmethylnaphthalene, vinylethylnaphthalene, vinylpropylnaphthalene; vinyldialkylnaphthalene compounds such as vinyldimethylnaphthalene, vinyljetylnaphthalene, vinyldipropylnaphthalene, vinylmethylethylnaphthalene Vinyltrialkylnaphthalene compounds such as vinyltrimethylnaphthalene, vinyltriethylnaphthalene, vinyltriprobylnaphthalene, vinylmethyldiethylnaphthalene, vinyldimethylethylnaphthalene, vinylmethylethylpropylnaphthalene; phenoxystyrene, phenoxymethylstyrene, phenoxy Aryloxylated vinyl aromatic compounds such as ethylstyrene, phenoxydimethylstyrene, and phenoxydiethylstyrene; Olefinic hydrocarbons such as ethylene, propylene, isoprene, butadiene, vinyl chloride, and chloroprene, or halogen-substituted products thereof; Methyl (meth)acrylate, ethyl (
Ester compounds of unsaturated carboxylic acids such as meth)acrylate; Vinyl ester compounds of monovalent carboxylic acids such as vinyl acetate and vinyl propionate; (meth)acrylamide, diacetone acrylamide, methylolated (
Unsaturated amide compounds or derivatives thereof such as meth)acrylamide; Unsaturated cyanide compounds such as (meth)acrylonitrile and crotonitrile; Unsaturated alcohol compounds such as (meth)allylic alcohol and crotonal alcohol; Saturated monobasic acid;
Examples include unsaturated dibasic acids such as maleic acid, fumaric acid, and itaconic acid; monoester compounds of monohydric alcohols and unsaturated dibasic acids such as monomethyl maleate and monoallyl maleate; One or more types can be used from among these.

The shape of the dispersed phase particles used in the present invention is preferably spherical or ellipsoidal. When the shape of the dispersed phase particles is other than spherical or ellipsoidal, there is a problem that a large shear stress cannot be obtained when an electric field is applied to the prepared electrorheological fluid composition, or it is difficult to continue applying the electric field. Problems may arise in that the stability over time in the state is poor.

The method for producing the crosslinked polymer (I) used as an intermediate for obtaining the sulfonated polymer in the present invention is not particularly limited, and may include known polymerization methods such as suspension polymerization, emulsion polymerization, Methods such as dispersion polymerization, solution polymerization, and bulk polymerization can be used, but suspension polymerization and emulsion polymerization are preferred since spherical or ellipsoidal polymerized crosslinked products (I) can be easily obtained.

When a suspension polymerization method is used as a polymerization method when producing the polymerized crosslinked product (I) used in the present invention, there are no particular restrictions on the polymerization conditions.

Water or the like is usually used as a dispersion medium for suspension polymerization.

Dispersants for suspension polymerization are usually known ones such as polyvinyl alcohol, carboxymethyl cellulose, ammonium salt of styrene-maleic anhydride copolymer, bentonite, sodium poly(meth)acrylate, and poly(diallylmethylammonium chloride). can be used.

Examples of polymerization initiators for suspension polymerization include benzoyl peroxide, tertiary butyl hydroxy peroxide, cumene peroxide, lauroyl peroxide, methyl ethyl ketone peroxide,
Peroxides such as tertiary butyl perphthalate and turnipyl peroxide; azobisisobutyronitrile, azobisisobutyramide, 2,2'-azobis(2,4-
Examples include azo compounds such as dimethylmaleronitrile), azobis(α-dimethylmaleronitrile), and azobis(α-methylbutyronitrile), and one or more of these can be used.

During suspension polymerization, if necessary, a known emulsion polymerization inhibitor can be used to suppress the generation of fine particles.

Suspension polymerization is usually carried out at a temperature in the range of 50 to 100°C for about 2 to 30 hours.

For suspension polymerization, for example, water and a dispersant are charged, a mixture of monomers in which a polymerization initiator is dissolved is added to the mixture under stirring, and the particle size is controlled using a disperser or stirring device. , carried out at a predetermined temperature under suspension conditions.

When emulsion polymerization is used to produce the crosslinked polymer (I) used in the present invention, there are no particular limitations on the polymerization conditions.

Water or the like is usually used as a solvent for emulsion polymerization.

As the emulsifier for emulsion polymerization, known ones such as surfactants such as sodium lauryl sulfonate and polyoxyethylene stearate can be used.

As the polymerization initiator for emulsion polymerization, commonly known initiators such as sodium persulfate and ammonium persulfate can be used.

Emulsion polymerization is usually carried out at a temperature in the range of 50 to 100°C for about 2 to 40 hours.

As the emulsion polymerization operation, known methods such as seed polymerization, one-time charge polymerization, monomer addition polymerization, and emulsion addition polymerization can be used.

To carry out the seed polymerization method, seed particles, water, an emulsifier, etc. are usually first put into a reaction vessel, and the mixture is uniformly dispersed with stirring, after which a part or, if necessary, all of the monomer mixture is added. Next, after heating to a predetermined temperature, a polymerization initiator is added to start the reaction. Furthermore, the remainder of the monomer mixture is added continuously or intermittently, and the process is carried out at a predetermined temperature under an emulsified state.

The polymeric crosslinked product (I) in the present invention may be a substantially non-porous polymeric crosslinked product called a gel type, or a known porous polymeric crosslinked product that imparts porosity to the polymerized crosslinked product obtained during polymerization. A porous crosslinked polymer obtained by polymerizing a monomer mixture in the coexistence of a quality-forming agent, such as a swelling organic solvent, a non-swelling organic solvent, a linear polymer soluble in the monomer, or a mixture thereof. There may be.

The sulfonated polymer constituting the dispersed phase particles used in the present invention is a polymer crosslinked product (I
) is obtained by sulfonation using a known method. Furthermore, if a particulate material obtained by a suspension polymerization method or an emulsion polymerization method is used as the polymer (I), particles of a sulfonated polymer suitable as dispersed phase particles in the present invention can be easily obtained by sulfonation. be able to.

The sulfonation reaction is carried out in the absence of a solvent, in the presence of a non-swelling solvent for the polymerized crosslinked product (I), or in the presence of a non-swellable solvent for the polymerized crosslinked product (I).
Kokichi can be carried out in the presence of a swelling solvent.

The non-swelling solvent for the crosslinked polymer (I) may be any solvent that does not swell the crosslinked polymer (I) and is inert to the sulfonating agent, such as hexane, cyclohexane, ligroin, etc. Examples include aliphatic hydrocarbons.

The swelling solvent for the crosslinked polymer (I) may be any solvent that swells the crosslinked polymer (I) and is inert to the sulfonating agent, such as dichloroethane, trichloroethylene, and tetrachloroethane. , nitrobenzene,
Examples include propylene dichloride and carbon tetrachloride.

The amount of these solvents used is preferably within the range of 1000 parts by weight or less based on 100 parts by weight of the polymeric crosslinked product (I).

The sulfonating agent is not particularly limited, and examples thereof include sulfuric acid, oleum, chlorosulfuric acid, and sulfur dioxide, and one or more of these can be used.

The sulfonation reaction is preferably carried out at a temperature of 80°C or lower due to industrial practicality such as restrictions on the material of the reactor, and in the present invention, even under such mild sulfonation conditions, an electric reactor with excellent stability of shear stress over time is used. Dispersed phase particles are obtained giving a viscous fluid composition.

After the particles of the sulfonated polymer obtained by sulfonating the polymer crosslinked product (I) are separated from the sulfonating agent, they are thoroughly treated with a large amount of water to remove the acid etc. remaining in the particles. It is better to wash it.

Next, if necessary, the cation of the sulfonic acid group can be converted from a proton to a suitable cation species by a method such as neutralization or ion exchange.

The cation of the sulfonic acid group present in the sulfonated polymer constituting the dispersed phase particles used in the present invention is not particularly limited, and includes, for example, hydrogen; alkali metals such as lithium, sodium, and potassium; magnesium, calcium, etc. Alkaline earth metals; Group IIIA metals such as aluminum; ■Group A metals such as tin and lead: Cation species such as transition metals such as zinc and iron, or ammonium, organic quaternary ammonium, pyridinium, guadinium, etc. can be used, and one or more types can be used from among these.

The dispersed phase particles used in the present invention can be obtained by incorporating water into the particles of the sulfonated polymer described above.

In the electrorheological fluid composition of the present invention, a small amount of water is contained in the dispersed phase particles, so that a large shear stress is induced when an electric field is applied.

In the present invention, the amount of water in the dispersed phase particles must be 10 parts by weight or less based on parts by weight of the particles IN. 1 water
If it exceeds 0 parts by weight, dispersed phase particles may adhere to each other,
Alternatively, the insulating properties of the prepared electrorheological fluid composition are reduced, so that a large current may flow when an electric field is applied, which is undesirable.

Insulating dispersion media that can be used in the present invention include:
There are no particular limitations, and examples include silicone oils such as polydimethylsiloxane and polyphenylmethyldioxane; hydrocarbons such as liquid paraffin, decane, dodecane, methylnaphthalene, dimethylnaphthalene, ethylnaphthalene, biphenyl, decalin, and partially hydrogenated triphenyl;
Ether compounds such as diphenyl ether: chlorobenzene, dichlorobenzene, trichlorobenzene, bromobenzene, dibromobenzene, chloronaphthalene, dichloronaphthalene, promonaphthalene, chlorobiphenyl, dichlorobiphenyl, trichlorobiphenyl, promobiphenyl, chlorodiphenylmethane, dichlorodiphenylmethane, trichlorodiphenyl Halogenated hydrocarbons such as enylmethane, promodiphenylmecune, chlorodecane, dichlorodecane, trichlorodecane, promodecane, chlorododecane, dichlorododecane, bromododecane;
Halogenated diphenyl ether compounds such as chlorodiphenyl ether, dichlorodiphenyl ether, trichlorodiphenyl ether, and promodiphenyl ether;
Examples include fluorides such as Daifloil (manufactured by Daikin Industries, Ltd.) and Demnum (manufactured by Daikin Industries, Ltd.); ester compounds such as dioctyl phthalate, trioctyl trimellitate, and dibutyl sebacate; One or more of these can be used.

The electrorheological fluid composition of the present invention is made by dispersing the above-mentioned dispersed phase particles in an insulating dispersion medium, and the ratio of the dispersed phase particles to the insulating dispersion medium in the composition is set to 100 parts by weight of the former. The latter is preferably in the range of 50 to 500 parts by weight. If the amount of the dispersion medium exceeds 500 parts by weight, the shear stress obtained when an electric field is applied to the prepared electrorheological fluid composition may not be sufficiently large. Furthermore, if the amount of the dispersion medium is less than 50 parts by weight, the fluidity of the prepared composition itself may be reduced, making it difficult to use it as an electrorheological fluid.

In the present invention, for example, surfactants, polymer dispersants, polymer thickeners, etc. Various additives can be added to the composition.

(Effects of the Invention) The electrorheological fluid composition of the present invention has excellent stability over time, allowing a large shear stress to be obtained even when a relatively weak external electric field is applied, and maintaining the generated shear stress over a long period of time. Because of its excellent properties, it can be effectively used in clutches, damper brakes, shock absorber actuators, etc.

(Examples) The present invention will be explained below with reference to Examples, but the scope of the present invention is not limited only to these Examples.

Reference Example 1 A 3L four-necked separable flask equipped with a stirrer, a reflux condenser, and a thermometer was charged with 1.21 g of water and mixed with polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Kuraray Poval @ PVA).
-205) After adding and dissolving 16.0 g, further add 300 g of methoxystyrene and 30 g of industrial divinylbenzene (manufactured by Wako Pure Chemical Industries, Ltd., a mixture of 55% by weight of divinylbenzene and 35% by weight of ethylstyrene). and 4 g of abbisisobutyronitrile were added.

Thereafter, the contents in the flask were dispersed at a stirring speed of 650 rpm, and polymerization was carried out at 70° C. for 13 hours.

The obtained solid substance was filtered, washed with water, and then dried at 80° C. for 12 hours using a hot air drier to obtain a spherical polymer crosslinked product (hereinafter referred to as polymer crosslinked product (I)). )305g
I got it.

Reference Example 2 1.2 liters of water was charged into a 3-liter four-piece removable flask equipped with a stirrer, a reflux condenser, and a thermometer, and polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Kuraray Poval @PVA) was added.
-205) After adding and dissolving 10.0 g, a mixture consisting of 200 g of methoxystyrene, 50 g of styrene, 30 g of the same industrial divinylbenzene as used in Reference Example 1, and 4 g of azobisisobutyronitrile was added.

Thereafter, the contents in the flask were dispersed at a stirring speed of 500 rpm, and polymerization was carried out at 70° C. for 12 hours.

The obtained solid substance was filtered, thoroughly washed with water, and then dried at 80° C. for 12 hours using a hot air drier to obtain a spherical polymer crosslinked product (hereinafter referred to as polymer crosslinked product (2)). } 255
I got g.

Reference Example 3 1.21 g of water was charged into a 3 liter four-piece removable flask equipped with a stirrer, a reflux condenser and a thermometer, and polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Kuraray Bobal PVA) was added.
-205) After adding and dissolving 16.0 g, further add 30 g of methoxystyrene, 130 g of styrene, 80 g of methylstyrene, 60 g of industrial divinylbenzene as used in Reference Example 1, 300 g of isooctane, and 1. A mixture consisting of 12 g of Lil was added. Thereafter, the contents in the flask were dispersed using a disperser (rotation speed: 5000 rpm) and polymerized at 70° C. for 11 hours. The obtained solid substance was filtered, washed with acetone and water, and then dried at 80°C for 12 hours using a hot air dryer. 3). }280g was obtained.

Reference Example 4 In a 300 ml four-necked flask equipped with a stirrer, reflux condenser, thermometer and dropping atom, 50 ml of water, 0.4 g of sodium lauryl sulfonate and 1.5 g of dodecane were added.
After charging 0 g, the mixture was emulsified using a disperser. Furthermore, after adding 50 ml of water, 0.2 g of sodium persulfate, 30 g of methoxystyrene, 15 g of styrene, and 15 g of the same industrial divinylbenzene used in Reference Example 1, the mixture was heated at 50° C. for 8 hours with stirring to polymerize. As a result, 160 ml of an emulsion of seed particles was obtained.

Next, 1.2 liters of water was charged into a 3 liter four-necked flask equipped with a stirrer, a reflux condenser, a thermometer, and a dropping funnel.
After adding 160 ml of the seed particle emulsion prepared previously and 2.8 g of sodium lauryl sulfonate, they were uniformly dispersed while stirring. Thereafter, while maintaining the rotation speed of the stirrer at 250 rpm, the mixture was heated to 70° C., and 2 g of sodium persulfate dissolved in 10 ml of water was added. Next, a mixture consisting of 120 g of methoxystyrene, 60 g of styrene, and 60 g of industrial divinylbenzene as used in Reference Example 1 was added dropwise over 18 hours. Furthermore, 70℃
After reacting for 5 hours, the temperature was raised to 90°C, and the reaction was terminated after 3 hours.

The solid content of the obtained latex was separated by filtration and dried at 80°C for 12 hours using a hot air dryer to obtain a spherical crosslinked polymer {
Hereinafter, this will be referred to as a polymerized crosslinked product (4). } 265g was obtained.

Reference Example 5 A 3-liter four-neck separable flask equipped with a stirrer, a reflux condenser, and a thermometer was charged with 1 to 2 liters of water, and polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Kuraray Poval" PV) was added.
A-205) After adding and dissolving 16.0g, further,
A mixture consisting of 90 g of methoxystyrene, 120 g of industrial divinylbenzene as used in Reference Example 1, and 4 g of azobisisobutyronitrile was added.

Thereafter, the contents in the flask were dispersed at a stirring speed of 400 rpm and polymerized at 70° C. for 12 hours.

The obtained solid substance was filtered, thoroughly washed with water, and then dried at 80° C. for 12 hours using a hot air drier to obtain a spherical polymer crosslinked product (hereinafter referred to as polymer crosslinked product (5)). } 282
I got g.

Reference Example 6 A 3-liter four-necked separable flask equipped with a stirrer, a reflux condenser, and a thermometer was charged with 1.2 liters of water and mixed with polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Kuraray Bobal PVA).
-205) After adding and dissolving 16.0 g, further add 50 g of dimethoxystyrene, 150 g of styrene, 60 g of methylstyrene, 40 g of industrial divinylbenzene as used in Reference Example 1, and 4 g of azobisisobutyronitrile. A mixture of was added. After that, 670rp
Disperse the contents in the flask at a stirring speed of 70°C.
Polymerization was carried out for 14 hours. The obtained solid was filtered, thoroughly washed with water, and then dried at 80°C for 12 hours using a hot air drier.
). }291g was obtained.

Reference Example 7 A 3-liter four-necked separable flask equipped with a stirrer, a reflux condenser, and a thermometer was charged with 1.2 g of water, and polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Kuraray Poval" Pv) was added.
A-205) After adding and dissolving 16.0g, further,
150 g of ethoxystyrene 1 70 g of styrene 1 50 g of chlorostyrene 30 g of the same industrial divinylbenzene used in Reference Example 1 and 4 azobisisobutyronitrile
A mixture consisting of g was added. After that, disperser (rotation speed.
10,000 rpm) to disperse the contents in the flask, and polymerized at 70° C. for 13 hours. The obtained solid matter was filtered, thoroughly washed with water, and heated to 80°C using a hot air dryer.
The mixture was dried for 12 hours to form a spherical crosslinked polymer (hereinafter referred to as a crosslinked polymer (7)). } 287g was obtained.

Reference Example 8 1.21 liters of water in a 3L four-neck separable flask equipped with a stirrer, reflux condenser, and thermometer! Prepare polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Kuraray Bobal PV)
A-205) After adding and dissolving 16.0g, further,
Methoxymethylstyrene 170g, styrene 100g,
The same industrial divinylbenzene 30 used in Reference Example 1
g1 polystyrene (manufactured by Wako Pure Chemical Industries, Ltd., degree of polymerization: 160
0-1800) and 4 g of azobisisobutyronitrile were added. Thereafter, the contents in the flask were dispersed using a disperser (rotation speed: 8,00 rpm), and polymerization was performed at 70° C. for 13 hours. The obtained solid was filtered, thoroughly washed with acetone and water, and then dried at 80°C for 12 hours using a hot air drier. ). } 289
I got g.

Comparative Reference Example 1 A 3L four-necked separable flask equipped with a stirrer, a reflux condenser, and a thermometer was charged with 1.24 g of water, and polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Kuraray Bovar @ PVA) was added.
-2 0 5)] - 6.0 g was added and dissolved, and then a mixture consisting of 300 g of styrene, 30 g of the same industrial divinylbenzene as used in Reference Example 1, and 4 g of azobisisobutyronitrile was added. added. After that, 67
Disperse the contents in the flask at a stirring speed of 0 rpm,
Polymerization was carried out at 80°C for 7 hours. The obtained solid was filtered, thoroughly washed with water, and then dried at 80°C for 12 hours using a hot air dryer. ). }305g was obtained.

Example 1 50 g of the polymerized crosslinked product (I) obtained in Reference Example 1 and 250 g of dichloroethane were placed in a 2I four-necked separable flask equipped with a stirrer and a thermometer, and heated to 0° C. using a water bath while stirring. It was cooled to

Next, after adding 250 g of 98% by weight concentrated sulfuric acid,
The mixture was stirred for a minute to form a uniform dispersion. Then, it was removed from the water bath and stirred at room temperature (20° C.) for 24 hours to perform a sulfonation reaction. Thereafter, the reaction mixture was poured into water at 0°C, filtered, and washed with water and acetone.

The obtained solid was dissolved in a 10% by weight aqueous sodium hydroxide solution.
After neutralizing with 40 ml, the solution was thoroughly washed with water. Then,
Dry at 80°C for 10 hours using a vacuum dryer, weighing 78g.
spherical dispersed phase particles {hereinafter referred to as dispersed phase particles (I). } was obtained.

The average particle diameter of the obtained dispersed phase particles (I) was measured using a particle size distribution analyzer (SALD-1000, manufactured by Shimadzu Corporation) and found to be 45 μm. Dispersed phase particles (I)
When the ion exchange capacity of the ion exchange capacity was measured by neutralization titration, 3
．． The amount was 9 equivalent/g.

The water content in the obtained dispersed phase particles (I) was measured using a Karl Fischer moisture meter (manufactured by Kyoto Denshi Kogyo ■, MPS3P) and found to be 2.4 parts by weight.

30 g of the obtained dispersed phase particles (I) was
(Partially hydrogenated triphenyl manufactured by Nippon Steel Chemical Co., Ltd.)
70 g of the electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (I)). } was obtained.

Example 2 The polymerized crosslinked product obtained in Reference Example 2 (
2) 50 g and 300 g of nitrobenzene were charged, and the mixture was cooled to 0° C. using a water bath while stirring. Next, 250 g of chlorosulfuric acid was added from the dropping funnel over 2 hours,
A uniform dispersion was obtained. Next, the mixture was removed from the water bath and stirred at room temperature (20° C.) for 10 hours to carry out a sulfonation reaction. Thereafter, the reaction mixture was poured into water at 0°C, filtered, and washed with water and acetone.

The obtained solid was dissolved in a 10% by weight lithium hydroxide aqueous solution.
After neutralizing with 0 ml, the solution was thoroughly washed with water.

Next, it was dried at 80° C. for 10 hours using a vacuum dryer to obtain 78 g of spherical dispersed phase particles (hereinafter referred to as dispersed phase particles (2)). } was obtained.

The average particle diameter of the obtained dispersed phase particles (2) was measured using a particle size distribution analyzer and was found to be 55 μm. The ion exchange capacity of the dispersed phase particles (2) was measured by neutralization titration and was found to be 4.6 equivalents/g.

The water content in the obtained dispersed phase particles (2) was measured using a Karl Fischer moisture meter and was found to be 2.0 parts by weight.

30 g of the obtained dispersed phase particles (2) was mixed with 70 g of bromobenzene.
The electrorheological fluid composition of the present invention is mixed and dispersed in
Hereinafter, this will be referred to as fluid composition (2). } was obtained.

Example 3 The polymerized crosslinked product obtained in Reference Example 3 (
3) 50 g and 500 g of hexane were charged, and the mixture was cooled to 0° C. using a water bath while stirring. Next, 200 g of chlorosulfuric acid was added from the dropping funnel over 2 hours to form a uniform dispersion. It is then removed from the water bath and room temperature (20
℃) for 24 hours to carry out the sulfonation reaction.

After that, the reaction mixture was poured into water at 0 °C, filtered, and then
Washed with water and acetone.

The obtained solid was dissolved in a 10% by weight aqueous sodium hydroxide solution.
After neutralizing with 20 ml, the solution was thoroughly washed with water. Next, it was dried at 80°C for 10 hours using a vacuum dryer,
74g of spherical dispersed phase particles (hereinafter referred to as dispersed phase particles)
3). } was obtained.

The average particle diameter of the obtained dispersed phase particles (3) was measured using a particle size distribution analyzer and was found to be 10 μm. Measure the ion exchange capacity of dispersed phase particles (3) by neutralization titration.
7, the result was 3.8 equivalents/g.

The water content in the obtained dispersed phase particles (3) was measured using a Karl Fischer moisture meter and was found to be 2.5 parts by weight.

30 g of the obtained dispersed phase particles (3) were mixed and dispersed in 70 g of Shin-Etsu silicone oil ΦKF96-20CS (dimethyl silicone oil manufactured by Shin-Etsu Chemical Co., Ltd.) to form the electrorheological fluid composition of the present invention (hereinafter referred to as this). The fluid composition (
3). } was obtained.

Example 4 50 g of the polymer crosslinked product (3) obtained in Reference Example 3 and 500 g of 98% by weight concentrated sulfuric acid were charged into a 1 liter four-necked separable flask equipped with a stirrer and a thermometer, and stirred for 30 minutes. A uniform dispersion was obtained. Next, the contents in the flask were heated to 70° C., and heated and stirred at the same temperature for 24 hours to perform a sulfonation reaction. Thereafter, the reaction mixture was poured into water at 0° C., filtered, and washed with water.

The obtained solid was dissolved in a 10% by weight aqueous sodium hydroxide solution.
After neutralizing with 10 ml, the solution was thoroughly washed with water. Then,
Dry at 80°C for 10 hours using a vacuum dryer, weighing 73g.
spherical dispersed phase particles {hereinafter referred to as dispersed phase particles (4). } was obtained.

The average particle diameter of the obtained dispersed phase particles (4) was measured using a particle size distribution analyzer and was found to be 10 μm. The ion exchange capacity of the dispersed phase particles (4) was measured by neutralization titration and was found to be 3.6 equivalents/g.

The water content in the obtained dispersed phase particles (4) was measured using a Karl Fischer moisture meter and was found to be 2.6 parts by weight.

30g of the obtained dispersed phase particles (4)
(A mixture of biphenyl and diphenyl ether manufactured by Nippon Steel Chemical Co., Ltd.) was mixed and dispersed in 70 g of the electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (4)). } was obtained.

Example 5 The polymerized crosslinked product obtained in Reference Example 4 (
4) 50g of tetrachloride and 250g of ethane were charged, and the mixture was cooled to 0°C using a water bath while stirring. Then,
300 g of chlorosulfuric acid was added from the dropping funnel over 2 hours to form a uniform dispersion. Then remove from the water bath and
The mixture was stirred at room temperature (20° C.) for 20 hours to carry out the sulfonation reaction. Thereafter, the reaction mixture was poured into water at 0°C, filtered, and washed with water and acetone.

The obtained solid was dissolved in a 10% by weight potassium hydroxide aqueous solution 2
After neutralizing with 10 ml, the solution was thoroughly washed with water.

Next, it was dried at 80° C. for 10 hours using a vacuum dryer to obtain 88 g of spherical dispersed phase particles (hereinafter referred to as dispersed phase particles (5)). } was obtained.

The average particle diameter of the obtained dispersed phase particles (5) was measured using a particle size distribution analyzer and was found to be 5 μm. The ion exchange capacity of the dispersed phase particles (5) was measured by neutralization titration and was found to be 4.0 equivalent/g.

The water content in the obtained dispersed phase particles (5) was measured using a Karl Fischer moisture meter and was found to be 2.1 parts by weight.

30 g of the obtained dispersed phase particles (5) were mixed and dispersed in 70 g of 1.2.4 monotrichlorobenzene to form the electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (5)). } was obtained.

Example 6 The polymerized crosslinked product obtained in Reference Example 5 (
5) 50 g and 200 g of dichloroethane were charged, and the mixture was cooled to 0° C. using a water bath while stirring. Next, 300 g of chlorosulfuric acid was added from the dropping funnel over 2 hours,
A uniform dispersion was obtained. Next, the mixture was removed from the water bath and stirred at room temperature (20° C.) for 20 hours to perform a sulfonation reaction. Thereafter, the reaction mixture was poured into water at 0°C, filtered, and washed with water and acetone.

The obtained solid was neutralized with 30 g of pyridine and then thoroughly washed with water. Next, using a vacuum dryer, it was dried at 80°C for 10 hours to obtain 101 g of spherical dispersed phase particles {hereinafter referred to as
These are called dispersed phase particles (6). } was obtained.

The average particle diameter of the obtained dispersed phase particles (6) was measured using a particle size distribution analyzer and was found to be 75 μm. The ion exchange capacity of the dispersed phase particles (6) was measured by neutralization titration and was found to be 3.4 equivalents/g.

The water content in the obtained dispersed phase particles (6) was measured using a Karl Fischer moisture meter and was found to be 2.2 parts by weight.

30 g of the obtained dispersed phase particles (6) were added to 70 g of liquid paraffin.
The electrorheological fluid composition of the present invention is mixed and dispersed in
Hereinafter, this will be referred to as fluid composition (6). } was obtained.

Example 7 The polymerized crosslinked product obtained in Reference Example 6 (
6) 50 g and 250 g of dichloroethane were charged, and the mixture was cooled to 0° C. using a water bath while stirring. Next, 250 g of chlorosulfuric acid was added from the dropping funnel over 2 hours,
A uniform dispersion was obtained. Next, the mixture was removed from the water bath and stirred at room temperature (20° C.) for 15 hours to carry out a sulfonation reaction. Thereafter, the reaction mixture was poured into water at 0° C., filtered, and washed with water and acetone.

The obtained solid was dissolved in a 10% by weight aqueous sodium hydroxide solution.
After neutralizing with 60 ml, the solution was thoroughly washed with water. Next, dry at 80°C for 10 hours using a vacuum dryer.
, 85 g of spherical dispersed phase particles {hereinafter referred to as dispersed phase particles (7). } was obtained.

The average particle diameter of the obtained dispersed phase particles (7) was measured using a particle size distribution analyzer and was found to be 40 μm. The ion exchange capacity of the dispersed phase particles (7) was measured by neutralization titration and was found to be 4.3 equivalents/g.

The water content in the obtained dispersed phase particles (7) was measured using a Carl 7 Ischer moisture meter and was found to be 2.3 parts by weight.

30 g of the obtained dispersed phase particles (7) were mixed and dispersed in 70 g of Shin-Etsu silicone oil KF96-50CS (dimethyl silicone oil manufactured by Shin-Etsu Chemical Co., Ltd.), and the electrorheological fluid composition of the present invention (hereinafter referred to as this) It is called fluid composition (7). } was obtained.

Example 8 The polymerized crosslinked product obtained in Reference Example 7 (
7) 50 g and 200 g of nitrobenzene were charged, and the mixture was cooled to 0° C. using a water bath while stirring. Next, 300 g of chlorosulfuric acid was added from the dropping funnel over 2 hours,
A uniform dispersion was obtained. Next, the mixture was removed from the water bath and stirred at room temperature (20° C.) for 12 hours to carry out a sulfonation reaction. Thereafter, the reaction mixture was poured into water at 0°C, filtered, and washed with water and acetone.

The obtained solid was dissolved in a 10% by weight potassium hydroxide aqueous solution 2
After neutralizing with 0.0 ml, the solution was thoroughly washed with water.

Next, it was dried at 80° C. for 10 hours using a vacuum dryer to obtain 88 g of spherical dispersed phase particles (hereinafter referred to as dispersed phase particles (8)). } was obtained.

The average particle diameter of the obtained dispersed phase particles (8) was measured using a particle size distribution analyzer and was found to be 5 μm. The ion exchange capacity of the dispersed phase particles (8) was measured by neutralization titration and was found to be 3.8 equivalents/g.

The water content in the obtained dispersed phase particles (8) was measured using a Karl Fischer moisture meter and was found to be 2.0 parts by weight.

30g of the obtained dispersed phase particles (8)
(Partially hydrogenated triphenyl manufactured by Nippon Steel Chemical) 70
The electrorheological fluid composition of the present invention is mixed and dispersed in
Hereinafter, this will be referred to as fluid composition (8). } was obtained.

Example 9 The polymerized crosslinked product obtained in Reference Example 8 (
8) 50 g of tetrachloride and 250 g of ethane were charged, and the mixture was cooled to 0° C. using a water bath while stirring. Then,
After adding 200 g of 98% by weight concentrated sulfuric acid, the mixture was stirred for 30 minutes to obtain a uniform dispersion. Then remove from the water bath and
The mixture was heated and stirred at 70° C. for 20 hours to carry out a sulfonation reaction. Thereafter, the reaction mixture was poured into water at 0°C, filtered, and washed with water and acetone.

The obtained solid was dissolved in a 10% by weight aqueous lithium hydroxide solution.
After neutralizing with ml, the solution was thoroughly washed with water.

Next, it was dried at 80° C. for 10 hours using a vacuum dryer to obtain 69 g of spherical dispersed phase particles (hereinafter referred to as dispersed phase particles (9)). } was obtained.

The average particle diameter of the obtained dispersed phase particles (9) was measured using a particle size distribution analyzer and was found to be 8 μm. The ion exchange capacity of the dispersed phase particles (9) was measured by neutralization titration and was found to be 3.7 equivalents/g.

The water content in the obtained dispersed phase particles (9) was measured using a Karl Fischer moisture meter and was found to be 2.3 parts by weight.

30 g of the obtained dispersed phase particles (9) was mixed with 70 g of bromobenzene.
The electrorheological fluid composition of the present invention is mixed and dispersed in
Hereinafter, this will be referred to as fluid composition (9). } was obtained.

Comparative Example 1 250 g of dichloroethane was charged into a 2 liter four-necked separable flask equipped with a stirrer and a thermometer, and cooled to 0° C. using a water bath while stirring.

Next, after adding 250 g of 98% by weight concentrated sulfuric acid and 50 g of the comparative polymer crosslinked product (I) obtained in Comparative Reference Example 1,
The mixture was stirred for a minute to form a uniformly dispersed liquid. Next, the mixture was taken out from the water bath and stirred at room temperature (20° C.) for 24 hours to perform a sulfonation reaction.

Thereafter, the reaction mixture was poured into water at 0°C, separated by filtration, and washed with water.

The obtained solid was dissolved in a 10% by weight aqueous sodium hydroxide solution 3
After neutralizing with 0 ml, the solution was thoroughly washed with water. Next, using a vacuum dryer, it was dried at 80°C for 10 hours, and 51 g of spherical comparative dispersed phase particles (hereinafter referred to as comparative dispersed phase particles)
I). } was obtained.

The average particle diameter of the obtained comparative dispersed phase particles (I) was measured using a particle size distribution analyzer and was found to be 45 μm.

The ion exchange capacity of the comparative dispersed phase particles (I) was measured by neutralization titration and was found to be 0.9 equivalent/g.

The water content in the obtained comparative dispersed phase particles (I) was measured using a Karl Fischer moisture meter and was found to be 1.1 parts by weight.

30g of the obtained comparative dispersed phase particles (I) was placed in Therm-S●9
00 (partially hydrogenated triphenyl manufactured by Nippon Steel Chemical)
A comparative electrorheological fluid composition (hereinafter referred to as comparative fluid composition (I)) was prepared by mixing and dispersing it in 70 g. } was obtained.

Comparative Example 2 250 g of dichloroethane was charged into a 2 liter four-necked separable flask equipped with a stirrer and a thermometer, and cooled to 0° C. using a water bath while stirring.

Next, 250 g of 98% by weight concentrated sulfuric acid and 50 g of the comparative polymerized crosslinked product (I) obtained in Comparative Reference Example 1 were added, followed by stirring for 30 minutes to obtain a uniform dispersion liquid.

Next, the contents in the flask were heated to 80° C., and heated and stirred at the same temperature for 24 hours to perform a sulfonation reaction. Thereafter, the reaction mixture was poured into 0°C water, filtered, and washed with water.

The obtained solid was dissolved in a 10% by weight aqueous sodium hydroxide solution.
After neutralizing with 70 ml, the solution was thoroughly washed with water.

Next, it was dried at 80° C. for 10 hours using a vacuum dryer to obtain 87 g of spherical comparative dispersed phase particles (hereinafter referred to as comparative dispersed phase particles (2)). } was obtained.

The average particle diameter of the obtained comparative dispersed phase particles (2) was measured using a particle size distribution analyzer and found to be 4571 m. The ion exchange capacity of the comparative dispersed phase particles (2) was measured by neutralization titration and was found to be 4.4 equivalents/g.

The water content in the obtained comparative dispersed phase particles (2) was measured using a Karl Fischer moisture meter and was found to be 2.7 parts by weight.

30g of the obtained comparative dispersed phase particles (2) was placed in Therm-S●9
00 (partially hydrogenated triphenyl manufactured by Nippon Steel Chemical)
A comparative electrorheological fluid composition (hereinafter referred to as comparative fluid composition (2)) was prepared by mixing and dispersing it in 70 g. } was obtained.

Comparative Example 3 Amberlite IR-124 (manufactured by Tokyo Organic Chemical Industry Co., Ltd.), which is a sodium polystyrene sulfonate ion-type ion exchange resin, was dried at 150°C for 3 hours, then crushed and classified to obtain an amorphous comparative product. dispersed phase particles {hereinafter referred to as comparative dispersed phase particles (3). } was obtained.

The average particle diameter of the obtained comparative dispersed phase particles (3) was measured using a particle size distribution analyzer and was found to be 45 μm.

The ion exchange amount of the comparative dispersed phase particles (3) was measured by neutralization titration and was found to be 4.4 equivalents/g.

The water content in the obtained comparative dispersed phase particles (3) was measured using a Karl Fischer moisture meter and was found to be 2.8 parts by weight.

30g of the obtained comparative dispersed phase particles (2) was added to Therm-S ■9
00 (partially hydrogenated triphenyl manufactured by Nippon Steel Chemical)
A comparative electrorheological fluid composition (hereinafter referred to as comparative fluid composition (3)) was prepared by mixing and dispersing it in 70 g. } was obtained.

Example 10 Each of the fluid compositions (I) to (9) and comparative fluid compositions (I) to (3) obtained in Examples 1 to 9 and Comparative Examples 1 to 3 was placed in a double cylinder with a coaxial electric field. Place it in a rotational viscometer and check the inner/outer gap]. ．． Measure the shear stress value (initial value) and current density (initial value) when applying an AC external electric field of 4000 V/mm (frequency: 60 Hz) under the conditions of Onm, shear 1, speed 400 s, and temperature 25°C. did. Furthermore, the shear stress value (value after 5 days) and current density (value after 5 days) were measured after continuous operation of the viscometer at 25 ° C. for 5 days with an external electric field of 4000 V / mm applied, The stability of the fluid composition over time was investigated.

The results are shown in Table 1.

Table 1 As is clear from Table 1, the fluid compositions (I) to (9) obtained in the present invention can obtain large shear stress even when a relatively weak electric field is applied, and have stable stability over time. was also excellent.

On the other hand, with comparative fluid composition (I), no significant shear stress was obtained when a relatively weak electric field was applied.

Comparative fluid composition (2) obtained a large shear stress even when a relatively weak electric field was applied, but its stability over time was poor. Furthermore, Comparative Fluid Composition (3) could not obtain a large shear stress when a relatively weak electric field was applied, and its stability over time was poor.

Claims (1)

[Scope of Claims] 1. A composition comprising dispersed phase particles dispersed in an insulating dispersion medium, the dispersed phase particles comprising a vinyl aromatic compound having at least one alkoxy group in the aromatic ring ( A monomer mixture (A) containing a) and a polyvinyl compound (b) as essential components and adding another vinyl compound (c) as necessary.
The sulfonated polymer particles obtained by sulfonating the aromatic rings present in the polymer crosslinked product (I) contain 10 parts by weight or less of water per 100 parts by weight of the particles, and the aromatic A monomer mixture of a vinyl aromatic compound (a) having at least one alkoxy group in the group ring (
An electrorheological fluid composition characterized in that the proportion in A) is 5.0 mol% or more. 2. The electrorheological fluid composition according to claim 1, wherein the particle size of the dispersed phase particles is in the range of 0.1 to 100 μm. 3. The electrorheological fluid composition according to claim 1 or 2, wherein the ratio of the dispersed phase particles to the insulating dispersion medium is in the range of 50 to 500 parts by weight to 100 parts by weight of the former.