JPH0235933A - Electroviscous fluid composition - Google Patents

Abstract

PURPOSE:To generate a great shearing stress by application of weak electric fields by dispersing particles of polymer having specific number of cationic dissociation radicals and anionic dissociation radicals in an electrical insulating dispersion medium to prepare a fluid composition. CONSTITUTION:Unsaturated monomers containing anionic dissociation radicals such as sulfonic acids, etc., and unsaturated monomers containing cationic dissociation radicals such as amino radicals, etc., together with other monomers capable of polymerizing when required, are caused to be copolymerized to produce polymers or crosslinked substances, which thereafter are granulated. The particles thus obtained contain respectively 0.5mg equivalent/g or more of cationic dissociation radicals and anionic dissociation radicals, wherein number of anionic dissociation radicals is 10-1000 per 100 of cationic dissociation radicals. The particles obtained are dispersed in an electric insulating dispersion medium for preparation of electroviscous fluid compositions.

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 by applying a change in electric field and has excellent stability over time of the generated shear stress.

(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 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, dampers, etc.
Applications to brakes, shock absorbers, actuators, etc. are being attempted.

Conventionally, electrorheological fluids include solid particles such as cellulose, starch, soybean protein, polystyrene ion exchange resin, and crosslinked polyacrylic acid salts dispersed in insulating oil such as silicone oil, diphenyl chloride, and transformer oil. What caused it is known.

However, electrorheological fluids using cellulose, starch, or soybean casein as the dispersed phase have a problem in that the induced shear stress is small, and electrorheological fluids using polystyrene-based ion exchange resin as the dispersed phase have poor stability over time. There was a problem that there was a lack of Furthermore, an electrorheological fluid using a crosslinked polyacrylate as a dispersed phase has a problem in that a practically sufficient shear stress cannot be induced simply by applying a relatively weak electric field.

Furthermore, when a DC electric field is applied to an electrorheological fluid composition using the apparatus shown in FIG. 1, when a fluid composition containing only anionic dissociative groups in the dispersed phase particles is used, No significant shear stress was induced when the inner cylinder was used as the cathode and the outer cylinder was used as the anode, and conversely, when a fluid composition containing only cationic dissociable groups in the dispersed phase particles was used, the inner cylinder was used as the anode and the outer cylinder was used as the anode. There was a problem in that no significant shear stress was induced when the cylinder was used as a cathode.

(Problem to be solved by the invention) The present invention solves the above problems.

Therefore, an object of the present invention is to generate a large shear stress even by applying a relatively weak electric field, and to maintain it for a long period of time, which is excellent in stability over time. The object of the present invention is to provide an electrorheological fluid composition in which induced shear stress is not affected.

(Means and effects for solving the problems) The present invention provides particles having 0.5 Rg equivalent m/g or more each of cationic dissociative groups and anionic dissociative groups, and with respect to 100 cationic dissociative groups. The present invention relates to an electrorheological fluid composition in which particles of a polymer and/or a crosslinked product thereof having an anionic dissociation M number in the range of 10 to 1000 are dispersed in an insulating dispersion medium.

As a method for obtaining particles of the polymer and/or its crosslinked product used in the present invention, for example, A polymer obtained by copolymerizing an unsaturated monomer (B) containing a cationic dissociative group such as a group or a quaternary ammonium group with other polymerizable monomers ([1) as required] Method of granulating the polymer, ■ Adding a polymer or monomer of monomer (B) to a polymer of monomer (A) or a copolymer of monomer (^) and monomer (D) (8) and a monomer (a copolymer with DJ or a polymer of polymerizable aziridine compound (C)) are mixed and granulated to contain both cationic dissociative groups and anionic dissociative groups in the particles. Method, ■ Monomer (A)
of the polymer or monomer (A) and monomer (DJ) by reacting a part of the anionic dissociative group contained in the copolymer with the aziridine compound (C), etc. A method of granulating a polymer obtained by converting a part of anionic dissociative groups into cationic dissociative groups, (1) a polymer of monomer (8) or monomer (8) and monomer ( A part of the cationic dissociative group contained in the copolymer with D) or an aziridine compound (
A part of the imino groups contained in the polymer of C) is converted into a monomer (
A) Cationic decomposition in the polymer by reacting with etc. I! A method of granulating a polymer obtained by converting a part of one group into an anionic dissociative group, (1) monomer (A) and monomer (0
) A method of granulating a polymer obtained by converting a nonionic functional group contained in a copolymer with a cationic dissociable group, ■ Monomer (8) and monomer (D) Examples include a method of granulating a polymer obtained by converting a nonionic functional group contained in a copolymer with an anionic dissociable group into an anionic dissociable group.

Note that polymer granulation here refers to polymer and/or
The process involves turning the crosslinked product into powder particles with a particle size fine enough to be dispersed in an insulating dispersion medium, such as pulverizing a lump of the polymer and/or its crosslinked product, or
Alternatively, it may include fixing fine powder of the crosslinked product using a binder, if necessary, to form uniform granules. Further, emulsion polymerization or suspension polymerization may be employed during monomer polymerization to perform granulation at the same time as y4 production of the polymer and/or its crosslinked product.

Furthermore, when mixing the polymers in the method of It is also possible to bond both polymers.

Examples of the monomer (A) containing an anionic dissociative group that can be used in the present invention include vinyl sulfonic acid,
Allylsulfonic acid, methallylsulfonic acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl (meth)acrylate, 3-
Sulfopropyl (meth)acrylate, 1-sulfopropan-2-yl (meth)acrylate, 2-sulfopropyl (meth)acrylate, 1-sulfobutan-2-yl (meth)acrylate, 2-sulfobutyl (meth)acrylate, 3 - Sulfonic acids containing polymerizable unsaturated groups such as sulfobutan-2-yl (meth)acrylate; carboxylic acids containing polymerizable unsaturated groups such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, etc. Acids and/or their alkali metal salts such as lithium, sodium and potassium, alkaline earth metal salts such as calcium and magnesium, other metal salts such as zinc, aluminum and copper, ammonium salts, Ariiso amine salts,
Examples include salts such as pyridinium salts and guanidium salts, and one or more of them can be used.

Examples of the monomer (B) containing a cationic dissociative group that can be used in the present invention include 2-aminoethyl (
meth)acrylate, 2-aminoethyl (meth)acrylamide, 2-[methylaminocoethyl (meth)acrylate, 2-[ethylaminocoethyl (meth)acrylate, 2-[N.

N-dimethylaminocoethyl (meth)acrylate, 2
- [N,N-diethylaminoconityl (meth)acrylate, 2-[N,N-diethylaminoconityl (meth)acrylamide, 3-EN.

N-diethylamino 1propyl (meth)acrylate,
3-[N,N-diethylaminocopropyl (meth)acrylamide, 3-[N,N-dipropylaminocopropyl (meth)acrylate, 3-EN,N-dipropylaminocopropyl (meth)acrylamide, 3- [N, N
-dimethylaminocopropyl (meth)acrylate, 3
-[N,N-dimethylaminocopropyl (meth)acrylamide, 3-[N,N-dimethylaminocobutyl (meth)acrylate, 3-[N,N-dimethylaminocobutyl (meth)acrylamide, tris[2- (meth)acryloyloxyethyl]amine and other unsaturated monomers containing a 7-mino group, and their hydrochlorides, sulfates, bromates, iodates, fluorates, nitrates, cyanates, thiocyanates, Phosphate, borate, carbonate, sulfite, hypochlorite, perchlorate, acetate, formate, propionate, benzoate, p-toluenesulfonic acid/benzenesulfonic acid/methane Places such as sulfonic acid salts such as sulfonic acid, ethanesulfonic acid, isethionic acid, dodecylbenzenesulfonic acid; and 2-[(meth)acryloyloxy]ethyltrimethylammonium chloride, 2-[(
meth)acryloyloxyconityltrimethylammonium bromide, 2-[(meth)acryloyloxy]
Quaternary ammonium group-containing unsaturated monomers such as ethyltrimethylammonium iodite and 2-[(meth)acryloyloxy]ethyldimethylphenylammonium chloride can be mentioned, and one or more of them are used. be able to.

Aziridine compound (C) that can be used in the present invention
For example, ethyleneimine, propyleneimine,
Butyleneimine, N- and droxyethylethyleneimine, N-cyanoethylethyleneimine, N-methylethyleneimine, N-ethylethyleneimine, N-phenylethyleneimine, N-acetylethyleneimine, N-methacryloylaziridine, β-aziridine Lysinyl methyl brobionate, β-aziridinylethyl methacrylate, hexamethylene-bis-1,6-N, N'-diethyleneurea, diphenylmethane-bis-4,4'N, N'-
Examples include diethylene urea, 2,2-bishydroxymethylbutanol-tris[3-(1-aziridinyl)propionate, etc., and one or more types thereof can be used.

Monomers that can be used in the present invention (as DJ,
For example, water-soluble unsaturated monomers such as (meth)acrylamide, (meth)acrylonitrile, vinyl acetate, etc.: hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, etc. ) Acrylate, polybutylene glycol mono(meth)
Acrylate, methoxypolyethylene glycol mono(
meth)acrylate, methoxypolypropylene glycol mono(meth)acrylate, methoxypolybutylene glycol mono(meth)acrylate, ethoxypolyethylene glycol mono(meth)acrylate, ethoxypolypropylene glycol mono(meth)acrylate, ethoxypolybutylene glycol mono(meth)acrylate , methoxypolyethylene glycol/polypropylene glycol mono(meth)acrylate, phenoxypolyethylene glycol mono(meth)acrylate, benzyloxypolyethylene glycol mono(meth)acrylate, methyl(meth)acrylate, ethyl(meth)acrylate, butyl(meth)acrylate, etc. (meta)
Examples include acrylic esters; and hydrophobic unsaturated monospecies such as styrene, vinyl chloride, butadiene, isoprene, ethylene, and propylene, and one or more of these can be used.

It is necessary that the particles of the polymer and/or its crosslinked product used in the present invention contain cationic dissociative groups and anionic dissociative groups, each of 1t/Q or more per 0.5 rftg. The cationic dissociative group and anionic dissociative group are each 0.5 IItg! ! /Q, the shear path force will not become sufficiently large when an electric field change is applied to the resulting electrorheological fluid composition.

Moreover, even if either the cationic dissociative group or the anionic dissociative group is contained in 1/0.5η/Q or more, the other one is included in 0.5η/1! /g, when a DC electric field is applied to the resulting electrorheological fluid composition, the induced shear path force is greatly affected by the direction of the electric field, and no significant shear path force may be observed.

The ratio of the number of cationic dissociative groups to the number of anionic dissociable groups contained in the particles of the polymer and/or its crosslinked product used in the present invention is 100 to the number of cationic dissociable groups. It is necessary that the number of anionic dissociative groups is in the range of 10 to 1000.

When the number of anionic dissociative groups is less than 10 compared to 100 cationic dissociable groups, when a relatively weak electric field is applied, especially when the inner cylinder in Figure 1 is used as the anode and the outer cylinder is used as the cathode. In fact, sufficient shear path force cannot be obtained, and the induced shear path force tends to attenuate over time. Also,
When the number of anionic dissociative groups exceeds 1000 compared to 100 cationic dissociable groups, when a relatively weak electric field is applied, especially when the inner tube in Figure 1 is used as the cathode and the outer tube is used as the anode. In fact, sufficient shear path force cannot be obtained, and the induced shear path force tends to attenuate over time.

The polymer used in the present invention may be a crosslinked product having a crosslinked structure. Rather, it is preferable to use a crosslinked polymer as the polymer, since this improves the stability over time of the resulting electrorheological fluid composition. In order to obtain such a crosslinked product, a crosslinking agent may be mixed into the monomer components and then polymerized, or the polymer may be reacted with a crosslinking agent.

Examples of these crosslinking agents include divinylbenzene, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, and polyprolene glycol di(meth)acrylate.
meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)
Compounds having two or more ethylenically unsaturated groups in one molecule such as acrylate, pentaerythritol di(meth)acrylate, N,N-methylenebisacrylamide, triallyl isocyanurate, trimethylolpropane di7lyl ether; ethylene glycol, diethylene glycol , triethylene glycol, polyethylene glycol, glycerin, polyglycerin, propylene glycol, jetanolamine, triethanolamine, polypropylene glycol, polyvinyl alcohol, pentaerythritol, sorbitol, turdotan, glucose, mannitol, mannitan, sucrose, glucose Polyhydric alcohols such as ethylene glycol diglycidyl ether, glycerin diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanethiol diglycidyl ether, trimethylolpropane diglycidyl ether,
Examples include polyepoxy compounds such as trimethylolpropane triglycidyl ether and glycerin triglycidyl ether, and one or more of these can be used. When using a polyhydric alcohol as a crosslinking agent, heat treatment is preferably performed at 150°C to 250°C, and when using a polyepoxy compound, heat treatment is preferably performed at 50°C to 250°C.

The polymerization method for obtaining the polymer used in the present invention may be any conventionally known method, such as a method using a radical polymerization catalyst and a method of irradiating with radiation, electron beams, ultraviolet rays, etc. Examples of radical polymerization catalysts include hydrogen peroxide, peroxides such as benzoyl peroxide and cumene hydroperoxide, azo compounds such as azobisisobutyronitrile, ammonium persulfate,
Too late! Radical generators such as peroxide salts such as potassium I-acid, and redox initiators in combination with reducing agents such as sodium bisulfite, L-ascorbic acid, and ferrous salts are used. As the polymerization solvent, for example, water, methanol, ethanol, acetone, dimethylformamide, dimethyl sulfoxide, hexane, cyclohexane, xylene, toluene, benzene, etc., and mixtures thereof can be used. The temperature during polymerization varies depending on the type of catalyst used, but a relatively low temperature is preferable because the molecular weight of the polymer increases. However, in order to complete the polymerization, the temperature is preferably within the range of 20°C or more and 100°C or less.

There is no particular limit to the monomer concentration in the polymerization system, but considering ease of control of the polymerization reaction, yield, and economic efficiency, it should be between 20 and 80%.
Preferably, it is in the range of % by weight. Various forms of polymerization can be adopted, such as suspension polymerization, cast polymerization, and a method in which a gel-like hydrous polymer is polymerized while being fragmented by the shear force of a double-arm kneader (Japanese Patent Laid-Open No. 57-34101
). Among these, suspension polymerization, such as a method in which an aqueous monomer solution is suspended in a hydrophobic organic solvent and then polymerized, is particularly preferred since spherical fine particles can be obtained.

There are no particular restrictions on the particle size and shape of the polymer and/or its crosslinked product used in the present invention, but the particle size is 0.
．． The diameter is preferably 1 to 500 μm, and the shape is preferably spherical. If the particle size is out of the above range or the shape is amorphous, the shear path force may not become sufficiently large when an electric field change is applied to the resulting electrorheological fluid composition.

The insulating dispersion medium used in the present invention is 109Ωα
There is no particular restriction as long as it is an electrically insulating liquid having an electrical resistance of at least Low polymers of fluorides such as Demnam@ (manufactured by Daikin Industries, Ltd.) Esters such as dioctyl diphthalate, trioctyl trimellitate, isodecyl trimellitate, dibutyl sebacate; liquid paraffin, petroleum ether, petroleum benzine, Hydrocarbons such as xylene, benzene, toluene, and tetralin; examples include silicone oil, trans oil, and mixtures thereof.

In the present invention, the ratio of the particles of the polymer and/or its crosslinked product to the insulating dispersion medium is not particularly limited, but the ratio of the particles of the polymer and/or its crosslinked product to the insulating dispersion W, 100 severely affected areas is preferably in the range of 5 to 400 parts by weight. If the suspension of particles of the polymer and/or its crosslinked product is less than 5 parts by weight, the shear stress may not be sufficiently large when an electric field change is applied to the resulting electrorheological fluid composition; If it exceeds this, the fluidity of the resulting composition itself may decrease, making it difficult to use it as an electrorheological fluid.

The reason why the electrorheological fluid composition of the present invention exhibits a remarkable Winslow effect is not clear, but the presence of a small amount of water in the particles of the polymer and/or its crosslinked product in the composition causes a change in the electric field. It is thought that large shear stress is induced when However, the water content in the particles of the polymer and/or its crosslinked product in the present invention is preferably 20 weight percent or less. 20% water by weight
If it exceeds this, particles of the polymer and/or its crosslinked product may adhere to each other, or the shear stress may not become large when an electric field change is applied.

In the present invention, in order to improve the dispersibility of particles of a polymer and/or its crosslinked product in an insulating dispersion medium, to adjust the viscosity of an electrorheological fluid composition, or to improve shear stress, a surfactant, a polymer dispersion, etc. Various additives such as thickeners and polymeric thickeners can be added.

(Effect of the invention) When the performance of an electrorheological fluid composition is measured by applying a DC electric field using a coaxial double cylinder rotational viscometer as shown in FIG. When using a fluid composition containing only dissociative groups, it was not possible to obtain significant shear stress when the inner tube was used as a cathode and the outer tube was used as an anode. When using a fluid composition containing this material, no significant shear stress can be obtained when the inner cylinder is used as an anode and the outer cylinder is used as a cathode. However, the electrorheological fluid composition having a specific ratio of cationic dissociative groups and anionic dissociative groups in the dispersed phase particles of the present invention can be used regardless of the direction of the DC electric field and when a relatively weak electric field is applied. It is possible to obtain a practically sufficient shear stress even at a certain time, and the shear stress that is generated has excellent stability over time.

Further, the electrorheological fluid composition of the present invention can obtain a large shear stress even when an external AC electric field is applied using an AC power source, and also has excellent stability over time of the generated shear stress. .

Therefore, the electrorheological fluid composition of the present invention can respond to any external electric field and can be effectively used in a wide range of fields such as clutches, dampers, brakes, shock absorbers, and actuators.

(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.

Example 1 11 cylindrical seprabs, 47.0a (0.5 mol) of sodium acrylate in a Le flask, 2-[methacryloyloxy]ethyltrimethylammonium chloride 10
3.8 (7 (0,5 mol'), N,N' methylenebisacrylamide 0.75a (0,005 mol) and water 35
4 g was charged and stirred to uniformly dissolve. After purging with nitrogen, heat to 40°C in a hot water bath and add 10% ammonium persulfate aqueous solution 1. Oq and 1% L-ascorbic acid aqueous solution 0
．． 5a was added and stirring was stopped to allow polymerization. After the start of polymerization, heat was generated and the temperature rose to 68°C within 30 minutes. After confirming that the temperature of the polymerization system had begun to drop, the water bath was raised to 90°C and heated for an additional hour.

The obtained hydrogel of the polymer was divided into small pieces, dried in a hot air drying machine at 110°C for 8 hours, crushed and classified to obtain particles with a particle size of 5.
Polymer particles (1) (cationic dissociative group density: 3.3 μm/i
1/[7, anionic dissociative group density: 3.3 ■equivalent/CI
). ) was obtained.

After drying 30 g of the obtained polymer particles (1) at 110° C. for 3 hours, the mixture was left in a room at a temperature of 20° C. and a relative humidity of 60% for 1 hour to absorb moisture, and then mixed and dispersed in 70 g of bromobenzene. An electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (1)) was obtained.

Example 2 77.7% of methacrylic acid was added to 11 cylindrical separable flasks.
40 (0.9 mol), 12.9 g (0.1 mol) of 2-aminoethyl methacrylate, and 168 Q of water were charged and stirred to uniformly dissolve, and then polymerized in the same manner as in Example 1.

After dividing the obtained polymer hydrogel into small pieces, it was heated at 80°C for 3
Dry under reduced pressure for hours, crush and classify, particle size 20-50μ
m polymer particles (hereinafter referred to as polymer particles (2) (cationic dissociative group density: 1.1η equivalent ffi/g, anionic dissociative group density: 10.Oη equivalent ffi/Cl). ) was obtained.

After drying 20 g of the obtained polymer particles (2) at 110°C for 3 hours, they were left in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture. 8
They were mixed and dispersed in OQ to obtain an electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (2)).

Example 3 1.1 j of n-hexane was placed in 21 four-necked flasks equipped with a stirrer, reflux condenser, dropping funnel and nitrogen gas inlet tube.
and sorbitan monostear 1-9. After adding and dissolving OQ, the atmosphere was replaced with nitrogen.

Into the dropping funnel, 61.3 g (0.25 mol) of potassium 2-acrylamido-2-methylpropanesulfonate, 2-
[methacryloyloxy]ethyltrimethylammonium bromide 63.0Q (0.25 mol), N, N'
- 1.2 g (0,008 mol) of methylenebisacrylamide, 293 g of water and 0.25 g of potassium perylIIM
After adding and dissolving the solution, nitrogen gas was blown in to remove oxygen present in the aqueous solution. Next, the contents of the dropping funnel were added to the neck flask and dispersed, and the temperature of the polymerization system was raised to 60°C in a hot water bath while introducing a slight amount of nitrogen gas.
The polymerization reaction was continued for 3 hours while maintaining the temperature at ~65°C.

Thereafter, n-hexane was distilled off under reduced pressure, and the remaining hydrogel of the crosslinked polymer was dried under reduced pressure at 90°C for 3 hours, and then classified into particles of the crosslinked polymer with a particle size of 50 to 100 μm. (Hereinafter, this will be referred to as polymer particle (3) (cationic dissociative group density: 2. OItg equivalent/g, anionic dissociative group density: 2.
．． 0Rg win! /q). ) was obtained.

After drying the obtained polymer particles (3125 g at 110°C for 3 hours, leaving them in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture, trioctyl trimellitate 25Q
and 50q of bromobenzene to obtain an electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (3)).

Example 4 43.20 (0.2 mol) of the sodium salt of 2-sulfoethyl methacrylate was placed in 11 cylindrical separable flasks.
, acrylic acid 3.6G (0.05 mol), calcium acrylate 9.1o (0.05 mol), hydrochloride of 2-[N,N-dimethylamine]ethyl acrylate 125.7
g (0.7 mol) and 272 q of water were charged, stirred to uniformly dissolve, and then polymerized in the same manner as in Example 1.

The hydrogel of the obtained polymer was finely divided and incubated at 80°C for 30 minutes.
Dry under reduced pressure for hours, crush and classify, particle size 100-20
0 μm polymer particles (hereinafter referred to as polymer particles (4)
(Cationic dissociative group density: 3.9η equivalent M/g, anionic dissociative group density: 21.9η equivalent M/l) was obtained.

After drying 30 g of the obtained polymer particles (4) at 110° C. for 3 hours, they were left in a room at a temperature of 20” C1 and a relative humidity of 60% for 1 hour to absorb moisture, and then 35 g of bromobenzene and 1.2.
4-)-Lichlorobenzene 35Q mixed in a mixed solvent.
The electrorheological fluid composition C of the present invention is hereinafter referred to as fluid composition (4). ) was obtained.

Example 5 360 q of water was charged into a 21 four-bottle flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a nitrogen gas introduction tube, and while stirring, the inside of the flask was purged with nitrogen and heated to 90°C. Next, while introducing a slight amount of nitrogen gas, sodium acrylate 100.0Q (1.1 mol) and acrylic M! 50
(0.7 mol) and a monomer aqueous solution consisting of 210 g of water and 30 g of a 10% ammonium persulfate aqueous solution were each added over 2 hours from the point of addition. After the addition was completed, the mixture was allowed to cool to obtain a 20% aqueous solution of the polymer (hereinafter referred to as aqueous polymer solution (1)).

Example 6 100 Q of water was charged into an 11 four-bottle flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a nitrogen gas introduction tube, and while stirring, the inside of the flask was purged with nitrogen and heated to 90°C. Next, while slightly introducing nitrogen gas, a monomer aqueous solution consisting of 50.0Q (0.24 mol) of 2-[methacryloyloxy]ethyltrimethylammonium chloride and 90q of water and 10% of a 10% ammonium per'acid aqueous solution were added.
Q and each were added from the dropping funnel over a period of 2 hours.

After the addition was completed, the mixture was allowed to cool to obtain a 20% aqueous solution of the polymer (hereinafter referred to as aqueous polymer solution (2)).

Example 7 100Q of water was charged into a four-hole flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a nitrogen gas inlet tube, and while stirring, the inside of the flask was purged with nitrogen and heated to 90°C.

Then, while introducing a slight amount of nitrogen gas, 50 g (0.39 mol) of 2-aminoethyl methacrylate and 90 g of water were added.
A monomer aqueous solution consisting of 9 and a 10% ammonium persulfate aqueous solution 10σ were each added over 2 hours from the point of addition. After the addition was completed, the mixture was allowed to cool to obtain a 20% aqueous solution of the polymer (hereinafter referred to as polymer aqueous solution (3)).

Example 8 Polymer aqueous solution (1
) 200c> and 200g of polymer aqueous solution (2),
A polyion complex was formed. Next, the inside of the flask was heated at 90° C. for 1 hour in a hot water bath.

Thereafter, most of the water was distilled off under reduced pressure, and the remaining hydrogel of the polymer was dried under reduced pressure at 90°C for 3 hours, then crushed and classified to produce polymer particles (hereinafter referred to as Polymer particles (5) (cationic dissociative group density: 2.4
η equivalent weight/g, anionic dissociative group density = 5.9 ■ equivalent weight/g
). ) was obtained.

After drying 15 g of the obtained polymer particles (5) at 110°C for 3 hours, they were left in a room at a temperature of 20'C1 and a relative humidity of 60% for 1 hour to absorb moisture, and then mixed in bromobenzene 850.
The mixture was dispersed to obtain an electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (5)).

Example 9 Polymer aqueous solution (1) was placed in 11 cylindrical separable flasks.
100Q, polymer aqueous solution (3) 250Cl and N, N'
-methylenebisacrylamide 0.92Q (0,00
6 mol) was added and stirred to uniformly dissolve it. Next, the inside of the flask was heated at 90° C. for 1 hour in a hot water bath.

Thereafter, most of the water was distilled off under reduced pressure, and the remaining polymer hydrogel was dried under reduced pressure at 90°C for 3 hours, then crushed and classified to form crosslinked polymer particles with a particle size of 10 to 50 μm. (Hereinafter, this will be referred to as polymer particle (6) (cationic dissociative group density: 5
．． 51 ftg equivalent m/Q, anionic dissociative group density: 3.3
It is called IItg equivalent/G). ) was obtained.

After drying 20G of the obtained polymer particles (6) at 110°C for 3 hours, they were left in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture, and then bromobenzene 309 and 1.2.4
- The electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (6)) was obtained by mixing and dispersing it in a mixed solvent of 50 °C of trichlorobenzene.

Example 10 Polymer aqueous solution (1) in 11 cylindrical separable flasks
1000. Polyethyleneimine (Nippon Shokubai Chemical Industry (I)
Made by Ebomin'l! 200 g of a 30% aqueous solution of 'P-1000) and 0.3 (J (0,002 mol)) of N,N'-methylenebisacrylamide were charged and stirred to dissolve uniformly.Then, the inside of the flask was placed in a hot water bath. 90℃
It was heated for 1 hour.

Thereafter, most of the water was distilled off under reduced pressure, and the remaining polymer hydrogel was dried under reduced pressure at 90°C for 3 hours, then crushed and classified to form crosslinked polymer particles with a particle size of 50 to 150 μm. Hereinafter, this will be described as polymer particles (7) (m-ionic mfliM-densified
: 17.4Itg per II/Cl, anionic dissociative group density=2.9■equivalent/l. ) was obtained.

After drying 35 g of the obtained polymer particles (7) at 110°C for 3 hours, they were left in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture, and then 65 g of trioctyl trimellitate was dried.
The electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (7)) was obtained by mixing and dispersing the fluid composition.

Example 11 Aqueous polymer solution (1) at 300 °C was charged into 11 cylindrical separable flasks equipped with a stirrer, a reflux condenser, a dropping funnel, and a nitrogen gas introduction tube, and the inside of the flask was replaced with nitrogen while stirring to create a nitrogen atmosphere. The temperature of the reaction system was maintained at 20°C.

Ethyleneimine 7.2o (0,1
7 mol) was added dropwise over 1 hour, and after the addition, the mixture was heated at 80°C for 3 hours. The reaction rate of ethyleneimine to the polymer was measured by colloid titration and was found to be 80%.

Next, most of the water in the aqueous polymer solution was distilled off under reduced pressure, and the remaining water-containing gel was dried under reduced pressure at 90°C for 3 hours, and then pulverized.
The polymer particles with a particle diameter of 50 to 100 μm (hereinafter referred to as polymer particles (8) (cationic dissociative group density:
2. oη equivalent/g, anionic dissociative group density: 8.7Iy
J to 1n/Q>. ) was obtained.

The obtained polymer particles (8) 30Q were dried at 110'C for 3 hours, left in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture, and then mixed in 70g of bromobenzene.
The electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (8)) was prepared by dispersing the electrorheological fluid composition (19).

Example 12 Polyethyleneimine (manufactured by Nippon Shokubai Chemical Co., Ltd., Evomin@P-100) was placed in 11 cylindrical separable flasks equipped with a stirrer, a reflux condenser, a dropping funnel, and a nitrogen gas introduction tube.
400 q of a 30% aqueous solution of 0) was charged, and the inside of the flask was purged with nitrogen while stirring, and maintained at 20° C. under a nitrogen atmosphere. Acrylic M72q (1.0 mol) was added dropwise thereto from a dropping funnel over a period of 1 hour, and after the addition, the mixture was heated at 80° C. for 3 hours. The reaction rate of acrylic acid to polyethyleneimine was measured by colloid titration and was found to be 100%.

Next, most of the water in the aqueous polymer solution was distilled off under reduced pressure, and the remaining water-containing gel was dried under reduced pressure at 90°C for 3 hours, and then pulverized.
After classification, polymer particles with a particle size of 100 to 250 μm (
Hereinafter, this will be described as polymer particle (9) (cationic dissociative group density: 9.3η equivalent/g, anionic dissociative group density: 5.2I
! It is called gtoffi/Q). ) was obtained.

The obtained polymer particles (9125 g) were dried at 110°C for 3 hours, left in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture, and then dissolved in 1.2.4-trichlorobenzeschiff 5Q. were mixed and dispersed to obtain an electrorheological fluid composition of the present invention (hereinafter referred to as fluid composition (9)).

Comparative Example 1 70.50 (0.75 mol) of sodium acrylate and 18.5 mol of acrylic acid were placed in a 500-mm cylindrical separable flask.
0q (0,25 mol), N,N'-methylenebisacrylamide 0.092o (0,0006 mol) and water 1
After charging 65 g and stirring to uniformly dissolve it, polymerization was carried out in the same manner as in Example 1.

The obtained hydrogel of the polymer was divided into small pieces, dried at 150°C for 3 hours, crushed and classified to particles with a particle size of 50 to 100 μm.
Particles of polymer crosslinked product of
). ) was obtained.

After drying 30 g of the obtained comparative polymer particles (1) at 110°C for 3 hours, they were left in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture, and then mixed and dispersed in bromobenzene 709. A comparative electrorheological fluid composition (hereinafter referred to as comparative fluid composition (1)) was obtained.

Comparative Example 2 In a 500 d cylindrical separable flask were placed 103.8 g (0.5 mol) of 2-[methacryloyloxy]ethyltrimethylammonium chloride, 0.17 g (0.001 mol) of ethylene glycol diacrylate, and 19 g of water.
After charging 3 g and stirring to dissolve uniformly, Example 1
It was polymerized in the same way.

After dividing the obtained polymer hydrogel into small pieces, it was heated at 80°C for 3
Dry under reduced pressure for an hour, crush and classify to obtain particles with a particle size of 50 to 100.
Particles of a crosslinked polymer having a diameter of 11 μm (hereinafter referred to as Comparative Polymer Particles (2) (density of 11 ionic dissociative groups: 4.8 my per Wi/Q)) were obtained.

After drying 30 g of the obtained comparative polymer particles (2) at 110°C for 3 hours, they were left in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture, and then mixed and dispersed in Bromobenge Schiff 0q. A comparative electrorheological fluid composition (hereinafter referred to as comparative fluid composition (2)) was obtained.

Comparative Example 3 Amberlite ■IR-120 days (Organo VT7) which is a sodium polystyrene sulfonate type ion exchange resin
J product) was dried at 150°C for 3 hours, then crushed and classified to obtain polymer particles (hereinafter referred to as comparative polymer particles (3)) having a particle size of 50 to 100 μm (anionic dissociative group density: 4. 4■
131/Q>. ) was obtained.

The obtained comparative polymer particles (3) 300 were dried at 110°C for 3 hours, left in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture, and then mixed and dispersed in bromobenzene 700. A comparative electrorheological fluid composition (hereinafter referred to as comparative fluid composition (3)) was obtained.

Comparative Example 4 Amberlite @ IRA-400 (manufactured by Organo ■), which is a polystyrene-based quaternary ammonium type ion exchange resin, was dried under reduced pressure at 80°C for 3 hours, then crushed and classified to obtain a polymer with a particle size of 50 to 100 μm. particles (hereinafter referred to as polymer particles (4) (cationic dissociative group density: 3.7Rg)
equivalent weight/g). ) was obtained.

The obtained comparative polymer particles (4) 30G were dried at 110°C for 3 hours, left in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture, and then mixed and dispersed in Bromobenge Schiff 0Q. A comparative electrorheological fluid composition (hereinafter referred to as comparative fluid composition (4)) was obtained.

Comparative Example 5 4.7 g (0.05 mol) of sodium acrylate and 10.4 g of 2-[methacryloyloxy]ethyltrimethylammonium chloride were placed in a 500-mm separable flask.
(7 (,0,05 mol), acrylamide 135.7
Q (1.91 mol) and 280 g of water were charged, stirred to uniformly dissolve, and then polymerized in the same manner as in Example 1.

After dividing the obtained polymer hydrogel into small pieces, it was heated at 80°C for 3
After drying under reduced pressure for an hour, it is crushed and classified to a particle size of 50 to 100.
μm polymer particles (hereinafter, this will be compared with polymer particles <5
1 (Cationic dissociative group vacancy: 0.33η L anionic dissociative group density = 0.33η/g). ) was obtained.

The obtained comparative polymer particles (5) 30G were dried at 110°C for 3 hours, left in a room at a temperature of 20°C and a relative humidity of 60% for 1 hour to absorb moisture, and then mixed and dispersed in Bromobenge Schiff 0Q. A comparative electrorheological fluid composition (hereinafter referred to as comparative fluid composition (5)) was obtained.

Examples 13 to 30 and Comparative Examples 6 to 15 Each of the electrorheological fluid compositions shown in Tables 1 and 2 was placed in a double cylindrical rotational viscometer with an electric field as shown in FIG. Direct current external electric field 1 at a speed of 400 S”
The shear stress was measured when 500 V/s or 3000 V/rtm was applied. In addition, the shear stress was measured after the viscometer was operated for three consecutive days with an external electric field applied to examine stability over time.

Table 1 shows the measurement results when the inner cylinder of the viscometer was used as the anode and the outer cylinder as the cathode, and Table 2 shows the measurement results when the inner cylinder was used as the cathode and the outer cylinder was used as the anode.

No. No. table

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of a double cylindrical rotational viscometer with a direct current electric field used to measure the performance of an electrorheological fluid in an embodiment of the present invention. 1: Inner tube 2: Outer tube 3: DC power source 4: Electrorheological fluid 5: Viscometer body

Claims (1)

[Scope of Claims] 1. Particles each have 0.5 mg equivalent/g or more of cationic dissociative groups and anionic dissociative groups, and the number of anionic dissociative groups is 10 to 100 per 100 cationic dissociable groups. 10
1. An electrorheological fluid composition comprising particles of a polymer and/or a crosslinked product thereof in the range of 0.00 to 0.00, dispersed in an insulating dispersion medium. 2. The particle size of the polymer and/or its crosslinked product is 0.1
The electrorheological fluid composition of claim 1, wherein the electrorheological fluid composition is in the range of ~500 [mu]m. 3. The ratio of the particles of the polymer and/or its crosslinked product to the insulating dispersion medium is 5 to 40 parts by weight to 100 parts by weight of the latter.
The electrorheological fluid composition according to claim 1 or 2, wherein the electrorheological fluid composition is in the range of 0 parts by weight.