JP2008013608A - Aqueous emulsified dispersion of butyl rubber and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aqueous emulsified dispersion of a butyl rubber excellent in particularly insulating properties that is suitable for a vibration-damping material, an adhesive, a pressure-sensitive adhesive, a coating, a coating material or the like, and its manufacturing method. <P>SOLUTION: The aqueous emulsified dispersion comprises a butyl rubber emulsified and dispersed using an emulsifier comprising a nonionic emulsifier, and is manufactured by mixing a rubber solution, obtained by dissolving the butyl rubber in an organic solvent, with the emulsifier comprising at least one nonionic emulsifier, stirring the mixture to emulsify the rubber solution and subsequently diluting the emulsified rubber solution with water and then distilling out the organic solvent. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an aqueous emulsion dispersion of butyl rubber. More specifically, it is an aqueous emulsion dispersion excellent in storage stability that maintains the excellent insulating properties, vibration damping properties, gas barrier properties, etc. of butyl rubber. For example, vibration damping materials, adhesives, adhesives, paints, coatings The present invention relates to an aqueous emulsified dispersion of butyl rubber that can be suitably used for the production of materials and the like.

  Various methods for obtaining aqueous emulsion dispersions of butyl rubber have been proposed to date, but no examples of industrial production and supply of aqueous emulsion dispersions with excellent storage stability have been found, on an industrial scale. Production in is not carried out.

  Regarding the aqueous emulsion dispersion of butyl rubber, for example, JP-A-2-70725 discloses a method of emulsifying an organic solvent solution of butyl rubber in the presence of rubber extender oil and phosphate ester. The added rubber extender oil and phosphoric acid ester remain in the butyl rubber, causing a problem that the vibration damping property and gas barrier property are remarkably lowered.

  Japanese Patent Publication No. 5-63423 discloses a method of kneading butyl rubber and polybutene with a kneader, adding and kneading toluene, and then adding water little by little to obtain an emulsion. The particle size of the butyl rubber in the resulting emulsion is large, and there is a problem that the rubber component is quickly separated, and JP-A-9-221610 discloses that high shear is applied to stearic acid, polyisobutylene and water. Shows a method for obtaining a polyisobutylene emulsion, but in this case as well, the rubber component is quickly separated, and good storage stability cannot be obtained.

  JP-A-11-140250 discloses a heptane solution of a silicon-containing group-terminated isobutylene polymer as a specific example of a method of shear mixing a mixture of an isobutylene polymer and a solvent with water in the presence of an emulsifier. Although a method of emulsifying sodium sulfate in water as an emulsifier has been shown, there is a problem that the emulsion becomes unstable over time.

  Japanese Patent Application Laid-Open No. 2003-321551 discloses a method in which a rubber organic solvent solution is dispersed in a lower alcohol-containing emulsifier aqueous solution, and then the solvent and the lower alcohol are removed by heating under reduced pressure, which enables fine dispersion of rubber. However, since the solvent and the lower alcohol are distilled off simultaneously, when the solvent is reused industrially, a step for separating the solvent and the alcohol is necessary, which is not economically preferable.

In Japanese Patent Publication No. 2-52934, liquid or viscous solid polyisobutylene is emulsified in water using sucrose fatty acid ester, polyoxyethylene sorbitan monofatty acid ester and branched dodecylbenzenesulfonate as an emulsifier. In this method, it is described that polymer polyisobutylene that is solid at room temperature cannot be emulsified, and there is a drawback that only a low-strength polyisobutylene emulsion can be obtained.
JP-A-2-70725 Japanese Patent Publication No. 5-63423 Japanese Patent Laid-Open No. 9-221610 JP-A-11-140250 JP 2003-321551 A Japanese Examined Patent Publication No. 2-52934

  The problems to be solved by the present invention are suitable for vibration damping materials, adhesives, pressure-sensitive adhesives, paints, coating materials, etc., without substantially reducing the insulation properties, vibration damping properties, gas barrier properties, etc. of butyl rubber. Another object of the present invention is to provide a water-based emulsified dispersion of butyl rubber, particularly excellent in insulation, and a method for producing the same.

  As a result of intensive studies in view of such a situation, the inventors further added a mixed aqueous solution of a nonionic emulsifier to a solution composed of butyl rubber and an organic solvent, mixed and emulsified, and diluted with water. By distilling off the organic solvent, it is suitable for damping materials, adhesives, paints, coating materials, etc., without substantially reducing the insulation, damping properties, gas barrier properties, etc. of butyl rubber. The present inventors have found that an aqueous emulsion dispersion of butyl rubber that is excellent in the above-mentioned conditions has been obtained, and the present invention has been achieved.

  That is, the present invention is an aqueous emulsified dispersion of butyl rubber, wherein butyl rubber is emulsified and dispersed with an emulsifier containing at least one nonionic emulsifier.

  In the aqueous emulsified dispersion of butyl rubber of the present invention, the amount of the nonionic emulsifier is preferably 1 to 20 parts by weight with respect to 100 parts by weight of the butyl rubber.

  The present invention also emulsifies the rubber solution by mixing and stirring a rubber solution obtained by dissolving butyl rubber in an organic solvent and an emulsifier containing at least one nonionic emulsifier, and then the emulsification. In the method for producing an aqueous emulsified dispersion of butyl rubber, the organic solvent is distilled off after diluting the rubber solution with water.

  In the method for producing an aqueous emulsion dispersion of butyl rubber according to the present invention, the amount of the nonionic emulsifier is 1 to 20 parts by weight with respect to 100 parts by weight of the butyl rubber, and the solid content after the organic solvent is distilled off Is preferably 40 to 65% by weight.

  In the production method of the present invention, the organic solvent is at least one selected from the group consisting of hexane, isohexane, pentane, cyclohexane, heptane, isooctane, xylene, toluene, benzene, and carbon dioxide in a supercritical state. It is preferable to consist of two.

  The aqueous emulsified dispersion of butyl rubber obtained by the present invention is particularly excellent in insulation and exhibits useful vibration damping properties and gas barrier properties, so that it can be used in automobiles, railways, ships, architecture, industrial machinery, housing equipment, home appliances, It can be suitably used for the production of vibration damping materials, adhesives, adhesive materials, paints, coating materials and the like useful in a wide range of fields such as office equipment and aircraft, and has a great industrial value and is useful.

  Hereinafter, embodiments for carrying out the present invention will be described in detail.

  The present invention includes an aqueous emulsified dispersion of butyl rubber, which is emulsified and dispersed in the presence of an aqueous solution containing at least one nonionic emulsifier selected from the group consisting of nonionic emulsifiers, and a method for producing the same. .

  In the present invention, butyl rubber is butyl rubber (IIR), which is a copolymer of isobutylene and a small amount of isoprene, which are commercially available under the general name “butyl rubber”, and halogenated such as chlorinated butyl rubber and brominated butyl rubber. It means polyisobutylene obtained by polymerizing butyl rubber and isobutylene.

  Examples of commercial products of butyl rubber include “JSR Butyl 065, 268, 365”, “JSR CHLOROBUTYL 1066, 1068”, “JSR BROMOBUTYL 2244, 2255”, etc. of JSR Corporation, and “EXXON BUTY, Exxon BUTYL, Exxon Chemical” 268, 365 "," EXXON CHLOROBUTYL 1066, 1068 "," EXXON BROMOBUTYL 2244, 2255 "and the like.

  In the present invention, an emulsifier is used to emulsify and disperse a solvent solution obtained by dissolving the butyl rubber in an organic solvent.

  As the emulsifier, butyl rubber can be emulsified and dispersed. From the viewpoint of emulsification power and reproducibility of butyl rubber properties after drying of the obtained emulsion, particularly from the viewpoint of insulation, nonionic emulsifiers are the most excellent. Show the effect.

  Examples of nonionic emulsifiers include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl amine ethers, polyoxyethylene fatty acid esters, sorbitan fatty acid esters, and sucrose fatty acid esters. Of these, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers and the like are preferable.

  In the aqueous emulsion dispersion of butyl rubber, the amount of the nonionic emulsifier is preferably 1 to 20 parts, more preferably 3 to 10 parts, with respect to 100 parts (parts by weight) of butyl rubber. If the blending amount falls outside this range, it causes problems in poor emulsification in the manufacturing process and stability after emulsification. If it exceeds this range, the butyl rubber after drying the aqueous dispersion This may cause problems such as loss of physical properties and bleeding out.

  The aqueous emulsion dispersion of butyl rubber is prepared by adding an aqueous solution of a specific emulsifier to an organic solvent solution of butyl rubber, and mixing by stirring with an agitating blade such as an angled flat blade or a helical screw, a homodisper, or a homomixer. Or after emulsification and dispersion by a method such as mixing with an external emulsifier such as a line mixer and further mixing with dilution water using an emulsifier, the organic solvent is, for example, 60 ° C., 720 to 640 mmHg. (96.0 to 85.3 kPa). The content of the organic solvent remaining after the removal is 1% or less, preferably 0.5% or less, particularly preferably 0.2% or less.

  Any organic solvent can be used as long as it dissolves butyl rubber and can be distilled off after emulsification. Examples of preferable solvents include saturated aliphatic organic solvents such as hexane, isohexane, pentane, cyclohexane, heptane, and isooctane, and aromatic organic solvents such as xylene, toluene, and benzene. Among these, hexane, isohexane, cyclohexane, xylene, toluene and the like are preferable from the viewpoint of safety and ease of use. Further, carbon dioxide in a supercritical state can be used as a solvent having the same role instead of the hydrocarbon solvent as described above. Therefore, the organic solvent used in the present invention includes supercritical carbon dioxide.

  The particle size of the particles contained in the aqueous emulsion dispersion of butyl rubber varies depending on the method of emulsification, the amount of emulsifier used, the concentration of the aqueous emulsion dispersion of butyl rubber, etc., but is usually 5 μm or less, more preferably 0.5-3 μm, Particularly preferred is 0.7 to 2 μm. If the particle size is too large, the stability of the emulsified dispersion tends to be insufficient. Conversely, if the particle size is too small, it is difficult to produce, and the viscosity tends to increase, which tends to cause problems in pumping. Here, the average particle diameter is measured and calculated by a laser diffraction scattering method using SALD2000 manufactured by Shimadzu Corporation.

  The aqueous emulsified dispersion of the present invention thus produced has good emulsifiability and protective colloid properties of the specific emulsifier, and therefore has good temporal stability and mechanical stability.

  When the aqueous emulsion dispersion of the present invention is produced, a thickener may be further added. Addition of a thickener makes it difficult for secondary agglomeration to occur due to the suppression of Brownian motion in the short term, and a thickening with good storage stability that prevents separation of water and butyl rubber even when stored for a long period of time. It becomes an emulsified dispersion containing the agent.

  Specific examples of the thickener include, for example, bentonite, aluminosilicate, nonionic cellulose derivatives such as hydroxyethyl cellulose, methyl cellulose, ethyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl ethyl cellulose, hydroxyethyl ethyl cellulose, and the like. Xanthan gum, rhamsan gum and the like can be mentioned.

  These may be used alone or in combination of two or more. Of these, hydroxyalkylalkylcelluloses such as hydroxypropylmethylcellulose and hydroxyethylmethylcellulose, xanthan gum and rhamsan gum are preferred among the nonionic cellulose derivatives.

  When the thickener is added, it is preferable to add 0.1 to 3 parts, more preferably 0.1 to 2 parts, with respect to 100 parts of butyl rubber. The addition amount when the thickener is a nonionic cellulose derivative is 0.1 to 2 parts, further 0.4 to 1 part, and the addition amount when xanthane gum and / or rhamsan gum is 0. 1 to 3 parts, more preferably 0.1 to 2 parts is preferred from the viewpoint of providing the storage stability of the emulsified dispersion of the present invention and viscosity suitable for pumping. When the amount used is too small, the storage stability of the emulsified dispersion is not sufficiently improved, and when it is too large, the viscosity becomes too high and pumping tends to be difficult.

  When xanthan gum and / or lambzan gum is used as a thickener and used in combination with other thickeners, the amount of other thickener used is 50 parts or less, with the total weight of the thickener being 100 parts, The amount is preferably 40 parts or less from the viewpoint of the storage stability of the aqueous emulsion dispersion of the present invention and the viscosity during pumping. Also, when other thickeners are used, it is preferable from the viewpoint of storage stability and pumping that 0.1 part or more of xanthan gum and / or ramzan gum is contained with respect to 100 parts of butyl rubber.

  As described above, the aqueous emulsion dispersion of the present invention generally has a solid content of 40 to 65%, more preferably 45 to 60%, and a viscosity (measured with a B-type viscometer) of 100 to 700 mPa · s. Furthermore, it is 150 to 500 mPa · s, and by adding a thickener, the solid concentration is 40 to 65%, further 45 to 60%, and the viscosity (measured with a B-type viscometer) is 200. It is preferably ˜6000 mPa · s, more preferably 350 to 4,000 mPa · s.

  The aqueous emulsion dispersion of butyl rubber obtained by the present invention can be used by mixing with other rubber latex or resin emulsion. Various commercially available rubber latexes can be used, and examples thereof include natural rubber latex, SBR latex, carboxy-modified SBR latex, BR latex, NBR latex, and CR latex.

  As resin emulsions, polyacryl emulsion, polyacryl-silicon emulsion, polyacryl-fluorine emulsion, polyacryl-styrene emulsion, polyvinyl acetate emulsion, EVA emulsion, polyurethane emulsion, silicone emulsion, epoxy emulsion, EP rubber emulsion, SBS emulsion And SIS emulsion. Moreover, you may mix and use an oil emulsion and an asphalt emulsion.

  However, when mixing with latexes having different ionicity, the workability is not affected.

 A water-based emulsified dispersion of butyl rubber obtained according to the present invention includes an inorganic filler, polymer powder, magnetic powder, metal powder, conductive carbon, oil, plasticizer, tackifier, flame retardant, and dispersion stabilizer as necessary. In addition, pigments, antiseptic / antifungal agents, antioxidants, ultraviolet absorbers, antifoaming agents, colloidal sulfur, vulcanization accelerators, vulcanizing agents and the like may be added. Of these, those which are dissolved in the solvent to be used may be emulsified at the same time as butyl rubber in a state of being added to the butyl rubber solution before emulsification.

  Furthermore, you may use together with water reactive compounds, such as a cement, a gypsum, lime, and an isocyanate compound.

  The aqueous emulsion dispersion of butyl rubber obtained by the present invention has excellent vibration damping properties, gas barrier properties, electrical properties, mechanical strength, weather resistance, heat resistance, ozone resistance, chemical resistance, and adhesion to polyolefins. Suitable for vibration damping materials, adhesives, adhesives, paints, coating materials, inks, packaging laminate films, packings, puncture repair agents, waterproof materials, moisture-proof materials, electrical insulation materials, insulation moisture-proof materials, etc. Can be used. Moreover, it can mix with other rubber latex and resin emulsion, and can be used for the improvement of the said characteristic.

  Further, it may be applied in the form of a sheet or a tape after being dried.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example, this invention is not limited at all by these.

  The contents and abbreviations of the main raw materials used in the examples are described below.

[Butyl rubber (IIR)]
-JSR Co., Ltd. product, JSR Butyl 268, Mooney viscosity ML _{1 + 8} (125 degreeC) 51
[emulsifier]
・ Polyoxyethylene styrenated phenyl ether aqueous solution: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neugen EA-207D (55% active ingredient aqueous solution)
Polyoxyethylene tridecyl ether: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neugen TDS-500F
Polyoxyethylene lauryl ether: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., DSK NL-450
Polyoxyethylene isodecyl ether: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neugen SD-400
Polyoxyethylene oleyl cetyl ether: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neugen ET-189
Alkylbenzene sulfonate aqueous solution: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen S-20F (20% active ingredient aqueous solution)
Alkyl sulfate: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Monogen Y-100
[Thickener]
・ Xanthan gum: Dainippon Pharmaceutical Co., Ltd., KELDENT

  Below, the preparation method of the water-system emulsified dispersion of IIR of an Example and a comparative example is demonstrated. The self-adhesion property of the obtained IIR aqueous emulsion dispersion was measured according to the following measurement method. The results are shown in Table 1.

<Example 1>
IIR 100 parts (600 g) and toluene 400 parts (2400 g) were charged into an emulsifier equipped with a disper, a mixer and an anchor (manufactured by Tokushu Kika Kogyo Co., Ltd., TK combination type) and heated to 90 ° C. IIR was dissolved. After dissolution, the internal temperature was kept at 50 ° C., and 109 g of polyoxyethylene styrenated phenyl ether aqueous solution (10 parts of active ingredient) diluted with 70 g of hot water at 50 ° C. was added, and the peripheral speed of the mixer was 12.8 m / s, After emulsification at a disper peripheral speed of 9.6 m / s and an anchor rotation speed of 60 rpm, 250 parts (1500 g) of diluting water was uniformly added dropwise over 60 minutes to obtain an IIR aqueous emulsion dispersion.

  As a thickener, 20 parts (120 g) of a 1% aqueous solution of xanthan gum was added and mixed for 10 minutes, and then the IIR aqueous emulsion dispersion was 50 ° C. using a rotary evaporator (Tokyo Rika Kikai Co., Ltd., N-11 type). Toluene was distilled off at 720 to 640 mmHg (96.0 to 85.3 kPa) to make the residual toluene amount 0.05%. An IIR aqueous emulsion dispersion having a solid content of 50% and a particle size of 1.2 μm was obtained.

<Example 2>
IIR 100 parts (600 g) and toluene 400 parts (2400 g) were charged into an emulsifier equipped with a disper, a mixer and an anchor (manufactured by Tokushu Kika Kogyo Co., Ltd., TK combination type) and heated to 90 ° C. IIR was dissolved. After dissolution, the internal temperature was kept at 50 ° C., 10 parts (60 g) of polyoxyethylene tridecyl ether dissolved in 240 g of hot water at 50 ° C. was added, the peripheral speed of the mixer was 12.8 m / s, the peripheral speed of the disper After emulsification at 9.6 m / s and an anchor rotation speed of 60 rpm, 250 parts (1500 g) of diluted water was uniformly added dropwise over 60 minutes to obtain an aqueous IIR emulsion dispersion.

  As a thickener, 20 parts (120 g) of a 1% aqueous solution of xanthan gum was added and mixed for 10 minutes, and then the IIR aqueous emulsion dispersion was mixed with a rotary evaporator (Tokyo Rika Kikai Co., Ltd., N-11 type) at 50 ° C. Toluene was distilled off at 720 to 640 mmHg (96.0 to 85.3 kPa) to make the residual amount of toluene 0.05%. An IIR aqueous emulsion dispersion having a solid content of 50% and a particle size of 1.2 μm was obtained.

<Example 3>
IIR 100 parts (600 g) and toluene 400 parts (2400 g) were charged into an emulsifier equipped with a disper, a mixer and an anchor (manufactured by Tokushu Kika Kogyo Co., Ltd., TK combination type) and heated to 90 ° C. IIR was dissolved. After dissolution, the internal temperature was kept at 50 ° C., 10 parts (60 g) of polyoxyethylene lauryl ether dissolved in 240 g of hot water at 50 ° C. was added, the peripheral speed of the mixer was 12.8 m / s, the peripheral speed of the disper was 9 After emulsification at an anchor rotational speed of 60 rpm, 250 parts (1500 g) of diluted water was uniformly added dropwise over 60 minutes to obtain an IIR aqueous emulsion dispersion.

  As a thickener, 20 parts (120 g) of a 1% aqueous solution of xanthan gum was added and mixed for 10 minutes, and then the IIR aqueous emulsion dispersion was mixed with a rotary evaporator (Tokyo Rika Kikai Co., Ltd., N-11 type) at 50 ° C. Toluene was distilled off at 720 to 640 mmHg (96.0 to 85.3 kPa) to make the residual amount of toluene 0.05%. An IIR aqueous emulsion dispersion having a solid content of 50% and a particle size of 1.3 μm was obtained.

<Example 4>
IIR 100 parts (600 g) and toluene 400 parts (2400 g) were charged into an emulsifier equipped with a disper, a mixer and an anchor (manufactured by Tokushu Kika Kogyo Co., Ltd., TK combination type) and heated to 90 ° C. IIR was dissolved. After dissolution, the internal temperature was kept at 50 ° C., 10 parts (60 g) of polyoxyethylene lauryl ether dissolved in 240 g of hot water at 50 ° C. was added, the peripheral speed of the mixer was 12.8 m / s, the peripheral speed of the disper was 9 After emulsification at an anchor rotational speed of 60 rpm, 250 parts (1500 g) of diluted water was uniformly added dropwise over 60 minutes to obtain an IIR aqueous emulsion dispersion.

  As a thickener, 20 parts (120 g) of a 1% aqueous solution of xanthan gum was added and mixed for 10 minutes, and then the IIR aqueous emulsion dispersion was mixed with a rotary evaporator (Tokyo Rika Kikai Co., Ltd., N-11 type) at 50 ° C. Toluene was distilled off at 720 to 640 mmHg (96.0 to 85.3 kPa) to make the residual amount of toluene 0.05%. An IIR aqueous emulsion dispersion having a solid content of 50% and a particle size of 1.3 μm was obtained.

<Example 5>
IIR 100 parts (600 g) and toluene 400 parts (2400 g) were charged into an emulsifier equipped with a disper, a mixer and an anchor (manufactured by Tokushu Kika Kogyo Co., Ltd., TK combination type) and heated to 90 ° C. IIR was dissolved. After dissolution, the internal temperature was kept at 50 ° C., 10 parts (60 g) of polyoxyethylene oleyl cetyl ether dissolved in 240 g of hot water at 50 ° C. was added, and the peripheral speed of the mixer was 12.8 m / s, the peripheral speed of the disper After emulsification at 9.6 m / s and an anchor rotation speed of 60 rpm, 250 parts (1500 g) of diluted water was uniformly added dropwise over 60 minutes to obtain an aqueous IIR emulsion dispersion.

  As a thickener, 20 parts (120 g) of a 1% aqueous solution of xanthan gum was added and mixed for 10 minutes, and then the IIR aqueous emulsion dispersion was mixed with a rotary evaporator (Tokyo Rika Kikai Co., Ltd., N-11 type) at 50 ° C. Toluene was distilled off at 720 to 640 mmHg (96.0 to 85.3 kPa) to make the residual amount of toluene 0.05%. An IIR aqueous emulsion dispersion having a solid content of 50% and a particle size of 1.3 μm was obtained.

<Example 6>
IIR 100 parts (600 g) and toluene 400 parts (2400 g) were charged into an emulsifier equipped with a disper, a mixer and an anchor (manufactured by Tokushu Kika Kogyo Co., Ltd., TK combination type) and heated to 90 ° C. IIR was dissolved. After dissolution, the internal temperature was kept at 50 ° C., and 109 g of polyoxyethylene styrenated phenyl ether aqueous solution (10 parts of active ingredient) diluted with 70 g of hot water at 50 ° C. was added, and the peripheral speed of the mixer was 12.8 m / s, After emulsification at a disper peripheral speed of 9.6 m / s and an anchor rotation speed of 60 rpm, 250 parts (1500 g) of dilution water was uniformly added dropwise over 60 minutes to obtain an IIR aqueous emulsion dispersion.

  Without adding a thickener, the IIR aqueous emulsion dispersion was subjected to toluene at 50 ° C. and 720 to 640 mmHg (96.0 to 85.3 kPa) on a rotary evaporator (Tokyo Rika Kikai Co., Ltd., N-11 type). Distilled to a residual toluene content of 0.05%. An IIR aqueous emulsion dispersion having a solid content of 50% and a particle size of 1.2 μm was obtained.

<Comparative example 1> (When emulsified with an emulsifier other than the claims (anionic emulsifier))
IIR 100 parts (600 g) and toluene 400 parts (2400 g) were charged into an emulsifier equipped with a disper, a mixer and an anchor (manufactured by Tokushu Kika Kogyo Co., Ltd., TK combination type) and heated to 90 ° C. IIR was dissolved. After dissolution, the internal temperature is kept at 50 ° C., 210 g of alkylbenzene sulfonate aqueous solution (active ingredient 7 parts) is added, the peripheral speed of the mixer is 12.8 m / s, the peripheral speed of the disper is 9.6 m / s, and the anchor rotates. After emulsifying at several 60 rpm, 250 parts (1500 g) of diluted water was uniformly added dropwise over 60 minutes to obtain an IIR aqueous emulsion dispersion.

  As a thickener, 20 parts (120 g) of a 1% aqueous solution of xanthan gum was added and mixed for 10 minutes, and then the IIR aqueous emulsion dispersion was mixed with a rotary evaporator (Tokyo Rika Kikai Co., Ltd., N-11 type) at 50 ° C. Toluene was distilled off at 720 to 640 mmHg (96.0 to 85.3 kPa) to make the residual amount of toluene 0.05%. An IIR aqueous dispersion having a solid content of 50% and a particle size of 1.0 μm was obtained.

<Comparative Example 2> (When emulsified with an emulsifier other than the claims)
IIR 100 parts (600 g) and toluene 400 parts (2400 g) were charged into an emulsifier equipped with a disper, a mixer and an anchor (manufactured by Tokushu Kika Kogyo Co., Ltd., TK combination type) and heated to 90 ° C. IIR was dissolved. After dissolution, the internal temperature was kept at 50 ° C., and 7 parts (42 g) of alkyl sulfate dissolved in 180 g of hot water at 50 ° C. were added, and the peripheral speed of the mixer was 12.8 m / s, and the peripheral speed of the disper was 9.6 m. / S, after emulsification at an anchor rotation speed of 60 rpm, 250 parts (1500 g) of dilution water was uniformly added dropwise over 60 minutes to obtain an aqueous IIR emulsion dispersion.

  After adding 20 parts (120 g) of a 1% aqueous solution of xanthan gum as a thickener and mixing for 10 minutes, the IIR emulsion dispersion was 50 ° C. on a rotary evaporator (Tokyo Rika Kikai Co., Ltd., N-11 type), Toluene was distilled off at 720 to 640 mmHg (96.0 to 85.3 kPa) to make the residual amount of toluene 0.05%. An IIR aqueous emulsion dispersion having a solid content of 50% and a particle size of 1.1 μm was obtained.

[Self-adhesion]
The obtained IIR aqueous emulsion dispersion is coated on a polyester film with a bar coater at a dry film thickness of 50 μm, dried at room temperature to form a film, and then overcoated again with a dry film thickness of 50 μm. After the overcoat layer was sufficiently dried, the boundary between the upper layer and the lower layer was scratched to confirm whether interfacial peeling occurred. If interfacial peeling occurs easily, the self-adhesiveness was evaluated as poor (x), and the case where interfacial peeling did not occur was evaluated as good (◯).

  Next, vibration damping, adhesiveness and electrical characteristics were evaluated.

<Example 7> Evaluation of vibration damping property The IIR aqueous emulsion dispersion obtained in Example 1 was applied to a galvanized steel sheet (1 x 25 x 300 mm), dried to a thickness of 0.2 mm, and another zinc Steel sheets were bonded together and fixed with clips to create test pieces for evaluation. The areal density was 15.9 kg / m ² . The central part of the test piece was flexibly vibrated by an electromagnetic non-contact excitation method, and received by a piezoelectric accelerometer, and vibration mobility was measured. The measurement temperature was changed from −30 ° C. to 50 ° C., and the loss coefficient η at a frequency of 500 Hz was measured. The results are shown in FIG.

  As shown in FIG. 1, the water-based emulsion dispersion of the present invention was confirmed to have a vibration damping property equivalent to that of solid butyl rubber.

<Example 8> Evaluation of adhesion The IIR aqueous emulsion dispersion obtained in Example 1 was coated on an EPDM sheet having a thickness of 1 mm so as to have a dry thickness of 0.1 mm, and dried at room temperature. This was pressure-bonded with a two-sheet laminating roller, cut into a 25 mm × 150 mm strip, and subjected to a 180 ° peel test at a speed of 300 mm / min. As a result, the peel strength was 8 N / 25 mm.

<Example 9> Evaluation of electrical characteristics Using the IIR aqueous emulsion dispersion obtained in Example 1, a film having a dry thickness of 0.78 mm was prepared, and the volume resistivity was measured by the following method. As a result, the volume resistivity was 2.26 × 10 ¹² (Ωcm).

Volume resistivity measurement conditions:
Test method: Conforms to IEC 60093 Test conditions: 23 ° C., applied voltage 500 V × 1 minute State preparation: 23 ° C./55%×48 hours or more Tester: Superinsulator R-503 manufactured by Kawaguchi Electric Mfg. Co., Ltd.

  The aqueous emulsion dispersion according to the present invention can be used as a paint, primer, ink, adhesive, or sealing resin. Moreover, it is also possible to mix | blend and use resin, such as aqueous acryl, urethane, and polyester.

  As a damping material, it can also be used as a water-based coating-type damping material or a coating-dried sheet-like damping material, such as automobiles, railways, ships, architecture, industrial machinery, housing equipment, acoustic equipment, home appliances, Useful for vibration control of office equipment and aircraft.

10 is a graph showing measurement results of vibration damping properties of Example 7.

Claims (5)

  An aqueous emulsified dispersion of butyl rubber, wherein the butyl rubber is emulsified and dispersed with an emulsifier containing at least one nonionic emulsifier.   2. The aqueous emulsified dispersion of butyl rubber according to claim 1, wherein the amount of the nonionic emulsifier is 1 to 20 parts by weight per 100 parts by weight of the butyl rubber.   A rubber solution obtained by dissolving butyl rubber in an organic solvent and an emulsifier containing at least one nonionic emulsifier are mixed and stirred to emulsify the rubber solution, and then the emulsified rubber solution is diluted with water. Thereafter, the organic solvent is distilled off, and a method for producing an aqueous emulsion dispersion of butyl rubber.   The blend amount of the nonionic emulsifier is 1 to 20 parts by weight with respect to 100 parts by weight of the butyl rubber, and the solid content after the organic solvent is distilled off is 40 to 65% by weight. Item 4. A method for producing an aqueous emulsion dispersion of butyl rubber according to Item 3. The organic solvent is at least one selected from the group consisting of hexane, isohexane, pentane, cyclohexane, heptane, isooctane, xylene, toluene, benzene, and carbon dioxide in a supercritical state. A method for producing an aqueous emulsified dispersion of butyl rubber according to 3 or 4.

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