WO2013077379A1 - Heat storage material, heat storage device, heat storage microcapsule - Google Patents

Abstract

[Problem] To provide a heat storage material such that a dispersoid maintains a stable particle diameter even with repeated phase changes made during use, and that is capable of withstanding long-term use, also provided is a heat storage device that uses the same. [Solution] A heat storage material obtained by dispersion of particles containing a heat storage substance and an elastomer. The heat storage material comprises at least one heat storage substance selected from the group consisting of paraffin compounds, fatty acids, ester compounds of fatty acids, aliphatic ethers, aliphatic ketones, and aliphatic alcohols.

Description

Thermal storage material, thermal storage device and thermal storage microcapsule

The present invention relates to a heat storage material used in a latent heat storage system that stores heat using latent heat generated with a phase change, and a heat storage device using the heat storage material. Moreover, this invention relates to the thermal storage microcapsule used suitably as a content component of the said thermal storage material.

In recent years, the demand for air conditioning for office buildings and homes is increasing. For this reason, in preparation for the peak of power demand in summer, development of a heat storage material that accumulates cold energy for cooling by using nighttime power has become active.

Examples of such a heat storage material include a material that uses the heat capacity and specific heat (sensible heat) of a substance, a material that uses the amount of heat (latent heat) generated with the phase change of the substance, and a material that uses the chemical reaction heat of the substance. Thermal storage materials that utilize latent heat associated with phase changes (melting and solidification) of organic compounds such as paraffin compounds and fatty acids are now widely used.

Heat storage methods are broadly divided into (1) a heat storage method in which a non-fluid heat storage material is fixed and stored in the heat storage tank, and (2) the heat storage material is made fluid and transported from the heat storage tank to the heat exchanger. There is a heat transfer system that conducts heat. In recent years, the heat transfer method has been attracting attention because of its superior thermal efficiency and controllability. As a heat storage material having fluidity, a heat storage material made of an emulsion composed of a paraffin compound as a dispersoid, water as a dispersion medium, and a surfactant is known (for example, see Patent Documents 1 and 2). .

However, the heat storage material having such fluidity has a problem that the particle size of the dispersoid becomes unstable due to repeated phase changes during use, and it is difficult to maintain its shape.

In addition, among the latent heat type heat storage materials, a heat storage capsule in which a core material that performs latent heat storage is encapsulated in a coating is because a change in the amount of heat accompanying a phase change of the core material is performed in a coating that surrounds the core material. Since the core material can be handled as particles regardless of the state, it has an advantage of easy handling.

For example, heat storage capsules obtained by reaction of melamine or urea with formaldehyde using a paraffin compound as a heat storage material and coated with melamine resin or urea resin (see, for example, Patent Document 3), poly (meth) acrylate and polystyrene derivatives Thermal storage capsules (see, for example, Patent Documents 4 and 5) that use a resin obtained by radical polymerization such as a coating as a coating have been proposed.

A heat storage microcapsule (see, for example, Patent Document 6) having a polyurethane resin or polyurea resin film obtained by reacting a polyvalent isocyanate and an active hydrogen compound with a paraffin compound as a core substance is also thermoplastic. A heat storage microcapsule (see, for example, Patent Document 7) composed of a resin outer shell and a heat storage material and a core material containing hydroxy fatty acid as a gelling agent has been proposed.

However, these heat storage capsules have a problem that, since the core material is a paraffin compound or the like, an excessive external force is applied to the heat storage capsule during the use process, and the heat storage material leaks when the coating is deteriorated or broken.

JP-A-57-40582 JP 2000-336350 A Japanese Patent No. 2988765 JP 2002-69438 A JP 2001-181611 A JP-A-7-133479 JP 2008-297503 A

In the present invention, it is intended to provide a heat storage material such as an emulsion-type heat storage material that maintains a stable particle diameter even when phase changes are repeated during use, and withstands long-term use, and a heat storage device using the same. Let it be an issue. Another object of the present invention is to provide a heat storage capsule that hardly leaks out a heat storage material even if the coating is deteriorated or broken, and a heat storage material using the same.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by the following configuration, and have completed the present invention. That is, the present invention is as follows.

[1] A heat storage material in which particles containing a heat storage material and an elastomer are dispersed, wherein the heat storage material is a paraffin compound, a fatty acid, a fatty acid ester compound, an aliphatic ether, an aliphatic ketone, and an aliphatic A heat storage material comprising at least one selected from the group consisting of alcohols. *

[2] The heat storage material according to [1], wherein the elastomer has a polystyrene equivalent weight average molecular weight of 10,000 to 700,000 as measured by gel permeation chromatography.

[3] At least one heat storage material selected from the group consisting of paraffin compounds, fatty acids, fatty acid ester compounds, aliphatic ethers, aliphatic ketones, and aliphatic alcohols, elastomers, water, and surface activity A heat storage material consisting of an emulsion containing an agent.

[4] The heat storage material according to [3], wherein the elastomer has a polystyrene-reduced weight average molecular weight of 10,000 to 700,000 as measured by a gel permeation chromatography method.

[5] The heat storage material according to [3] or [4], wherein the elastomer is a hydrogenated conjugated diene (co) polymer.

[6] The hydrogenated conjugated diene (co) polymer includes a structural unit (a-1) derived from a conjugated diene compound, a polymer block (A) having a vinyl bond content of less than 30 mol%, and a conjugated diene 50 masses of the polymer block (B) having a vinyl bond content of 30 to 95 mol% including the structural unit (b-1) derived from the compound and the structural unit (c-1) derived from the alkenyl aromatic compound [5], obtained by hydrogenating a block (co) polymer having at least one polymer block selected from the group consisting of The heat storage material described in 1.

[7] In the above [6], the block (co) polymer has at least a polymer block (A) and a polymer block (B), and at least one terminal is the polymer block (A). The heat storage material described.

[8] The heat storage material according to any one of [3] to [7], which is an oil-in-water emulsion in which at least the heat storage material and the elastomer are dispersoids and the water is a dispersion medium.

[9] A heat storage device obtained by filling a container with the heat storage material according to any one of [1] to [8].

[10] A core comprising an elastomer and at least one heat storage material selected from the group consisting of paraffin compounds, fatty acids, fatty acid ester compounds, aliphatic ethers, aliphatic ketones, and aliphatic alcohols. Thermal storage microcapsules in which the substance is covered by a coating.

[11] The heat storage microcapsule according to [10], wherein the elastomer has a polystyrene-equivalent weight average molecular weight of 10,000 to 700,000 as measured by a gel permeation chromatography method.

[12] The heat storage microcapsule according to [10] or [11], wherein the elastomer is a hydrogenated conjugated diene (co) polymer.

[13] The hydrogenated conjugated diene (co) polymer includes a structural unit (a-1) derived from a conjugated diene compound, a polymer block (A) having a vinyl bond content of less than 30 mol%, and a conjugated diene 50 masses of the polymer block (B) having a vinyl bond content of 30 to 95 mol% including the structural unit (b-1) derived from the compound and the structural unit (c-1) derived from the alkenyl aromatic compound % Obtained by hydrogenating a block (co) polymer having at least one polymer block selected from the group consisting of a polymer block (C) containing more than%, and [12] Thermal storage microcapsules as described in 1.

[14] In the above [13], the block (co) polymer has at least a polymer block (A) and a polymer block (B), and at least one terminal thereof is the polymer block (A). Thermal storage microcapsule as described.

[15] The film is a melamine resin, urea resin, polystyrene resin, acrylic resin, styrene- (meth) acrylic acid ester copolymer resin, acrylonitrile-styrene copolymer resin, polyester resin, polyurethane resin, polyurea resin, and polyamide resin. The heat storage microcapsule according to any one of [10] to [14], which is a film made of at least one resin selected from the group consisting of:

[16] A heat storage material comprising the heat storage microcapsule according to any one of [10] to [15].

[17] The heat storage material according to [1], wherein the particles containing the heat storage material and the elastomer are the heat storage microcapsules according to any one of [10] to [15].

According to the present invention, there is provided a heat storage material such as an emulsion-type heat storage material that maintains a stable particle size even when phase changes are repeated during use, and withstands long-term use, and a heat storage device using the same. Can do. In addition, according to the present invention, it is possible to provide a heat storage capsule and a heat storage material using the heat storage capsule in which leakage of the heat storage material hardly occurs even when the coating is deteriorated or broken.

Hereinafter, embodiments of the present invention will be described. The present invention is not limited to the following embodiments, and the scope of the present invention includes those appropriately modified and improved based on the ordinary knowledge of those skilled in the art without departing from the spirit of the present invention. It should be understood that it enters.

The heat storage material of the present invention is a heat storage material in which particles containing a heat storage material and an elastomer (hereinafter also referred to as “heat storage material particles”) are dispersed, and the heat storage material is an ester of a paraffin compound, a fatty acid, or a fatty acid. It contains at least one selected from the group consisting of compounds, aliphatic ethers, aliphatic ketones, and aliphatic alcohols.

Further, the polystyrene-equivalent weight average molecular weight of the elastomer measured by gel permeation chromatography method is preferably 10,000 to 700,000, more preferably 100,000 to 500,000, and more preferably 200,000 to Particularly preferred is 500,000.

The average particle diameter of the heat storage material particles is exemplified by 0.01 to 3000 μm, and the content of the heat storage material particles is typically 1 to 80% by mass, preferably 3 to 70% by mass in 100% by mass of the heat storage material. Is done. The average particle diameter of the heat storage material particles can be obtained as a MV value (Mean Volume Diameter) by a laser diffraction / scattering particle size analyzer.

As a first aspect of the heat storage material of the present invention, an emulsion type heat storage material made of an emulsion containing a heat storage material, an elastomer, water, and a surfactant may be mentioned. In addition, as a second aspect of the heat storage material of the present invention, there is a heat storage material in which the heat storage material particles are dispersed in at least one selected from the group consisting of concrete, mortar, various rubbers, synthetic resins, paints, and fibers. Can be mentioned.

The heat storage microcapsule of the present invention is a capsule in which a core material containing a heat storage material and an elastomer is coated with a coating. As will be described later, the heat storage microcapsules of the present invention can be suitably used as heat storage material particles contained in the heat storage material of the second aspect. Moreover, the heat storage microcapsules of the present invention can be used alone or together with a heat transfer medium such as water by filling a container such as a packaging container or a metal container.

[1. Heat storage material of first aspect: emulsion type heat storage material]
The emulsion-type heat storage material that is the heat storage material of the first aspect of the present invention comprises an emulsion containing a heat storage material, an elastomer, water, and a surfactant. In this specification, the heat storage material, the elastomer, and other components used as necessary may be collectively referred to as “dispersoid”, and water may be referred to as “dispersion medium”.

<Dispersed quality>
In the emulsion type heat storage material of the present invention, the heat storage material and the elastomer are mixed to form oil droplets in such a state that the elastomer encloses the heat storage material, and becomes a dispersoid and exists in the dispersion medium. . These oil droplets correspond to the heat storage material particles.

As the heat storage material, at least one selected from the group consisting of paraffin compounds, fatty acids, fatty acid ester compounds, aliphatic ethers, aliphatic ketones, and aliphatic alcohols is preferably used. An elastomer is used to maintain a stable particle size even when the heat storage material repeats phase changes.

The emulsion type heat storage material of the present invention is an oil-in-water emulsion (hereinafter referred to as “O / O”) in which fine oil droplets of a heat storage material and an elastomer are dispersed using water as a dispersion medium in water serving as a dispersion medium. Also referred to as “W emulsion”).

Details of the heat storage material and elastomer will be described later.

The content of the elastomer in the dispersoid is preferably 1 to 33% by mass, more preferably 1 to 20% by mass in 100% by mass of the dispersoid. From the viewpoint of preventing instability of the emulsion and obtaining a sufficient amount of latent heat and heat storage effect, it is preferably not less than the above lower limit value, and also prevents coalescence of dispersoids during freezing of the emulsion, From the viewpoint of maintaining fluidity, the upper limit value is preferred.

The average particle size of the oil droplets in the emulsion is preferably from 0.1 to 30 μm, more preferably from 0.1 to 25 μm, particularly preferably from 0.3 to 20 μm. From the viewpoint of preventing instability of the emulsion and obtaining a sufficient amount of latent heat and heat storage effect, it is preferably not less than the above lower limit value, and also prevents coalescence of dispersoids during freezing of the emulsion, From the viewpoint of maintaining fluidity, the upper limit value is preferred.

Here, “average particle diameter of oil droplets” in the present specification means a volume average particle diameter measured by a laser diffraction / scattering method. The volume average particle diameter can be obtained as an MV value by measuring the obtained emulsion with a laser diffraction / scattering particle size analyzer.

As a method for obtaining the emulsion-type heat storage material of the present invention, after mixing only the components constituting the dispersoid and the surfactant, this may be mixed and stirred together with the dispersion medium, or all the components may be mixed and stirred together. May be. The mixing and stirring conditions are not particularly limited, but a known stirring means is used. From the viewpoint of obtaining an emulsion suitable for productivity and a heat storage material, the stirring speed is 1,000 to 100,000 rpm, 1 minute to 1 hour. It is preferable to mix and stir under the conditions.

<Surfactant>
In order to mix and disperse the dispersoid and water and uniformly mix and disperse, there is a method of emulsifying using a surfactant. The surfactant has an effect of protecting the oil droplets and an effect of stabilizing the oil droplets by preventing aggregation and coalescence of the oil droplets in the dispersion medium.

As the surfactant, for example, known ones such as a nonionic surfactant and an anionic surfactant can be used. From the viewpoint of the stability of the dispersoid, a nonionic surfactant is preferably used. Specifically, there are surfactants such as ether type, alkylphenol type, ester type, sorbitan ester type, sorbitan ester ether type and the like. These may be used alone or in combination of two or more.

The addition amount of the surfactant is preferably 0.1 to 20 parts by mass with respect to 100 parts by mass of the heat storage material. From the viewpoint of obtaining an emulsion in which the dispersoid is sufficiently dispersed in the dispersion medium, 0.1% is added. More preferably, it is ˜10 parts by mass.

<Dispersion medium>
In the emulsion type heat storage material of the present invention, water used as a dispersion medium may be industrial water, but ion exchange water or distilled water is preferable because it hardly affects the heat storage material.

In the emulsion type heat storage material of the present invention, the content of the dispersoid is usually 1 to 80% by mass, preferably 3 to 70% by mass in 100% by mass of the emulsion type heat storage material. When the content is in the above range, it is preferable from the viewpoint of obtaining an industrially useful heat storage amount while maintaining the stability of the dispersoid.

<Applications of emulsion-type heat storage materials>
Since the emulsion-type heat storage material of the present invention is an emulsion that is excellent in stability even when phase changes are repeated, it can be filled into a container such as a packaging container or a metal container to form a heat storage device. Further, the heat storage device alone or together with a heat transfer medium such as water can be used in various fields such as an air conditioning application, an electronic component temperature rise prevention application, and a target article heat insulation application. Moreover, the emulsion-type heat storage material of the present invention can be used as a heat source for air conditioning by filling a heat storage tank to store the amount of external heat. Furthermore, the emulsion type heat storage material is filled in an air conditioning circuit that circulates between the heat storage tank and the heat exchanger, thereby being used as a heat transfer medium (also referred to as brine).

[2. Heat storage material of second aspect]
The heat storage material according to the second aspect of the present invention is a heat storage material in which the heat storage material particles are dispersed in at least one selected from the group consisting of concrete, mortar, various rubbers, synthetic resins, paints and fibers.

Such heat storage materials are used for air conditioning in public facilities such as hotels; canisters for automobiles, etc .; for preventing temperature rise of electronic components such as IC chips; textiles for clothing, organ transport containers, concrete materials for buildings, etc. It can be used in various fields such as heat retention applications; antifogging applications such as curve mirrors;

[3. Thermal storage microcapsule
The heat storage microcapsule of the present invention is suitably used as a component of the heat storage material of the present invention, that is, a heat storage material particle. The heat storage microcapsule of the present invention has a configuration in which a core material containing a heat storage material and an elastomer is covered with a coating. That is, the heat storage microcapsule of the present invention has a configuration in which a film is formed around a core material containing a heat storage material and an elastomer. In the present specification, the heat storage material, the elastomer, and other components used as necessary may be collectively referred to as a “core material”.

<Core material>
As the heat storage material, at least one selected from the group consisting of paraffin compounds, fatty acids, fatty acid ester compounds, aliphatic ethers, aliphatic ketones, and aliphatic alcohols is preferably used. An elastomer is used to prevent leakage of the heat storage material even if the coating deteriorates or breaks.

Details of the heat storage material and elastomer will be described later.

The ratio of the heat storage material in the heat storage microcapsule of the present invention (heat storage material ratio) is the same as the heat storage microcapsule and the amount of latent heat derived from the heat storage material in the heat storage microcapsule (kJ / kg). It can be calculated as a value divided by the amount of latent heat (kJ / kg) derived from the same heat storage material × 100 (%). The ratio of the heat storage material is preferably 40 to 80%, more preferably 50 to 70%. From the viewpoint of obtaining a practical amount of latent heat, 50% or more is preferable, and from the viewpoint of obtaining strength against the external force of the heat storage microcapsule, it is preferably 70% or less.

<Coating>
Examples of the resin constituting the film of the heat storage microcapsule of the present invention include melamine resin, urea resin, polystyrene resin, acrylic resin, styrene- (meth) acrylate copolymer resin, acrylonitrile-styrene copolymer resin, polyester resin. , At least one resin selected from the group consisting of polyurethane resins, polyurea resins, and polyamide resins.

As the resin constituting the film obtained by the In Situ method described later, for example, melamine resin, urea resin, polystyrene resin, acrylic resin, styrene- (meth) acrylate copolymer resin, acrylonitrile-styrene copolymer resin are preferable. Can be mentioned.

In addition, in the range which can maintain the effect calculated | required by the heat storage use, the said resin may contain the other monomer for the purpose of providing a function, and the said resin may be bridge | crosslinked.

<Shape, average particle size>
The heat storage microcapsules of the present invention can be used in the form of powder, granules or the like. The shape of the heat storage microcapsule is not particularly limited, and examples thereof include a spherical shape, an elliptical shape, a daruma shape, a weight shape, a box shape, and a rod shape.

The average particle size of the heat storage microcapsules of the present invention prevents breakage due to external forces such as mechanical shearing force and impact, and when the heat storage microcapsules are dispersed in a dispersion medium and used as a dispersion, the viscosity increase during dispersion is increased. From the viewpoint of prevention, it is preferably 0.01 to 3000 μm, more preferably 0.1 to 1000 μm, and particularly preferably 1.0 to 100 μm.

In the present invention, the “average particle diameter of the heat storage microcapsule” means a volume average particle diameter measured by a laser diffraction / scattering method. The volume average particle diameter can be obtained as an MV value by dispersing the obtained microcapsules in an aqueous medium and using a laser diffraction / scattering particle size analyzer.

The average particle size of the heat storage microcapsules of the present invention can be set to a desired value by adjusting and changing the following conditions, for example. (1) Operation conditions such as the number of revolutions of stirring and time of the atomizer (also referred to as an emulsifier, a disperser, etc.), (2) Type of emulsifier (anionic surfactant, nonionic surfactant, etc.) Monomer type surfactant such as sodium alkylbenzene sulfonate, polymer type surfactant such as sodium polyacrylate), (3) concentration of surfactant, (4) temperature of emulsion during emulsification, (5) Emulsification ratio (mass ratio of water phase to oil phase).

<Applications of thermal storage microcapsules>
The heat storage microcapsule of the present invention can be used as a heat storage material for various applications by being contained in other substances. The heat storage material in the present invention is not particularly limited, but the heat storage microcapsule of the present invention is used together with other components. For example, the heat storage microcapsule is applied to concrete, mortar, various rubbers, synthetic resins, paints, fibers, etc. Examples thereof include those in which the heat storage microcapsules are mixed alone or together with a heat transfer medium such as water and filled in a container such as a packaging container or a metal container.

Such heat storage materials are used for air conditioning in public facilities such as hotels; canisters for automobiles, etc .; for preventing temperature rise of electronic components such as IC chips; textiles for clothing, organ transport containers, concrete materials for buildings, etc. It can be used in various fields such as heat retention applications; antifogging applications such as curve mirrors;

Also, the dispersion liquid in which the heat storage microcapsules of the present invention are dispersed can be filled in a heat storage tank to store the amount of external heat and used as a heat source for air conditioning. Further, the dispersion liquid is filled in an air conditioning circuit that circulates between the heat storage tank and the heat exchanger, thereby being used as a heat transfer medium.

The heat storage material of the present invention can be used together with other components described later. For example, anti-aging agents, antioxidants, antistatic agents, weathering agents, ultraviolet absorbers, flame retardants, antibacterial / antifungal agents, antiblocking agents, dispersants in heat transfer media used with heat storage microcapsules , Anti-coloring agents, rust inhibitors, specific gravity adjusting agents, thickening stabilizers, antifreezing agents, preservatives and the like.

<Method for producing thermal storage microcapsules>
In the heat storage microcapsule of the present invention, a method for obtaining a film covering the core substance is not particularly limited. For example, a method of spraying a thermoplastic resin on the surface of the heat storage material particles, a submerged drying method, a spray drying method, a pan Examples thereof include a coating method, a coacervation method, an orifice method, an interfacial polymerization method, and an In Situ (in situ) method. By these methods, the core substance can be covered with a film to obtain a desired heat storage microcapsule.

Among the above methods, in the case of microcapsules that can contain a heat storage material having a relatively high melting point, the In Situ method is preferred from the viewpoint of the heat resistance of the resulting coating. An example of the production procedure of the heat storage microcapsule of the present invention by the In Situ method is as follows.

First, a core material is prepared by dissolving an elastomer in a heat storage material. A known film forming monomer such as melamine or urea monomer is dissolved and mixed in the obtained core material. At this time, in order to further accelerate the reaction, a known amine catalyst, metal catalyst or the like may be added as necessary. Further, at this point, other additives such as a filler may be added in order to impart a desired function.

Next, the obtained mixture (oil phase mixture) is emulsified in water in the presence of an emulsifier. The mass ratio of the oil phase mixture to water during emulsification (oil phase mixture: water) is preferably 5:95 to 80:20, more preferably 10:90 to 60:40, from the viewpoint of obtaining processability. . Examples of the emulsifier at the time of emulsification include known anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants and known protective colloid agents. The concentration of the emulsifier in water is preferably 0.1% by mass to 20% by mass.

As an emulsifying device used for emulsification, turbine type, propeller type, anchor type, ribbon type and other stirring tanks, high pressure emulsifier, ultrasonic emulsifier, membrane emulsifier, homogenizer, homodisper, homomixer, line type A well-known thing, such as an emulsifier, can be used. These devices may be batch or continuous.

The emulsification temperature is preferably a temperature equal to or higher than the melting point of the core substance, and is preferably selected from the range of 0 ° C to 95 ° C. The emulsification time (in the case of continuous emulsification, the process liquid residence time in the emulsification apparatus) is preferably 1 second to 2 hours. After emulsification, a pH adjuster is added to obtain the desired pH. If necessary, a water-soluble catalyst may be added.

The resulting mixture is heated and stirred to conduct a polymerization reaction, thereby performing microencapsulation. The reaction temperature is usually 0 ° C. to 95 ° C., preferably 30 ° C. to 80 ° C. The reaction time may be 30 minutes to 30 hours, but it is preferable to set the amount of catalyst, reaction temperature, etc. so that the reaction is completed within 6 hours for practical use. A known antifoaming agent or the like may be added to the reaction system for the purpose of promoting the reaction and defoaming.

Thus, the heat storage microcapsules can be obtained in a state (hereinafter also referred to as “slurry”) contained in an aqueous dispersion in which the heat storage microcapsules are suspended in water. A known thickening stabilizer, antifreezing agent, preservative, dispersant, specific gravity adjusting agent, and other additives can be added to the resulting slurry as necessary. If necessary, the concentration of solids can be adjusted by adding dilution water. By these operations, the heat storage microcapsules of the present invention can be used as a heat storage material.

Heat storage microcapsules can be obtained by removing water from the slurry. Examples of the method for removing water include a spray drying method, a freeze drying method, a drum drying method, and the like for a microcapsule dispersion.

[4. Description of contained components)
<Heat storage material>
The heat storage material used in the heat storage material and the heat storage microcapsule of the present invention will be described below. The heat storage material is preferably a latent heat storage material from the viewpoint of heat storage capacity, and at least selected from the group consisting of paraffin compounds, fatty acids, fatty acid ester compounds, aliphatic ethers, aliphatic ketones, and aliphatic alcohols. One kind is mentioned. Among these, since they are chemically and physically stable compounds and have a high heat storage capacity, paraffin compounds, aliphatic alcohols and fatty acid ester compounds are preferred, and paraffin compounds are more preferred. In addition, in the heat storage material, the heat storage effect by the sensible heat storage using the specific heat of the material is not excluded.

The heat storage material preferably has a melting point measured by the differential scanning calorimetry (DSC method) in the range of −30 to 130 ° C. from the viewpoint of utilizing the heat storage material and the heat storage microcapsule in a wide range of fields. More preferably, the temperature is in the range of 100 ° C to 100 ° C.

Also, the heat of fusion measured by the differential scanning calorimetry (DSC method) of the heat storage material is desirably 100 kJ / kg or more from the viewpoint of using latent heat due to the phase change in various fields.

In this specification, the melting point of the heat storage material corresponds to Tim when measured according to JIS K-7121. The melting point of the heat storage material having a plurality of melting peaks was the extrapolated melting start temperature of the melting peak having a larger heat of fusion, and the latent heat was the heat of fusion of the melting peak. When there are multi-peaks and individual melting peaks cannot be distinguished, they are treated as one melting peak.

In addition, a thermal storage material may be used individually by 1 type, and may be used in combination of 2 or more type.

In the emulsion type heat storage material of the present invention, the content of the heat storage material is preferably 200 to 10000 parts by mass with respect to 100 parts by mass of the elastomer, particularly 100 parts by mass of the hydrogenated conjugated diene (co) polymer, It is more preferably from ˜3000 parts by mass, and still more preferably from 400 to 2,000 parts by mass. It is preferably 200 parts by mass or more from the viewpoint of securing a sufficient amount of latent heat when made into an emulsion, and 3000 parts by mass or less from the viewpoint of maintaining a stable particle size of the dispersoid even when the phase change is repeated. Is preferred.

In the heat storage microcapsule of the present invention, the content of the heat storage material is preferably 200 to 10,000 parts by weight, more preferably 300 to 10,000 parts by weight, based on 100 parts by weight of the elastomer, particularly 100 parts by weight of the hydrogenated conjugated diene (co) polymer. The amount is more preferably 4000 parts by mass, and still more preferably 400 to 2000 parts by mass. It is preferably 200 parts by mass or more from the viewpoint of securing a sufficient amount of latent heat when microcapsules are used, and is 4000 parts by mass or less from the viewpoint of maintaining a stable particle size of the microcapsules even when the phase change is repeated. It is preferable.

[Paraffin compounds]
Examples of the paraffin compound include paraffin compounds having 8 to 100 carbon atoms. In addition, a paraffin compound may be used individually by 1 type, and may use 2 or more types together. By using a combination of paraffin compounds having different carbon numbers, the melting point or freezing point of the heat storage material and the heat storage microcapsule can be set to a desired value.

As the paraffin compound, a compound having an alkylene group having 10 to 30 carbon atoms is more preferable. Specific examples include linear paraffins such as n-dodecane, n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane, n-nonadecane, n-icosane, and branched paraffins. Can be mentioned.

The paraffin compound is preferably a linear paraffin, that is, n-paraffin, from the viewpoint of further increasing the amount of latent heat. The n-paraffin is preferably contained in an amount of 70% by mass or more, more preferably 90% by mass or more, and particularly preferably 99% by mass or more, based on the total paraffin compound. Is preferred.

Also, petroleum wax can be used as an embodiment of a paraffin compound having 8 to 100 carbon atoms. Examples of petroleum waxes include paraffin wax (a wax that is solid at room temperature, which is produced by separating and refining oil or natural gas as a raw material from a vacuum distillation distillate), and microcrystalline wax (a reduced pressure using petroleum as a raw material). Aliphatic hydrocarbons such as wax produced at a normal temperature by separation and purification from distillation residue oil or heavy distillate oil.

From the viewpoint of heat of fusion and availability, paraffin wax having about 20 to 40 carbon atoms and microcrystalline wax having about 30 to 60 carbon atoms are preferable. Examples of paraffin wax products include “HNP-9”, “FNP-0090”, and “FT115” (all manufactured by Nippon Seiwa Co., Ltd.).

The paraffin compound preferably has a melting point measured by a differential scanning calorimetry (DSC method) in the range of −30 to 130 ° C. from the viewpoint of effective use of heat in the living temperature range and the high temperature range, and 0 to 100 More preferably in the range of ° C. Further, the heat of fusion measured by the differential scanning calorimetry (DSC method) of the paraffin compound is preferably 100 kJ / kg or more from the viewpoint of utilizing latent heat due to the phase change in various fields. In addition, the melting point of the paraffin compound in the present specification corresponds to Tim when measured according to JIS K-7121.

The melting point and heat of fusion corresponding to the paraffin compound described above are shown in parentheses below. n-undecane (−27 ° C., 160 kJ / kg), n-dodecane (−10 ° C., 185 kJ / kg), n-tridecane (−7 ° C., 150 kJ / kg), n-tetradecane (6 ° C., 230 kJ / kg) N-pentadecane (9 ° C., 165 kJ / kg), n-hexadecane (18 ° C., 230 kJ / kg), n-heptadecane (21 ° C., 170 kJ / kg), n-octadecane (28 ° C., 240 kJ / kg), n Nonadecane (32 ° C., 170 kJ / kg), n-icosane (37 ° C., 250 kJ / kg), HNP-9 (73 ° C., 215 kJ / kg), FNP-0090 (80 ° C., 230 kJ / kg), FT115 (93 ° C, 245 kJ / kg).

[fatty acid]
As the fatty acid, for example, a fatty acid having 8 to 30 carbon atoms can be used, and is roughly classified into a linear saturated fatty acid, a linear unsaturated fatty acid, a branched saturated fatty acid, and a branched unsaturated fatty acid. Of these, linear saturated fatty acids are preferably used in the present invention.

Examples of linear saturated fatty acids include octanoic acid (C8), nonanoic acid (C9), decanoic acid (capric acid) (C10), dodecanoic acid (lauric acid) (C12), and tetradecanoic acid (myristic acid) (C14). , Hexadecanoic acid (palmitic acid) (C16), octadecanoic acid (stearic acid) (C18), eicosanoic acid (C20), docosanoic acid (C22), tetracosanoic acid (C24), hexacosanoic acid (C26), octacosanoic acid (C28) And triacontanoic acid (C30) and the like. Among these, a linear saturated fatty acid having 10 to 18 carbon atoms is preferably used from the viewpoint of availability.

In addition, the melting point corresponding to the heat storage material described above is shown in parentheses below. Decanoic acid (capric acid) (16 ° C), dodecanoic acid (lauric acid) (44 ° C), tetradecanoic acid (myristic acid) (58 ° C), hexadecanoic acid (palmitic acid) (64 ° C), octadecanoic acid (stearic acid) (69 ° C).

[Ester compound of fatty acid]
As the fatty acid ester compound, for example, a long-chain fatty acid ester having 8 to 30 carbon atoms can be used. Specifically, vinyl stearate, dimethyl sebacate, butyl stearate, isopropyl stearate, isopropyl palmitate, Examples include propyl palmitate and myristyl myristate.

Among fatty acid ester compounds, methyl, ethyl, propyl, butyl and tetradecyl esters of linear saturated fatty acids having 10 to 18 carbon atoms are preferably used from the viewpoint of availability.

In addition, the melting point corresponding to the heat storage material described above is shown in parentheses below. Vinyl stearate (28 ° C), dimethyl sebacate (21 ° C), butyl stearate (19 ° C), isopropyl stearate (16 ° C), isopropyl palmitate (11 ° C), propyl palmitate (10 ° C), myristic acid Myristyl (40 ° C.).

[Aliphatic ethers]
As the aliphatic ether, for example, an aliphatic ether having 14 to 60 carbon atoms can be used, and specific examples include heptyl ether, octyl ether, tetradecyl ether, hexadecyl ether and the like. Among these, an ether compound (symmetric ether compound) having a single oxygen atom and having a symmetric structure is preferably used from the viewpoint of having a high latent heat amount and being easily synthesized.

In addition, the melting point corresponding to the heat storage material described above is shown in parentheses below. Heptyl ether (−24 ° C.), octyl ether (−7 ° C.), tetradecyl ether (45 ° C.), hexadecyl ether (55 ° C.).

[Aliphatic ketones]
As the aliphatic ketones, for example, aliphatic ketones having 8 to 30 carbon atoms can be used. Specifically, 2-nonanone, tridecanal, 2-pentadecanone, 3-hexadecanone, 8-pentadecanone, 4, 4-bicyclohexanone and the like can be mentioned. Among these, an aliphatic ketone having one oxygen atom is preferably used from the viewpoint of having a latent heat amount suitable for industrial use and being easily synthesized.

In addition, the melting point corresponding to the heat storage material described above is shown in parentheses below. 2-nonanone (-9 ° C), tridecanal (14 ° C), 2-pentadecanone (40 ° C), 3-hexadecanone (43 ° C), 8-pentadecanone (43 ° C), 4,4-bicyclohexanone (118 ° C) .

[Fatty alcohols]
As the aliphatic alcohol, for example, an aliphatic alcohol having 8 to 60 carbon atoms can be used. Specifically, 2-dodecanol, 1-tetradecanol, 7-tetradecanol, 1-octadecanol are used. 1-eicosanol, 1,10-decanediol and the like. Among these, from the viewpoint of obtaining a latent heat amount suitable for industrial use, an alcohol compound (terminal alcohol compound) in which a hydroxyl group is present at the molecular end is preferably used.

In addition, the melting point corresponding to the heat storage material described above is shown in parentheses below. 2-dodecanol (19 ° C), 1-tetradecanol (39 ° C), 7-tetradecanol (42 ° C), 1-octadecanol (59 ° C), 1-eicosanol (65 ° C), 1,10- Decanediol (73 ° C.).

<Elastomer>
The elastomer used in the heat storage material and the heat storage microcapsule of the present invention will be described below. In the heat storage material of the present invention, an elastomer is used to maintain a stable particle size of the dispersoid even when the heat storage material repeats phase changes. In the heat storage microcapsule of the present invention, an elastomer is used to prevent leakage of the heat storage material from the film even if the film is deteriorated or broken. In the heat storage microcapsule of the present invention, it is preferable that the elastomer encloses the heat storage material because leakage of the heat storage material from the coating can be suppressed.

Examples of the elastomer include conjugated diene rubber (excluding hydrogenated conjugated diene (co) polymer; the same applies hereinafter), ethylene / α-olefin copolymer rubber, and hydrogenated conjugated diene (co) polymer. Other examples include ethylene / vinyl acetate copolymers. These may be used alone or in combination of two or more.

Elastomers have rubber elasticity and work as a binder component that satisfactorily encloses the heat storage material, so that it is preferable for maintaining the shape stability of the dispersoid in the heat storage material, and in the heat storage microcapsule, the heat storage material leaks from the coating. Can be prevented. In particular, thermoplastic elastomers are preferred because they can be repeatedly molded during production, and hydrogenated conjugated dienes (co-polymers) from the viewpoints of phase separation, prevention of bleed of heat storage materials, and long-term durability. ) A polymer is more preferred.

The elastomer preferably has a polystyrene-equivalent weight average molecular weight (hereinafter also referred to as “Mw”) measured by a gel permeation chromatography method of 10,000 to 700,000, more preferably 100,000 to 500,000. The number is preferably 200,000 to 500,000. In order for the heat storage material to obtain the required mechanical properties and to prevent phase separation and bleeding of the heat storage material, it is preferable that Mw is 10,000 or more, and ensure fluidity for molding the heat storage material. Therefore, it is preferable that Mw is 700,000 or less.

[Conjugated diene rubber]
Conjugated diene rubbers (excluding hydrogenated conjugated diene (co) polymers) include, for example, natural rubber; butadiene rubber (BR), styrene-butadiene rubber (SBR), nitrile rubber (NBR), isoprene rubber (IR) ) And synthetic rubber such as butyl rubber (IIR).

[Ethylene / α-olefin copolymer rubber]
Examples of the ethylene / α-olefin copolymer rubber include a binary copolymer rubber of ethylene and α-olefin (eg, ethylene / propylene copolymer rubber (EPM)), non-conjugated with ethylene and α-olefin. And terpolymer rubber with diene (eg, ethylene / propylene / diene copolymer rubber (EPDM)).

Examples of the α-olefin include α-olefins having 3 to 20 carbon atoms, preferably 3 to 8 carbon atoms such as propylene and 1-octene. The α-olefin may be used alone or in combination of two or more.

Examples of the non-conjugated diene include ethylidene-2-norbornene. A nonconjugated diene may be used individually by 1 type, and may use 2 or more types together.

[Hydrogenated conjugated diene (co) polymer]
Examples of the hydrogenated conjugated diene (co) polymer include styrene-ethylene / butylene-styrene block (co) polymer (SEBS), styrene-ethylene / propylene-styrene block (co) polymer (SEPS), and styrene- Hydrogenated products of block (co) polymers of alkenyl aromatic compounds and conjugated diene compounds such as ethylene / butylene block (co) polymer (SEB) and styrene-ethylene / propylene block (co) polymer (SEP); styrene Alkenyl aromatic compounds such as ethylene / butylene-olefin crystal block (co) polymer (SEBC), olefin crystal block (co) polymer, olefin crystal, ethylene / butylene-olefin crystal block (co) polymer (CEBC) Olefin crystal block (co) polymers such as olefins Elastomer, and the like.

The hydrogenated conjugated diene (co) polymer contains a structural unit (a-1) derived from a conjugated diene compound (hereinafter also referred to as “structural unit (a-1)”), and has a vinyl bond content of less than 30 mol%. And a structural unit (b-1) derived from a conjugated diene compound (hereinafter also referred to as “structural unit (b-1)”) and having a vinyl bond content of 30 to 95 mol%. A polymer block containing more than 50 mass% of the polymer block (B) and the structural unit (c-1) derived from an alkenyl aromatic compound (hereinafter also referred to as “structural unit (c-1)”) ( The polymer is preferably a polymer obtained by hydrogenating a block (co) polymer having at least one polymer block selected from the group consisting of C). In the present specification, the “structural unit derived from a compound” usually means a structural unit based on the reaction of a polymerizable double bond moiety of the compound.

[Block (co) polymer]
(1) Polymer block (A)
The polymer block (A) is a polymer block containing a structural unit (a-1) derived from a conjugated diene compound. Examples of the conjugated diene compound include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, Examples include 4,5-diethyl-1,3-octadiene and chloroprene. Among these, 1,3-butadiene, isoprene and 1,3-pentadiene are preferable, and 1,3-butadiene is more preferable from the viewpoint of obtaining a heat storage material and a heat storage microcapsule excellent in availability and physical properties. In addition, a conjugated diene compound may be used individually by 1 type, and may use 2 or more types together.

The structural unit (a-1) is preferably a structural unit containing 95 to 100% by mass of a structural unit derived from 1,3-butadiene, and is a structural unit composed only of a structural unit derived from 1,3-butadiene. It is particularly preferred.

The content ratio of the structural unit (a-1) in the polymer block (A) is 95% by mass or more based on the polymer block (A) from the viewpoint of maintaining fluidity during the molding process of the heat storage material and the heat storage microcapsule. The polymer block (A) is more preferably composed of only the structural unit (a-1).

The vinyl bond content in the polymer block (A) is less than 30 mol%, preferably less than 20 mol%, more preferably from the viewpoint of maintaining shape retention when the heat storage material and the heat storage microcapsule are formed. Is 18 mol% or less. The lower limit of the vinyl bond content in the polymer block (A) is not particularly limited.

In the present specification, the vinyl bond content is a conjugated diene compound incorporated in a polymer block before hydrogenation in a 1,2-bond, 3,4-bond and 1,4-bond bond mode. Of these, the total ratio (based on mol%) of those incorporated by 1,2-bonds and 3,4-bonds.

(2) Polymer block (B)
The polymer block (B) is a polymer block containing the structural unit (b-1) derived from the conjugated diene compound, and has an effect of imparting softening to the heat storage material and the heat storage microcapsule, or the polymer block From the viewpoint of preventing crystallization of (B), it may be a polymer block further comprising a structural unit derived from an alkenyl aromatic compound (hereinafter also referred to as “structural unit (b-2)”).

As this conjugated diene compound, for example, compounds similar to the conjugated diene compounds listed in the structural unit (a-1) can be used, and preferred compounds are also the same. The conjugated diene compounds in the structural units (a-1) and (b-1) may be the same or different.

The structural unit (b-1) is preferably a structural unit containing a total of 95 to 100% by mass of structural units derived from 1,3-butadiene and / or isoprene, and includes 1,3-butadiene and / or isoprene. More preferably, it is a structural unit consisting only of the derived structural unit.

The content ratio of the structural unit (b-1) in the polymer block (B) is preferably 50% by mass or more, more preferably 70% by mass or more, and particularly preferably 80% by mass or more with respect to the polymer block (B). .

When the polymer block (B) further contains the structural unit (b-2), the content ratio of the structural unit (b-2) is heavy from the viewpoint of maintaining fluidity during the molding process of the heat storage material and the heat storage microcapsule. It is preferable that it is 50 mass% or less with respect to a unification block (B).

The mass ratio of the structural unit (b-1) / structural unit (b-2) in the polymer block (B) is preferably 100/0 to 50/50, more preferably 100/0 to 70/30, and even more preferably. Is 100/0 to 80/20.

Examples of the alkenyl aromatic compound include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, N, N-diethyl-p-aminostyrene, and vinylpyridine. Among these, styrene and α-methylstyrene are preferable from the viewpoint of availability and ease of polymerization.

In the case where the polymer block (B) is a copolymer block containing the structural unit (b-1) and the structural unit (b-2), the distribution of the structural unit (b-1) is random, tapered ( The structural unit (b-1) increases or decreases along the molecular chain), a partial block shape, or any combination thereof.

The vinyl bond content in the polymer block (B) is 30 to 95 mol%, preferably 30 to 85 mol%, more preferably 40 to 75 mol%. From the viewpoint of preventing bleeding of the heat storage material when the heat storage material and the heat storage microcapsule are formed, the vinyl bond content in the polymer block (B) is preferably 30 mol% or more.

(3) Polymer block (C)
The polymer block (C) is a polymer block containing more than 50% by mass of the structural unit (c-1) derived from the alkenyl aromatic compound, and preferably a polymer block consisting of only the structural unit (c-1). It is a coalesced block. Examples of the alkenyl aromatic compound in the structural unit (c-1) include the same compounds as the alkenyl aromatic compound in the structural unit (b-2), and preferred compounds are also the same.

(4) Block configuration When the block (co) polymer does not have the polymer block (C), in the block (co) polymer, the mass conversion of the polymer block (A) and the polymer block (B) The ratio ((A) / (B)) is usually 5/95 to 50/50, preferably 10/90 to 40/60. From the viewpoint of ensuring shape retention when the heat storage material and the heat storage microcapsules are formed, the ratio of the polymer block (A) is preferably 5 or more and the ratio of the polymer block (B) is 95 or less. On the other hand, from the viewpoint of preventing bleeding of the heat storage material when the heat storage material and the heat storage microcapsule are formed, the ratio of the polymer block (A) is 50 or less, and the ratio of the polymer block (B) is 50 or more. preferable.

Next, when the block (co) polymer has the polymer block (C) and does not have the polymer block (C) at both ends, the polymer block (A) and the polymer block (B) The mass conversion ratio ({(A) + (B)} / (C)) with the polymer block (C) is usually 80/20 to 99/1, preferably 85/15 to 95/5. is there. The ratio of the polymer block (C) is preferably 20 or less from the viewpoint of maintaining the workability during melting (fluidity during molding).

Further, when the block (co) polymer has a polymer block (C) at both ends, the polymer block (A) and the ratio in terms of mass of the polymer block (B) and the polymer block (C) (A ) / (B) / (C) is usually from 0/80/20 to 49.5 / 49.5 / 1. The ratio of the polymer block (C) is preferably 20% by mass or less from the viewpoint of maintaining the workability during melting (fluidity during molding).

In the block (co) polymer, the content ratio of the structural unit derived from the alkenyl aromatic compound is 20 with respect to the block (co) polymer from the viewpoint of maintaining fluidity during the molding process of the heat storage material and the heat storage microcapsule. It is preferable that it is mass% or less, and it is more preferable that it is 15 mass% or less. Here, the content ratio of the structural unit derived from the alkenyl aromatic compound is, for example, that of the structural unit (b-2) in the polymer block (B) and the structural unit (c-1) in the polymer block (C). Refers to the total content (of course, either may not be included).

The structure of the block (co) polymer in the hydrogenated conjugated diene (co) polymer may be any as long as it satisfies the above requirements. For example, the structure represented by the following structural formulas (1) to (8) Is mentioned.

Structural formula (1): (AB) n1
Structural formula (2): (AB) n2-A
Structural formula (3): (BA) n3-B
Structural formula (4): (ABC) n4
Structural formula (5): A- (BC) n5
Structural formula (6): (AB) n6-C
Structural formula (7): (CBC) n7
Structural formula (8): (CB) n8
In structural formulas (1) to (8), A represents a polymer block (A), B represents a polymer block (B), C represents a polymer block (C), and n1 to n8 are 1 or more. Indicates an integer.

Here, in the block (co) polymer represented by the structural formulas (1) to (8), at least one of the polymer block (A), the polymer block (B), and the polymer block (C) is present. When two or more are present, each polymer block may be the same or different.

In addition, the structure of the block (co) polymer is such that the (co) polymer block extends or is coupled via a coupling agent residue as in the structures represented by the following structural formulas (9) to (15). It may be branched.

Structural formula (9): (AB) mX
Structural formula (10): (BA) mX
Structural formula (11): (ABA) mX
Structural formula (12): (BAB) mX
Structural formula (13): (ABC) mX
Structural formula (14): (ABC) X (CB)
Structural formula (15): (CB) mX
In structural formulas (9) to (15), A represents a polymer block (A), B represents a polymer block (B), C represents a polymer block (C), and m represents an integer of 2 or more. And X represents a coupling agent residue.

Among the structures represented by the structural formulas (1) to (15), the structure of the block (co) polymer is represented by the structural formula (1), (2), (3), (4) or (9). The structure represented is preferred.

The coupling rate in the block (co) polymer is preferably 50 to 90% in consideration of processability and bleeding properties of the heat storage material. In addition, let the ratio by which a molecule | numerator is connected through a coupling agent be a coupling rate.

Examples of the coupling agent include 1,2-dibromoethane, methyldichlorosilane, dimethyldichlorosilane, trichlorosilane, methyltrichlorosilane, tetrachlorosilane, tetramethoxysilane, divinylbenzene, diethyl adipate, dioctyl adipate, benzene- 1,2,4-triisocyanate, tolylene diisocyanate, epoxidized 1,2-polybutadiene, epoxidized linseed oil, tetrachlorogermanium, tetrachlorotin, butyltrichlorotin, butyltrichlorosilane, dimethylchlorosilane, 1,4 -Chloromethylbenzene, bis (trichlorosilyl) ethane.

As the block (co) polymer, the above block (co) polymers can be used alone, or two or more block (co) polymers can be mixed and used. Examples of combinations of block (co) polymers include: ABA / AB, (AB) 2-X / AB, (AB) 4-X / AB, ( AB) 4-X / (AB) 2-X / AB, (AB) 4-X / (AB) 3-X / (AB) 2-X / A- B, ABC / AB, (ABC) 2 / AB, (ABC) 2-X / AB, CBC / AB ( However, A shows a polymer block (A), B shows a polymer block (B), C shows a polymer block (C), X shows a coupling agent residue.

In addition, a block (co) polymer can be manufactured by the method of patent 3134504 and patent 3360411, for example.

[Physical properties of hydrogenated conjugated diene (co) polymer]
The hydrogenated conjugated diene (co) polymer has a polystyrene equivalent weight average molecular weight (hereinafter also referred to as “Mw”) of preferably 10,000 to 700,000, more preferably 100,000 to 500,000. Particularly preferred is 200,000 to 500,000. In order to obtain the required mechanical properties, Mw is preferably equal to or greater than the lower limit, and in order to ensure fluidity during processing, Mw is preferably equal to or less than the upper limit.

The hydrogenated conjugated diene (co) polymer preferably has a melting point measured by differential scanning calorimetry (DSC method) in the range of 70 to 140 ° C., more preferably in the range of 80 to 120 ° C. preferable. In the present specification, the melting point of the hydrogenated conjugated diene (co) polymer corresponds to Tim when measured according to JIS K-7121.

The value of the melt flow rate (hereinafter also referred to as “MFR”) of the hydrogenated conjugated diene (co) polymer is not particularly limited, but is generally preferably 0.01 to 100 g / 10 min. In the present specification, the MFR of the hydrogenated conjugated diene (co) polymer is a value measured under a load of 230 ° C. and 10 kg in accordance with JIS K-7210.

The hydrogenated conjugated diene (co) polymer can be used alone, or two or more hydrogenated conjugated diene (co) polymers can be mixed and used. Examples of combinations of hydrogenated conjugated diene (co) polymers include: ABA hydrogenated product / AB hydrogenated product, (AB) 2-X hydrogenated product / AB Hydrogenated product, (AB) 4-X hydrogenated product / AB hydrogenated product, (AB) 4-X hydrogenated product / (AB) 2-X hydrogenated product / AB hydrogenated product, (AB) 4-X hydrogenated product / (AB) 3-X hydrogenated product / (AB) 2-X hydrogenated product / A -B hydrogenated product, ABC-hydrogenated product / AB hydrogenated product, (ABBC) 2 hydrogenated product / AB hydrogenated product, (AB -C) 2-X hydrogenated product / AB hydrogenated product, CBC hydrogenated product / AB hydrogenated product (where A represents a polymer block (A), B represents a polymer block (B), C represents a polymer block (C), and X represents a coupling agent residue.

As described above, the structure of the block (co) polymer is preferably a structure represented by the structural formula (1), (2), (3), (4) or (9). Since the polymer block (A) is a polymer block having a vinyl bond content of less than 30 mol%, it becomes a polymer block having a good crystallinity and having a structure similar to polyethylene by hydrogenation. Since the polymer block (B) is a polymer block having a vinyl bond content of 30 to 95 mol%, the polymer block (B) can be converted into, for example, a conjugated diene compound in the structural unit (b-1) by hydrogenation. Is 1,3-butadiene, it has a structure similar to that of a rubber-like ethylene-butylene (co) polymer and becomes a soft polymer block. From such a viewpoint, the block (co) polymer has at least a polymer block (A) and a polymer block (B), and at least one terminal is a polymer block (A). It is more preferable that the polymer block (A) is present at both ends and the polymer block (B) is present in the middle.

Further, when the conjugated diene compound in the structural units (a-1) and (b-1) is 1,3-butadiene, it has a structure similar to an olefin crystal-ethylene / butylene-olefin crystal block polymer structure. By using a hydrogenated conjugated diene (co) polymer with such a structure, it has good affinity with the heat storage material, and together with the heat storage material, the heat storage material forms a dispersoid, and the heat storage microcapsule forms a core material. Even when the phase change is repeated, it is possible to obtain a heat storage material that maintains a stable particle size and a heat storage microcapsule that maintains a stable particle size.

[Method for producing hydrogenated conjugated diene (co) polymer]
The production method of the hydrogenated conjugated diene (co) polymer is not particularly limited, and the block (co) polymer may be produced by hydrogenating the prepared block (co) polymer. it can. The block (co) polymer is obtained, for example, by subjecting the conjugated diene compound in the structural unit (a-1) to living anion polymerization in an inert organic solvent using an organic alkali metal compound as a polymerization initiator, and then the structural unit (b-1). It can be prepared by further adding a conjugated diene compound and optionally an alkenyl aromatic compound and performing living anionic polymerization.

Examples of the inert organic solvent include aliphatic hydrocarbon solvents such as pentane, hexane, heptane, and octane; alicyclic hydrocarbon solvents such as cyclopentane, methylcyclopentane, cyclohexane, and methylcyclohexane; benzene, xylene, toluene, An aromatic hydrocarbon solvent such as ethylbenzene can be used.

When a coupling agent residue is introduced into the block (co) polymer, the coupling agent is used without performing an operation such as isolation after living anion polymerization of the conjugated diene compound in the structural unit (b-1). In addition, it can be easily introduced by reacting.

In living anionic polymerization, the vinyl bond content of polymer block (A) and polymer block (B) is combined with ether compounds, tertiary amines, alkoxides of alkali metals (sodium, potassium, etc.), phenoxides, sulfonates, etc. And it can control easily by selecting the kind, usage-amount, etc. suitably.

A hydrogenated conjugated diene (co) polymer can be easily prepared by hydrogenating this block (co) polymer. There are no particular limitations on the hydrogenation method and reaction conditions of the block (co) polymer, and it is usually carried out in the presence of a hydrogenation catalyst at 20 to 150 ° C. under a hydrogen pressure of 0.1 to 10 MPa. In this case, the hydrogenation rate can be arbitrarily selected by changing the amount of the hydrogenation catalyst, the hydrogen pressure during the hydrogenation reaction, or the reaction time.

Examples of the hydrogenation catalyst include JP-A-1-275605, JP-A-5-271326, JP-A-5-271325, JP-A-5-222115, JP-A-11-292924, and JP-A-11-292924. As described in JP 2000-37632 A, JP 59-133203 A, JP 62-218403 A, JP 7-90017 A, JP 43-19960 A, and JP 47-40473 A. A hydrogenation catalyst is mentioned. In addition, the said hydrogenation catalyst may be used only 1 type, and can also use 2 or more types together.

The hydrogenation rate of the double bond derived from the conjugated diene compound (including the conjugated diene compound in the structural units (a-1) and (b-1)) in the hydrogenated conjugated diene (co) polymer is determined by shape retention and In order to satisfy the mechanical properties, 90% or more is preferable, and 95% or more is more preferable.

After hydrogenation, if necessary, the catalyst residue is removed, or a phenol-based or amine-based anti-aging agent is added, and then the hydrogenated conjugated diene (co) polymer solution is added to the hydrogenated conjugated diene (co). The polymer is isolated. Isolation of the hydrogenated conjugated diene (co) polymer can be carried out, for example, by adding acetone or alcohol to the hydrogenated conjugated diene (co) polymer solution and precipitating, or by adding the hydrogenated conjugated diene (co) polymer solution to hot water. It is carried out by, for example, a method in which the solvent is distilled off while stirring and a method in which a hydrogenated conjugated diene (co) polymer solution in which an appropriate amount of a heat storage material is mixed in advance is poured into hot water with stirring and the solvent is distilled off. be able to.

<Other components in heat storage materials and emulsion-type heat storage materials>
Other components that can be used in the heat storage material and emulsion type heat storage material of the present invention will be described below.

The heat storage material and emulsion-type heat storage material of the present invention are for the purpose of imparting functions according to the application, anti-aging agents, antioxidants, antistatic agents, weathering agents, ultraviolet absorbers, flame retardants, antibacterial / You may contain other components, such as a fungicide, a dispersing agent, a coloring inhibitor, a rust inhibitor, a thickener, and a specific gravity adjuster, in the range which does not impair the effect of the present invention.

The heat storage material and emulsion-type heat storage material of the present invention can further contain a crystal nucleating agent (nucleating agent) for the purpose of facilitating the phase change of the heat storage material. A more preferable form is to contain a nucleating agent in the heat storage material, and it is preferable to add the nucleating agent to the heat storage material and dissolve and mix them.

The nucleating agent only needs to be a substance that can become a crystal nucleus when the heat storage material solidifies, but is preferably a material having a crystal structure similar to that of the heat storage material, and has a higher melting point than the heat storage material. A substance that causes coagulation is preferred. More preferably, the nucleating agent is a substance having a phase change temperature that is 10 to 100 ° C. higher than the melting point of the heat storage substance.

The amount of the crystal nucleating agent added is preferably 0.5 to 20 parts by mass, more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the heat storage material. From the viewpoint of sufficiently solidifying the heat storage material, the lower limit value or higher is preferable, and from the viewpoint of clarifying the heat storage temperature region due to latent heat, the lower limit value or lower is preferable.

The emulsion-type heat storage material of the present invention can further contain a supercooling inhibitor for the purpose of lowering the melting point (freezing point) of the dispersion medium. When a hydrophilic substance is used as the supercooling preventive agent, any can be used as long as it does not destabilize the emulsion by reacting with a surfactant or the like. As the hydrophilic substance, non-electrolyte and electrolyte substances can be used.

The amount of the supercooling inhibitor added is not particularly limited, but it is preferably added so that the melting point when water is added is -2 ° C to -15 ° C. By using the supercooling preventive agent, in the industrially useful temperature range of 0 ° C. to room temperature, the dispersion medium can be a heat storage material having a freezing point lower than that of the dispersoid. However, a heat storage material that does not impair the fluidity of the emulsion can be obtained.

Examples of non-electrolytic hydrophilic substances include urea.

As the electrolyte-based hydrophilic substance, a cryogen represented by general electrolyte salts can be used, and examples thereof include sodium chloride, calcium chloride, magnesium chloride, and ammonium nitrate. Particularly preferred is a non-electrolyte system having low reactivity with an ionic surfactant.

Since the emulsion-type heat storage material of the present invention uses a surfactant, bubbles may be easily generated during use. In this case, it is preferable to add an antifoaming agent to the emulsion type heat storage material. A known material can be used as the antifoaming agent. The addition amount of the antifoaming agent is preferably 0.1 to 20 parts by mass with respect to 100 parts by mass of the heat storage material excluding the antifoaming agent.

<Other components in thermal storage microcapsules>
Other components that can be used in the heat storage microcapsule of the present invention will be described below.

The heat storage microcapsule of the present invention may contain a filler as another component. Examples of fillers include colorants such as titanium oxide and carbon black, metal powders such as ferrite, inorganic fibers such as glass fibers and metal fibers, organic fibers such as carbon fibers and aramid fibers, aluminum nitride, boron nitride, and hydroxide. Heat transfer agents such as aluminum, alumina, magnesium oxide, carbon nanotubes, expanded graphite, glass beads, glass balloons, glass flakes, glass fibers, asbestos, calcium carbonate, magnesium carbonate, potassium titanate whiskers, zinc oxide whiskers, etc. Examples include fillers such as whisker, talc, silica, calcium silicate, kaolin, diatomaceous earth, montmorillonite, graphite, pumice, evo powder, cotton flock, cork powder, barium sulfate, and fluororesin. From the viewpoint of heat conductivity, carbon fiber and expanded graphite are preferable. These may be used alone or in combination of two or more.

The filler content varies depending on the purpose of the function to be imparted and the type of filler, but from the viewpoint of maintaining the fillability during processing, the content that allows the core material to maintain fluidity above the melting point of the elastomer It is desirable that Specifically, the content of the filler is preferably 0.01 to 50% by mass, more preferably 0.1 to 40% by mass with respect to 100% by mass of the core substance, and 1 to 30%. Mass% is particularly preferred. From the viewpoint of imparting the desired function to the heat storage material, 1% by mass or more is particularly preferable, and from the viewpoint of maintaining fluidity, 30% by mass or less is particularly preferable.

In addition, the heat storage microcapsules of the present invention are anti-aging agents, antioxidants, antistatic agents, weathering agents, ultraviolet absorbers, flame retardants, antibacterial / antifungal agents, antiblocking agents, dispersants, and coloring prevention. You may contain other components, such as an agent, a rust preventive agent, a specific gravity regulator, a thickening stabilizer, an antifreezing agent, and a preservative. These may be used alone or in combination of two or more.

Also, a crystal nucleating agent (nucleating agent) can be added for the purpose of facilitating the phase change of the heat storage material. A more preferable form is to add a nucleating agent to the heat storage material, and it is preferable to add to the heat storage material and dissolve and mix it. The nucleating agent may be any material that can become a crystal nucleus when the heat storage material is solidified, and examples thereof include graphite and carbon fiber.

The amount of the crystal nucleating agent added is preferably 0.5 to 20 parts by mass, more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the heat storage material. From the viewpoint of sufficiently solidifying the heat storage material, 0.5 part by mass or more is preferable, and from the viewpoint of clarifying the heat storage temperature region due to latent heat, it is preferably 20 parts by mass or less.

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples. In the examples and comparative examples, “parts” and “%” are based on mass unless otherwise specified.

The measurement methods for various physical properties and the evaluation methods for various properties are shown below.

<Physical properties of elastomers such as hydrogenated conjugated diene (co) polymers>
[Ratio (%) of polymer blocks (A) to (C)]
The mass of each polymer block relative to the total mass of the polymer block (A), the polymer block (B) and the polymer block (C) is determined from the amount of raw materials used when preparing the block (co) polymer. Calculated as a ratio.

[Vinyl bond content (mol%) of polymer blocks (A) and (B)]
Using the infrared analysis method, the vinyl bond content (mol%) of the polymer blocks (A) and (B) was calculated by the Hampton method.

[Weight average molecular weight]
Using gel permeation chromatography (GPC, trade name: HLC-8120GPC, manufactured by Tosoh Finechem Corporation, column: manufactured by Tosoh Corporation, GMH-XL), the weight average molecular weight was determined in terms of polystyrene.

[Coupling rate (%)]
The waveform obtained by the above-mentioned gel permeation chromatography measurement was separated into waveforms, and the coupling rate was calculated from the area ratio of the waveforms.

[Hydrogen addition rate (%)]
Using a carbon tetrachloride solution, the hydrogenation rate (%) was calculated from a 270 MHz, ¹ H-NMR spectrum.

[MFR (g / 10 min)]
Based on JIS K-7210, MFR (g / 10 min) was measured at 230 ° C. and 10 kg load.

[Melting point (° C)]
In accordance with JIS K-7121, the sample was held at 200 ° C. for 10 minutes using a differential scanning calorimeter (DSC), then cooled to −80 ° C. at a rate of 10 ° C./minute, and then at −80 ° C. After holding for 10 minutes, the extrapolation melting start temperature (Tim) at the crystal melting peak when the temperature was raised at a rate of 10 ° C./min was defined as the melting point (° C.).

<Physical properties and properties of heat storage materials>
[Measurement of melting point (° C.), freezing point (° C.), latent heat (kJ / kg) of emulsion composition]
The melting point, freezing point, and latent heat amount of the emulsion composition were measured using a differential scanning calorimeter (DSC). The measurement was carried out by holding the sample at 40 ° C. for 10 minutes, cooling to −20 ° C. at a rate of 10 ° C./minute, then holding at −20 ° C. for 10 minutes and then increasing to 50 ° C. at a rate of 10 ° C./minute. It went by the method of heating. In accordance with JIS K-7121, the extrapolation melting start temperature of the melting peak corresponding to the blended paraffin compound is taken as the melting point of the emulsion composition, and the extrapolation crystallization of the crystallization peak corresponding to the blended paraffin compound is started. The temperature was taken as the freezing point of the emulsion composition. The amount of heat of fusion was defined as the amount of latent heat of the emulsion composition. However, when the melting peak of water overlaps with the melting peak of the paraffin compound, the heat of solidification of the crystallization peak corresponding to the paraffin compound was used as the latent heat of the emulsion composition.

Note that the melting point of the heat storage material having a plurality of melting peaks was the extrapolated melting start temperature of the melting peak having a larger melting heat amount, and the latent heat amount was the melting heat amount of the melting peak. When there were multi-peaks and individual melting peaks could not be distinguished, they were treated as one melting peak.

[Observation of state of emulsion composition]
The state of emulsion oil droplets was visually observed using a digital microscope VHX-900 (manufactured by Keyence Corporation). The emulsion particles were dispersed in a spherical shape, and the average particle diameter was measured and the stability was evaluated.

[Measurement of average particle size of oil droplets]
The average particle size (volume average particle size) of the oil droplets was measured by appropriately diluting the obtained emulsion with ultrapure water using a laser diffraction / scattering particle size analyzer. Nanotrac UPA-EX150 (Nikkiso Co., Ltd.) was used when the particle diameter was less than 5 μm, and Microtrac MT3000 (Nikkiso Co., Ltd.) was used when the particle diameter was 5 μm or more. In addition, the dispersion medium: water refractive index 1.33, dispersoid: paraffin refractive index 1.48, and the average value of the values obtained by three measurements was defined as the average particle diameter.

[Evaluation of stability of emulsion composition]
Each emulsion was filled to a height of 50 mm in a test tube, and then sealed and left in an incubator maintained at 30 ° C. for 1 month to examine changes. The stability of the emulsion was evaluated according to the following criteria.

· AA: A product whose separation could not be confirmed visually was evaluated as a non-defective product.

BB: A product that can be visually confirmed to be separated was evaluated as a defective product.

<Physical properties and properties of thermal storage microcapsules>
[Measurement of average particle size]
The average particle diameter (volume average particle diameter) was measured by appropriately diluting the obtained microcapsules with ultrapure water using a laser diffraction / scattering particle size analyzer. Nanotrac UPA-EX150 (Nikkiso Co., Ltd.) was used when the particle diameter was less than 5 μm, and Microtrac MT3000 (Nikkiso Co., Ltd.) was used when the particle diameter was 5 μm or more. In addition, the dispersion medium: water refractive index 1.33, dispersoid: paraffin refractive index 1.48, and the average value of the values obtained by three measurements was defined as the average particle diameter.

[Heat storage material ratio]
The amount of latent heat derived from the heat storage material in the heat storage microcapsule (latent heat amount 1), and the amount of latent heat derived from the same heat storage material as the heat storage material of the same mass as the heat storage microcapsule (latent heat amount 2) It was measured. From the value obtained by dividing the amount of latent heat 1 by the amount of latent heat 2, the ratio of the heat storage material in the heat storage microcapsules was calculated. The amount of latent heat is measured using a differential scanning calorimeter. The dry heat storage microcapsules are held at 40 ° C. for 10 minutes, then cooled to −20 ° C. at a rate of 10 ° C./minute, and then to −20 ° C. After holding for 10 minutes, the temperature was raised to 100 ° C. at a rate of 10 ° C./min. According to JIS K-7121, the extrapolated melting start temperature of the melting peak corresponding to the blended heat storage material is taken as the melting point of the heat storage material, and the extrapolated crystallization start temperature of the crystallization peak corresponding to the blended heat storage material Was the freezing point of the heat storage material. The amount of heat of fusion was defined as the amount of latent heat of the heat storage material, which was defined as the amount of latent heat 1. Similarly, the latent heat amount of the heat storage material having the same mass as the heat storage microcapsule was measured, and this was defined as the latent heat amount 2.

[Evaluation of heat storage material weight loss]
The mechanical stability of the heat storage microcapsules obtained in Examples and Comparative Examples was evaluated by the following method. 20 parts of heat storage microcapsules shown in the following examples and comparative examples were dispersed in 80 parts of ion-exchanged water. 10 kg of this dispersion was continuously circulated at room temperature using a rotary magnet pump with a discharge volume of 20 liters per minute (168 hours (average number of passes in the pump: about 20000)), and 100 g of the resulting dispersion was sampled. did. The sample and 50 g of hexane were mixed with stirring, and the mass of the effluent material was quantified by gas chromatography to calculate the heat storage material loss. The weight loss of the heat storage material was indicated by the mass ratio of the heat storage material that flowed out due to the destruction of the solid mass of the heat storage microcapsule.

[Synthesis Example 1] Preparation of Hydrogenated Conjugated Diene (Co) polymer (H-1) In a reaction vessel having an internal volume of 50 L purged with nitrogen, 24000 g of cyclohexane, 1.3 g of tetrahydrofuran, 570 g of 1,3-butadiene, and n -2.4 g of butyl lithium was added and polymerization was carried out at a polymerization initiation temperature of 70 ° C. After completion of the reaction, the temperature was set to 35 ° C., 210 g of tetrahydrofuran was added, and then adiabatic polymerization was carried out while successively adding 3230 g of 1,3-butadiene. Thereafter, 1.5 g of methyldichlorosilane was added to the system and reacted for 30 minutes to prepare a block (co) polymer.

The block (co) polymer includes a structural unit derived from 1,3-butadiene, a polymer block (A) having a vinyl bond content of 16 mol%, and a structural unit derived from 1,3-butadiene. And a block (co) polymer having a polymer block (B) having a vinyl bond content of 58 mol%. The block (co) polymer had a weight average molecular weight of 380,000 and a coupling rate of 75%.

Subsequently, the reaction solution containing the block (co) polymer was brought to 80 ° C., 2.5 g of bis (cyclopentadienyl) titanium furfuryloxychloride and 1.2 g of n-butyllithium were added, and the hydrogen pressure was 1.0 MPa. Was allowed to react for 2 hours.

After the reaction, the reaction solution is returned to room temperature and normal pressure, extracted from the reaction vessel, stirred into water, and the solvent is removed by steam distillation to obtain the desired hydrogenated conjugated diene (co) polymer (H-1 ) The hydrogenation rate of the hydrogenated conjugated diene (co) polymer (H-1) was 98%, the MFR was 2.3 g / 10 min, and the melting point was 82.0 ° C.

[Synthesis Example 2] Preparation of Hydrogenated Conjugated Diene (Co) polymer (H-2) In Synthesis Example 1, the amount of 1,3-butadiene used in the polymerization reaction of the polymer blocks (A) and (B) was determined. The amount of n-butyllithium was changed to 900 g and 2100 g, the amount of tetrahydrofuran used for the polymerization reaction of the polymer block (B) was changed to 140 g, and tetrachlorosilane was used instead of methyldichloromethane. Except for the above, a block (co) polymer was prepared in the same manner as in Synthesis Example 1.

The block (co) polymer includes a structural unit derived from 1,3-butadiene, a polymer block (A) having a vinyl bond content of 15 mol%, and a structural unit derived from 1,3-butadiene. And a block (co) polymer having a polymer block (B) having a vinyl bond content of 51 mol%. The block (co) polymer had a weight average molecular weight of 320,000 and a coupling rate of 79%.

Subsequently, a hydrogenation reaction was carried out in the same manner as in Synthesis Example 1 to obtain the desired hydrogenated conjugated diene (co) polymer (H-2). The hydrogenation rate of the hydrogenated conjugated diene (co) polymer (H-2) was 98%, the MFR was 0.7 g / 10 min, and the melting point was 83.8 ° C.

[Emulsion type heat storage material]
[Example A1]
10 g of the hydrogenated conjugated diene (co) polymer (H-1) prepared in Synthesis Example 1, 90 g of n-hexadecane (P-1), and 4 g of polyoxyethylene stearyl ether (S-1) are made of glass. Heated to 120 ° C. in the flask and mixed for 2 hours. After the temperature of the solution was lowered to 80 ° C., 100 g of water heated to 80 ° C. was added, and the mixture was stirred with a homogenizer at 8000 rpm for 5 minutes to prepare a white emulsion. The composition ratio of each component of the obtained emulsion is shown in Table 1.

As a result of observing this emulsion with an optical microscope, oil droplets composed of hydrogenated conjugated diene (co) polymer (H-1) and n-hexadecane (P-1) were uniformly dispersed in a spherical shape in the aqueous phase. It was confirmed that The average particle size of the oil droplets was 3.4 μm.

[Examples A2 to A14, Comparative Examples A1 to A2]
An emulsion having the composition ratio shown in Table 1 was prepared in the same manner as in Example A1. In addition, it describes below about the kind of used thermal storage material, an elastomer, or a polymer (it showed as "polymer" below), surfactant, and an additive.

[Heat storage material]
P-1 ... n-hexadecane P-2 ... n-tetradecane P-3 ... n-octadecane [polymer]
H-1 ... polymer prepared in Synthesis Example 1 H-2 ... polymer prepared in Synthesis Example 2 H-3 ... SEBS: Kraton G1651 (manufactured by Kraton Polymer Japan Co., Ltd.) (weight average molecular weight: about 250,000)
H-4 ... EPDM: JSR EP103AF (manufactured by JSR Corporation)
(Weight average molecular weight: about 500,000)
H-5 ... LLDPE: Novatec LL UJ990 (manufactured by Nippon Polyethylene Co., Ltd.)
[Surfactant]
S-1 ... polyoxyethylene stearyl ether S-2 ... polyoxyethylene sorbitan monooleate [additive]
A-1: Ethylene glycol Table 1 shows the measurement results and evaluation results of the produced heat storage materials.

[Heat storage microcapsule]
[Production Example B1]
To a separable flask, 90 parts of n-tetradecane (P-1) was added and heated to 50 ° C. in an oil bath to be melted. Next, 10 parts of hydrogenated conjugated diene copolymer (H-1) was added, heated to 85 ° C. in an oil bath, stirred for 3 hours and dissolved in n-tetradecane, and the core material (C-1). Got.

[Production Examples B2 to B16]
Core materials C-2 to C-16 were obtained in the same manner as in Production Example B1, except that in Production Example B1, the types and blending amounts of the heat storage material and elastomer were as shown in Table 2. The types of heat storage materials and elastomers used are described below.

[Heat storage material]
P-1 ... n-tetradecane P-2 ... n-pentadecane P-3 ... n-hexadecane P-4 ... n-heptadecane P-5 ... n-octadecane P-6 ... n-icosane P-7 ... paraffin wax: HNP -9 (Nippon Seiwa Co., Ltd.)
P-8 ... 1-octadecanol P-9 ... Myristyl myristate [Elastomer]
H-1 ... polymer prepared in Synthesis Example 1 H-2 ... polymer prepared in Synthesis Example 2 H-3 ... SEBS: Kraton G1651 (manufactured by Kraton Polymer Japan Co., Ltd.)
H-4 ... EPDM: JSR EP103AF (manufactured by JSR Corporation)

[Example B1]
In a nitrogen-substituted autoclave 1, 20.6 parts of 37% formaldehyde aqueous solution and 40 parts of water are added to 16 parts of melamine powder, the pH is adjusted to 8, and the mixture is heated to about 70 ° C. and heated to about 70 ° C. Got. 100 parts of a 10% styrene maleic anhydride copolymer aqueous sodium salt solution heated to 85 ° C. and adjusted to pH 4.5 in a nitrogen-substituted autoclave 2, and a core material (C-1 70 parts were added with vigorous stirring and emulsification was carried out until the average particle size reached 3.0 μm. The total amount of the melamine-formaldehyde initial condensate aqueous solution was added to this emulsion and stirred at 85 ° C. for 2 hours, and then the pH was adjusted to 9 to obtain a heat storage microcapsule dispersion. The obtained dispersion was dried to obtain heat storage microcapsules.

[Examples B2 to B18]
In Example B1, the heat storage microcapsules were obtained in the same manner as in Example B1, except that the core substance was changed to that shown in Table 3 and emulsification was performed until the average particle size reached the value shown in Table 3. .

[Example B19]
In nitrogen-substituted autoclave 1, 40.5 parts of 37% formaldehyde aqueous solution is added to 20 parts of urea, and the pH of the reaction system is adjusted to 7.5 to 8.5 with 28% ammonia water, and then about 70 ° C. To an aqueous urea-formaldehyde precondensate aqueous solution. A core material heated to 85 ° C. in 100 parts of an aqueous sodium salt solution of a 10% styrene maleic anhydride copolymer heated to 85 ° C. and adjusted to pH 4.5 in a nitrogen-substituted autoclave 2 (C— 3) 70 parts were added with vigorous stirring and emulsification was carried out until the average particle size reached 3.0 μm. The total amount of the urea-formaldehyde initial condensate aqueous solution was added to this emulsion and stirred at 85 ° C. for 2 hours, and then the pH was adjusted to 9 to obtain a heat storage microcapsule dispersion. The obtained dispersion was dried to obtain heat storage microcapsules.

[Examples B20 to B22]
In a nitrogen-substituted autoclave 1, a predetermined amount of core material melted at 85 ° C. and a film-forming monomer were mixed and stirred, and then heated to 90 ° C., and 60% by mass of ions. A predetermined amount of sodium dodecylbenzenesulfonate dispersant was added as the exchange water and dispersant, and stirred to prepare an emulsified monomer solution. The remaining amount of ion-exchanged water was put into the autoclave 2 purged with nitrogen, and stirring was started. After depressurizing the inside of the autoclave 2 and deoxidizing the inside of the container, the pressure was returned to atmospheric pressure with nitrogen to make the inside a nitrogen atmosphere, and then the emulsified monomer solution was added all at once. After raising the temperature of the autoclave 2 to 85 ° C., a predetermined amount of benzoyl peroxide was added as an initiator to initiate polymerization. After completing the polymerization in 1 hour and then aging for 2 hours, the autoclave 2 was cooled to room temperature to obtain a heat storage microcapsule dispersion. The obtained dispersion was dried to obtain heat storage microcapsules.

Table 4 shows the amount of each component used.

[Comparative Example B1]
In a nitrogen-substituted autoclave 1, 20.6 parts of 37% formaldehyde aqueous solution and 40 parts of water are added to 16 parts of melamine powder, the pH is adjusted to 8, and the mixture is heated to about 70 ° C. and heated to about 70 ° C. Got. In an autoclave 2 purged with nitrogen, 80 parts of n-hexadecane (P-3) as a heat storage material were vigorously stirred in 100 parts of a 5% styrene maleic anhydride copolymer sodium salt adjusted to pH 4.5. While being added, the mixture was emulsified until the average particle size became 7.1 μm. The total amount of the melamine-formaldehyde initial condensate aqueous solution was added to this emulsion and stirred at 70 ° C. for 2 hours, and then the pH was adjusted to 9 to obtain a heat storage microcapsule dispersion. The obtained dispersion was dried to obtain heat storage microcapsules.

[Comparative Example B2]
In a nitrogen-substituted autoclave 1, 11.5 parts of 37% formaldehyde aqueous solution and 40 parts of water are added to 8 parts of melamine powder, the pH is adjusted to 8, and then heated to about 70 ° C. to prepare an aqueous solution of melamine formaldehyde initial condensate. Obtained. In an autoclave 2 purged with nitrogen, 80 parts of n-hexadecane (P-3) as a heat storage material were vigorously stirred in 100 parts of a 5% styrene maleic anhydride copolymer sodium salt adjusted to pH 4.5. While being added, emulsification was carried out until the average particle size became 1.8 μm. The total amount of the melamine-formaldehyde initial condensate aqueous solution was added to this emulsion and stirred at 70 ° C. for 2 hours, and then the pH was adjusted to 9 to obtain a heat storage microcapsule dispersion. The obtained dispersion was dried to obtain heat storage microcapsules.

[Comparative Example B3]
A heat storage microcapsule dispersion was obtained in the same manner as in Comparative Example B1, except that the average particle size of the heat storage microcapsules in Comparative Example B2 was set to the value shown in Table 3. The obtained dispersion was dried to obtain heat storage microcapsules.

Table 3 shows the results of measurement of the heat storage material ratio, average particle diameter, and heat storage material weight loss of the heat storage microcapsules obtained in Examples B1 to B19 and Comparative Examples B1 to B3. Table 4 shows the results of measuring the heat storage material ratio, average particle diameter, and heat storage material loss of the heat storage microcapsules obtained in Examples B20 to B22.

Claims (17)

A heat storage material in which particles containing a heat storage material and an elastomer are dispersed,
The heat storage material includes at least one selected from the group consisting of paraffin compounds, fatty acids, fatty acid ester compounds, aliphatic ethers, aliphatic ketones, and aliphatic alcohols,
Thermal storage material. The heat storage material according to claim 1, wherein the elastomer has a polystyrene-reduced weight average molecular weight of 10,000 to 700,000 as measured by a gel permeation chromatography method. At least one heat storage material selected from the group consisting of paraffin compounds, fatty acids, fatty acid ester compounds, aliphatic ethers, aliphatic ketones, and aliphatic alcohols;
An elastomer,
water and,
A heat storage material comprising an emulsion containing a surfactant. The heat storage material according to claim 3, wherein the elastomer has a polystyrene-equivalent weight average molecular weight of 10,000 to 700,000 as measured by a gel permeation chromatography method. The heat storage material according to claim 3 or 4, wherein the elastomer is a hydrogenated conjugated diene (co) polymer. The hydrogenated conjugated diene (co) polymer is
A polymer block (A) containing a structural unit (a-1) derived from a conjugated diene compound and having a vinyl bond content of less than 30 mol%,
A polymer block (B) containing a structural unit (b-1) derived from a conjugated diene compound and having a vinyl bond content of 30 to 95 mol%,
A polymer block (C) containing the structural unit (c-1) derived from the alkenyl aromatic compound in an amount of more than 50% by mass;
The heat storage material according to claim 5, which is obtained by hydrogenating a block (co) polymer having at least one polymer block selected from the group consisting of: The heat storage material according to claim 6, wherein the block (co) polymer has at least a polymer block (A) and a polymer block (B), and at least one terminal thereof is the polymer block (A). . The heat storage material according to any one of claims 3 to 7, which is an oil-in-water emulsion in which at least the heat storage material and the elastomer are dispersoids and the water is a dispersion medium. A heat storage device comprising a container filled with the heat storage material according to any one of claims 1 to 8. At least one heat storage material selected from the group consisting of paraffin compounds, fatty acids, fatty acid ester compounds, aliphatic ethers, aliphatic ketones, and aliphatic alcohols;
A core material comprising an elastomer,
Thermal storage microcapsules covered with a coating. The heat storage microcapsule according to claim 10, wherein the elastomer has a polystyrene-reduced weight average molecular weight of 10,000 to 700,000 as measured by gel permeation chromatography. The heat storage microcapsule according to claim 10 or 11, wherein the elastomer is a hydrogenated conjugated diene (co) polymer. The hydrogenated conjugated diene (co) polymer is
A polymer block (A) containing a structural unit (a-1) derived from a conjugated diene compound and having a vinyl bond content of less than 30 mol%,
A polymer block (B) containing a structural unit (b-1) derived from a conjugated diene compound and having a vinyl bond content of 30 to 95 mol%,
A polymer block (C) containing the structural unit (c-1) derived from the alkenyl aromatic compound in an amount of more than 50% by mass;
The heat storage microcapsule according to claim 12, which is obtained by hydrogenating a block (co) polymer having at least one polymer block selected from the group consisting of. The heat storage micro of claim 13, wherein the block (co) polymer has at least a polymer block (A) and a polymer block (B), and at least one terminal thereof is the polymer block (A). capsule. The film is made of melamine resin, urea resin, polystyrene resin, acrylic resin, styrene- (meth) acrylic acid ester copolymer resin, acrylonitrile-styrene copolymer resin, polyester resin, polyurethane resin, polyurea resin, and polyamide resin. The heat storage microcapsule according to any one of claims 10 to 14, which is a film made of at least one resin selected from the above. A heat storage material comprising the heat storage microcapsule according to any one of claims 10 to 15. The heat storage material according to claim 1, wherein the particles containing the heat storage material and the elastomer are the heat storage microcapsules according to any one of claims 10 to 15.