JP2007031685A - Latent heat storage material and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a latent heat storage material which can be used over a wide range of fields such as a heat insulator, a cold insulator, a heat storage building material and a latent heat storage material for a gas adsorbent and has the strength required, to provide gas adsorbent including the latent heat storage material, and to provide a method for producing the latent heat storage material. <P>SOLUTION: The latent heat storage material comprises a long shaped product having a sheath core structure, in which a component consisting of a core of the sheath core structure comprises an organic compound causing absorption and release of heat through a phase change and a thermoplastic elastomer as a main component and a component consisting of a sheath of the sheath core structure substantially comprises a thermoplastic resin. The latent heat storage material is produced by co-extruding. The gas adsorbent including the latent heat storage material and an activated charcoal is used for a gas adsorbent for a canister or the like. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a latent heat storage material that can be used in a wide range of fields as a heat insulating material, a cold insulating material, and the like, and a method for manufacturing the same.

  Latent heat storage materials that can store and release thermal energy by phase change are used in many fields such as heat storage materials for buildings and heat insulation / cooling materials for foods.

  Such latent heat storage materials are used in various forms depending on the purpose. For example, in the past, it is known to use a container or bag filled with a heat storage material for cold storage of food or the like, but in addition to this, a latent heat storage material in the form of capsules, microcapsules, fibers, etc. It has been known. For example, Patent Documents 1 and 2 describe a method for producing a heat storage material capsule including a heat storage material made of a hydrate of an inorganic acid salt such as sodium acetate or sodium phosphate in a capsule made of a thermoplastic resin. Patent Document 3 discloses a heat storage material microencapsulated by emulsion polymerization.

  The capsules or microcapsules are used by being kneaded into a material such as resin, concrete, or various wall materials, or coated on a material such as paper or film. However, such capsules or microcapsules are mechanically weak and have the disadvantage of being easily broken by pressure.

  Patent Literature 4 describes a heat storage fiber in which a latent heat storage material such as paraffin and polyolefin are mixed and a fiber obtained by melt spinning has a seepage prevention layer formed thereon. This seepage prevention layer is formed using a thermosetting resin such as a water-soluble epoxy resin emulsion. Patent Document 5 discloses a heat storage body including a core material made of high-density or low-density polyethylene and a cross-linked hydrophobic resin layer covering the core material. Such a fibrous or long latent heat storage material is considered to have a desired strength if it has a certain diameter. However, in the said patent document 4, compatibility with the fiber containing a paraffin and polyolefin, an epoxy resin, etc. is bad, and sufficient adhesiveness cannot be obtained. Further, in any of the cited documents 4 and 5, since the coating is performed using the curable resin, it lacks flexibility. When such a latent heat storage material is bent, the coating layer may be destroyed.

The latent heat storage material is also preferably used for a gas adsorbent contained in a canister of an automobile, and a latent heat storage material that can be preferably used for such a gas adsorbent is demanded. .
JP-A 63-309580 JP 63-115718 A JP 2005-54064 A Japanese Patent No. 2761094 JP-A-62-135588 JP 2001-198918 A

  The present invention solves the above-described conventional problems, and its purpose is to be easily used in a wide range of fields such as a heat insulating material, a cold insulating material, a heat storage building material, and a gas adsorbing material, and has a predetermined strength and flexibility. It is in providing the latent heat storage material which has, and its effective manufacturing method.

  The latent heat storage material of the present invention is an elongated molded body having a core-sheath structure, and the components constituting the core of the core-sheath structure are an organic compound and a thermoplastic elastomer that absorb and release heat by phase change. The component constituting the sheath of the core-sheath structure is substantially made of a thermoplastic resin, and the latent heat storage material is manufactured by coextrusion.

  In a preferred embodiment, the organic compound is an organic compound that undergoes a phase change in a temperature range of −10 ° C. to 100 ° C.

  In a preferred embodiment, the thermoplastic resin as a component constituting the sheath has a melting point of 100 ° C. or higher, a glass transition point of −30 ° C. or higher, and substantially an organic compound as a component constituting the core. It is a thermoplastic resin that is not compatible.

  In a preferred embodiment, the mass ratio of the organic compound that is the component constituting the core and the thermoplastic elastomer is 1: 1 to 9: 1, and the component that constitutes the core and the component that constitutes the sheath. Is a mass ratio of 20: 1 to 1: 1.

  In a preferred embodiment, the latent heat storage material has a heat storage capacity of 30 mJ / mg or more.

  In a preferred embodiment, the thickness of the sheath portion of the core-sheath structure is 0.01 to 1 mm.

In a preferred embodiment, the cross-sectional area of the surface perpendicular to the longitudinal direction of the elongated molded body is 0.8 to ²⁰ mm ² .

  In a preferred embodiment, the thermoplastic elastomer is an olefin elastomer or a styrene elastomer.

  In a preferred embodiment, the organic compound is at least one organic compound selected from the group consisting of hydrocarbon compounds, higher alcohols, higher fatty acids, higher fatty acid glycerides, amides, polyethylene glycols, phenols, and amines. A compound.

  The method for producing a latent heat storage material comprising a long shaped body having a core-sheath structure according to the present invention includes a step of preparing a die device having an extrusion-molded portion capable of forming a core-sheath structure; and a phase change in the die device. A material constituting a core mainly composed of an organic compound and a thermoplastic elastomer that absorbs and releases heat by the heat treatment, and a material constituting a sheath substantially composed of a thermoplastic resin in a molten state, Each of the molten materials is extruded at the same time to obtain a latent heat storage material composed of a long shaped body having a core-sheath structure in which the outer periphery of the long material composed of the material composing the core is coated with the material composing the sheath. Process.

  The latent heat storage material of the present invention is a latent heat storage material formed of a long shaped body having a core-sheath structure, and is substantially composed of an inner layer mainly composed of a heat storage organic compound and a thermoplastic elastomer, and a thermoplastic resin. And an outer layer. Therefore, it is excellent in strength and flexibility. This latent heat storage material can be wrapped around piping, embedded in wall surfaces, embedded in road paving, used in combination with other materials for desired purposes, and building materials, paving materials, It can be used in various fields such as general cold and heat insulation materials and gas adsorbents.

  In particular, the gas adsorbent containing the latent heat storage material and activated carbon does not cause classification even by vibration, unlike the conventional granular heat storage material. Therefore, it has a sufficient gas adsorption / desorption function and heat exchange function even in an environment where vibration occurs, and can be suitably used for an automobile canister or the like.

(I) Latent Heat Storage Material A component constituting the core of the latent heat storage material of the present invention (hereinafter sometimes referred to as a core component) is an organic compound (hereinafter referred to as a heat storage organic compound) that absorbs and releases heat by phase change. And a thermoplastic elastomer as a main component, and if necessary, a crystal nucleating agent, a substance for preventing a supercooling phenomenon of a heat storage organic compound, an additive, and the like.

  The heat-storing organic compound is preferably an organic compound that undergoes a phase change in a temperature range of −10 ° C. to 100 ° C., more preferably 0 to 80 ° C. Such a heat storage organic compound is appropriately selected according to the intended use of the latent heat storage material. For example, when the latent heat storage material is used as a gas adsorbent in combination with activated carbon as described later, the heat storage organic compound is preferably at a temperature of 20 ° C to 70 ° C, more preferably 30 to 65 ° C. Organic compounds that change phase in the range are used.

  The heat storage organic compound that can be used in the latent heat storage material of the present invention is not particularly limited, and examples thereof include the following compounds: hydrocarbons such as decane, dodecane, tetradecane, pentadecane, hexadecane, octadecane, eicosane, and paraffin. Compound: higher alcohols such as lauryl alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol, eicosanol, behenyl alcohol, myricyl alcohol; higher fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, behenic acid and the like Glycerides; amides such as propionamide; polyethylene glycols such as polyethylene glycol (PEG) 400, PEG600, PEG1000, PEG2000, PEG4000, PEG6000 Call the like; amines such as and ethylene diamine; phenols, phenols such as cresol. When the latent heat storage material is used as a gas adsorbent in combination with activated carbon, a C10-20 hydrocarbon compound, a C10-20 higher alcohol, and a C10-20 higher fatty acid are preferred among the above compounds. It is.

  The thermoplastic elastomer refers to a thermoplastic resin that has the same properties as an elastic vulcanized rubber and can be molded in the same manner as a normal thermoplastic resin because it has fluidity at high temperatures. This thermoplastic elastomer has a soft segment (soft phase) and a hard segment (hard phase) in the molecule, the soft segment functions as an elastic rubber part, and the hard segment prevents plastic deformation It has a molecular restraint function. The thermoplastic resin elastomer may be a single resin having the soft segment and the hard segment, or a mixture of a plurality of resins having different properties, and the soft segment and the hard segment exist as a whole. It may be in a state.

  As the thermoplastic elastomer, a single polymer or a plurality of polymers suitable for the kind of soft segment and hard segment to be contained, the molecular weight, the arrangement of repeating units of the polymer, and the like are appropriately selected according to the purpose. These elastomers may be cross-linked polymers or non-cross-linked polymers, or may be pseudo-cross-linked polymers. These thermoplastic elastomers can be broadly classified into styrene, olefin, urethane, polyester, polyamide, 1,2-polybutadiene, vinyl chloride, fluororesin, and silicone resin. . Of these, olefin elastomers or styrene elastomers are preferred.

  As the crystal nucleating agent, a compound having a melting point higher than that of the heat-storing organic compound can be used. Examples of such a high melting point compound include aliphatic hydrocarbon compounds, aromatic compounds, esters, carboxylic acids, alcohols, amides, and the like.

  Specifically, for example, when octadecane is used as a compound with phase change, it contains palmityl alcohol, stearyl alcohol, eicosanol, myristic acid, behenic acid, stearamide, ethylenebisoleic acid, etc. as a crystal nucleating agent It is suitable to make it. These high melting point compounds may be used in combination of two or more.

  Substances that prevent the supercooling phenomenon of heat-storing organic compounds (organic compounds that absorb and release heat due to phase changes) are intended to ensure that the phase changes during cooling of the compounds, that is, nucleating agents and Used for similar purposes. Examples of such compounds include fine particles of inorganic compounds such as talc, silica, titanium dioxide, calcium silicate, and antimony trioxide, and fine particles of organic acid salts such as magnesium stearate and sodium benzoate. Since polyethylene glycols have a particularly remarkable decrease in the crystallization temperature, it is preferable to add a substance for preventing these supercooling phenomena to promote crystallization.

  Additives include antioxidants, heat-storing organic compounds for improving thermal conductivity, fillers with higher thermal conductivity, plasticizers, flame retardants, antistatic agents, UV absorbers, etc. It is done. Examples of the filler having high thermal conductivity include fillers made of metals such as aluminum flakes, aluminum fibers, stainless steel foil, and stainless fibers; metal salt powders such as calcium carbonate, aluminum hydroxide, and magnesium hydroxide; talc, silica, clay , Mica, graphite, carbon fiber and the like.

  The mass ratio between the heat-storing organic compound and the thermoplastic elastomer is preferably 1: 1 to 9: 1, and more preferably 2: 1 to 8: 1. When other components (crystal nucleating agent, additive, etc.) are contained, these components are preferably contained in the core component in a proportion of 15% by mass or less.

  A component constituting the sheath of the latent heat storage material of the present invention (hereinafter sometimes referred to as a sheath component) is substantially made of a thermoplastic resin, and is added within a range that does not hinder the properties of the sheath component as necessary. Contains agents.

  The thermoplastic resin usually has a melting point of 100 ° C. or higher, a glass transition point of −30 ° C. or higher, and is substantially incompatible with the heat storage organic compound as the core component. Such thermoplastic resins are not particularly limited, and include the following compounds: polyolefins such as polyethylene and polypropylene, polyamides, and polyesters. Examples of the additive include process oil, plasticizer, lubricant, neutralizer, antioxidant, weathering agent, ultraviolet absorber, heavy metal deactivator, lubricant, nucleating agent, antistatic agent, release agent, Pigments such as pigments and dyes, antifungal agents, antibacterial agents, light stabilizers, fillers, and the like can be used.

  The mass ratio of the core component to the sheath component is preferably 20: 1 to 1: 1, and more preferably 15: 1 to 2: 1.

  The latent heat storage material of the present invention is manufactured by a general coextrusion method using the above-mentioned materials.

  For example, a die apparatus having an extrusion-molded part capable of forming a core-sheath structure, an extruder for a core material that supplies a molten material for the core to the die apparatus, and an extruder for a sheath material that supplies a molten material for the sheath prepare. The die apparatus is supplied with a melted core material (core component) and sheath material (sheath component) from the core material extruder and sheath material extruder, respectively, and performs co-extrusion. As described above, as the core material, a material mainly composed of an organic compound and a thermoplastic elastomer that absorb and release heat by phase change, and as the sheath material, a material substantially made of a thermoplastic resin is used. . Thus, each of the molten materials is extruded from the molding part at the same time, and a long shaped body having a core-sheath structure in which the outer periphery of the long material made of the material constituting the core is covered with the material constituting the sheath. Is formed.

  In order to efficiently perform the molding by the co-extrusion, a die apparatus having a plurality of the molding parts may be employed. For example, the die apparatus described in Patent Document 6 is preferably used.

In general, the latent heat storage material formed of the molded body thus obtained has a circular or substantially circular cross section. Usually, the thickness of the sheath part of the said core-sheath structure is 0.01-1 mm, Preferably it is 0.02-0.5 mm. The cross-sectional area of the surface perpendicular to the longitudinal direction of the elongated shaped body is usually 0.8 to ²⁰ mm ² , preferably 1.7 to 15 mm ² .

  The heat storage capacity of the obtained latent heat storage material is preferably 30 mJ / mg or more, and more preferably 50 mJ / mg or more.

  In order to prevent the material of the core part from flowing out, the end surface of the molded body obtained by the co-extrusion is usually sealed. For example, the end of the molded body is sealed by thermocompression bonding, or is sealed using an adhesive or the like.

(II) Gas adsorbent A gas adsorbent containing the latent heat storage material and activated carbon is preferably used.

  The mass ratio of the latent heat storage material and the activated carbon in the gas adsorbent is preferably 1:10 to 3: 7, more preferably 1: 9 to 1: 3.

  The activated carbon used for the gas adsorbent is not particularly limited. Preferably, activated carbon having a butane working capacity (hereinafter sometimes abbreviated as BWC) measured in accordance with ASTM-D5288 of 9 g / dl or more is used. The BWC of the activated carbon is more preferably 10 g / dl or more. Activated carbon having a low BWC has a low ability to adsorb evaporated fuel, and a gas adsorbent having sufficient performance may not be obtained.

  The activated carbon is usually in the form of granules, pellets, powders, etc., and preferably in the form of granules or pellets. In the case of granules, the average particle size is preferably 0.5 to 5 mm, and in the case of pellets, the diameter is preferably 1 to 4 mm and the length is preferably about 2 to 10 mm.

  Specifically, the gas adsorbent is obtained by mixing the latent heat storage material and activated carbon. Since the latent heat storage material is an elongated molded body, it can be molded into an appropriate shape according to the form of the adsorbent. For example, a planar shape such as a circle or a rectangle, or a three-dimensional shape such as a coil shape, a cube shape, or a cone shape is used, and a predetermined container is filled together with activated carbon. If necessary, the latent heat storage material and the activated carbon can be combined with a binder to be integrated.

  FIG. 1 is a schematic view showing an example of a canister (evaporative fuel collecting device) using this gas adsorbent. The canister 1 has a cylindrical canister vessel 2 having a gaseous fuel inlet 21, a gaseous fuel outlet 22, and an atmosphere opening 23, and is divided into two chambers by a partition wall 24. Air-permeable filters 61, 62, 71, and 72 are disposed on the upper and lower portions in the canister container 2. In the space between the filters 61 and 71 of the canister container, latent heat storage materials 3 and 4 are arranged and filled with activated carbon 51. The latent heat storage materials 3 and 4 are each formed in a coil shape. The coil-like latent heat storage materials 3 and 4 may be in a state of being molded, or may be in a state of being stretched or contracted in the longitudinal direction. In FIG. 1, two coil-like latent heat storage materials 3 and 4 having different diameters are each compressed in the longitudinal direction and fixed by a fixing means such as an adhesive so that the state is maintained. And it arrange | positions in the canister container 2 with the form by which the latent heat storage material 4 which is a small diameter coil was accommodated in the internal space part of the latent heat storage material 3 which is a large diameter coil. The coiled latent heat storage material fixing means may be a physical fixing means. The space between the filters 62 and 72 in the canister container is filled with activated carbon 52.

  In an automobile equipped with this canister, fuel such as gasoline that has evaporated when refueling or when the vehicle is stopped is introduced into the canister from a gas fuel inlet 21 of the canister. This gaseous fuel is adsorbed by the activated carbon 51 and then the activated carbon 52 of the gas adsorbent in the canister, and the heat generated by the adsorption is absorbed by the latent heat storage materials 3 and 4. At this time, the gaseous fuel outlet 22 is closed by a cock (not shown).

  When the engine switch of the automobile is turned on, the gaseous fuel inlet 21 is closed by a cock (not shown), and the engine side becomes negative pressure so that air flows from the atmosphere opening 23. Accordingly, the fuel adsorbed on the activated carbons 52 and 51 is desorbed from the activated carbon, flows out from the gaseous fuel outlet 22 and is introduced into the engine. At this time, the thermal energy stored in the latent heat storage material is consumed when the fuel is desorbed from the activated carbon.

  In the gas adsorbent, sufficient gas adsorption and desorption are performed, and thermal energy is efficiently absorbed and released by the latent heat storage material, thereby suppressing temperature fluctuations in the canister. Since this latent heat storage material is a long shaped product, when stored in a canister container, unlike a granular heat storage material, it is not separated from activated carbon by classification by vibration. For example, since the latent heat storage material can be formed into a desired shape such as a coil shape, the canister can be designed compactly.

  The present invention will be described below with reference to examples.

  In the following examples, comparative examples, and reference examples, the melting point, heat of fusion, temperature drop crystallization temperature, and heat of crystallization of various materials are increased using a differential scanning calorimeter (EXSTAR6000 RDC220U) manufactured by Seiko Instruments Inc. Both the temperature rate and the temperature rise rate were measured at 5 ° C./min. The heat storage capacity is shown as the average value of heat of fusion and heat of crystallization.

  BWC of activated carbon is a value measured by ASTM-D5288, and is described as BWC / ASTM in this example. The BWC of the gas adsorbent was measured by the method of Reference Example 3 based on ASTM-D5288.

(Reference Example 1)
A 350 mL plastic bottle containing tea warmed to 75 ° C. was left in a room at 25 ° C. for 1.5 hours, and then tea was drunk. The temperature of the tea was 37 ° C.

(Reference Example 2)
A 350 mL plastic bottle containing tea cooled to 7 ° C. was left in a room at 25 ° C. for 2.5 hours, and then it was not cold when drinking tea. The temperature of the tea was 15 ° C.

Example 1
20 parts by mass of an olefin elastomer (trade name: Miralastomer 3800N, manufactured by Mitsui Chemicals, Inc.) as a thermoplastic elastomer as a core component, and palmityl alcohol (trade name: Calcoal 6098, manufactured by Kao Corporation) as a heat storage organic compound as a core component. 60 parts by mass of a melting point of 48 to 51 ° C. and a heat storage capacity of 264 mJ / mg were supplied to a twin screw extruder for core material (46 mm, L / D = 37.5). 20 parts by mass of nylon (trade name: Amilan CM1017, manufactured by Toray Industries, Inc., specific gravity 1.13, melting point 225 ° C.) as a sheath component thermoplastic resin is used as a sheath material single screw extruder (40 φmm, L / D = 25). Supplied. A die device having an extrusion-molded part capable of forming a core-sheath structure at a temperature of 200 ° C. from the twin-screw extruder for core material and 240 ° C. from the single-screw extruder for sheath material (the extrusion part is concentrically formed) 6 die devices). Six extruded strands were passed through a water tank, cooled and wound up to obtain a latent heat storage material having a core-sheath structure with an outer diameter of 3.0 mm, a sheath thickness of 0.12 mm, and a heat storage capacity of 175 mJ / mg. Each of the obtained latent heat storage materials was cut into 10 m, and both ends were heat-sealed.

  One of the long latent heat storage materials was immersed in hot water and warmed. The warmed latent heat storage material was wrapped around a 350 mL PET bottle containing tea warmed to 75 ° C. and left in a room at 25 ° C. for 1.5 hours. When this tea was drunk after standing, it was sufficiently warm and the temperature of the tea was 48 ° C.

(Example 2)
Except for supplying 20 parts by mass of polypropylene (trade name: J106G, manufactured by Mitsui Chemicals, MFR = 15 at 230 ° C.) as a sheath component to a single screw extruder for sheath material (40φ mm, L / D = 25) Strands were produced in the same manner as in Example 1. The six strands thus extruded were passed through a water tank, cooled, and wound up to obtain a latent heat storage material having a core-sheath structure with an outer diameter of 3.0 mm, a sheath thickness of 0.15 mm, and a heat storage capacity of 175 mJ / mg. In the same manner as in Example 1, it was wrapped around a PET bottle and left in a room at 25 ° C. for 1.5 hours. When this tea was drunk after standing, it was sufficiently warm and the temperature of the tea was 47 ° C.

(Example 3)
A strand was produced in the same manner as in Example 1 except that a styrene elastomer (trade name: Septon 2063, manufactured by Kuraray Co., Ltd., MFR = 7 at 230 ° C.) was used as the thermoplastic elastomer of the core component. Six extruded strands were passed through a water tank, cooled and wound up to obtain a latent heat storage material having a core-sheath structure with an outer diameter of 3.0 mm, a sheath thickness of 0.12 mm, and a heat storage capacity of 175 mJ / mg. In the same manner as in Example 1, it was wrapped around a PET bottle and left in a room at 25 ° C. for 1.5 hours. When this tea was drunk after standing, it was sufficiently warm and the temperature of the tea was 47 ° C.

Example 4
20 parts by mass of an olefin-based elastomer (trade name: Miralastomer 3800N, manufactured by Mitsui Chemicals, Inc.) and a pentadecane (trade name: n-pentadecane, manufactured by Tokyo Chemical Industry Co., Ltd.), melting point 8.8 ° C., heat storage capacity A strand was prepared in the same manner as in Example 1 except that 60 parts by mass of (190 mJ / mg) was used. The six strands thus extruded were passed through a water tank, cooled, and wound up to obtain a latent heat storage material having a core-sheath structure with an outer diameter of 3.0 mm, a sheath thickness of 0.17 mm, and a heat storage capacity of 93 mJ / mg. One of the latent heat storage materials was wrapped around a 350 mL PET bottle containing tea, and the PET bottle was cooled in a refrigerator until the tea temperature reached 7 ° C. Thereafter, it was removed from the refrigerator and left in a room at 25 ° C. for 2.5 hours. When this tea was drunk after standing, it was cold enough and the tea temperature was 9 ° C.

(Example 5)
15 parts by mass of an olefin elastomer (trade name: Miralastomer 3800N, manufactured by Mitsui Chemicals, Inc.) and palmitic acid (trade name: LUNAC P-95, manufactured by Kao Corporation, melting point 60-63 ° C., heat storage capacity 270 mJ / mg) 70 mass Are fed to a twin screw extruder for core material (46 mm, L / D = 37.5), while nylon (trade name: Amilan CM1017, manufactured by Toray Industries, Inc., specific gravity 1.13, melting point 225 ° C.) 15 The mass part was supplied to a single screw extruder for sheath material (40 mm, L / D = 25). The temperature was 200 ° C. from the twin screw extruder for the core material and 180 ° C. from the single screw extruder for the sheath material, and the same die apparatus as in Example 1 was supplied. Six extruded strands were passed through a water tank, cooled and wound up to obtain a latent heat storage material having a core-sheath structure with an outer diameter of 2.0 mm, a sheath thickness of 0.05 mm, and a heat storage capacity of 185 mJ / mg. In the same manner as in Example 1, it was wrapped around a PET bottle and left in a room at 25 ° C. for 1.5 hours. When this tea was drunk after standing, it was warm enough and the temperature of the tea was 52 ° C.

(Comparative Example 1)
90 parts by mass of paraffin (trade name: Paraffin 115F, manufactured by Nippon Seiki Co., Ltd., melting point 45-50 ° C., heat storage capacity 142 mJ / mg) is supplied to a twin screw extruder for core material (46 mm, L / D = 37.5) On the other hand, 10 parts by mass of polypropylene (trade name: J106G, manufactured by Mitsui Chemicals, MFR = 15 at 230 ° C.) was supplied to a single-screw extruder for sheath material (40 mm, L / D = 25). The temperature was 80 ° C. from the twin-screw extruder for the core material, and 220 ° C. from the single-screw extruder for the sheath material, and the same die apparatus as in Example 1 was supplied. However, the difference in melt viscosity is large and the core component flows, so that a latent heat storage material having a core-sheath structure cannot be obtained.

(Comparative Example 2)
30 parts by mass of ethylene-methyl methacrylate copolymer (trade name: ACRIFT WK402, manufactured by Sumitomo Chemical Co., Ltd., MFR = 20 at 190 ° C.) and paraffin (trade name: paraffin 115F, manufactured by Nippon Seiki Co., Ltd., melting point 45-50 60 parts by mass of C., heat storage capacity 142 mJ / mg) are supplied to a twin screw extruder for core material (46 mm, L / D = 37.5), while polypropylene (trade name: J106G, manufactured by Mitsui Chemicals, 230 10 parts by mass of MFR at 15 ° C. was supplied to a single screw extruder for sheath material (40 φmm, L / D = 25). The temperature was 80 ° C. from the twin screw extruder for the core material, and 180 ° C. from the single screw extruder for the sheath material, and the same die apparatus as in Example 1 was supplied. The extruded six strands were passed through a water tank to be cooled and wound up. However, since the melt viscosity difference between the core component and the sheath component pulsated greatly, a latent heat storage material having a strand-shaped core-sheath structure could be obtained. There wasn't.

(Comparative Example 3)
20 parts by mass of an olefin-based elastomer (trade name: Miralastomer 3800N, manufactured by Mitsui Chemicals, Inc.) as a thermoplastic elastomer, and palmitic alcohol (trade name: Calcoal 6098, manufactured by Kao Corporation, melting point 48-51 ° C. as a heat storage organic compound. , Heat storage capacity 264 mJ / mg) 77 parts by mass was supplied to a twin screw extruder for core material (46 mm, L / D = 37.5) to obtain a strand-like latent heat storage material. The surface of the obtained heat storage material was coated with NBR emulsion (trade name: Nipo1 LX511A, solid content 46%, glass transition point −19 ° C.) to a dry mass of 3 parts by mass, and dried at 120 ° C. . However, organic compounds oozed out from the surface during drying and could not be completely coated.

(Comparative Example 4)
Low-density polyethylene (trade name: Sumikasen G806, manufactured by Sumitomo Chemical Co., Ltd., melting point 190 ° C., MFR = 50) 40 parts by mass, and palmitic alcohol (trade name: Calcoal 6098, manufactured by Kao Corporation, melting point) as a heat storage organic compound 48-51 ° C., heat storage capacity 264 mJ / mg) 50 parts by mass are supplied as a core component to a twin screw extruder for core material (46 φmm, L / D = 37.5), while low density polyethylene similar to the core component Ten parts by mass were supplied to a single-screw extruder for sheath material (40 mm, L / D = 25). The temperature was 110 ° C. from the twin screw extruder for the core material and 180 ° C. from the single screw extruder for the sheath material, and the same die apparatus as in Example 1 was supplied. The six strands thus extruded were passed through a water tank, cooled and wound up to obtain a latent heat storage material having a core-sheath structure with an outer diameter of 3.0 mm, a sheath thickness of 0.30 mm, and a heat storage capacity of 131 mJ / mg. When heated with hot water in the same manner as in Example 1, the organic compounds partially bleed out from the surface. After cooling, the organic compound deposited on the surface was wiped off and heated again with hot water. As a result, the organic compound bleeded out, and it was judged that it could not be used.

(Reference Example 3)
As shown in FIG. 2, a cylindrical metal canister container 20 (volume: 0.315 L) having a diameter of 7.8 cm and a height of 6.6 cm lined with a heat insulating material was prepared for the test. This container has a gaseous fuel inlet 210 at one end in the height direction and a gaseous fuel outlet 220 at the other end, and air-permeable filters 610 and 620 are arranged at upper and lower portions in the canister container 20. . As activated carbon 50, coal-based activated carbon 3GX (BWC / ASTM: 14.9 g / dl) manufactured by Kuraray Chemical Co., Ltd. was prepared, and this was filled in the space between filters 610 and 620 in the canister vessel 20 (activated carbon filling). Amount: 103 g).

  Next, 99% n-butane was supplied from the gaseous fuel inlet 210 at a flow rate of 0.315 L / min in an up flow to adsorb the n-butane. When the n-butane concentration passing through the gaseous fuel outlet 220 reached 3000 ppm, the supply of n-butane was stopped. Next, at room temperature, air was allowed to flow down through the gaseous fuel outlet 220 at a flow rate of 4.7 L / min for 20 minutes to desorb n-butane.

  This adsorption / desorption operation was repeated 10 times, and BWC was determined from the average value of the 8th to 10th n-butane adsorption amount and desorption amount. BWC was 57.8 g / L.

(Reference Example 4)
Using a wood-based activated carbon BAX1500 (BWC / ASTM: 15 g / dl) manufactured by Westbeco Co., Ltd. in a canister container in the same manner as in Reference Example 3 and measuring BWC, it was 60.0 g / L.

(Reference Example 5)
When a canister vessel was filled in the same manner as in Reference Example 3 using Pika wood activated carbon FX1135 (BWC / ASTM: 10.8 g / dl), it was 45.6 g / L.

(Example 6)
20 parts by mass of an olefin elastomer (trade name: Miralastomer 3800N, manufactured by Mitsui Chemicals, Inc.) as a thermoplastic elastomer as a core component, and palmityl alcohol (trade name: Calcoal 6098, manufactured by Kao Corporation) as a heat storage organic compound as a core component. 60 parts by mass of a melting point of 48 to 51 ° C. and a heat storage capacity of 264 mJ / mg were supplied to a twin screw extruder for core material (46 mm, L / D = 37.5). 20 parts by mass of nylon (trade name: Amilan CM1017, manufactured by Toray Industries, Inc., specific gravity 1.13, melting point 225 ° C.) as a sheath component thermoplastic resin is used as a sheath material single screw extruder (40 φmm, L / D = 25). Supplied. A die device having an extrusion-molded portion capable of forming a core-sheath structure at a temperature of 200 ° C. from the twin-screw extruder for core material and 240 ° C. from the single-screw extruder for sheath (6) To a die apparatus having one piece). Six extruded strands were passed through a water tank, cooled, and wound up to obtain a latent heat storage material having a core-sheath structure with an outer diameter of 3.0 mm, a thickness of 0.12 mm, and a heat storage capacity of 175 mJ / mg. The obtained latent heat storage material was cut into lengths of 2 m and 4 m, and both ends were heat-sealed.

  This long 2 m latent heat storage material (12 g) was wound into a cylindrical shape having a diameter of 3.6 cm and formed into a coil. A 4 m latent heat storage material (24 g) was similarly formed into a winding coil having a diameter of 6.5 cm. Each coil was compressed in the longitudinal direction and fixed with an adhesive so as to maintain its shape.

  A canister vessel 20 similar to that of Reference Example 3 was prepared, and a 6.5 cm diameter coil (latent heat storage material 30) and a 3.6 cm diameter coil (latent heat storage material) were formed in the space between the filters 610 and 620 as shown in FIG. Material 40) was placed. These coils are inserted into the cylindrical internal space of the coil that is the latent heat storage material 30 so that the longitudinal directions of the coils that are the latent heat storage material 40 are the same, and the horizontal cross sections of these coils are concentric. It mounted in the canister container 20 so that it might become. Coal-based activated carbon 3GX (BWC / ASTM: 14.9 g / dl) manufactured by Kuraray Chemical Co., Ltd. was prepared as the activated carbon 50, and this was filled in the gap between the filters 610 and 620 in the canister vessel 20 (active carbon filling amount) : 98 g). In this way, a canister 10 including a gas adsorbent made of coiled latent heat storage materials 30 and 40 and activated carbon 50 was obtained. With respect to the gas adsorbent in the canister 10, the BWC was obtained in the same manner as in Reference Example 3 and found to be 66.4 g / L. Compared to Reference Example 3, BWC was 14.9% higher.

(Example 7)
A canister was obtained in the same manner as in Example 6 except that the latent heat storage material used in Example 6 and wood activated carbon BAX1500 (BWC / ASTM: 15 g / dl) manufactured by Westbeco Corporation were used as the activated carbon. The BWC of the gas adsorbent in the canister was 67.4 g / L, and the BWC was 12.3% higher than that of Reference Example 4.

(Example 8)
A canister was obtained in the same manner as in Example 6, except that the latent heat storage material used in Example 6 and wood activated carbon FX1135 (BWC / ASTM: 10.8 g / dl) manufactured by Pika Corporation were used as the activated carbon. The BWC in the canister was 51.0 g / L, and the BWC was 11.8% higher than that in Reference Example 5.

Example 9
15 parts by mass of olefin-based elastomer (trade name: Miralastomer, manufactured by Mitsui Chemicals, Inc.) and palmitic acid (trade name: LUNAC P-95, manufactured by Kao Corporation, melting point: 60 to 63 ° C., heat storage capacity as thermoplastic elastomer of core component (270 mJ / mg) and 70 parts by mass were supplied to a twin screw extruder for core material (46 mm, L / D = 37.5). 15 parts by mass of nylon (trade name: Amilan CM1017, manufactured by Toray Industries, Inc., specific gravity 1.13, melting point 225 ° C.) as a sheath component thermoplastic resin was supplied to a single screw extruder for sheath material. The temperature was 200 ° C. from the twin screw extruder for the core material and 180 ° C. from the single screw extruder for the sheath material, and the same die apparatus as in Example 6 was supplied. Six extruded strands were passed through a water tank, cooled and wound up to obtain a latent heat storage material having a core-sheath structure with an outer diameter of 2.0 mm, a sheath thickness of 0.05 mm, and a heat storage capacity of 185 mJ / mg. The obtained latent heat storage material was cut into 3 m and 6 m, and both ends were heat-sealed.

  Each of the long 3 m latent heat storage material (8.2 g) and 6 m latent heat storage material (16.4 g) was wound up in the same manner as in Example 6 to obtain a coiled latent heat storage material. . Each coil was compressed in the same manner as in Example 6 and fixed with an adhesive or the like, and a canister was obtained in the same manner as in Example 6 using this. With respect to the gas adsorbent in the canister, the BWC was determined in the same manner as in Reference Example 3 and found to be 67.0 g / L. Compared to Reference Example 3, BWC was 15.9% higher.

(Example 10)
A strand was prepared in the same manner as in Example 6 except that a styrene elastomer (trade name: Septon 2063; manufactured by Kuraray Co., Ltd .; MFR = 7 at 230 ° C.) was used as the thermoplastic elastomer of the core component. Six extruded strands were passed through a water tank, cooled and wound up to obtain a latent heat storage material having a core-sheath structure with an outer diameter of 3.0 mm, a sheath thickness of 0.12 mm, and a heat storage capacity of 175 mJ / mg. The obtained latent heat storage material was cut into 2 m and 4 m, and both ends were heat-sealed.

  One each of the long 2 m latent heat storage material and 4 m latent heat storage material was wound up in the same manner as in Example 6 to obtain a coiled latent heat storage material. A canister was obtained in the same manner as in Example 6 except that the obtained latent heat storage material was used. With respect to the gas adsorbent in the canister, the BWC was determined in the same manner as in Reference Example 3 and found to be 66.1 g / L. Compared to Reference Example 3, BWC was 14.4% higher.

(Example 11)
50 parts by mass of an olefin elastomer (trade name: Miralastomer 3800N, manufactured by Mitsui Chemicals, Inc.) as the thermoplastic elastomer of the core component, and paraffin (trade name: paraffin 115F, manufactured by Nippon Seiki Co., Ltd.) as the heat storage organic compound of the core component 30 parts by mass of a melting point of 45 to 50 ° C. and a heat storage capacity of 142 mJ / mg were supplied to a twin screw extruder for core material (46 φmm, L / D = 37.5). 20 parts by mass of nylon (trade name: Amilan CM1017, manufactured by Toray Industries, Inc., specific gravity 1.13, melting point 225 ° C.) as a sheath component thermoplastic resin is used as a sheath material single screw extruder (40 φmm, L / D = 25). Supplied. A die device having an extrusion-molded portion capable of forming a core-sheath structure at a temperature of 200 ° C. from the twin-screw extruder for core material and 240 ° C. from the single-screw extruder for sheath (6) To a die apparatus having one piece). Six extruded strands were passed through a water tank, cooled, and wound up to obtain a latent heat storage material having a core-sheath structure with an outer diameter of 3.0 mm, a thickness of 0.12 mm, and a heat storage capacity of 43 mJ / mg. A canister was obtained in the same manner as in Example 6 except that the obtained latent heat storage material was used. The BWC of the gas adsorbent in the canister was measured and found to be 59.4 g / L. Compared with Reference Example 3, BWC was 2.8% higher.

(Comparative Example 5)
As a core component thermoplastic elastomer, 80 parts by mass of an olefin elastomer (trade name: Miralastomer 3800N, manufactured by Mitsui Chemicals, Inc.) was supplied to a twin screw extruder for core material (46 mm, L / D = 37.5). Supplying 20 parts by mass of nylon (trade name: Amilan CM1017, manufactured by Toray Industries, Inc., specific gravity 1.13, melting point 225 ° C.) as a sheath component thermoplastic resin to a sheath material single screw extruder (40 φmm, L / D = 25) did. A strand was prepared in the same manner as in Example 6 at a temperature of 200 ° C. from the twin screw extruder for the core material and 240 ° C. from the single screw extruder for the sheath. The six strands thus extruded were passed through a water bath, cooled and wound up to obtain a strand-like latent heat storage material having a core-sheath structure with an outer diameter of 3.0 mm and a sheath thickness of 0.12 mm. A canister was obtained in the same manner as in Example 6 except that the obtained latent heat storage material was used. It was 52.0 g / L when BWC was measured about the gas adsorbent in this canister. Compared to Reference Example 3, BWC was 10.0% lower.

(Comparative Example 6)
Example 6 except that 60 parts by mass of pentadecane (trade name: n-pentadecane, manufactured by Tokyo Chemical Industry Co., Ltd., melting point 8.8 ° C., heat storage capacity 190 mJ / mg) was used as the heat storage organic compound of the core component. Then, a latent heat storage material was prepared, and the obtained latent heat storage material was cut into 2 m and 4 m, and both ends of each were heat sealed.

  Using each of the long 2 m latent heat storage material (11.5 g) and 4 m latent heat storage material (23 g), it was installed in a canister vessel in the same manner as in Example 6 and was made of Kuraray Chemical Co., Ltd. Activated carbon 3GX (BWC / ASTM: 14.9 g / dl) was charged to obtain a canister. It was 55.0 g / L when BWC was measured about the gas adsorbent in this canister. Compared to Reference Example 3, BWC was reduced by 4.8%.

  The latent heat storage material of the present invention is used for heat insulation / cold insulation materials for foods, building materials requiring a heat storage function, materials for civil engineering work, heat storage materials for gas adsorbents, and the like. For example, it can be used for the following applications: food insulation / cooling material for simple use, indoor floor heating material, temperature control material in greenhouse, anti-freezing material for bridge road surface or general road, anti-freezing material for outdoor piping Air conditioning system temperature control materials, automotive canister gas adsorbents, etc.

It is a schematic diagram which shows an example of the canister using the gas adsorption material containing the latent heat storage material of this invention. It is a schematic diagram of the canister of the reference example with which the activated carbon was filled. It is a schematic diagram which shows an example of the canister using the gas adsorption material containing the latent heat storage material of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Canister 2 Canister vessel 3 Latent heat storage material 4 Latent heat storage material 10 Canister 20 Canister vessel 21 Gaseous fuel inlet 22 Gaseous fuel outlet 23 Atmospheric opening 30 Latent heat storage material 40 Latent heat storage material 50 Activated carbon 51 Activated carbon 52 Activated carbon 210 Gas fuel flow Inlet 220 Gaseous fuel outlet

Claims (10)

A latent heat storage material composed of a long shaped body having a core-sheath structure,
The components constituting the core of the core-sheath structure are mainly composed of an organic compound and a thermoplastic elastomer that absorb and release heat by phase change,
The component constituting the sheath of the core-sheath structure is substantially made of a thermoplastic resin, and is manufactured by coextrusion.
Latent heat storage material.   The latent heat storage material according to claim 1, wherein the organic compound is an organic compound that undergoes a phase change in a temperature range of -10 ° C to 100 ° C.   The thermoplastic resin that is a component constituting the sheath has a melting point of 100 ° C. or higher, a glass transition point of −30 ° C. or higher, and is substantially incompatible with the organic compound that is the component constituting the core. The latent heat storage material according to claim 1 or 2, wherein   The mass ratio of the organic compound that is the component constituting the core and the thermoplastic elastomer is 1: 1 to 9: 1, and the mass ratio of the component that constitutes the core and the component that constitutes the sheath is 20: The latent heat storage material according to any one of claims 1 to 3, wherein the latent heat storage material is 1-1: 1.   The latent heat storage material according to any one of claims 1 to 4, wherein the heat storage capacity is 30 mJ / mg or more.   The latent heat storage material according to any one of claims 1 to 5, wherein a thickness of a sheath portion of the core-sheath structure is 0.01 to 1 mm. The latent heat storage material according to any one of claims 1 to 6, wherein a cross-sectional area of a surface perpendicular to the longitudinal direction of the elongated shaped body is 0.8 to ²⁰ mm2.   The latent heat storage material according to claim 1, wherein the thermoplastic elastomer is an olefin-based elastomer or a styrene-based elastomer.   The organic compound is at least one organic compound selected from the group consisting of hydrocarbon compounds, higher alcohols, higher fatty acids, higher fatty acid glycerides, amides, polyethylene glycols, phenols, and amines. The latent heat storage material according to any one of 8. A method for producing a latent heat storage material comprising a long shaped body having a core-sheath structure,
Providing a die device having an extrusion molding part capable of forming a core-sheath structure; and constituting a core mainly composed of an organic compound and a thermoplastic elastomer that absorb and release heat by phase change in the die device. The material and the material constituting the sheath substantially composed of the thermoplastic resin are respectively supplied in a molten state, and each of the molten materials is simultaneously extruded from the molding portion, and the outer periphery of the long object made of the material constituting the core is A step of obtaining a latent heat storage material comprising a long shaped body having a core-sheath structure coated with a material constituting the sheath;
Including the method.

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