JPWO2019111358A1 - Manufacturing method of resin member, sheet, heat storage material, and resin member - Google Patents

Abstract

The present invention is, in one embodiment, a resin member containing a copolymer of ethylene and an olefin having 3 or more carbon atoms, a saturated hydrocarbon compound, and carbon fibers.

Description

The present invention relates to a resin member and a sheet using the same, a method for manufacturing the resin member, and a heat storage material and a heat control sheet using the same.

Conventionally, air-conditioning equipment in automobiles, buildings, underground streets, etc., automobile engines, electronic parts, etc. are provided with a heat storage material in order to temporarily store thermal energy and extract the thermal energy at any time.

Examples of the heat storage material include those that store heat or dissipate heat by utilizing the phase transition of a substance. As such a heat storage material, for example, a material using a saturated hydrocarbon compound is known. Saturated hydrocarbon compounds have excellent heat storage properties due to the reversible phase transition. However, the saturated hydrocarbon compound is in a liquid state on the high temperature side of the phase transition, and the saturated hydrocarbon compound may exude, so some measures must be taken to prevent exudation.

In response to such a problem, for example, Patent Document 1 discloses a heat storage material containing a styrene-ethylene-ethylene-propylene-styrene copolymer and a paraffin-based wax as a heat storage material that suppresses bleeding. There is.

Japanese Unexamined Patent Publication No. 2014-88517

By the way, the heat storage material may be used for a heat storage member such as a heat pipe. In this case, the heat storage material is required not only to have a high heat storage capacity but also to have a quick heat exchange. However, since the thermal conductivity of the heat storage material as described in Patent Document 1 is low, the heat storage material does not necessarily satisfy such a requirement.

The present invention has been made in view of such circumstances, and provides a resin member capable of suppressing exudation of a saturated hydrocarbon compound and achieving high heat storage capacity and high thermal conductivity, and a method for producing the same. The main purpose. Another object of the present invention is to provide a sheet and a heat storage material using the resin member.

The present invention is, in one embodiment, a resin member containing a copolymer of ethylene and an olefin having 3 or more carbon atoms, a saturated hydrocarbon compound, and carbon fibers.

In this resin member, the thermal conductivity of the carbon fiber may be 300 W / mK or more. The carbon number of the olefin may be 3 to 8. The melting point of the saturated hydrocarbon compound may be less than 50 ° C., and the olefin may have 8 carbon atoms. The aspect ratio of the carbon fibers may be 100 to 1000. The content of the carbon fiber may be 15% by mass or more based on the total amount of the resin member. The resin member may further contain a gelling agent. The resin member may further contain at least one selected from the group consisting of carboxylic acids and carboxylic acid metal salts.

In another aspect, the present invention is a sheet provided with a resin layer made of the above-mentioned resin member. In this sheet, the thermal conductivity of the resin layer may be 1 W / mK or more, and the heat of fusion of the resin layer may be 90 J / g or more.

In another aspect, the present invention is a heat storage material including the above resin member.

In another aspect, the present invention comprises a step of heating and melting a composition containing a copolymer of ethylene and an olefin having 3 or more carbon atoms, a saturated hydrocarbon compound, and carbon fibers. , A method for manufacturing a resin member. In this production method, the composition can be molded by injection molding, compression molding or transfer molding in the above steps.

According to the present invention, it is possible to provide a resin member capable of suppressing exudation of a saturated hydrocarbon compound and achieving high heat storage capacity and high thermal conductivity, and a method for producing the same, and the resin member is used. It becomes possible to provide a sheet and a heat storage material.

It is a schematic cross-sectional view which shows one Embodiment of a resin member.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

FIG. 1 is a schematic cross-sectional view showing an embodiment of a resin member. In one embodiment, the resin member 1 includes a copolymer of ethylene and an olefin having 3 or more carbon atoms (hereinafter, also referred to as “component (A)”) and a saturated hydrocarbon compound (hereinafter, “component (B)”). ”) And carbon fibers (hereinafter, also referred to as“ (C) component ”). The resin member 1 may be in the form of a sheet (film), for example.

The olefin (hereinafter, also simply referred to as “olefin”) constituting the component (A) has 3 or more carbon atoms, and is, for example, 3 to 8. When the olefin has 4 or more carbon atoms, the olefin may be linear or branched. Examples of the copolymer of ethylene and an olefin having 3 or more carbon atoms include a copolymer of ethylene and propylene (C3 (carbon number, the same applies hereinafter)), a copolymer of ethylene and butene (C4), and the like. Copolymer of ethylene and penten (C5), copolymer of ethylene and hexene (C6), copolymer of ethylene and heptene (C7), copolymer of ethylene and octene (C8), with ethylene Examples thereof include a copolymer of nonen (C9) and a copolymer of ethylene and decene (C10). Among these, a copolymer of ethylene and an olefin having 3 to 8 carbon atoms is preferably used because it is easily available. The copolymer of ethylene and an olefin having 3 or more carbon atoms may be used alone or in combination of two or more.

The content of the component (A) is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more based on the total amount of the resin member. The content of the component (A) is preferably 50% by mass or less, more preferably 40% by mass or less, and further preferably 30% by mass or less based on the total amount of the resin member.

The component (B) has a melting point in the range of 0 to 100 ° C., for example, from the viewpoint of obtaining a heat storage effect in a practical range. The component (B) is preferably a chain saturated hydrocarbon compound. As used herein, the term "chain" means a linear or branched chain. The component (B) is preferably linear. Specifically, the component (B) is n-tetradecane (C14 (carbon number, same below), 6 ° C (melting point, same below)), n-pentadecane (C15, 9 ° C), n-hexadecane (C16, same below). 18 ° C.), n-heptacosane (C17, 21 ° C.), n-octadecane (C18, 28 ° C.), n-nanodecane (C19, 32 ° C.), n-eicosane (C20, 37 ° C.), n-henicosane (C21, 41 ° C.), n-docosane (C22, 46 ° C.), n-tricosane (C23, 47 ° C.), n-tetracosane (C24, 50 ° C.), n-pentacosane (C25, 54 ° C.), n-hexacosane (C26, 56 ° C.), n-heptacosane (C27, 60 ° C.), n-octacosane (C28, 65 ° C.), n-nonacosane (C29, 66 ° C.), n-triacontane (C30, 67 ° C.), n-tetracontane (C30, 67 ° C.) C40, 81 ° C.), n-pentacontane (C50, 91 ° C.), n-hexacontane (C60, 98 ° C.) and the like. The melting point of the component (B) is the melting (endothermic heat) of the thermogram obtained when heated at a heating rate of 10 ° C./min using a differential scanning calorimeter (for example, "8500" manufactured by PerkinElmer Co., Ltd.). ) The temperature at the point where the tangent to the maximum slope of the peak intersects the baseline.

The component (B) may be a petroleum wax containing a linear saturated hydrocarbon compound as a main component. Petroleum wax is a refined product separated from the vacuum distillation component of petroleum or natural gas as a raw material. Specific examples of petroleum wax include Paraffin Wax (48 to 69 ° C (melting point, the same applies hereinafter)), HNP (64 to 77 ° C), SP (60 to 74 ° C), and EMW manufactured by Nippon Seiro Co., Ltd. (49 ° C.) and the like. These components (B) may be used alone or in combination of two or more.

The content of the component (B) is preferably 40% by mass or more, more preferably 45% by mass or more, and further preferably 50% by mass or more based on the total amount of the resin member. The content of the component (B) is preferably 90% by mass or less, more preferably 80% by mass or less, and further preferably 70% by mass or less based on the total amount of the resin member.

When the melting point of the saturated hydrocarbon compound is less than 50 ° C., the carbon number of the olefin in the component (A) is preferably 8 from the viewpoint of being superior in suppressing the fluidity of the saturated hydrocarbon compound.

The carbon fiber (component (C)) is defined as a fibrous (elongated) carbon material having an aspect ratio of 20 or more. The aspect ratio is the maximum length of the carbon material (fiber length) calculated from the scanning electron micrograph of the carbon material and the minimum length of the carbon material (fiber diameter) in the direction perpendicular to the direction having the maximum length. ) To (maximum length / minimum length). Since carbon fibers have a low density (specific gravity) and can be added to the resin member in a larger amount than, for example, metal fibers, it is possible to increase the heat storage amount and thermal conductivity of the resin member.

The aspect ratio of the carbon fibers is preferably 100 or more, more preferably 200 or more, still more preferably 300 or more, from the viewpoint of further increasing the contact probability between the carbon fibers and easily increasing the thermal conductivity of the resin member even with a small amount of addition. is there. The aspect ratio of the carbon fiber is preferably 1000 or less, more preferably 800 or less, still more preferably 700 or less, from the viewpoint of excellent handleability and dispersibility and stabilizing the characteristics of the resin member. From the viewpoint of achieving both of these points, the aspect ratios of the carbon fibers are preferably 100 to 1000, 100 to 800, 100 to 700, 200 to 1000, 200 to 800, 200 to 700, 300 to 1000, 300 to. 800, or 300-700.

The carbon fiber preferably has a thermal conductivity of 300 W / mK or more, more preferably 400 W / mK or more, still more preferably 500 W / mK or more, from the viewpoint of easily increasing the thermal conductivity of the resin member even with a small amount of addition. There is no upper limit to the thermal conductivity of the carbon fiber, and the higher the thermal conductivity of the carbon fiber, the higher the thermal conductivity of the resin member.

The content of the component (C) is preferably 15% by mass or more, more preferably 18% by mass or more, still more preferably 20% by mass or more, based on the total amount of the resin member, from the viewpoint of further increasing the thermal conductivity of the resin member. Is. The content of the component (C) is preferably 50% by mass or less, more preferably 40% by mass or less, still more preferably 30% by mass or less, based on the total amount of the resin member, from the viewpoint of maintaining the heat of fusion as high as possible.

The resin member 1 may further contain a gelling agent (hereinafter, also referred to as “component (D)”). The component (D) is not particularly limited as long as it is a component capable of gelling the component (B). The component (D) may be, for example, at least one selected from the group consisting of a carboxylic acid and a carboxylic acid metal salt. That is, the resin member 1 is selected from the group consisting of a copolymer of ethylene and an olefin having 3 or more carbon atoms, a saturated hydrocarbon compound, carbon fibers, a carboxylic acid, and a carboxylic acid metal salt in one embodiment. Includes at least one species.

The carboxylic acid is preferably a chain aliphatic carboxylic acid from the viewpoint of good compatibility with the saturated hydrocarbon compound. The carbon number of the carboxylic acid is preferably 10 or more, for example, 10 to 40, 10 to 30 or 10 to 25. The carboxylic acid may be saturated or unsaturated. The carboxylic acid is not particularly limited, but is, for example, lauric acid (C12 (carbon number, the same applies hereinafter)), myristic acid (C14), palmitic acid (C16), stearic acid (C18), isostearic acid (C18), docosahexaene. Acid (C22), behenic acid (C21), undecylene acid (C11), oleic acid (C18), erucic acid (C22), linoleic acid (C18), arachidonic acid (C20), linolenic acid (C18), sapienoic acid C16) and the like. The carboxylic acid may be used alone or in combination of two or more.

The carboxylic acid constituting the carboxylic acid metal salt is preferably a chain aliphatic carboxylic acid from the viewpoint of good compatibility with the saturated hydrocarbon compound (compatibility with the carboxylic acid when the carboxylic acid is used in combination). The carbon number of the carboxylic acid constituting the carboxylic acid metal salt is preferably 6 or more, for example, 6 to 30, 6 to 25, or 8 to 20. The carboxylic acid constituting the carboxylic acid metal salt may be saturated or unsaturated. The metal constituting the carboxylic acid metal salt is a metal capable of forming a salt with the carboxylic acid, and is, for example, aluminum. Specific examples of the metal carboxylate salt include aluminum stearate (C18 (carbon number, the same applies hereinafter)), aluminum laurate (C12), aluminum oleate (C18), aluminum behenate (C21), and aluminum palmitate (C21). Examples thereof include C16) and aluminum 2-ethylhexanoate (C8). The carboxylic acid metal salt may be used alone or in combination of two or more.

The content of the component (D) may be 3% by mass or more, and may be 10% by mass or less, 8% by mass or less, or 6% by mass or less based on the total amount of the resin member.

The resin member 1 may further contain a polymer having a melting point of 100 ° C. or higher (hereinafter, also referred to as “component (E)”). However, the component (E) is a component other than the copolymer (component (A)) of ethylene and an olefin having 3 or more carbon atoms. Since the resin member 1 contains the component (E), the formation of a physical mutual network structure can be expected, and the resin member 1 which is further excellent in suppressing fluidity and maintaining the shape at a high temperature (for example, 50 ° C. or higher) is obtained. can get.

The melting point of the component (E) may be 100 ° C. or higher, 120 ° C. or higher, or 140 ° C. or higher, and may be 250 ° C. or lower, 230 ° C. or lower, or 200 ° C. or lower.

It is desirable that the component (E) has good compatibility with the above-mentioned components (A) and (B). The component (E) may be, for example, polyethylene (ethylene homopolymer), polypropylene (propylene homopolymer) or the like, and is a modified polymer of polyethylene or polypropylene, ethylene or propylene, further containing a monomer unit other than ethylene or propylene. It may be a copolymer (copolymer) of and other monomers. The copolymer (copolymer) may be, for example, a block copolymer. The component (E) may be used alone or in combination of two or more.

When the melting point of the component (B) is 50 ° C. or higher, the resin member 1 is preferably polyethylene as the component (E) from the viewpoint of further excellent in suppressing fluidity and maintaining the shape in the temperature range of 50 ° C. or higher. It further comprises at least one selected from the group consisting of (ethylene homopolymer) and polypropylene (propylene homopolymer).

The content of the component (E) may be 5% by mass or more, and may be 30% by mass or less, 25% by mass or less, or 20% by mass or less based on the total amount of the resin member.

The resin member 1 may further contain other components in addition to the above components (A) to (E). Examples of other components include carbon materials other than the above-mentioned carbon fibers (for example, graphite), metal fibers, inorganic components such as glass and talc, and light absorbers that suppress light deterioration. The content of other components may be, for example, 10% by mass or less based on the total amount of the resin member.

The resin member 1 described above can be obtained, for example, by the following method. That is, in a state where the saturated hydrocarbon compound (component (B)) is heated above the melting point, the copolymer (component (A)) of ethylene and an olefin having 3 or more carbon atoms has a melting point, if necessary. A polymer (component (E)) having a temperature of 100 ° C. or higher is added and mixed uniformly. Then, if necessary, at least one selected from the group consisting of carboxylic acid and carboxylic acid metal salt (component (D)) is added, and the mixture is further uniformly mixed. Subsequently, carbon fibers (component (C)) are added and kneaded with a pressure heating press to obtain a resin member. A sheet-shaped resin member 1 can also be obtained by heating and melting this resin member and molding it. That is, the method for producing the resin member 1 is to heat and melt a composition containing the components (A) to (C) and, if necessary, the components (D), (E) and other components to form the resin member 1. It has a process (molding process). Molding in the molding step may be injection molding, compression molding or transfer molding.

Another embodiment of the present invention is a sheet including a resin layer made of a resin member 1. The sheet may be a sheet composed of only a resin layer, and may be, for example, a sheet in which a resin layer and a metal layer are laminated.

The thickness of the resin layer may be, for example, 1 to 30 mm, 2 to 20 mm, or 5 to 10 mm. The thickness of the metal layer may be, for example, 100 μm or less.

The resin layer has a high thermal conductivity. The thermal conductivity of the resin layer is preferably 1 W / mK or more, 1.1 W / mK or more, or 1.2 W / mK or more. The thermal conductivity of the resin layer is measured using a thermal conductivity meter (for example, "QTM-500" manufactured by Kyoto Electronics Industry Co., Ltd.).

The resin layer has a high heat storage capacity (heat of fusion). The heat of fusion of the resin layer is preferably 90 J / g or more, 95 J / g or more, or 100 J / g or more. The heat of fusion of the resin layer is the melting (endothermic) of the thermogram obtained when heated at a heating rate of 10 ° C./min using a differential scanning calorimeter (for example, "8500" manufactured by PerkinElmer Co., Ltd.). Calculated from the peak area.

Since the resin member 1 and the sheet using the resin member 1 can store heat or dissipate heat by utilizing the phase transition, they are suitably used as a heat storage material. That is, another embodiment of the present invention is a heat storage material including the above-mentioned resin member 1.

The heat storage material (resin member, sheet) of the present embodiment can be utilized in various fields. Heat storage materials (resin members, sheets) include, for example, air conditioning equipment (improving the efficiency of air conditioning equipment) in automobiles, buildings, public facilities, underground streets, etc., piping in factories (heat storage of piping), automobile engines (around the engine). It is used for heat retention), electronic parts (prevention of temperature rise of electronic parts), fibers of underwear, etc. Since the heat storage material (resin member, sheet) can suppress an increase in the fluidity of the component (B) and the occurrence of oozing associated therewith even at the melting point of the component (B) or higher, it can be attached to or wrapped around the object to be attached. It can be installed or installed in various states.

Although the present invention will be specifically described based on examples, the present invention is not limited to these examples.

<Examples 1 to 7>
Using the following copolymer of ethylene and an olefin having 3 or more carbon atoms, a chain saturated hydrocarbon compound, carbon fibers, and a carboxylic acid and a carboxylic acid metal salt, a resin member having the composition shown in Table 1 is prepared. Made. Specifically, in a state where the saturated hydrocarbon compound was heated to a melting point or higher, a copolymer of ethylene and an olefin having 3 or more carbon atoms was added and uniformly mixed. Then, a carboxylic acid and a carboxylic acid metal salt were added, and the mixture was further uniformly mixed. Subsequently, carbon fibers were added and kneaded with a pressure heating press (upper plate 80 ° C./lower plate 40 ° C., pressure 140 kPa) to obtain a resin member. The obtained resin member was pressurized and heated (upper and lower hot plates 80 ° C., pressurized 1 MPa) to obtain a sheet-shaped resin member having a size of 170 × 60 × 1 mm.

(Copolymer of ethylene and olefin having 3 or more carbon atoms)
A-1: Copolymer of ethylene and octene (manufactured by Dow Chemical Japan Co., Ltd., product name "ENGAGE8150")
(Chain saturated hydrocarbon compound)
B-1: n-hexadecane (melting point: 18 ° C)
(Carbon fiber)
C-1: GRANOC XN-90C-06S (manufactured by Nippon Graphite Fiber Co., Ltd., aspect ratio 600 (fiber diameter 10 μm, fiber length 6 mm), thermal conductivity 500 W / mK)
C-2: Rahima RA301 (manufactured by Teijin Limited, aspect ratio 25 (fiber diameter 8 μm, fiber length 0.2 mm), thermal conductivity 550 W / mK)
C-3: Dona Carbo S201 (manufactured by Osaka Gas Chemical Co., Ltd., aspect ratio 833 (used by cutting to a fiber diameter of 18 μm and fiber length of about 15 mm), thermal conductivity 3 W / mK)
C-4: GRANOC XN-100-03Z (manufactured by Nippon Graphite Fiber Co., Ltd., aspect ratio 300 (fiber diameter 10 μm, fiber length 3 mm), thermal conductivity 900 W / mK)
C-5: GRANOC XN-100-06Z (manufactured by Nippon Graphite Fiber Co., Ltd., aspect ratio 600 (fiber diameter 10 μm, fiber length 6 mm), thermal conductivity 900 W / mK)
(Carboxylic acid or carboxylic acid metal salt)
D-1: Aluminum 2-ethylhexanoate D-2: Oleic acid

The melting point of the saturated hydrocarbon compound was calculated from the peak temperature of melting in the heating process at a heating rate of 10 ° C./min by differential thermal analysis (DSC).

<Comparative example 1>
A resin member was obtained in the same manner as in Example 1 except that the carbon material C-6 described below was used instead of the carbon fiber.
C-6: Fine graphite (manufactured by Showa Denko KK, aspect ratio less than 20, fine powder diameter 7 μm or less)

<Comparative example 2>
A resin member was obtained in the same manner as in Example 1 except that carbon fiber was not used.

The sheet-shaped resin members of each Example and Comparative Example were evaluated as shown below. The results are shown in Table 1.

(Evaluation of exudation)
The presence or absence of liquid oozing near the melting point of each resin member was visually and tactilely determined.

(Measurement of thermal conductivity)
The thermal conductivity in the sheet surface was measured using QTM-500 (manufactured by Kyoto Electronics Industry Co., Ltd.) and PD-11N as a probe.

(Measurement of melting point, heat of fusion, freezing point and heat of solidification)
Using DSC-8500 (manufactured by PerkinElmer Co., Ltd.), the melting point and freezing point were obtained from the peak temperature of melting and the peak temperature of solidification in the heating process of 10 ° C./min, and the heat of fusion and heat of solidification were obtained from the respective areas. Was calculated. The larger the heat of fusion, the larger the heat storage capacity.

1 ... Resin member.

Claims (14)

A copolymer of ethylene and an olefin having 3 or more carbon atoms,
Saturated hydrocarbon compounds and
With carbon fiber
Resin member including. The resin member according to claim 1, wherein the carbon fiber has a thermal conductivity of 300 W / mK or more. The resin member according to claim 1 or 2, wherein the olefin has 3 to 8 carbon atoms. The resin member according to any one of claims 1 to 3, wherein the saturated hydrocarbon compound has a melting point of less than 50 ° C. and the olefin has 8 carbon atoms. The resin member according to any one of claims 1 to 4, wherein the carbon fiber has an aspect ratio of 100 to 1000. The resin member according to any one of claims 1 to 5, wherein the content of the carbon fiber is 15% by mass or more based on the total amount of the resin member. The resin member according to any one of claims 1 to 6, further comprising a gelling agent. The resin member according to any one of claims 1 to 6, further comprising at least one selected from the group consisting of a carboxylic acid and a carboxylic acid metal salt. A sheet comprising a resin layer made of the resin member according to any one of claims 1 to 8. The sheet according to claim 9, wherein the resin layer has a thermal conductivity of 1 W / mK or more. The sheet according to claim 9 or 10, wherein the heat of fusion of the resin layer is 90 J / g or more. A heat storage material comprising the resin member according to any one of claims 1 to 8. A method for producing a resin member, comprising a step of heating and melting a composition containing an copolymer of ethylene and an olefin having 3 or more carbon atoms, a saturated hydrocarbon compound, and carbon fibers to form the resin member. The method for producing a resin member according to claim 13, wherein in the step, the composition is molded by injection molding, compression molding or transfer molding.

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