Heat-storable aromatic polycarbonate resin composition

Abstract

To provide a heat-storable aromatic polycarbonate resin composition capable of retaining the intrinsic characteristics of the aromatic polycarbonate resin to the greatest extent while preventing delamination and exhibiting both superior heat storage performance and superior impact strength.SOLUTION: The present invention relates to a heat-storable aromatic polycarbonate resin composition that comprises, per 100 pts.wt. of an aromatic polycarbonate resin (A), 1 to 30 pts.mass of a polyethylene-based heat storage material composition (B), and 1 to 15 pts.mass of an unsaturated carboxylic acid-modified styrene-based rubbery polymer (C).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a heat storage aromatic polycarbonate resin composition. [Background technology]

[0002] Aromatic polycarbonate resins have excellent mechanical, electrical, weather, water, chemical, and solvent resistance, making them suitable for a variety of applications, including electrical and electronic components, machinery components, and automotive parts. These applications include portable information terminals (PDAs) such as PCs, televisions, smartphones, and tablets, as well as audio and video equipment, lighting fixtures such as lamps, and various devices equipped with power devices such as semiconductor control devices and inverters. While heat generation in these electronic devices is increasing due to battery heat generation, increasingly highly integrated CPUs, and increasingly bright LEDs, miniaturization of the devices is a key requirement. This can lead to high temperatures inside the housing, potentially resulting in unpleasant odors, smoke, or fire. Therefore, the importance of thermal management for heat-generating devices is becoming increasingly important.

[0003] Patent Document 1 discloses a heat storage capsule in which a heat storage material that stores heat by phase transition is encapsulated in a resin capsule, and reports a technology in which adding the heat storage capsule to a heat medium enables efficient heat transport by transferring heat stored as latent heat in the heat storage material. It has also been proposed to use heat storage materials such as heat storage capsules as building materials, and studies have been conducted on using synthetic resin sheets attached to walls, or using boards containing materials with heat storage properties on the walls of houses. For example, Patent Document 2 discloses a crystalline higher α-olefin polymer obtained from a higher α-olefin having 10 or more carbon atoms as a heat storage material.

[0004] The use of the heat storage materials described in the above patent documents has had problems with processability, the appearance of the molded product, the impact strength of the molded product, etc. Furthermore, while it is expected that the heat storage materials will be mixed with thermoplastic resins to develop a variety of applications, for example, the compatibility between the heat storage materials and aromatic polycarbonate resins is insufficient, making practical use difficult. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 7-26251 [Patent Document 2] International Publication No. 2003-070790 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide a heat-storing aromatic polycarbonate resin composition that maintains the inherent properties of aromatic polycarbonate resins to the greatest extent possible, does not cause delamination, and has both excellent heat storage capacity and excellent impact strength. [Means for solving the problem]

[0007] As a result of intensive research conducted by the present inventors to solve these problems, they discovered that blending an aromatic polycarbonate resin with a polyethylene-based heat storage material composition and an unsaturated carboxylic acid-modified styrene-based rubbery polymer can maintain the inherent properties of the aromatic polycarbonate resin to the greatest extent possible, without causing delamination, and can provide both excellent heat storage properties and excellent impact strength, thereby completing the present invention.

[0008] That is, the present invention (1) is a heat storage aromatic polycarbonate resin composition containing 100 parts by weight of an aromatic polycarbonate resin (A), 1 to 30 parts by mass of a polyethylene-based heat storage material composition (B), and 1 to 15 parts by mass of an unsaturated carboxylic acid-modified styrene-based rubbery polymer (C).

[0009] The present invention (2) is the heat storage aromatic polycarbonate resin composition according to the present invention (1), wherein the polyethylene-based heat storage material composition (B) contains a polyethylene-based polymer (b1) and a polypropylene-based polymer (b2) containing at least one selected from a propylene homopolymer, a propylene-1-butene-ethylene copolymer, and an ethylene-propylene block copolymer.

[0010] The present invention (3) is the heat storage aromatic polycarbonate resin composition according to the present invention (1) or (2), wherein the unsaturated carboxylic acid-modified styrene-based rubbery polymer (C) is a maleic anhydride-grafted modified styrene-ethylene / butylene-styrene block copolymer.

[0011] The present invention (4) is the heat storage aromatic polycarbonate resin composition according to any one of the present inventions (1) to (3), further comprising 0.5 parts by mass or less of a phosphorus-based antioxidant (D) per 100 parts by mass of the aromatic polycarbonate resin (A).

[0012] The present invention (5) is the heat storage aromatic polycarbonate resin composition according to the present invention (4), wherein the phosphorus-based antioxidant (D) is a phosphite ester compound having the following phosphite ester structure: [ka]

[0013] The present invention (6) is the heat storage aromatic polycarbonate resin composition according to any one of the present inventions (1) to (5), which is used for a housing surrounding a heat generating element of an electronic component.

[0014] The present invention (7) is a housing for enclosing a heat generating element of an electronic component, which is produced by molding the heat storage aromatic polycarbonate resin composition according to the present invention (6). [Effects of the Invention]

[0015] The heat-storage aromatic polycarbonate resin composition of the present invention maintains the inherent properties of aromatic polycarbonate resins to the greatest extent possible, and exhibits both excellent heat storage properties and excellent impact strength without causing delamination. It can be suitably used as a heat-storage resin composition, and is suitable for applications such as building materials, apparel, electronic materials, logistics materials, automotive materials, and product housings for enclosing heating elements in electronic components, making it highly valuable for industrial use. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments will be described in detail. However, more detailed explanations than necessary may be omitted. For example, detailed explanations of well-known matters or redundant explanations of substantially identical configurations may be omitted. This is to avoid unnecessary redundancy in the following explanation and to facilitate understanding by those skilled in the art. Note that the inventors provide the following explanation to enable those skilled in the art to fully understand the present invention, and it is not intended to limit the subject matter described in the claims.

[0017] The aromatic polycarbonate resin composition of the present invention is characterized by containing 1 to 30 parts by mass of a polyethylene-based heat storage material composition (B) and 1 to 15 parts by mass of an unsaturated carboxylic acid-modified styrene-based rubbery polymer (C) relative to 100 parts by weight of an aromatic polycarbonate resin (A).

[0018] The aromatic polycarbonate resin (A) used in the present invention is a polymer obtained by the phosgene method in which various dihydroxydiaryl compounds are reacted with phosgene, or by the transesterification method in which a dihydroxydiaryl compound is reacted with a carbonate ester such as diphenyl carbonate, and a representative example is a polycarbonate resin produced from 2,2-bis(4-hydroxyphenyl)propane (commonly known as bisphenol A).

[0019] Dihydroxydiaryl compounds include, in addition to bisphenol A, bis(hydroxyaryl)alkanes such as bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane, bis(4-hydroxyphenyl)phenylmethane, 2,2-bis(4-hydroxyphenyl-3-methylphenyl)propane, 1,1-bis(4-hydroxy-3-tert-butylphenyl)propane, 2,2-bis(4-hydroxy-3-bromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, and 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane; dihydroxydiaryl ethers such as 4,4'-dihydroxydiphenyl ether and 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether; dihydroxydiaryl sulfides such as 4,4'-dihydroxydiphenyl sulfoxide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide; and dihydroxydiaryl sulfones such as 4,4'-dihydroxydiphenyl sulfone and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone.

[0020] These may be used alone or in combination of two or more. In addition to these, piperazine, dipiperidylhydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, etc. may also be used in combination.

[0021] Furthermore, the above dihydroxyaryl compounds may be used in combination with the following trivalent or higher phenolic compounds: Trivalent or higher phenolic compounds include phloroglucin, 4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptene, 2,4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptane, 1,3,5-tri-(4-hydroxyphenyl)-benzene, 1,1,1-tri-(4-hydroxyphenyl)-ethane, and 2,2-bis-[4,4-(4,4'-dihydroxydiphenyl)-cyclohexyl]-propane.

[0022] The viscosity average molecular weight of the aromatic polycarbonate resin (A) is not particularly limited, but from the viewpoints of moldability and strength, it is usually 10,000 to 100,000, more preferably 16,000 to 30,000, and even more preferably 19,000 to 26,000. In producing such a polycarbonate resin, a molecular weight modifier, a catalyst, etc. may be used as needed.

[0023] The form of the aromatic polycarbonate resin (A) is not particularly limited, and examples thereof include pellets, flakes, beads, etc. Among these, flakes are preferred, and porous flakes are more preferred, in that they provide uniform dispersion. The bulk density of the polycarbonate is also not particularly limited, but is preferably 0.1 to 0.9, more preferably 0.1 to 0.7. Here, bulk density refers to a value measured in accordance with the packed apparent bulk density of JIS K7370. The size of the polycarbonate is not particularly limited, but is preferably 5 mm or less.

[0024] The polyethylene-based heat storage material composition (B) used in the present invention is not particularly limited as long as it contains a polyethylene homopolymer or copolymer and has heat storage properties. Here, the term "heat storage material" refers to a latent heat storage material, which is a material that can maintain temperature during a phase change by utilizing the "latent heat" required for the phase change. Paraffin is commonly known as a latent heat storage material, but because paraffin becomes liquid during a phase change, it must be encapsulated in a plastic container or microcapsules. On the other hand, the polyethylene-based heat storage material composition (B) does not need to be encapsulated in a container because a portion of its chemical structure undergoes a phase change, allowing it to maintain a solid form during the phase change.

[0025] Examples of such heat storage materials include those containing a polyethylene polymer (b1) described in International Publication No. 2015 / 156416 and a polypropylene polymer (b2) consisting of at least one selected from a propylene homopolymer, a propylene-1-butene-ethylene copolymer, and an ethylene-propylene block copolymer. Commercially available products include the HEATORAGE series manufactured by Sumitomo Chemical Co., Ltd.

[0026] The content of the polyethylene polymer (b1) is preferably 70 to 100% by mass, and the content of the polypropylene polymer (b2) made of at least one selected from a propylene homopolymer, a propylene-1-butene-ethylene copolymer, and an ethylene-propylene block copolymer is preferably 30 to 0% by mass.

[0027] The blending amount of the polyethylene-based heat storage material composition (B) is 1 to 30 parts by mass, preferably 10 to 30 parts by mass, per 100 parts by weight of the aromatic polycarbonate resin (A). If it is less than 1 part by mass, sufficient heat storage properties are not exhibited, and if it exceeds 30 parts by mass, processability deteriorates.

[0028] The unsaturated carboxylic acid-modified styrene-based rubbery polymer (C) used in the present invention is a rubbery polymer (elastomer) obtained by graft-modifying a styrene-based rubbery polymer with an unsaturated carboxylic acid. The aromatic polycarbonate resin and the polyethylene-based heat storage material composition have extremely low compatibility, and are blended to improve, for example, the greatly reduced impact resistance.

[0029] Examples of styrene-based rubbery polymers include copolymers of styrene with diene compounds, acrylonitrile, etc., and further, those in which part of the styrene, diene compounds, or acrylonitrile has been substituted with a vinyl monomer copolymerizable with styrene, such as a styrene-based monomer such as α-methylstyrene, p-methylstyrene, or pt-butylstyrene; an ester compound of (meth)acrylic acid, such as methyl, ethyl, propyl, or n-butyl; or a maleimide-based monomer such as maleimide, N-methylmaleimide, N-cyclohexylmaleimide, or N-phenylmaleimide.

[0030] Specific examples of styrene-based rubbery polymers include styrene-butadiene copolymers, hydrogenated styrene-butadiene copolymers, styrene-butadiene-styrene copolymers, hydrogenated styrene-butadiene-styrene copolymers, styrene-ethylene / butylene-styrene copolymers, butadiene copolymers, styrene-isoprene copolymers, hydrogenated styrene-isoprene copolymers, styrene-isoprene-styrene copolymers, hydrogenated styrene-isoprene-styrene copolymers, butadiene-acrylonitrile-styrene copolymers, methyl methacrylate-butadiene-styrene copolymers, methyl methacrylate-butyl acrylate-styrene copolymers, octyl acrylate-butadiene-styrene copolymers, alkyl acrylate-butadiene-acrylonitrile-styrene copolymers, butadiene-styrene copolymers, etc. The styrene-based rubbery polymers can be used alone or in combination of two or more.

[0031] Examples of the unsaturated carboxylic acid-modified styrene-based rubbery polymer (C) include those in which a portion of the monomers such as styrene in the above-mentioned styrene-based rubbery polymer has been replaced with an unsaturated carboxylic acid monomer, and those in which an unsaturated carboxylic acid has been block copolymerized with a styrene-based rubbery polymer.

[0032] Examples of the unsaturated carboxylic acid monomer include maleic anhydride, fumaric acid, fumaric acid diesters, metal fumarate salts, ammonium fumarate salts, and fumaric acid halides, among which maleic anhydride is preferred. These unsaturated carboxylic acid monomers can be used alone or in combination of two or more.

[0033] The degree of unsaturated carboxylic acid modification in the unsaturated carboxylic acid-modified styrene-based rubbery polymer (C) (mass % of unsaturated carboxylic acid relative to 100 mass % of unmodified styrene-based rubbery polymer) is preferably 0.5 to 20 mass %, more preferably 1 to 10 mass %, and even more preferably 1 to 5 mass %.

[0034] As the unsaturated carboxylic acid-modified styrene-based rubbery polymer (C), an unsaturated carboxylic acid-modified product of styrene-ethylene / butylene-styrene copolymer (SEBS) is preferred, and maleic anhydride-modified styrene-ethylene / butylene-styrene copolymer (m-SEBS) is particularly preferred.

[0035] The unsaturated carboxylic acid-modified styrene-based rubbery polymer (C) is not limited in any way in its production method, and can be obtained by known methods, such as emulsion polymerization, bulk polymerization, suspension polymerization, solution polymerization, etc., or a combination of these methods.

[0036] In addition, commercially available products can be used as the unsaturated carboxylic acid-modified styrene-based rubbery polymer (C). Suitable examples include "TUFTECH M1913" (trade name), a maleic anhydride-grafted styrene-ethylene / butylene-styrene copolymer manufactured by Asahi Chemicals Co., Ltd., "TAIPOL SEBS-7131" (trade name), a maleic anhydride-grafted styrene-ethylene / butylene-styrene copolymer manufactured by TSRC Corporation in Taiwan, and KRATON (registered trademark) FG1901 and KRATON FG1924 manufactured by KRATON.

[0037] The blending amount of the unsaturated carboxylic acid-modified styrene-based rubbery polymer (C) is 1 to 15 parts by mass, preferably 3 to 12 parts by mass, and more preferably 8 to 12 parts by mass, per 100 parts by mass of the aromatic polycarbonate resin. If the blending amount is within this range, impact strength and heat resistance are maintained.

[0038] In the present invention, if necessary, a phosphorus-based antioxidant (D) may be further contained. Examples of the phosphorus-based antioxidant (D) include phosphite ester compounds having a phosphite ester structure represented by the following formula:

[0039] [ka]

[0040] As the phosphite ester compound having the phosphite ester structure represented by the above formula, those represented by the following formulas (1) to (5) can be suitably used.

[0041] [ka] (In the formula, R 1 represents an alkyl group having 1 to 20 carbon atoms, and a represents an integer of 0 to 3.

[0042] In formula (1), R 1 is an alkyl group having 1 to 20 carbon atoms, preferably an alkyl group having 1 to 10 carbon atoms.

[0043] Examples of the compound represented by formula (1) include triphenyl phosphite, tricresyl phosphite, tris(2,4-di-t-butylphenyl) phosphite, trisnonylphenyl phosphite, etc. Among these, tris(2,4-di-t-butylphenyl) phosphite is particularly preferred, and is commercially available, for example, as Irgafos 168 manufactured by BASF ("Irgafos" is a registered trademark of BASF Societas Europea).

[0044] [ka] (In the formula, R 2 , R 3 , R 5 and R 6 R each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group. 4 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms; X represents a single bond, a sulfur atom, or a group of the formula: -CHR 7 -(where R 7 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms. A represents an alkylene group having 1 to 8 carbon atoms or a group represented by the formula: *-COR 8 -(where R 8 represents a single bond or an alkylene group having 1 to 8 carbon atoms, and * represents a bond on the oxygen side. Either Y or Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms, and the other represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

[0045] In equation (2), R 2 , R 3 , R 5 and R 6are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group.

[0046] Examples of alkyl groups having 1 to 8 carbon atoms include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, t-butyl, t-pentyl, i-octyl, t-octyl, and 2-ethylhexyl groups. Examples of cycloalkyl groups having 5 to 8 carbon atoms include cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups. Examples of alkylcycloalkyl groups having 6 to 12 carbon atoms include 1-methylcyclopentyl, 1-methylcyclohexyl, and 1-methyl-4-i-propylcyclohexyl groups. Examples of aralkyl groups having 7 to 12 carbon atoms include benzyl, α-methylbenzyl, and α,α-dimethylbenzyl groups.

[0047] R 2 , R 3 and R 5 are each independently preferably an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcycloalkyl group having 6 to 12 carbon atoms. 2 and R 5 are each independently preferably a t-alkyl group such as a t-butyl group, a t-pentyl group, or a t-octyl group, a cyclohexyl group, or a 1-methylcyclohexyl group. 3 As the alkyl group, an alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a sec-butyl group, a t-butyl group, or a t-pentyl group is preferred, and a methyl group, a t-butyl group, or a t-pentyl group is more preferred.

[0048] R 6is preferably a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms, and more preferably a hydrogen atom, or an alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a sec-butyl group, a t-butyl group, or a t-pentyl group.

[0049] R 4 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Examples of the alkyl group having 1 to 8 carbon atoms include the above-mentioned R 2 , R 3 , R 5 and R 6 In particular, the alkyl groups exemplified in the explanation of R 4 is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably a hydrogen atom or a methyl group.

[0050] X is a single bond, a sulfur atom or a group of the formula: -CHR 7 -, where the formula is -CHR 7 -R in 7 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms. Examples of the alkyl group having 1 to 8 carbon atoms and the cycloalkyl group having 5 to 8 carbon atoms include the above-mentioned R 2 , R 3 , R 5 and R 6 Examples of X include the alkyl groups and cycloalkyl groups exemplified in the description of 1. In particular, X is preferably a single bond, a methylene group, or a methylene group substituted with a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a t-butyl group, or the like, and more preferably a single bond.

[0051] A is an alkylene group having 1 to 8 carbon atoms or a group represented by the formula: *-COR 8 - represents a group represented by the formula: *-COR. Examples of the alkylene group having 1 to 8 carbon atoms include a methylene group, an ethylene group, a propylene group, a butylene group, a pentamethylene group, a hexamethylene group, an octamethylene group, and a 2,2-dimethyl-1,3-propylene group, and the like, with a propylene group being preferred.8 -R in 8 represents a single bond or an alkylene group having 1 to 8 carbon atoms. 8 Examples of the alkylene group having 1 to 8 carbon atoms represented by R include the alkylene groups exemplified in the description of A. 8 is preferably a single bond or an ethylene group. 8 The * in - is the bond on the oxygen side, indicating that the carbonyl group is bonded to the oxygen atom of the phosphite group.

[0052] Either Y or Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms, and the other represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Examples of the alkoxy group having 1 to 8 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, a t-butoxy group, and a pentyloxy group. Examples of the aralkyloxy group having 7 to 12 carbon atoms include a benzyloxy group, an α-methylbenzyloxy group, and an α,α-dimethylbenzyloxy group. Examples of the alkyl group having 1 to 8 carbon atoms include the above-mentioned R 2 , R 3 , R 5 and R 6 Examples of the alkyl groups include those exemplified in the explanation of 1.

[0053] Examples of the compound represented by formula (2) include 2,4,8,10-tetra-t-butyl-6-[3-(3-methyl-4-hydroxy-5-t-butylphenyl)propoxy]dibenzo[d,f][1,3,2]dioxaphosphepine, 6-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propoxy]-2,4,8,10-tetra-t-butyldibenzo[d,f][1,3,2]dioxaphosphepine, 6 -[3-(3,5-di-t-butyl-4-hydroxyphenyl)propoxy]-4,8-di-t-butyl-2,10-dimethyl-12H-dibenzo[d,g][1,3,2]dioxaphosphocin, 6-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy]-4,8-di-t-butyl-2,10-dimethyl-12H-dibenzo[d,g][1,3,2]dioxaphosphocin, and the like. Among these, when the polycarbonate resin composition is used in a field where optical properties are particularly required, 2,4,8,10-tetra-t-butyl-6-[3-(3-methyl-4-hydroxy-5-t-butylphenyl)propoxy]dibenzo[d,f][1,3,2]dioxaphosphepine is suitable, and is commercially available, for example, as Sumilizer GP ("Sumilizer" is a registered trademark) manufactured by Sumitomo Chemical Co., Ltd.

[0054] [ka] (In the formula, R 9 and R 10 each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group which may be substituted with an alkyl group, and b and c each independently represent an integer of 0 to 3.

[0055] Examples of the compound represented by formula (3) include bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, phenylbisphenol A pentaerythritol diphosphite, etc. Bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite is commercially available as ADK STAB PEP-36 manufactured by ADEKA CORPORATION ("ADK STAB" is a registered trademark).

[0056] [ka] (In the formula, R 11 ~R 18 R each independently represents an alkyl group or alkenyl group having 1 to 3 carbon atoms. 11 and R 12 , R 13 and R 14 , R 15 and R 16 , R 17 and R 18 may be bonded to each other to form a ring. 19 ~R 22 each independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. d to g each independently represents an integer of 0 to 5. X 1 ~X 4 X each independently represents a single bond or a carbon atom. 1 ~X 4 is a single bond, R 11 ~R 22 The functional group connected to the single bond is excluded from formula (4).

[0057] A specific example of the compound represented by formula (4) is bis(2,4-dicumylphenyl)pentaerythritol diphosphite, which is commercially available from Dover Chemical under the trade name "Doverphos (registered trademark) S-9228" and from ADEKA under the trade name "ADEKA STAB PEP-45" (bis(2,4-dicumylphenyl)pentaerythritol diphosphite).

[0058] Furthermore, instead of or in addition to any of the compounds represented by the above formulas (1) to (4), a compound represented by the following formula (5) may be used.

[0059] [ka] (In the formula, R 23 ~R26 represents an alkyl group having 1 to 20 carbon atoms or an aryl group which may be substituted with an alkyl group.

[0060] Specific examples of the compound represented by formula (5) include [1,1'-biphenyl]-4,4-diylbis[bis(2,4-di-t-butylphenoxy)phosphine], etc. For example, Irgafos P-EPQ (trade name) manufactured by BASF and Sandstab P-EPQ (trade name) manufactured by Clariant Japan Co., Ltd. are commercially available.

[0061] The amount of the phosphite ester compound (D) is preferably 0.5 parts by mass or less per 100 parts by mass of the aromatic polycarbonate resin (A). If the amount of the phosphite ester compound exceeds 0.5 parts by mass, the impact strength may decrease.

[0062] The polycarbonate resin composition of the present invention may contain additives other than the above-mentioned components, such as a heat stabilizer, a colorant, a release agent, a softener, an antistatic agent, an impact modifier, an ultraviolet absorber, a pigment, a filler, and a flow improver, as long as the effects of the composition are not impaired.

[0063] In the polycarbonate resin composition of the present invention, the endothermic peak temperature and exothermic peak temperature are preferably 20 to 60°C, and the endothermic amount and exothermic amount are preferably 5 J / g or more. The notched Charpy impact strength according to ISO179-2 is 30 kJ / m 2 is preferred.

[0064] The molded article of the present invention is characterized by containing the aromatic polycarbonate resin composition of the present invention. The molded article of the present invention can be produced by extrusion molding or injection molding using the polycarbonate resin composition of the present invention. For extrusion molding, molding such as sheet or profile extrusion using an extruder is used, and for injection molding, a mold capable of molding the molded article and an injection molding machine of 100 to 200T class are used. The molding temperature is preferably 240 to 280°C.

[0065] The heat-storage aromatic polycarbonate resin composition of the present invention can be suitably used as a heat-storage resin composition that combines excellent heat storage properties and excellent impact strength without causing delamination while maintaining the original properties of aromatic polycarbonate resin to the greatest extent possible, and can be suitably used as a building material, apparel, electronic material, logistics material, automotive material, product housing for enclosing heating elements of electronic components, etc.

[0066] The housing of the present invention is characterized in that it is a housing for enclosing a heat generating element of an electronic component, which is produced by molding the heat storage aromatic polycarbonate resin composition of the present invention. [Example]

[0067] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" and "%" are based on mass.

[0068] The following raw materials were used: (A) Polycarbonate resin Sumika Polycarbonate Co., Ltd. SD Polycarbonate 200-20 (B) Polyethylene-based heat storage material composition A composition comprising a polyethylene polymer (b1) and a polypropylene polymer (b2) consisting of at least one selected from a propylene homopolymer, a propylene-1-butene-ethylene copolymer, and an ethylene-propylene block copolymer. HEATRAGE SC35-A80 manufactured by Sumitomo Chemical Co., Ltd.: Contains 70 to 100% by mass of polyethylene polymer, and 0 to 30% of polypropylene polymer consisting of propylene homopolymer, EPB random copolymer, and EP block copolymer. (C) Unsaturated carboxylic acid modified styrene rubber polymer m-SEBS (maleic anhydride modified SEBS): Asahi Kasei Corporation Tuftec M19 13 (D) Phosphorus-based antioxidants (D) (phosphite ester compounds) Tris(2,4-di-t-butylphenyl)phosphite, represented by the following formula:

[0069] [ka] BASF Irgafos 168 (trade name)

[0070] Examples 1 to 4 and Comparative Examples 1 to 2 The components were dry- and wet-mixed in a tumbler in the blending ratios shown in Table 1, and then melt-kneaded at a kneading temperature of 260°C using a twin-screw extruder (TEX30α, manufactured by The Japan Steel Works, Ltd.) to obtain pellets of the heat storage aromatic polycarbonate resin composition of each Example and Comparative Example. The obtained pellets were used to perform the following various evaluations. The evaluation results are shown in Table 1.

[0071] <Heat storage> Using a differential scanning calorimeter (NETZSCH DSC3500 Sirius), an aluminum pan containing approximately 6 mg of the resulting pellets was subjected to the following temperature program twice under a nitrogen atmosphere. The endothermic amount and endothermic peak temperature were calculated from the peak obtained in the second run of step (2). Tests in which a peak was obtained were rated as passing, and those in which a peak was not obtained were rated as failing. Furthermore, the heat release amount and heat release peak temperature were calculated from the peak obtained in the second run of step (4). Tests in which a peak was obtained were rated as passing, and those in which a peak was not obtained were rated as failing.

[0072] Temperature Program (1) Keep at -50°C for 15 minutes (2) Heat from -50°C to 90°C at a rate of 5°C / min (3) Keep at 90°C for 15 minutes (4) The temperature is decreased from 90°C to -50°C at a rate of 5°C / min.

[0073] <Impact strength> Pellets of the resin compositions prepared in each example and comparative example were dried at 120°C for at least 4 hours, and then test specimens were prepared in accordance with the ISO test method using an injection molding machine (FANUC Corporation, ROBOSHOT S2000i100B) at a molding temperature of 280°C and a mold temperature of 80°C. The notched Charpy impact strength of the obtained test specimens was measured in accordance with ISO179-2, and the test specimens were found to have a strength of 30 kJ / m. 2 Less than 30kJ / m is unacceptable 2 The above is considered a pass.

[0074] <Cross-cut peel test> Pellets of the resin compositions prepared in each example and comparative example were dried at 120°C for 4 hours or more, and then flat test specimens (80 mm long, 50 mm wide, 2 mm thick) were prepared using an injection molding machine (ROBOSHOT S2000i100B, manufactured by FANUC CORPORATION) at a molding temperature of 260°C. A cross-cut test of 100 squares was carried out using these flat test specimens directly below the gate, and a score of 5 or less of the squares that peeled off was judged as pass (◯), and a score of more than 5 was judged as fail (×).

[0075] <Thermal stability> The pellets of the resin compositions prepared in Examples 2 and 4 were dried at 120°C for 4 hours or more, and then flat test specimens (length 80 mm, width 50 mm, thickness 2 mm) were prepared using an injection molding machine (ROBOSHOT S2000i100B, manufactured by Fanuc Corporation) at a molding temperature of 260°C, and the YI was measured using a spectrophotometer (CMS-35SP, manufactured by Murakami Color Research Institute).

[0076] [Table 1]

[0077] From the evaluation results in Table 1, when specific amounts of the polyethylene-based heat storage material composition (B) and the unsaturated carboxylic acid-modified styrene-based rubbery polymer (C) were blended with the aromatic polycarbonate resin (A), molded articles having both excellent heat storage properties and excellent impact strength were obtained as shown in Examples 1 to 4. On the other hand, when only the heat storage material composition was blended, compatibility was poor as shown in Comparative Example 2, and only molded articles with poor adhesion and impact resistance were obtained. [Industrial Applicability]

[0078] The heat-storage aromatic polycarbonate resin composition of the present invention can be suitably used as a heat-storage resin composition that combines excellent heat storage capacity and excellent impact strength without causing delamination while maintaining the inherent properties of aromatic polycarbonate resin to the greatest extent possible, and has high industrial utility value in applications such as building materials, apparel, electronic materials, logistics materials, and automotive materials.

Claims

1. A heat storage aromatic polycarbonate resin composition containing 100 parts by weight of an aromatic polycarbonate resin (A), 1 to 30 parts by mass of a polyethylene-based heat storage material composition (B), and 1 to 15 parts by mass of an unsaturated carboxylic acid-modified styrene-based rubbery polymer (C).

2. The polyethylene-based heat storage material composition (B) contains a polyethylene-based polymer (b1) and a polypropylene-based polymer (b2) containing at least one selected from a propylene homopolymer, a propylene-1-butene-ethylene copolymer, and an ethylene-propylene block copolymer. The heat-storing aromatic polycarbonate resin composition according to claim 1.

3. 3. The heat-storing aromatic polycarbonate resin composition according to claim 1, wherein the unsaturated carboxylic acid-modified styrene-based rubbery polymer (C) is a maleic anhydride-grafted styrene-ethylene / butylene-styrene block copolymer.

4. 3. The heat storage aromatic polycarbonate resin composition according to claim 1, further comprising 0.5 parts by mass or less of a phosphorus-based antioxidant (D) per 100 parts by mass of the aromatic polycarbonate resin (A).

5. 5. The heat storage aromatic polycarbonate resin composition according to claim 4, wherein the phosphorus-based antioxidant (D) is a phosphite ester compound having the following phosphite ester structure: 【Chemistry 1】

6. 3. The heat storage aromatic polycarbonate resin composition according to claim 1, which is used for a housing that surrounds a heat generating element of an electronic component.

7. A housing for enclosing a heat generating element of an electronic component, which is produced by molding the heat storage aromatic polycarbonate resin composition according to claim 6.

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