JP2011184681A - Resin composition and method of producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition having both thermal conductivity and insulation at high levels and hardly expressing the anisotropy of thermal conductivity even during processing under shearing such as injection molding, and to provide a method of producing the same. <P>SOLUTION: The resin composition contains (A) a conductive nano filler, (B) two or more resin, and (C) a compound having a functional group. The resin composition is provided with a dispersion phase formed of a resin (B<SB>aff</SB>) having the highest affinity for the conductive nano filler (A) among the two or more resin (B) and a continuous phase formed of the remaining one or more resin (B1), wherein in the dispersion phase, the conductive nano filler (A) is present and when the content of the dipsersion phase in the whole resin composition is X (unit: content%) and the content of the conductive nano filler (A<SB>dsp</SB>) contained in the dispersion phase, with respect to the whole conductive nano filler (A) is Y (unit: content%), Y is 20 content% or more and Y/X is 1.2 or more. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a resin composition containing a conductive nanofiller and a method for producing the same.

  Conductive nanofillers typified by carbon nanofillers are excellent in thermal conductivity, electrical conductivity, mechanical properties, etc., so they are added to resins to impart or improve these properties. It is being considered. Among the resin properties that are improved by the addition of such conductive nanofillers, it was possible to improve the electrical conductivity relatively easily, but it was not easy to significantly improve the thermal conductivity. .

  Therefore, as a resin composition with improved thermal conductivity, Japanese Patent Application Laid-Open No. 2005-54094 (Patent Document 1) discloses thermal conduction in which carbon such as fibrous carbon is dispersed in two or more kinds of resin mixtures. Resin materials have been proposed. In this resin material, carbon is selectively dispersed only in one kind of resin phase to form a heat conduction path made of carbon, and thus the heat conductivity is enhanced. It also acts as a path and improves electrical conductivity. For this reason, this resin material cannot be applied to applications that require thermal conductivity (heat dissipation) and insulation.

  Japanese Patent Application Laid-Open No. 2005-150362 (Patent Document 2) discloses a high heat conductive sheet in which a heat conductive filler such as carbon nanotube is dispersed in a general-purpose resin, and further the electric conductivity of the sheet. It is also disclosed to disperse an electrically insulating material such as alumina in order to suppress electrical shorts and prevent electrical shorts. However, even when an electrically insulating material such as alumina is dispersed in a high thermal conductive sheet in which carbon nanotubes are dispersed, a high degree of insulation is not achieved, and the anisotropy of the thermal conductivity of the high thermal conductive sheet is large. Further, when a large amount of these electrically insulating materials having a large specific gravity is added in order to improve the insulating properties, the specific gravity of the sheet tends to increase or the molding processability and toughness tend to decrease. In applications such as various parts of moving media and parts for electric and electronic equipment, especially for various resin parts for automobiles, weight reduction and higher functionality of materials are required from the viewpoint of reducing carbon dioxide emissions and saving energy. Therefore, there has been a demand for a resin material that has both thermal conductivity and insulation while suppressing an increase in specific gravity and maintaining good moldability.

JP 2005-54094 A JP 2005-150362 A

  The present invention has been made in view of the above-mentioned problems of the prior art, has both high thermal conductivity and insulating properties, and also has different thermal conductivity even in processing under shear such as injection molding. It is an object of the present invention to provide a resin composition that is less likely to exhibit a directivity and a method for producing the same.

  As a result of intensive studies to achieve the above object, the inventors have added a compound having a functional group to a resin composition containing a conductive nanofiller and two or more kinds of resins. 1A to FIG. 1C (the components of each phase in the drawing depict the main components, and the components in each phase of the resin composition of the present invention are not limited thereto). It is found that a phase structure composed of a dispersed phase containing a conductive nanofiller and a continuous phase is formed, and further, such a phase structure makes it possible to prevent electrical short-circuiting, and the resin composition has thermal conductivity and insulation. In addition, the present inventors have found that the anisotropy of thermal conductivity is difficult to develop even in processing under shear, and have completed the present invention.

That is, the resin composition of the present invention is
It is a resin composition containing a conductive nanofiller (A), two or more kinds of resins (B), and a compound (C) having a functional group,
The resin composition includes a dispersed phase formed of a resin (B _aff ) having the highest affinity with the conductive nanofiller (A) of the two or more types of resins (B), and the remaining one or more types. A continuous phase formed of the resin (B1)
In the dispersed phase, the conductive nanofiller (A) exists,
The ratio of the dispersed phase to the entire resin composition is X (unit: volume%), and the ratio of the conductive nanofiller (A _dsp ) contained in the dispersed phase to the total conductive nanofiller (A) is Y ( Unit: volume%), Y is 20 volume% or more, and Y / X is 1.2 or more.

In such a resin composition, the content of the resin (B _aff ) having the highest affinity with the conductive nanofiller (A) is preferably 70% by volume or less based on the entire resin composition. In addition, the resin composition of the present invention preferably has a thermal conductivity of 0.3 W / mK or more and a volume resistivity of 10 ¹³ Ω · cm or more.

Moreover, the method for producing the resin composition of the present invention comprises:
A method for producing a resin composition comprising a conductive nanofiller (A), two or more kinds of resins (B), and a compound (C) having a functional group,
At least part of the conductive nanofiller (A) and at least part of the resin (B _aff ) having the highest affinity with the conductive nanofiller (A) of the two or more kinds of resins (B); To prepare a mixture of the conductive nanofiller (A) and the resin (B _aff ),
The method is characterized by mixing the mixture, one or more remaining resins (B1) of the two or more resins (B), and a compound (C) having a functional group.

  In the resin composition of the present invention and the production method thereof, the conductive nanofiller (A) is preferably a carbon-based nanofiller. The functional group of the compound (C) includes alkoxysilyl group, silanol group, epoxy group, isocyanate group, amino group, hydroxyl group, mercapto group, ureido group, carboxyl group, carboxylic anhydride group, oxetane group and oxazoline. At least one group selected from the group consisting of groups is preferred.

In addition, electroconductivity as shown to FIG. 1A-FIG. 1C by adding a functional group containing compound (C) to the resin composition containing electroconductive nanofiller (A) and 2 or more types of resin (B). Although the reason why the phase structure composed of the dispersed phase 3 containing the nanofiller (A) 1 and the continuous phase 4 is formed is not necessarily clear, the present inventors infer as follows. That is, since the functional group-containing compound (C) has a high affinity and / or reactivity with the resin forming the dispersed phase 3 or the continuous phase 4, it tends to exist at the interface between the dispersed phase 3 and the continuous phase 4, It is presumed that it preferably acts as a shell of the dispersed phase 3 by reacting with the resin forming the dispersed phase 3 and / or the continuous phase 4 or by reacting the functional group-containing compound (C) with each other. The At this time, when the dispersed phase 3 is formed of a resin (B _aff ) having high affinity with the conductive nano filler (A) among the two or more kinds of resins (B), the conductive nano filler (A ) Is likely to be surrounded by the resin (B _aff ) having a high affinity, so that it is likely to be localized in the dispersed phase 3 and more easily confined in the dispersed phase 3 by the functional group-containing compound (C) 2 and / or its reaction product. It is assumed that

In the present invention, “resin (B _aff ) having high affinity with the conductive nanofiller (A)” has the highest affinity with the conductive nanofiller (A) among the two or more types of resins (B). High resin. With the resin (B _aff ), for example, two or more kinds of resins are mixed in the same volume (unit: volume%), and these resins are melted or dissolved using a solvent as necessary, and then conductive. When the nanofiller (A) is mixed, it refers to a resin containing the largest amount (unit: volume%) of the conductive nanofiller (A). Such a resin (B _aff ) is not particularly limited as long as it has the highest affinity with the conductive nanofiller (A) among the two or more kinds of resins (B). Among the resins (B) of at least species, the interface energy between the conductive nanofiller (A) is smaller, the flexibility is higher, the electron withdrawing function is larger, the viscosity is lower, π A resin having at least one of the characteristics such as -π interaction and when the conductive nanofiller (A) has a functional group such as a carboxyl group has an interaction such as a hydrogen bond is preferable. Of these, a resin having two or more characteristics is more preferable.

The reason why the resin composition of the present invention has a high level of thermal conductivity and insulation by forming a phase structure as shown in FIGS. 1A to 1C is not necessarily clear. They guess as follows. That is, in the resin composition of the present invention, since the dispersed phase 3 is easily surrounded by the functional group-containing compound (C) 2, the conductive nanofiller (A _dsp ) 1 in the dispersed phase 3 is contained in other dispersed phases or It is difficult to contact the conductive nanofiller (A) in the continuous phase 4, and it is difficult to form an electric conduction path. Further, it is presumed that the functional group-containing compound (C) 2 also plays a role of blocking electrical conduction at the interface between the dispersed phase 3 and the continuous phase 4. Therefore, as a result of these, it is presumed that the resin composition of the present invention exhibits high insulation. In addition, contact between the conductive nanofillers (A _dsp ) 1 in the dispersed phase 3 reduces the area of the interface between the conductive nanofiller (A) and the resin, which is one of the factors that cause a decrease in thermal conductivity. It is presumed that phonon scattering at the interface between the conductive nanofiller (A) and the resin can be reduced. Furthermore, since the said functional group containing compound (C) 2 also plays the role which reduces the thermal resistance of an interface, it is guessed that the heat conductivity of a resin composition improves. On the other hand, in the conventional resin composition, as shown in FIG. 2, the conductive nanofiller (A) 1 is dispersed in the resin 4, and the heat at the interface between the conductive nanofiller (A) and the resin 4 is dispersed. Since the resistance is relatively high, the thermal conductivity is not sufficiently improved, and further, an electrical conduction path is formed by contact between the conductive nanofillers (A) 1 and the insulating property is lowered.

  Further, although the reason why the resin composition of the present invention is less likely to exhibit thermal conductivity anisotropy even in processing under shear is not necessarily clear, the present inventors speculate as follows. . That is, in the resin composition of the present invention, the conductive nanofiller (A) is unevenly distributed (localized) in the dispersed phase 3, and further, a functional group-containing compound is present at the interface between the dispersed phase 3 and the continuous phase 4. Since (C) 2 exists, the orientation of the conductive nanofiller (A) by processing under shear such as injection molding can be reduced, and the thermal conductivity by the orientation of the conductive nanofiller (A). It is presumed that the anisotropy of various characteristics such as can be reduced.

  According to the present invention, it is possible to obtain a resin composition that has both high thermal conductivity and insulating properties and that hardly exhibits anisotropy in thermal conductivity even during processing under shear.

It is a schematic diagram which shows one embodiment of the resin composition of this invention containing an electroconductive nanofiller. It is a schematic diagram which shows the other embodiment of the resin composition of this invention containing an electroconductive nanofiller. It is a schematic diagram which shows the other embodiment of the resin composition of this invention containing an electroconductive nanofiller. It is a schematic diagram which shows the state of the conventional resin composition containing an electroconductive nanofiller.

  Hereinafter, the present invention will be described in detail with reference to preferred embodiments thereof.

First, the resin composition of the present invention will be described. The resin composition of the present invention contains a conductive nanofiller (A), two or more kinds of resins (B), and a compound (C) having a functional group. In this resin composition, a dispersed phase is formed by the resin (B _aff ) having the highest affinity with the conductive nanofiller (A) of the two or more types of resins (B), and the remaining one or more types. A continuous phase is formed of the resin (B1). The conductive nanofiller (A) is present in the dispersed phase.

  First, the conductive nanofiller (A) used in the present invention, two or more kinds of resins (B), and a compound (C) having a functional group will be described.

(A) Conductive nanofiller The conductive nanofiller (A) used in the present invention is not particularly limited. For example, it is coated with a carbon-based nanofiller, a metal-based nanofiller, and a metal or a conductive polymer. Nano fillers are preferred. These conductive nanofillers may be used alone or in combination of two or more. Among such conductive nanofillers, carbon-based nanofillers and metal-based nanofillers are preferable and carbon-based nanofillers are more preferable from the viewpoint of improving thermal conductivity and mechanical strength.

  The carbon-based nanofiller is not particularly limited, for example, carbon nanofiber, carbon nanohorn, carbon nanocone, carbon nanotube, carbon nanocoil, carbon microcoil, carbon nanowall, carbon nanochaplet, fullerene, carbon black, Examples include graphite, graphene, carbon nanoflakes, and derivatives thereof. These carbon-based nanofillers may be used alone or in combination of two or more. Among such carbon-based nanofillers, from the viewpoint of improving thermal conductivity and mechanical strength, carbon nanofibers, carbon nanohorns, carbon nanocones, carbon nanotubes, carbon microcoils, carbon nanocoils, carbon nanowalls, carbon nanos Anisotropic carbon-based nanofillers such as chapters, graphite and graphene are more preferable, and from the viewpoint of improving thermal conductivity, carbon nanofibers, carbon nanohorns, carbon nanocones, carbon nanotubes, carbon nanocoils, carbon nanowalls and carbon Nanochaplets are more preferred, carbon nanofibers and carbon nanotubes are particularly preferred, and carbon nanotubes are most preferred.

  The shape of such a carbon-based nanofiller may be a single trunk or a dendritic shape in which a large number of carbon-based nanofillers grow outward like branches. From the viewpoint of improvement in strength and the like, a single trunk is preferable. The carbon-based nanofiller may contain atoms, molecules, etc. other than carbon, and may contain a metal or other nanostructure as necessary.

In the present invention, among the peaks of the Raman spectrum obtained by measuring the carbon-based nanofiller with a Raman spectrophotometer, the G band observed in the vicinity of about 1585 cm ⁻¹ due to the displacement vibration of the carbon atom in the graphene structure. The ratio (G / D) of the D band observed in the vicinity of about 1350 cm ⁻¹ where there is a defect such as a dangling bond in the graphene structure is not particularly limited. In applications requiring conductivity, 0.1 or more is preferable, 1.0 or more is more preferable, 3.0 or more is more preferable, 5.0 or more is particularly preferable, and 10.0 or more is most preferable. When G / D is less than the lower limit, thermal conductivity tends not to be sufficiently improved.

  The aspect ratio of the anisotropic carbon-based nanofiller is not particularly limited, but when mixed with a resin, the addition of a small amount improves the mechanical strength and thermal conductivity such as tensile strength and impact strength of the resin composition. In view of the above, it is preferably 5 or more, more preferably 10 or more, still more preferably 20 or more, particularly preferably 40 or more, and most preferably 80 or more.

  In addition, when carbon nanotubes and / or carbon nanofibers are used as the conductive nanofiller (A), either single-layer or multi-layer (two or more layers) can be used. Can be used together.

  For such carbon-based nanofillers, a conventionally known production method such as a chemical vapor deposition method (CVD method) such as a laser ablation method, an arc synthesis method, a HiPco process, or a melt spinning method should be appropriately selected according to the application. However, it is not limited to those manufactured by these methods.

Examples of the metal-based nanofiller used in the present invention include metal fillers and fillers of metal compounds such as metal oxides and metal hydroxides. Although there is no restriction | limiting in particular as a metal which comprises such a metal type nano filler, For example, silver, copper, gold | metal | money, brass, aluminum, iron, platinum, tin, magnesium, molybdenum, rhodium, zinc, palladium, tungsten, chromium Cobalt, nickel, titanium, metallic silicon, and alloys thereof are preferable. Among these metals, from the viewpoint of improving moldability, a low melting point metal (for example, Sn), a low melting point metal compound (for example, SnO ₂ ), a tin-based alloy (for example, Sn / Ag, Sn / Cu, Low melting point alloys such as Sn / Zn, Sn / Bi, Pb / Sn, Pb / Sn / Bi, Pb / Sn / Ag) and Pb / Ag are preferable. From the viewpoint of improving thermal conductivity, silver, copper, gold, brass, aluminum, iron, platinum, tin, and alloys and oxides thereof are preferable. Furthermore, in addition to thermal conductivity, such a metal can impart a function specific to each metal (for example, antibacterial action in the case of silver) to the resin composition.

  The shape of such a metal-based nanofiller is not particularly limited, and examples thereof include granular, flat plate, rod, fiber, tube, etc. Among them, from the viewpoint of improving thermal conductivity, flat plate, An anisotropic shape such as a rod shape, a fiber shape, and a tube shape is preferable.

  In addition, the nanofiller coated with a metal or a conductive polymer used in the present invention is not particularly limited, for example, glass beads coated with a metal such as silver, copper, gold, polyaniline, polypyrrole, polyacetylene, Examples thereof include glass beads coated with a conductive polymer such as poly (paraphenylene), polythiophene, or polyphenylene vinylene.

  In the present invention, the conductive nanofiller (A) includes a carboxyl group, a nitro group, an amino group, an alkyl group, an organic silyl group in the structure of the conductive nanofiller such as the carbon nanofiller or the metal nanofiller. Substituents such as groups, polymers such as poly (meth) acrylic acid esters, those in which the conductive polymers are introduced by chemical bonding, and those in which the conductive nanofillers are coated with other conductive materials Can be used.

  The average diameter of the conductive nanofiller (A) used in the present invention is not particularly limited, but is preferably 1000 nm or less, more preferably 500 nm or less, further preferably 300 nm or less, particularly preferably 200 nm or less, and most preferably 100 nm or less. preferable. When the average diameter of the conductive nanofiller (A) exceeds the upper limit, even if the conductive nanofiller (A) is added to the resin, the addition of a small amount does not sufficiently improve the thermal conductivity, the bending elastic modulus, etc. The mechanical strength tends to be insufficient. In addition, although there is no restriction | limiting in particular as a lower limit of the average diameter of electroconductive nanofiller (A), 0.4 nm or more is preferable and 0.5 nm or more is more preferable.

  In the resin composition of the present invention, the lower limit of the content of the conductive nanofiller (A) is not particularly limited, but is preferably 0.1% by volume or more, and 0.3% by volume or more with respect to the entire resin composition. Is more preferably 0.5% by volume or more, particularly preferably 0.7% by volume or more, and most preferably 1.0% by volume or more. When the content of the conductive nanofiller (A) is less than the lower limit, the thermal conductivity and mechanical strength tend to decrease. The upper limit of the content of the conductive nanofiller (A) is not particularly limited as long as the insulating property can be maintained, but is preferably 50% by volume or less, more preferably 40% by volume or less, based on the entire resin composition, It is more preferably 30% by volume or less, particularly preferably 20% by volume or less, and most preferably 10% by volume or less. If the content of the conductive nanofiller (A) exceeds the upper limit, the moldability of the resulting resin composition tends to be lowered.

  In the resin composition of the present invention, such a conductive nanofiller (A) is usually present localized in the dispersed phase, but a part thereof may be present in the continuous phase.

(B) Resin In the present invention, two or more (preferably two) resins are used. Examples of such resin (B) include epoxy resin, phenol resin, melamine resin, thermosetting imide resin, thermosetting polyamideimide, thermosetting silicone resin, urea resin (urea resin), and unsaturated polyester resin. , Benzoguanamine resin, alkyd resin, cyanate resin, urethane resin, and diallyl phthalate resin; polystyrene, AS (acrylonitrile-styrene) resin, methyl methacrylate-acrylonitrile-styrene resin, poly (meth) acrylate methyl , Acrylic resins such as poly (meth) ethyl acrylate, poly (meth) propyl propyl, poly (meth) acrylate butyl, poly (meth) acrylic acid, and copolymers thereof, polyacrylonitrile, acrylonitrile-acrylic Methyl acid Fatty and acrylonitrile-butadiene resins such as vinyl cyanide resins, imide ring-containing vinyl polymers, polyolefin resins, acid anhydride-modified acrylic elastomers, epoxy-modified acrylic elastomers, silicone resins, polycarbonates, cyclic polyolefins, polyamides, polyethylenes Polyester resins such as terephthalate, polybutylene terephthalate, and poly 1,4-cyclohexanedimethyl terephthalate, polyarylate, liquid crystalline polyester, polyarylene ether, polyarylene sulfide such as polyphenylene sulfide, polysulfone, polyethersulfone, polyoxymethylene, poly Tetrafluoroethylene, fluorinated ethylene propylene, polychlorotrifluoroethylene, polyphenylene Fluorine resin represented by vinylidene fluoride and polyvinyl fluoride, polylactic acid, polyvinyl chloride, thermoplastic polyimide, thermoplastic polyamideimide, polyetherimide, polyetheretherketone, polyetherketoneketone, polyetheramide, polycyclic aroma And thermoplastic resins such as group group-containing polymers.

In the resin composition of the present invention, among the two or more kinds of resins (B), the resin (B _aff ) (hereinafter referred to as “high affinity” having the highest affinity with the conductive nanofiller (A). A part or all of the resin (B _aff ) ”forms a dispersed phase, and part or all of the remaining one or more types of resins (B1) (hereinafter referred to as“ other resins (B1) ”). As a result, a continuous phase is formed. Such a resin composition having a dispersed phase and a continuous phase has high insulating properties, and further, anisotropy of thermal conductivity is reduced even in processing under shear. In the present invention, the combination of the high affinity resin (B _aff ) and the other resin (B 1) is determined by the affinity between the two or more types of resins (B) to be used and the conductive nanofiller (A). Is.

Of the resins exemplified as the two or more kinds of resins (B), the resins suitably used as the high affinity resin (B _aff ) include polyolefin resins, polyarylene sulfides, polyester resins, and nitrogen atoms. Examples thereof include resins and polycyclic aromatic group-containing polymers. Among them, from the viewpoint of high affinity with the conductive nanofiller (A), polyolefin resins, polyarylene sulfides, polyamides, imide ring-containing vinyl systems Polymers, polyimides, polyetherimides, polyamideimides, and polycyclic aromatic group-containing polymers are preferable, polyolefin resins, polyarylene sulfides, polyamides, and imide ring-containing vinyl polymers are more preferable. From the viewpoint of improving heat resistance, polyarylene sulfide, poly Bromide and imide ring-containing vinyl polymer is particularly preferred.

  The polyolefin resin used in the present invention may be either linear or branched. The polyolefin resin is not particularly limited, and examples thereof include homopolymers and copolymers of olefin monomers. Examples of the olefin monomers include ethylene, propylene, 1-butene, cis-2-butene, trans-2-butene, isobutene, 1-pentene, 2-pentene, 2-methyl-1-butene, and 3-methyl-1. Monoolefin monomers such as -butene, 2,3-dimethyl-2-butene, 1-butene, 1-hexene, 1-octene, 1-nonene, 1-decene; 1,2-propadiene, methylallene, butadiene, isoprene 2,3-dimethylbutadiene, 1,3-pentadiene, 1,4-pentadiene, dicyclopentadiene, chloroprene, 1,5-hexadiene, 1,4-hexadiene, 1,4-cyclohexadiene, 5-ethylidene-2 -Diene monomers such as norbornene and halides thereof. These olefinic monomers may be used alone or in combination of two or more.

  Specific examples of such olefin monomer copolymers include ethylene-propylene copolymers, ethylene-1-butene copolymers, ethylene-4-methyl-1-pentene copolymers, and ethylene-1-hexene. Copolymer, ethylene-propylene-dicyclopentadiene copolymer, ethylene-propylene-5-vinyl-2-norbornene copolymer, ethylene-propylene-1,4-hexadiene copolymer, ethylene-propylene-1,4 -Cyclohexadiene copolymer, polystyrene-poly (ethylene / propylene) block copolymer (SEP), polystyrene-poly (ethylene / propylene) -polystyrene block copolymer (SEPS), polystyrene-poly (ethylene / butylene) polystyrene Block copolymer (SEBS), polystyrene Ethylene-based copolymers such as poly (ethylene-ethylene / propylene) -polystyrene block copolymer (SEEPS) and ethylene-1-octene copolymer; propylene-1-butene-4-methyl-1-pentene copolymer And propylene copolymers such as propylene-1-butene copolymer; styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), acrylonitrile-butadiene-styrene (ABS) Resin, (meth) acrylic acid methyl-acrylonitrile-butadiene-styrene (MABS) resin, 1-hexene-4-methyl-1-pentene copolymer, 4-methyl-1-pentene-1-octene copolymer, etc. Can be mentioned. When a polypropylene resin is used as the polyolefin resin, any polypropylene resin such as isotactic, atactic and syndiotactic can be used as the polypropylene resin.

  Of such polyolefin resins, polyethylene resins (ethylene homopolymers and copolymers) are preferred from the viewpoint of high affinity with the conductive nanofiller (A), and ethylene homopolymers and / or Or an ethylene-1-butene copolymer is more preferable. Examples of the ethylene homopolymer include linear low density polyethylene (LLDPE), low density polyethylene (LDPE), high density polyethylene (HDPE), very low density polyethylene (VLDPE), or Ultra Low Density Polyethylene. (ULDPE)), ultrahigh molecular weight polyethylene (UHMW-PE, generally having a molecular weight of 1.5 million or more), and the like, and HDPE is particularly preferable from the viewpoint of high thermal conductivity.

In addition, an ethylene-based copolymer such as an ethylene-1-butene copolymer is partially or entirely adsorbed on the surface of the conductive nanofiller (A) in an organic solvent such as chloroform. The dispersibility of the conductive nanofiller (A) can be improved, and by distilling off the solvent after adsorbing a part or all of these copolymers on the surface of the conductive nanofiller (A), A composite in which these ethylene copolymers are adsorbed on the conductive nanofiller (A) can be prepared and used in the resin composition of the present invention. By adsorbing a high affinity resin (B _aff ) such as ethylene-1-butene copolymer on the surface of the conductive nanofiller (A), for example, in the mixing step at the time of producing the resin composition, the conductive nanofiller There is a tendency that the wettability of the interface between (A) and the high affinity resin (B _aff ) is improved, and the thermal conductivity and insulation of the resulting resin composition are improved. Examples of such an ethylene-1-butene copolymer include “Toughmer A0550S” manufactured by Mitsui Chemicals, Inc.

  Although there is no restriction | limiting in particular as specific gravity of polyolefin resin used for this invention, 0.85 or more are preferable, 0.90 or more are more preferable, 0.94 or more are further more preferable, 0.95 or more are especially preferable, 0 .96 or more is most preferable. If the specific gravity of the polyolefin resin is less than the lower limit, the thermal conductivity tends to be difficult to improve sufficiently.

In addition, there is no particular limitation on the melt flow rate (measured at 190 ° C. in accordance with MFR, JIS K6922-1) of polyolefin resin when used as a high affinity resin (B _aff ). In view of the above, 0.1 g / 10 min or more is preferable, 0.2 g / 10 min or more is more preferable, 0.3 g / 10 min or more is further preferable, 0.4 g / 10 min or more is particularly preferable, and 0.5 g / 10 min or more is most preferable. preferable. Further, from the viewpoint of forming a more stable disperse phase and improving insulation, it is preferably 100 g / 10 min or less, more preferably 90 g / 10 min or less, and further preferably 80 g / 10 min or less. If the MFR of the polyolefin-based resin is less than the lower limit, the fluidity of the resulting resin composition tends to decrease, and if it exceeds the upper limit, the insulating property tends to decrease.

  As the polyarylene sulfide used in the present invention, a conventionally known polyarylene sulfide can be used. For example, any of a linear polyarylene sulfide, a crosslinked polyarylene sulfide, and a mixture thereof can be used. Among such polyarylene sulfides, p-phenylene sulfide homopolymer and m-phenylene sulfide (co) polymer are preferable.

When used as a high-affinity resin (B _aff ), the polyarylene sulfide has a melt viscosity (temperature: 310 ° C., shear rate: 1200 sec ⁻¹ ), which easily forms a dispersed phase, and contains the conductive nanofiller (A). From the viewpoint that the insulating property is improved as a result of these, it is preferably 2 Pa · s or more, more preferably 5 Pa · s or more, further preferably 10 Pa · s or more, particularly preferably 20 Pa · s or more, and 50 Pa · s. Most preferred is s or more.

  Examples of the polyamide used in the present invention include homopolymers and copolymers obtained mainly from at least one of amino acids, lactams and diamines and dicarboxylic acid. Such a polyamide can be obtained by a known polycondensation reaction.

  Examples of the amino acids include aminocarboxylic acids such as 6-aminocaproic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid. Examples of the lactam include ε-caprolactam and ω-laurolactam. As tetramethylenediamine, hexamethylenediamine, ethylenediamine, trimethylenediamine, pentamethylenediamine, 2-methylpentamethylenediamine, nonanediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, nonamethylenediamine, 5-methylnonamethylenediamine, metaxylylenediamine, paraxylylenediamine, 1,3-bis (aminomethyl) cycle Rhohexane, 1,4-bis (aminomethyl) cyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis (4-aminocyclohexyl) methane, bis (3-methyl-4-aminocyclohexyl) ) Aliphatic, alicyclic or aromatic diamines such as methane, 2,2-bis (4-aminocyclohexyl) propane, bis (aminopropyl) piperazine and aminoethylpiperazine.

  Examples of the dicarboxylic acid include adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, Examples thereof include aliphatic, alicyclic or aromatic dicarboxylic acids such as 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium sulfoisophthalic acid, hexahydroterephthalic acid and hexahydroisophthalic acid.

  Specific examples of such polyamides include polycaprolactam (nylon 6), polyhexamethylene adipamide (nylon 66), polytetramethylene adipamide (nylon 46), polyundecanamide (nylon 11), polydodecanamide (Nylon 12), polyhexamethylene sebacamide (nylon 610), polyhexamethylene azelamide (nylon 69), polyhexamethylene terephthalamide (nylon 6T), nylon 9T, nylon MXD6, nylon 6/66 copolymer, polycapro Amide / polyhexamethylene sebacamide copolymer (nylon 6/610 copolymer), nylon 6 / 6T copolymer, nylon 6/66/610 copolymer, nylon 6/12 copolymer, nylon 6T / 12 copolymer, nylon 6 / 66 copolymer, polycaproamide / polyhexamethylene isophthalamide copolymer (nylon 6 / 6I copolymer), nylon 66 / 6I / 6 copolymer, nylon 6T / 6I copolymer, nylon 6T / 6I / 66 copolymer, nylon 6/66/610 / 12 copolymer, nylon 6T / M-5T copolymer and the like. Among them, from the viewpoint of high affinity with the conductive nanofiller (A), the polyamide for forming the dispersed phase is preferably a polyamide having an aromatic group, such as nylon 6T, nylon 9T, nylon MXD6, nylon 6 / 6T copolymer, nylon 6T / 12 copolymer, nylon 6T / 66 copolymer, nylon 6 / 6I copolymer, nylon 66 / 6I / 6 copolymer, nylon 6T / 6I copolymer, nylon 6T / 6I / 66 copolymer, nylon 6T / M5-T More preferred are copolymers.

  The molecular weight of the polyamide used in the present invention is not particularly limited, but the relative viscosity of a solution obtained by dissolving polyamide in 96% concentrated sulfuric acid at a concentration of 1 g / dl is preferably 1.5 or more at 25 ° C. It is more preferably 1.8 or more, further preferably 1.9 or more, particularly preferably 2.0 or more, preferably 5.0 or less, and 4.5 or less. More preferably. When the relative viscosity is less than the lower limit, the mechanical strength of the resulting resin composition tends to decrease, and when the upper limit is exceeded, the fluidity of the resin composition tends to decrease.

  As an imide ring containing vinyl polymer used for this invention, it may consist only of an imide ring containing structural unit, and may contain an imide ring containing structural unit and another vinyl monomer unit.

  As the imide ring-containing structural unit, the following formula (I):

(In formula (I), R ¹ and R ² each independently represent a hydrogen atom or an alkyl group, and R ³ represents a hydrogen atom, or an alkyl group, an alkynyl group, an aralkyl group, a cycloalkyl group, an aryl group, an amino group, etc. Represents a monovalent organic group of
A maleimide monomer unit represented by the following formula (II):

(In formula (II), R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group, and R ⁶ represents a hydrogen atom, or an alkyl group, an alkynyl group, an aralkyl group, a cycloalkyl group, an aryl group, an amino group, etc. Represents a monovalent organic group of
The glutarimide group containing structural unit etc. which are represented by these are mentioned.

These imide ring-containing structural units may be contained alone or in combination of two or more in the imide ring-containing vinyl polymer. Of these imide ring-containing structural units, maleimide monomer units are preferred, and at least one of N-aryl maleimide monomer units, N-alkyl substituted aryl maleimide monomer units, and N-long chain alkyl maleimide monomer units is present. Particularly preferred. When a vinyl polymer containing these maleimide monomer units is used, the thermal resistance at the interface between the conductive nanofiller (A) and the high affinity resin (B _aff ) in the dispersed phase tends to be reduced.

  Although there is no restriction | limiting in particular as a content rate of the imide ring containing structural unit in the said imide ring containing vinyl polymer, 1 mass% or more is preferable, 20 mass% or more is more preferable, 50 mass% or more is further more preferable, 70 mass % Or more is particularly preferable, and 80% by mass or more is most preferable. When the content of the imide ring-containing structural unit is less than the lower limit, the amount of adsorption to the conductive nanofiller (A) tends to decrease or the adsorption stability tends to decrease. Moreover, the heat resistance of the obtained resin composition tends to decrease, and the anisotropy of thermal conductivity tends not to be sufficiently reduced.

  Other vinyl monomers used to form the other vinyl monomer units include vinyl macromonomers such as polyalkylene oxide group-containing vinyl monomers, polystyrene-containing vinyl monomers, and polysiloxane-containing vinyl monomers. , Polycyclic aromatic group-containing vinyl monomers, unsaturated carboxylic acid ester monomers, vinyl cyanide monomers, aromatic vinyl monomers, unsaturated carboxylic acid monomers, acid anhydrides and derivatives thereof, epoxy group-containing vinyl monomers , Oxazoline group-containing vinyl monomers, amino group-containing vinyl monomers, amide group-containing vinyl monomers, hydroxyl group-containing vinyl monomers, siloxane structure-containing vinyl monomers, silyl group-containing vinyl monomers, and oxetanyl groups Such as organic vinyl monomer. These vinyl monomers may be used alone or in combination of two or more.

  In addition to the other vinyl monomers, for example, olefin monomers, vinyl halide monomers, carboxylic acid unsaturated ester monomers, vinyl ether monomers, cationic vinyl monomers, anionic vinyl monomers, zwitterionic monomers Such vinyl monomers can also be used. These monomers may be used alone or in combination of two or more.

  The polycyclic aromatic group-containing polymer used in the present invention may be composed only of a polycyclic aromatic group-containing vinyl monomer unit, or a polycyclic aromatic group-containing vinyl monomer unit and other vinyl monomers. The unit may further include an imide ring-containing structural unit.

  Examples of the polycyclic aromatic group-containing vinyl monomer unit include those in which a polycyclic aromatic group is bonded to the vinyl monomer unit directly or through a divalent organic group, or polyamides to the amide group-containing vinyl monomer unit. Examples include those in which an aromatic group is bonded directly or via a divalent organic group. Among these, the following formula (III):

The polycyclic aromatic group containing vinyl-type monomer unit represented by these is preferable. In the formula (III), R ⁷ represents a divalent organic group having 1 to 20 carbon atoms, R ⁸ represents a monovalent polycyclic aromatic-containing group, and R ⁹ , R ¹⁰ and R ¹¹ each represents Independently represents hydrogen or a monovalent organic group having 1 to 20 carbon atoms.

R ⁷ is preferably a divalent organic group having 1 to 20 carbon atoms, and methylene, ethylene, propylene, butylene, pentamethylene, hexamethylene, and one or more hydrogen atoms thereof as other atoms. Substituted substituted products are more preferable, and butylene is particularly preferable from the viewpoints of the adsorptivity and adsorption stability to the conductive nanofiller (A) and the polymerization reactivity during production by copolymerization. R ⁸ is preferably naphthyl, naphthalenyl, anthracenyl, pyrenyl, terphenyl, perylenyl, phenanthrenyl, tetracenyl, pentacenyl, or a substituent in which one or two or more hydrogen atoms thereof are substituted with other atoms. Pyrenyl is particularly preferable from the viewpoint of adsorptivity to the nanofiller (A) and adsorption stability. R ⁹ and R ¹⁰ are preferably a hydrogen atom, an alkyl ester group, a carboxyl group and a carboxylate anion group, and particularly preferably a hydrogen atom. R ¹¹ is preferably a hydrogen atom, a methyl group, an alkyl ester group or a carboxyl group, particularly preferably a hydrogen atom or a methyl group. In the present invention, such a polycyclic aromatic group-containing vinyl monomer unit may be contained singly or in combination of two or more.

  The content of the polycyclic aromatic group-containing vinyl monomer unit in the polycyclic aromatic group-containing vinyl polymer is not particularly limited, but is preferably 0.1% by mass or more, more preferably 1% by mass or more, 10 mass% or more is especially preferable, and 20 mass% or more is the most preferable. When the content of the polycyclic aromatic group-containing vinyl monomer unit is less than the lower limit, the amount of adsorption to the conductive nanofiller (A) tends to decrease or the adsorption stability tends to decrease. Further, the anisotropy of the thermal conductivity of the obtained resin composition tends not to be sufficiently reduced.

  Examples of other vinyl monomers used for forming the other vinyl monomer units include the vinyl monomers exemplified in the imide ring-containing vinyl polymer.

In the resin composition of the present invention, the lower limit of the content of the resin (B _aff ) having the highest affinity with the conductive nanofiller (A) is not particularly limited, but 1% by volume relative to the entire resin composition The above is preferable, 3% by volume or more is more preferable, 5% by volume or more is further preferable, 10% by volume or more is particularly preferable, and 14% by volume or more is most preferable. The upper limit of the content of the high affinity resin (B _aff), is not particularly limited as long as the dispersed phase is formed by the high affinity resin (B _aff), preferably 70 volume% or less, 60 More preferably, it is 50% by volume or less, particularly preferably 40% by volume or less, and most preferably 30% by volume or less. When the content of the high-affinity resin (B _aff ) is less than the lower limit, the thermal conductivity and the insulating properties are hardly improved sufficiently, and the anisotropy of the thermal conductivity tends to be hardly reduced, When the upper limit is exceeded, a dispersed phase due to the high affinity resin (B _aff ) is hardly formed, and the insulating property tends to decrease.

Of the two or more kinds of resins (B) used in the present invention, the other resin (B1) other than the high-affinity resin (B _aff ) is not particularly limited, and among those exemplified as the resin (B) Resins other than those used as the high-affinity resin (B _aff ) can be suitably used, but crystalline resins are preferred from the viewpoint of improving thermal conductivity, and viewpoints of further improving heat resistance. The crystalline resin having a melting point of 160 ° C or higher is more preferable, the crystalline resin having a melting point of 200 ° C or higher is more preferable, the crystalline resin having a melting point of 220 ° C or higher is particularly preferable, and the crystalline resin having a melting point of 250 ° C or higher is preferable. Most preferred. Examples of such a crystalline resin include polyarylene sulfide (melting point 280 ° C.), polyacetal (melting point 165 ° C.), polyamide (melting point 170 ° C. or higher), polyester resin (melting point 224 ° C. or higher), liquid crystal polyester (melting point 280). ° C or higher).

When polyarylene sulfide is used as the resin (B1), its melt viscosity (temperature: 310 ° C., shear rate: 1200 sec ⁻¹ ) is 3000 Pa · s from the viewpoint of easily forming a continuous phase and improving insulation. Or less, more preferably 1000 Pa · s or less, even more preferably 300 Pa · s or less, particularly preferably 100 Pa · s or less, and most preferably 50 Pa · s or less. The lower limit of the melt viscosity of the polyarylene sulfide is not particularly limited, but is preferably 1 Pa · s or more, more preferably 3 Pa · s or more, and more preferably 5 Pa · s or more from the viewpoint of mechanical properties of the obtained resin composition. Is more preferable, and 10 Pa · s or more is particularly preferable. In the present invention, it is also preferable to use a mixture of a plurality of polyarylene sulfides having different melt viscosities.

  In the resin composition of the present invention, the content of the other resin (B1) is not particularly limited, but is preferably 25% by volume or more, more preferably 30% by volume or more, and 40% by volume with respect to the entire resin composition. More preferably, 50% by volume or more is particularly preferable, 60% by volume or more is most preferable, 98% by volume or less is preferable, 96% by volume or less is more preferable, 94% by volume or less is further preferable, and 90% by volume or less is preferable. Is particularly preferred, with 85% by volume or less being most preferred. When the content of the other resin (B1) is less than the lower limit, it is difficult to form a continuous phase due to the other resin (B1), and the insulating property tends to be lowered. Tend to decrease.

(C) Compound having functional group The compound having a functional group used in the present invention (hereinafter referred to as “functional group-containing compound (C)”) is a conductive nanofiller compared to the high affinity resin (B _aff ). (A) has low affinity and has affinity and / or reactivity with the high affinity resin (B _aff ) and the other resin (B1). Among them, the high affinity resin ( B _aff ) and those having reactivity with the other resin (B1) are preferable. By using such a functional group-containing compound (C), the conductive nanofiller (A) is localized in the dispersed phase formed by the high affinity resin (B _aff ). In the present invention, when the functional group-containing compound (C) is reacted with the resin (B) (that is, the high affinity resin (B _aff ) and / or other resin (B1)). The reaction product is also included in the functional group-containing compound (C) according to the present invention.

  In the resin composition of the present invention, it is preferable that at least a part of the functional group-containing compound (C) (including the reaction product thereof) is present at the interface between the dispersed phase and the continuous phase. Thereby, the functional group-containing compound (C) acts as a shell of the dispersed phase, and the conductive nanofiller (A) can be stably localized in the dispersed phase. In addition, at least a part of the conductive nanofiller (A) in the dispersed phase is exposed to the outside of the dispersed phase to prevent contact with the conductive nanofiller (A) in the continuous phase to form an electrically conductive path. Can do. Furthermore, the thermal resistance of the interface is reduced, the thermal conductivity of the resin composition is improved, and the insulating property of the interface tends to be improved. Furthermore, the formation of the interface suppresses the continuous phase of the dispersed phase caused by stretching or joining the dispersed phase by processing under shear such as injection molding, and the flow of the conductive nanofiller (A). The orientation in the direction tends to be reduced, and the anisotropy of various characteristics such as thermal conductivity tends to be reduced.

  When the functional group-containing compound (C) forms a dispersed phase, the reaction product with the functional group-containing compound (C), particularly the resin (B) has a low affinity with the conductive filler (A). The conductive filler (A) is difficult to be taken into the dispersed phase, and it is difficult to improve insulation and thermal conductivity.

  As such a functional group-containing compound (C), from the viewpoint of high affinity and / or reactivity with the other resin (B1), an alkoxysilyl group, a silanol group, an epoxy group, an isocyanate group, an amino group, A compound having at least one functional group selected from the group consisting of a hydroxyl group, a mercapto group, a ureido group, a carboxyl group, a carboxylic anhydride group, an oxetane group and an oxazoline group is preferred.

  Specific examples of such a functional group-containing compound (C) include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. Such as epoxy group-containing alkoxysilane compounds; N-diglycidyl-N, N-bis (3- (methyldimethoxysilyl) propyl) amine, N-diglycidyl-N, N-bis (3- (trimethoxysilyl) propyl) amine, etc. An amine compound containing an epoxy group and an alkoxysilyl group; an alkoxysilyl group-containing isocyanate compound such as 3- (trimethoxysilyl) propyl isocyanate and 3- (triethoxysilyl) propyl isocyanate; 1,3,5-N -Tris (3-triethoxysilyl Propyl) isocyanurate, 1,3,5-N-tris (3-methyldimethoxysilylpropyl) isocyanurate, 1,3,5-N-tris (3-trimethoxysilylpropyl) isocyanurate Nurate compounds; 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltri Ethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldiethoxysilane, 3- (N-phenyl) aminopropyltrimethoxysilane , 3- (N-phenyl) aminopropyltri Amino group-containing alkoxysilane compounds such as toxisilane; alkoxysilyl group-containing vinyl compounds such as vinyltriethoxysilane; halosilanes and polyhalosilanes such as chlorosilane and bromosilane; N, N-bis (3- (trimethoxysilyl) propyl) amine, N, N- Multiple alkoxysilyl groups such as bis (3- (trimethoxysilyl) propyl) ethylenediamine, N, N-bis ((methyldimethoxysilyl) propyl) amine, N, N-bis (3- (methyldimethoxylyl) propyl) ethylenediamine N, N-bis (3- (trimethoxysilyl) propyl) methacrylamide, N, N-bis (3- (trimethoxysilyl) propyl) acrylamide, N, N-bis ((methyldimethoxy) Cyril ) Propyl) alkoxysilyl group-containing amide compounds such as methacrylamide; alkoxysilyl group-containing polysulfanes such as bis (3-triethoxysilylpropyl) polysulfane and bis (triethoxysilylethyltolylene) polysulfane; methylmethoxysilicone Silicone oligomers such as oligomers and dimethoxysilicone oligomers; Alkoxysilyl group-containing polyolefins such as alkoxysilyl group-containing polyethylene and alkoxysilyl group-containing polypropylene; Silanol group-modified polyethylene, silanol group-modified polypropylene, silanol group-modified ethylene-propylene copolymer, silanol group-modified Silanol group-modified polyolefin such as ethylene-propylene-diene copolymer; bisphenol A-diglycy Bisphenol A type epoxy compounds such as bisphenol F; bisphenol F type epoxy compounds such as bisphenol F-diglycidyl ether; bisphenol AD type epoxy compounds such as bisphenol AD-diglycidyl ether; glycidyl ester type epoxy compounds such as glycidyl phthalate; N-glycidyl aniline, etc. Glycidylamine epoxy compounds; novolac epoxy resins such as phenol novolac type epoxy resins and cresol novolac type epoxy resins; epoxy group containing polyolefins such as epoxy group containing polyethylene and epoxy group containing polypropylene; epoxy group containing polymethyl methacrylate, epoxy group containing acrylonitrile -Styrene copolymer, epoxy group-containing acrylic elastomer An epoxy group-containing vinyl polymer and the like such mer.

  Bisphenol A, bisphenol F, bisphenol AD, bisphenol S, resorcinol, hydroquinone, pyrocatechol, diphenyldimethylmethane, 4,4′-dihydroxybiphenyl, 1,3,5-trihydroxybenzene, 1,5-dihydroxynaphthalene, Cashew phenol, 2,2,5,5-tetrakis (4-hydroxyphenyl) hexane, salicyl alcohol, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-octanoylthio-1-propyltrimethoxysilane, 3-octanoylthio-1-propyltriethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3- (2-ureidoethyl) aminopro Le trimethoxysilane, 3- well as (2-ureidoethyl) aminopropyl triethoxysilane can be used as a functional group-containing compound according to the present invention (C).

Such a functional group containing compound (C) may be used individually by 1 type, or may use 2 or more types together. In the present invention, the interface between the dispersed phase and the continuous phase is strengthened, and a phase structure in which the conductive nanofiller (A) is highly localized (localized) in the dispersed phase is formed. From the viewpoint of improving the mechanical strength of the functional group-containing compound (C), the alkoxysilyl group, silanol group, epoxy group, isocyanate group, amino group, hydroxyl group, mercapto group, ureido group, carboxyl group, carboxylic anhydride A compound having at least two functional groups selected from the group consisting of a physical group, an oxetane group and an oxazoline group is preferred, and an alkoxysilyl group, a silanol group, an epoxy group, an isocyanate group, an amino group, a carboxyl group, and a carboxylic acid anhydride More preferred is a compound having at least two functional groups selected from the group consisting of groups. Group, a silanol group, a compound having at least two functional groups selected from the group consisting of an epoxy group and an isocyanate group are particularly preferred. This is because the functional group-containing compound (C) has two or more functional groups, so that it reacts with a high affinity resin (B _aff ) and / or other resin (B1) as described later and contains a functional group. A cross-linking reaction between the compounds (C) (including the reaction product) occurs, and a thicker and stronger interface layer is formed. As a result, the conductive nanofiller (A) is effectively included in the dispersed phase. In addition, the insulation is further improved and the thermal resistance at the interface is further reduced. Further, in the resin composition of the present invention, in order to improve the strength of the interface layer, an amine curing agent, an imidazole curing agent, a polymercaptan curing agent, an acid anhydride, a light / ultraviolet curing agent, etc. It is preferable to add a known curing accelerator.

  In the resin composition of the present invention, the content of the functional group-containing compound (C) is not particularly limited, but is preferably 0.01% by volume or more, more preferably 0.05% by volume or more with respect to the entire resin composition. Preferably, 0.1% by volume or more is more preferable, 0.2% by volume or more is particularly preferable, 60% by volume or less is preferable, 50% by volume or less is more preferable, 40% by volume or less is further preferable, and 20% by volume. The following are particularly preferred: When the content of the functional group-containing compound (C) is less than the lower limit, the anisotropy of thermal conductivity is not sufficiently reduced, and in particular, the insulating property tends not to be sufficiently secured, and on the other hand, exceeds the upper limit. And the molding processability of the resin composition tends to decrease.

(D) Filler In the resin composition of this invention, you may contain a filler (D) as needed. Thereby, the intensity | strength of the resin composition obtained, rigidity, heat resistance, heat conductivity, etc. can be improved. Such filler (D) may be fibrous or non-fibrous such as granular. Specific examples thereof include glass fibers, carbon fibers, metal fibers, aramid fibers, cellulose fibers, asbestos, potassium titanate whiskers, wollastonite, glass flakes, glass beads, talc, clay minerals represented by montmorillonite, mica (mica) ) Layered silicates represented by minerals and kaolin minerals, silica, calcium carbonate, magnesium carbonate, silicon oxide, calcium oxide, zirconium oxide, calcium sulfate, barium sulfate, titanium oxide, aluminum oxide and dolomite. The content of the filler in the resin composition of the present invention varies depending on the type of filler, and thus cannot be specified unconditionally. For example, it is preferably 0.05% by volume or more with respect to the entire resin composition, 0.1% % By volume or more is more preferable, 1% by volume or more is more preferable, 90% by volume or less is preferable, 80% by volume or less is more preferable, 70% by volume or less is further preferable, and 60% by volume or less is particularly preferable.

  Moreover, the resin composition of this invention can also be made to contain a heat conductive filler as a filler (D). Such a thermally conductive filler is not particularly limited, and examples thereof include alumina, boron nitride, aluminum nitride, silicon nitride, silicon carbide, crystalline silica, fused silica, diamond, and zinc oxide. There is no restriction | limiting in particular as these shapes, For example, granular, flat form, rod shape, fiber shape, tube shape etc. are mentioned. These thermally conductive fillers may be used alone or in combination of two or more. Although there is no restriction | limiting in particular as thermal conductivity of this heat conductive filler, 0.5 W / mK or more is preferable, 1 W / mK or more is more preferable, 5 W / mK or more is further more preferable, 10 W / mK or more is especially preferable, 10 W / mK or more is most preferable.

  The content of the heat conductive filler in the resin composition of the present invention is not particularly limited, but it is preferably 0.1% by volume or more, preferably 90% by volume or less, and 80% by volume or less with respect to the entire resin composition. Is more preferably 70% by volume or less, particularly preferably 50% by volume or less, and most preferably 40% by volume or less. If the content of the thermally conductive filler is less than the lower limit, the thermal conductivity of the resulting molded product tends not to be sufficiently improved. On the other hand, if the upper limit is exceeded, the specific gravity of the resin composition increases and the fluidity decreases. It tends to be easy to do.

(Other additives)
The resin composition of the present invention contains a conductive material such as a conductive polymer such as polyaniline, polypyrrole, polyacetylene, poly (paraphenylene), polythiophene and polyphenylene vinylene, and a filler coated with the conductive material. You can also. Although there is no restriction | limiting in particular as addition amount of such a conductive substance and the filler coat | covered with a conductive substance, It exists in the range which can maintain insulation (The volume resistivity is preferably 10 < ¹³ > ohm * cm or more). Is preferred. In addition, the dispersion state of the conductive material and the filler coated with the conductive material is not particularly limited. However, from the viewpoint of obtaining the effect of the addition of these while maintaining the insulating property, at least one of these is preferable. Is preferably contained in the dispersed phase formed by the high affinity resin (B _aff ), and more than half of the amount added is contained in the dispersed phase formed by the high affinity resin (B _aff ). More preferably it is included.

  The resin composition of the present invention includes other components such as metal salt stabilizers such as copper chloride, cuprous iodide, copper acetate, cerium stearate, hindered amines, hindered phenols, and sulfur-containing compounds. -Based, acrylate-based, phosphorus-based organic compounds and other antioxidants, heat stabilizers, benzophenone-based, salicylate-based, benzotriazole-based UV absorbers and weathering agents, light stabilizers, mold release agents, lubricants, crystal nucleating agents , Surface treatment agents such as viscosity modifiers, colorants, silane coupling agents, pigments, fluorescent pigments, dyes, fluorescent dyes, anti-coloring agents, plasticizers, flame retardants (red phosphorus, metal hydroxide flame retardants, phosphorus Flame retardants, silicone flame retardants, halogen flame retardants, and combinations of these halogen flame retardants and antimony trioxide), wood powder, rice bran powder, walnut powder, waste paper, storage Pigments, antibacterial agents and antifungal agents such as boric acid glass and silver-based antibacterial agent, magnesium - may be added to a mold corrosion inhibitor such as hydrotalcite represented by aluminum hydroxy hydrate.

<Resin composition and production method thereof>
Next, the manufacturing method of the resin composition of this invention is demonstrated. Examples of the method for producing the resin composition of the present invention include a conductive nanofiller (A), a resin (B _aff ) having the highest affinity with the conductive nanofiller (A), other resins (B1), Method of mixing functional group-containing compound (C) and, if necessary, filler (D) and other additives and then mixing by melt kneading using an extruder; melting using a Banbury mixer or rubber roll machine The method of mixing by kneading is mentioned. The extruder is not particularly limited as long as it has a sufficient kneading ability, and includes an extruder having a uniaxial or multiaxial vent. The shape of each component is not particularly limited, and any shape such as pellets, powders, and strips may be used.

In the method for producing a resin composition of the present invention, the above components may be mixed together, but the phase structure according to the present invention is suitably formed, and the resulting resin composition has thermal conductivity and insulating properties. From the standpoint of combining, it is preferable to mix specific components in advance, and then mix the remaining components. In particular, at least a part (preferably all) of the conductive nanofiller (A) and a high-affinity resin (B _aff ) At least a part (preferably all) of the mixture, and then the resulting mixture and the remaining components (other resin (B1), functional group-containing compound (C), and, if necessary, a filler (D ) And other additives), or at least a part (preferably all) of the conductive nanofiller (A) and at least a part (preferably all) of the high affinity resin (B _aff ) and functional Base After the organic compound (C) is mixed at least in part (preferably all) in advance, the resulting mixture and the remaining components (other resin (B1), and filler (D) and other additions as necessary It is preferable to mix the agent.

In these production methods, the conductive nanofiller (A), the high affinity resin (B _aff ), and (in the latter case, the functional group-containing compound (C)) are previously melt-kneaded using an extruder or the like. After the mixing, etc., the remaining components may be added and mixed by melt kneading or the like, or the conductive nanofiller (A) and the high affinity resin (B _aff ) (in the latter case, further containing a functional group) Compound (C)) is melted and kneaded in advance from a hopper upstream of an extruder equipped with one or more side feeders, and then each of the remaining components is melted by feeding from one or more side feeders. Kneading may be performed. Further, among the remaining components, the filler (D) and other additives are downstream from the charging port for charging the other resin (B1) from the viewpoint of improving mechanical properties and thermal conductivity. It is also preferable to add from the side feeder, and it is also preferable to add it separately using a single screw extruder or a twin screw extruder set in a screw arrangement with weak kneading ability.

<Phase structure>
As described above, the resin composition of the present invention thus prepared includes a dispersed phase formed from the high affinity resin (B _aff ) and a continuous phase formed from the other resin (B1). The conductive nanofiller (A) is present in the dispersed phase, and at least a part of the functional group-containing compound (C) is present at the interface between the dispersed phase and the continuous phase. preferable. This tends to improve thermal conductivity and insulation. In the resin composition of the present invention, the dispersed phase means a portion in which the high affinity resin (B _aff ) is surrounded by the other resin (B 1).

Although there is no restriction | limiting in particular as thermal conductivity of the resin composition of this invention provided with such a phase structure, 0.3 W / mK or more is preferable, 0.4 W / mK or more is more preferable, 0.5 W / mK or more Is particularly preferable, and 0.6 W / mK or more is most preferable. The volume resistivity is not particularly limited, but is preferably 10 ¹³ Ω · cm or more, more preferably 10 ¹⁴ Ω · cm or more, particularly preferably 10 ¹⁵ Ω · cm or more, and most preferably 10 ¹⁶ Ω · cm or more. preferable.

  The thermal conductivity is a value measured by the following method. That is, after the pellet-shaped resin composition is vacuum-dried under predetermined conditions (for example, conditions shown in Table 1), press molding is performed under predetermined molding conditions (for example, conditions shown in Table 1), and molding with a thickness of 2 mm is performed. Make a product. A 25 mm × 25 mm × 2 mm sample was cut out from this molded product, and was used at 40 ° C. (upper / lower temperature difference of 24 ° C.) using a steady-state thermal conductivity measuring device (for example, “GH-1” manufactured by ULVAC-RIKO Co., Ltd.). The thermal conductivity (W / mK) in the thickness direction of the sample is measured. The volume resistivity is a value measured by the following method. That is, after the pellet-shaped resin composition is vacuum-dried under predetermined conditions (for example, conditions shown in Table 1), press molding is performed under predetermined molding conditions (for example, conditions shown in Table 1), and molding with a thickness of 2 mm is performed. Make a product. A disk-shaped sample having a diameter of 100 mm and a thickness of 2 mm was cut out from the molded product, and a high resistance meter (for example, “AGILENT 4339B” manufactured by Agilent Technologies, Inc.) was used to apply 500 V in accordance with JIS K6911. The subsequent volume resistivity is measured.

1A to 1C schematically show the phase structure of such a resin composition, but the phase structure of the resin composition of the present invention is not limited to this. The dispersed phase 3 is formed of a resin (B _aff ) having the highest affinity with the conductive nanofiller (A). In this case, as long as the disperse phase 3 and the continuous phase 4 are formed, other resins having affinity with the conductive nanofiller (A) and resins (B1) other than the resin having the highest affinity (B _aff ) are available. It may be contained in the dispersed phase 3. The number of conductive nanofillers (A _dsp ) 1 included in one dispersed phase 3 is not particularly limited, and may be one as shown in FIG. 1A or plural as shown in FIG. 1B. Furthermore, when there are a plurality of conductive nanofillers (A _dsp ) 1 in the dispersed phase 3, the dispersion state is not particularly limited, and the conductive nano fillers (A _dsp ) 1 are in contact even if they are in contact with each other. 1B, it may be completely isolated and dispersed as shown in FIG. 1B, or may be completely in contact with each other as shown in FIG. 1C, but the thermal conductivity anisotropy is reduced. From this viewpoint, it is preferable that the major axis direction of each conductive nanofiller (A _dsp ) 1 exists more three-dimensionally. In the resin composition of the present invention, two or more states among the states shown in FIGS. 1A to 1C may be mixed. The shape of the dispersed phase 3 is not particularly limited, and may be a perfect circle or a non-circular shape such as a stripe shape, a polygonal shape, or an elliptical shape.

The continuous phase 4 is formed of one or more kinds of resins (B1) other than the high affinity resin (B _aff ). However, as long as the dispersed phase 3 and the continuous phase 4 are formed, the high affinity is used. Resin (B _aff ) may be included. The continuous phase 4 may contain the conductive nanofiller (A). However, in applications where insulation is required, the content is preferably the insulating property (volume resistivity is preferred) of the resin composition. Is preferably in a range where 10 ¹³ Ω · cm or more is maintained.

In the resin composition of the present invention, at least a part (more preferably all) of the functional group-containing compound (C) is present at the interface between the dispersed phase 3 and the continuous phase 4, and this acts as a shell of the dispersed phase 3. It is preferable. Thus, when the functional group-containing compound (C) acts as a shell of the dispersed phase 3, the conductive nanofiller (A) is localized in the dispersed phase 3, and the tendency to be included is increased. Further, the conductive nanofiller (A _dsp ) in the dispersed phase 3 is exposed to the outside of the dispersed phase 3 at the time of melt processing and comes into contact with the conductive nanofiller (A) in the continuous phase 4 to form an electric conduction path. Can be prevented. Furthermore, the thermal resistance of the interface is further reduced, the thermal conductivity of the resin composition is further improved, and the insulating property of the interface is further improved. Also, the anisotropy of various properties such as thermal conductivity tends to be smaller.

In the case where a resin having a reactive functional group such as a terminal reactive group is used as at least one of the two or more kinds of resins (B), from the viewpoint of improving thermal conductivity, the functional group At least a part (preferably all) of the functional groups of the containing compound (C) binds to the reactive functional groups in the high affinity resin (B _aff ) and / or the other resin (B 1) by a chemical reaction. It is preferable. Thereby, a stable layer is formed at the interface between the dispersed phase and the continuous phase, and the conductive nanofiller (A) can be stably encapsulated in the dispersed phase. In addition, at the interface between the dispersed phase and the continuous phase, it is more preferable that the functional group-containing compound (C) and / or the reaction product thereof react with each other. As a result, the layer formed at the interface between the dispersed phase and the continuous phase becomes thicker and stronger, and the insulating property is further improved, and the thermal resistance at the interface is further reduced (thermal conductivity is further improved). It is in.

  For example, when polyphenylene sulfide is used as the dispersed phase and polyamide is used as the continuous phase, the functional group-containing compound (C) is at least two selected from the group consisting of alkoxysilyl groups, silanol groups, epoxy groups and isocyanate groups. The compound having a functional group is preferably an epoxy group-containing alkoxysilane compound (particularly preferably, 3-glycidyloxypropyltrimethoxysilane) or an alkoxysilyl group-containing isocyanate ester compound (particularly preferably, 3- (triethoxy isocyanate). More preferred is at least one compound selected from (silyl) propyl) and epoxy group-containing polyolefins (particularly preferably epoxy-modified polyethylene). Thereby, an SNa group which is a terminal group of polyphenylene sulfide, an SH group generated by acid treatment or the like from the SNa group, an amino group, a carboxyl group, an acid anhydride group introduced by production or after-treatment as necessary, End groups formed by reaction of epoxy groups or N-methylpyrrolidone used during production, and amino groups, carboxyl groups, and amide groups of the main chain, which are polyamide end groups, are functional during processing such as melt kneading. It reacts with the functional group of the group-containing compound (C) to form a stable interface layer. As a result, the conductive nanofiller (A) is stably encapsulated in the dispersed phase formed of polyphenylene sulfide. In the interface layer, a cross-linking reaction such as a reaction between the alkoxysilyl group and silanol group of the functional group-containing compound (C) and / or its reaction product (polysiloxane structure formation reaction) or an epoxy group reaction occurs. And the interface layer becomes thicker and stronger, the conductive nanofiller (A) is effectively included in the dispersed phase, the insulation is further improved, and the thermal resistance of the interface is further reduced. There is a tendency.

The phase structure of such a resin composition can be confirmed by observing with a scanning electron microscope or a transmission electron microscope. In particular, when a reaction product is formed at the interface by the reaction between the functional group-containing compound (C) and the high affinity resin (B _aff ) and / or other resin (B 1), the reaction product is formed. The interface layer to be formed can be confirmed by observation using a transmission electron microscope or a scanning force microscope (for example, elastic modulus mode).

In the resin composition of the present invention, the ratio of the dispersed phase to the entire resin composition is X (unit: volume%), and the conductive nanofiller (A) contained in the dispersed phase with respect to the total conductive nanofiller (A). _When the ratio of _{dsp 1} is Y (unit: volume%), the ratio (Y / X) is 1.2 or more. When the Y / X value is less than the lower limit, the insulating property is lowered. Further, from the viewpoint that the insulating property is easily improved, the Y / X value is preferably 1.5 or more, more preferably 1.8 or more, further preferably 2.0 or more, particularly preferably 2.2 or more. .4 or more is most preferable.

The ratio Y of the conductive nanofiller (A _dsp ) contained in the dispersed phase with respect to the total conductive nanofiller (A) is 20% by volume or more. When the ratio Y is less than the lower limit, the thermal conductivity and the insulating properties are lowered. Further, from the viewpoint of easy improvement in thermal conductivity and insulation, Y is preferably 40% by volume or more, more preferably 50% by volume or more, further preferably 60% by volume or more, particularly preferably 80% by volume or more, 100 Volume% is most preferred.

Furthermore, in the resin composition of the present invention, the ratio Z of the dispersed phase containing the conductive nanofiller (A _dsp ) with respect to the entire resin composition is not particularly limited, but is preferably 1% by volume or more, and preferably 3% by volume or more. Is more preferably 5% by volume or more, particularly preferably 7% by volume or more, most preferably 10% by volume or more, more preferably 85% by volume or less, more preferably 80% by volume or less, and more preferably 70% by volume or less. More preferred is 60% by volume or less, and most preferred is 50% by volume or less. When the ratio Z is less than the lower limit, the thermal conductivity and the insulating properties tend to decrease and the anisotropy of the thermal conductivity tends to increase. On the other hand, when the ratio exceeds the upper limit, the fluidity of the resin composition tends to decrease. It is in.

Further, in the resin composition of the present invention, the functional group-containing compound (C) (high affinity resin (B _aff ) and / or others present at the interface between the dispersed phase and the continuous phase with respect to the total functional group-containing compound (C). The proportion W of the resin (including those reacted with the resin (B1)) is not particularly limited, but is preferably 20% by volume or more, more preferably 50% by volume or more, still more preferably 60% by volume or more, and 80% by volume. % Or more is particularly preferable, and 100% by volume is most preferable. When the ratio W is less than the lower limit, the insulating property is lowered and the anisotropy of thermal conductivity tends to increase.

  In the present invention, the values of W, X, Y, and Z are values obtained based on scanning electron microscope (SEM) photographs as follows. That is, a molded product having a predetermined thickness is prepared from the resin composition of the present invention, and an arbitrary part of the center portion (a range of 40 to 60% of the total thickness from the surface) of this molded product is scanned. The image is taken using an electron microscope (SEM) and developed on a photographic paper having a uniform thickness. In the obtained SEM photograph, the range of 90 μm × 90 μm is arbitrarily extracted at five locations in the size of the molded product. Measure the mass of this extracted range, cut out a predetermined part (carbon-based nanofiller, dispersed phase, etc.) from this extracted range, measure the mass of the photo of the cut out part, and measure the mass ratio of the photo for the predetermined part (Mass%) is calculated. The mass ratio of this photograph can be regarded as the actual volume ratio (capacity%) of the predetermined portion because the thickness of the used photographic paper is uniform. This capacity ratio is obtained for any of the five extracted locations, and the average value is defined as the value of W, X, Y or Z (capacity%).

  In the resin composition of the present invention, the number average value of the diameter or major axis of the dispersed phase is not particularly limited, but is preferably 50 nm or more, more preferably 100 nm or more, further preferably 500 nm or more, particularly preferably 1 μm or more. 2 μm or more is most preferable, 200 μm or less is preferable, and 100 μm or less is more preferable. When the number average value of the diameter or the major axis of the dispersed phase is less than the lower limit, the thermal conductivity and the insulating properties tend to be lowered, and the anisotropy of the thermal conductivity tends to increase. On the other hand, when the upper limit is exceeded, the resin composition The mechanical strength of the steel tends to decrease.

Furthermore, when at least a part of the functional group-containing compound (C) is present at the interface between the dispersed phase and the continuous phase, the functional group-containing compound (C) and the high affinity resin (B _aff ) and / or other resins ( The thickness of the reaction product with B1) is not particularly limited, but is preferably 1 nm or more, more preferably 5 nm or more, further preferably 10 nm or more, particularly preferably 20 nm or more, and most preferably 50 nm or more. When the thickness of the reaction product is less than the lower limit, the insulating property is lowered and the anisotropy of thermal conductivity tends to increase.

  In the present invention, the diameter or the major axis of the dispersed phase and the thickness of the reaction product are measured by arbitrarily extracting five ranges of 90 μm × 90 μm in terms of the size of the molded product in an electron micrograph. It is a value obtained by averaging the measured values.

  Although there is no restriction | limiting in particular as a method of processing such a resin composition of this invention into a molded object, A melt molding process is preferable. Examples of the melt molding method include conventionally known molding methods such as injection molding, extrusion molding, blow molding, press molding, compression molding, and gas assist molding. In addition, the orientation of the conductive nanofiller (A) or the resin (B) can be controlled by applying a magnetic field, an electric field, an ultrasonic wave, or the like during the molding process.

  In addition, the resin composition of the present invention hardly exhibits anisotropy in various characteristics (for example, thermal conductivity) even when processed under shear. Here, under shear means a state in which a force (shearing force) that causes displacement inside the object is applied, and examples of processing under shear include injection molding, extrusion molding, and blow molding. It is done. For example, when a resin composition is injection molded, when the resin composition is extruded from a nozzle of an injection molding machine, a force parallel to and opposite to the discharge direction (flow direction) is applied to the resin composition. Slip or slip occurs in the cross section. As a result, in the conventional resin composition not containing the functional group-containing compound (C), the conductive nanofiller (A) is oriented in the flow direction, and various properties (for example, thermal conductivity) are obtained in the obtained molded body. Anisotropy develops in On the other hand, in the resin composition of the present invention, since the dispersed phase containing the conductive nanofiller (A) is dispersed in a nearly three-dimensionally uniform state, the conductive nanofiller can be processed even when processed under shear. The filler (A) is difficult to be oriented, and in the resulting molded body, anisotropy is hardly exhibited in various properties (for example, thermal conductivity), and the properties such as thermal conductivity tend to be nearly three-dimensionally uniform. It is in.

  In addition, compared with injection molding, the shear force at the time of press molding is remarkably small, and in the press-molded product, the orientation of the conductive nanofiller and the resin is extremely small. For this reason, the anisotropy of various characteristics is extremely small in the press-formed product. Therefore, in the present invention, the ratio of the physical property value (for example, thermal conductivity) in the thickness direction of the injection molded product to the physical property value (for example, thermal conductivity) in the thickness direction of the press molded product is obtained, and this physical property value is obtained. The anisotropy of characteristics (for example, thermal conductivity) expressed by the resin composition is quantitatively evaluated based on the ratio. For example, it can be said that a resin composition having a ratio of the physical property values closer to 1 has smaller anisotropy in properties such as thermal conductivity and is nearly three-dimensionally uniform.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example. In addition, the physical property of the obtained resin composition was measured with the following method.

(1) Volume resistivity After pellet-shaped resin composition was vacuum-dried on the conditions shown in Table 1, press molding was performed on the molding conditions shown in Table 1, and the molded article of thickness 2mm was obtained. A disc-shaped sample having a diameter of 100 mm and a thickness of 2 mm was cut out from this molded product, and 500 V was applied in accordance with JIS K6911 using a high resistance meter (“AGILENT 4339B” manufactured by Agilent Technologies) after 1 minute. Volume resistivity was measured.

(2) Thermal conductivity After the pellet-shaped resin composition was vacuum dried under the conditions shown in Table 1, press molding was performed under the molding conditions shown in Table 1 to obtain a molded product having a thickness of 2 mm. A 25 mm × 25 mm × 2 mm sample was cut out from this molded article, and the sample was measured at 40 ° C. (upper / lower temperature difference of 24 ° C.) using a steady-state thermal conductivity measuring device (“GH-1” manufactured by ULVAC-RIKO). The thermal conductivity (W / mK) in the thickness direction was measured.

(3) Anisotropy of thermal conductivity The pellet-shaped resin composition was vacuum dried under the conditions shown in Table 1, and then injection molded under the molding conditions shown in Table 1 to obtain a molded product having a thickness of 2 mm. A 25 mm × 25 mm × 2 mm sample was cut out from this molded article, and the sample was measured at 40 ° C. (upper / lower temperature difference of 24 ° C.) using a steady-state thermal conductivity measuring device (“GH-1” manufactured by ULVAC-RIKO). The thermal conductivity (W / mK) in the thickness direction was measured.

From the thermal conductivity (W / mK) in the thickness direction of this injection-molded product and the thermal conductivity (W / mK) in the thickness direction of the press-molded product measured in (2) above, the following formula:
Thermal conductivity anisotropy = (thermal conductivity in the thickness direction of the injection molded product) / (in the above (2)
(Measured thermal conductivity in the thickness direction of the press-formed product)
Thus, the anisotropy of thermal conductivity was obtained. In the press-formed product, there is almost no difference in the thermal conductivity between the thickness direction and the direction perpendicular thereto. Therefore, it can be said that the closer the ratio of thermal conductivity is to 1, the smaller the orientation of the conductive nanofiller in the flow direction during injection molding is, and the smaller the anisotropy is.

(4) Y / X value After the pellet-shaped resin composition was vacuum dried under the conditions shown in Table 1, press molding was performed under the molding conditions shown in Table 1 to obtain a molded product having a thickness of 2 mm. A sample of 40 mm × 5 mm × 2 mm is cut out from this molded product, and an arbitrary portion of the central portion (portion in the range of 0.8 to 1.2 mm from the surface) of the frozen fracture surface at the center of this sample is scanned. Images were taken using a scanning electron microscope (SEM) and developed on photographic paper having a uniform thickness. In the obtained SEM photograph, the range of 90 μm × 90 μm was arbitrarily extracted at five locations in the size of the molded product. After measuring the mass of the photograph of the extracted range, cut out the portion corresponding to the dispersed phase formed by the high affinity resin (B _aff ) from the extraction range, measure the mass of the photograph of the cut portion, The mass ratio (% by mass) of the photograph of the portion corresponding to the dispersed phase with respect to the extraction range was calculated. The mass ratio of this photograph can be regarded as the volume ratio (volume%) of the dispersed phase with respect to the resin composition in the extraction range because the thickness of the photographic paper used is uniform. In the following Examples and Comparative Examples, the volume ratio of the dispersed phase was determined for any of the five extracted locations, and the average value was defined as the ratio X (unit: volume%) of the dispersed phase with respect to the entire resin composition. .

Further, SEM photography was performed in the same manner as described above, and arbitrary five locations (each in the range of 90 μm × 90 μm in size of the molded product) were extracted from the obtained SEM photograph. All the portions corresponding to the conductive nanofiller (A) were cut out from the photograph of the extracted range, and the total mass of the cut portion of the photograph was measured. Moreover, the mass of the photograph of the part corresponding to the conductive nanofiller (A _dsp ) contained in the dispersed phase among the part corresponding to the conductive nanofiller (A) is measured, and the total conductivity of the extraction range is measured. The mass ratio (mass%) of the photograph of the conductive nanofiller (A _dsp ) in the dispersed phase relative to the conductive nanofiller (A) was calculated. In this case as well, the mass ratio of the photograph is regarded as the volume ratio (capacity%) of the conductive nanofiller (A _dsp ) in the dispersed phase with respect to the total conductive nanofiller (A) in the extraction range. In the following examples and comparative examples, the volume fraction of the conductive nanofiller (A _dsp ) in the dispersed phase was determined for any of the five extracted locations, and the average value was calculated as the value in the resin composition. The ratio Y (unit: volume%) of the conductive nanofiller (A _dsp ) in the dispersed phase relative to the total conductive nanofiller (A) was used.

  The Y / X value was determined from the X and Y values thus calculated.

Moreover, the electroconductive nano filler (A), resin (B), functional group containing compound (C), and filler (D) which were used in the Example and the comparative example are shown below. In addition, the G / D value of the following conductive nanofiller (A) is measured at an excitation laser wavelength of 532 nm using a laser Raman spectroscopy system [“NRS-3300” manufactured by JASCO Corporation], and is about 1585 cm ^−1. It was determined from the peak intensity of the Raman spectrum of the G band observed in the vicinity and the D band observed in the vicinity of about 1350 cm ⁻¹ .

(A) Conductive nanofiller:
-Conductive nanofiller (a-1)
Multi-walled carbon nanotube (“MWNT-7” manufactured by Nanocarbon Technologies, Inc., diameter distribution 40 to 90 nm, aspect ratio 100 or more, G / D value 8.0).
-Conductive nanofiller (a-2)
Carbon nanofiber (“VGCF” manufactured by Showa Denko KK, average diameter 150 nm, aspect ratio 60, G / D value 9.6).

(B _aff ) Resin having high affinity with conductive nanofiller (A):
・ Resin (b _aff -1)
Polyamide (Nylon 6 “1022B” manufactured by Ube Industries, Ltd.).
・ Resin (b _aff -2)
Polyamide (Nylon 6 “1011FB” manufactured by Ube Industries, Ltd.).
・ Resin (b _aff -3)
Polyamide (Aromatic polyamide “Nylon-MXD6 S6121” manufactured by Mitsubishi Gas Chemical Company, Inc.).
・ Resin (b _aff -4)
Polyethylene (Asahi Kasei Chemicals Corporation high density polyethylene "Sunfine LH-411", melt flow rate measured in accordance with JIS K6922-1 8g / 10min).
・ Resin (b _aff -5)
Polyphenylene sulfide (“Fortron W202A” manufactured by Kureha Corporation, linear polyphenylene sulfide having a melt viscosity of 20 Pa · s at a temperature of 310 ° C. and a shear rate of 1200 sec− ¹ ).

(B1) Other resins:
・ Resin (b1-1)
Polyphenylene sulfide (“Fortron W202A” manufactured by Kureha Corporation, linear polyphenylene sulfide having a melt viscosity of 20 Pa · s at a temperature of 310 ° C. and a shear rate of 1200 sec− ¹ ).
・ Resin (b1-2)
Polybutylene terephthalate ("DURANEX 2000" manufactured by Wintech Polymer Co., Ltd.).
・ Resin (b1-3)
Polycarbonate ("Iupilon S2000" manufactured by Mitsubishi Engineering Plastics Co., Ltd.).
・ Resin (b1-4)
Polyamide (Nylon 6 “1022B” manufactured by Ube Industries, Ltd.).
・ Resin (b1-5)
Polyamide (Nylon 6 “1011FB” manufactured by Ube Industries, Ltd.).

In addition, the order of the affinity (high-low order) of the high affinity resin (B _aff ) and the resin (B1) used in the examples and comparative examples with respect to the carbon-based nanofiller is as follows:
(B _aff -4)> (b _aff -3) ≥ (b _aff -5) (= (b1-1))>(b1-2)> (b _aff -1) (= (b1-4)) = (B _aff -2) (= (b1-5))> (b1-3)
It is.

(C) Functional group-containing compound / functional group-containing compound (c-1)
3-glycidyloxypropyltrimethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.).
-Functional group-containing compound (c-2)
3- (Triethoxysilyl) propyl isocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.).
-Functional group-containing compound (c-3)
Epoxy modified polyethylene (Sumitomo Chemical Co., Ltd. “Bond First-E”, glycidyl methacrylate content 12 mass%).
(D) Filler / insulating thermal conductive filler (d-1)
Spherical boron nitride (“FS-3” manufactured by Mizushima Alloy Iron Co., Ltd.).

Example 1
1% by volume of conductive nanofiller (a-1), 21% by volume of resin (b _aff -5), 77.5% by volume of resin (b1-4) and functional group content with respect to a total of 100% by volume of all components Compound (c-1) 0.5% by volume is added to a biaxial melt kneading extruder equipped with a vent (manufactured by Technobel, screw diameter: 15 mm, L / D: 60), and cylinder setting Melt kneading was performed under the conditions of a temperature of 290 ° C. and a screw rotation speed of 100 rpm. The discharged kneaded material was extruded into a strand shape, cooled, and then cut with a strand cutter to obtain a pellet-shaped resin composition. About this resin composition, Y / X value, volume resistivity, thermal conductivity, and its anisotropy were measured according to the said method. The results are shown in Table 2.

(Example 2)
A twin-screw melt-kneading extruder containing 4.55% by volume of conductive nanofiller (a-1) and 95.45% by volume of resin (b _aff -3) and equipped with a vent (manufactured by Technobel, screw diameter) : 15 mm, L / D: 60), and melt kneading was performed under the conditions of a cylinder set temperature of 270 ° C. and a screw rotation speed of 100 rpm. The discharged kneaded material was extruded into a strand shape, cooled, and then cut with a strand cutter to produce pellets. After the pellets were vacuum dried at 80 ° C. for 15 hours, 22% by volume of the pellets (1% by volume of the conductive nanofiller (a-1) and 100% by volume of all the components of the target resin composition and Resin (b _aff- 3) consisting of 21% by volume), resin (b1-1) 77.4% by volume and functional group-containing compound (c-1) 0.6% by volume in the biaxial melt kneading extruder. The mixture was melted and kneaded under the conditions of a cylinder set temperature of 290 ° C. and a screw rotation speed of 100 rpm. The discharged kneaded material was extruded into a strand shape, cooled, and then cut with a strand cutter to obtain a pellet-shaped resin composition. About this resin composition, Y / X value, volume resistivity, thermal conductivity, and its anisotropy were measured according to the said method. The results are shown in Table 2.

(Example 3)
The compounding amount of the conductive nanofiller (a-1) is changed to 8.7% by volume, and 91.3% by volume of the resin ( _baff- 4) is used instead of the resin ( _baff- 3), and the cylinder set temperature Pellets were produced in the same manner as in Example 2 except that was changed to 200 ° C. After the pellets were vacuum dried at 80 ° C. for 15 hours, 23% by volume of the pellets (2% by volume of the conductive nanofiller (a-1) and 100% by volume of the total components of the target resin composition and Resin (b _aff- 4) consisting of 21% by volume), resin (b1-2) 70% by volume and functional group-containing compound (c-3) 7% by volume, except that the cylinder set temperature was changed to 260 ° C. Obtained a pellet-shaped resin composition in the same manner as in Example 2. About this resin composition, Y / X value, volume resistivity, thermal conductivity, and its anisotropy were measured according to the said method. The results are shown in Table 2.

Example 4
Except for using 12.5% by volume of conductive nanofiller (a-2) instead of conductive nanofiller (a-1) and changing the blending amount of resin (b _aff -1) to 87.5% by volume. Pellets were produced in the same manner as in Example 2. After the pellets were vacuum dried at 80 ° C. for 15 hours, 24% by volume of the pellets (3% by volume of the conductive nanofiller (a-2) and 100% by volume of the total components of the target resin composition and Resin (comprising 21% by volume of resin (b _aff -1)), 75.5% by volume of resin (b1-3) and 0.5% by volume of functional group-containing compound (c-1), and a cylinder set temperature of 280 ° C A pellet-shaped resin composition was obtained in the same manner as in Example 2 except that the above was changed. About this resin composition, Y / X value, volume resistivity, thermal conductivity, and its anisotropy were measured according to the said method. The results are shown in Table 2.

(Example 5)
Pellets were produced in the same manner as in Example 2 except that 95.45% by volume of resin (b _aff -5) was used instead of resin (b _aff -3) and the cylinder set temperature was changed to 290 ° C. After the pellets were vacuum-dried at 130 ° C. for 6 hours, 22% by volume of the pellets (1% by volume of the conductive nanofiller (a-1) and 100% by volume of the total components of the target resin composition and Resin (comprising 21% by volume of resin (b _aff -5)), 77.5% by volume of resin (b1-4) and 0.5% by volume of functional group-containing compound (c-1), and a cylinder set temperature of 240 ° C. A pellet-shaped resin composition was obtained in the same manner as in Example 2 except that the above was changed. About this resin composition, Y / X value, volume resistivity, thermal conductivity, and its anisotropy were measured according to the said method. The results are shown in Table 2.

(Comparative Examples 1-9)
A pellet-shaped resin composition was prepared in the same manner as in Example 1 except that conductive nanofillers, high-affinity resins, other resins, functional group-containing compounds and fillers were used in the combinations and blending amounts shown in Table 2. Obtained. In Comparative Example 5, the cylinder set temperature was changed to 260 ° C., and in Comparative Examples 6 to 7, the cylinder set temperature was changed to 280 ° C. About these resin compositions, Y / X value, volume resistivity, thermal conductivity, and the anisotropy were measured according to the said method. The results are shown in Table 2.

(Comparative Example 10)
For the resin (b1-1), the volume resistivity, the thermal conductivity, and the anisotropy thereof were measured according to the aforementioned methods. The results are shown in Table 2.

(Comparative Example 11)
With respect to the resin (b _aff -1), the volume resistivity, thermal conductivity, and anisotropy thereof were measured according to the above methods. The results are shown in Table 2.

(Comparative Examples 12-14)
A pellet-shaped resin composition was obtained in the same manner as in Example 1 except that conductive nanofillers, high-affinity resins, other resins, and functional group-containing compounds were used in the combinations and blending amounts shown in Table 2. About these resin compositions, Y / X value, volume resistivity, thermal conductivity, and the anisotropy were measured according to the said method. The results are shown in Table 2.

As is clear from the results shown in Table 2, the resin compositions (Examples 1 to 5) of the present invention are composed of the conductive nanofiller (A), the high affinity resin (B _aff ), Resin compositions not containing at least one component of resin (B1) and functional group-containing compound (C) (Comparative Examples 1 to 9) and resin compositions in which high-affinity resins (B _aff ) do not form a dispersed phase ( Compared with Comparative Examples 12 to 14), the thermal conductivity and the insulation were combined at a high level, and even when injection molding was performed, the thermal conductivity anisotropy was hardly exhibited.

Specifically, when Comparative Example 8 and Comparative Example 10 are compared, thermal conductivity, insulating properties, and high-affinity resin (B _aff ) and functional group-containing compound (C) are added to resin (B1). It was found that the thermal conductivity anisotropy hardly changed. On the other hand, when Comparative Examples 3 to 4 and Comparative Example 10 are compared, the thermal conductivity is improved by adding the conductive nanofiller (A) to the resin (B1), but the insulating property is decreased and the thermal conductivity is reduced. It was found that the anisotropy of was increased.

Further, when Comparative Examples 1 and 7 and Comparative Examples 3 and 6 are compared, the heat conductivity is improved by adding the high affinity resin (B _aff ), but the heat generated by the addition of the conductive nanofiller (A). The increase in conductivity anisotropy could not be sufficiently suppressed, and it was difficult to suppress the decrease in insulation. Further, when Comparative Example 2 and Comparative Example 3 are compared, although the thermal conductivity is improved by adding the functional group-containing compound (C), the difference in thermal conductivity due to the addition of the conductive nanofiller (A). The increase in the directivity cannot be sufficiently suppressed, and it is difficult to suppress the decrease in the insulating properties.

  Furthermore, when Comparative Example 3, Comparative Example 9 and Comparative Example 10 are compared, when the conductive nanofiller (A) and the insulating heat conductive filler (d-1) are used in combination, only the conductive nanofiller (A) is obtained. Compared with the case where it is used, the thermal conductivity is further improved and the decrease in insulation due to the addition of the conductive nanofiller (A) is suppressed, but the increase in the anisotropy of the thermal conductivity cannot be sufficiently suppressed. It was.

In contrast, the conductive nanofiller (A), the high affinity resin (B _aff ), and the functional group-containing compound (C) are added to the resin (B1), and the dispersed phase is added by the high affinity resin (B _aff ). When the continuous phase is formed from the resin (B1) (Example 1), Y is 65% by volume, Y / X is 3.1, and the insulating property of the resin (B1) is maintained at a high level. As compared with Comparative Examples 1 to 3, it was confirmed that the thermal conductivity can be improved and the increase in the anisotropy of the thermal conductivity can be sufficiently suppressed.

On the other hand, even when the conductive nanofiller (A), the high affinity resin (B _aff ) and the functional group-containing compound (C) are added to the resin (B1), the dispersed phase is changed by the resin (B1). When a continuous phase is formed by (B _aff ) (Comparative Examples 12 to 14), compared with Comparative Examples 1 to 3, the thermal conductivity can be improved and the increase in anisotropy of thermal conductivity can be suppressed. However, it has been found that the insulation properties are significantly reduced.

Moreover, when Example 2-5 is compared with Example 1, after mixing a conductive nano filler (A) and high affinity resin ( _Baff ), resin (B1) and a functional group containing compound are added to this mixture. By mixing (C), it was confirmed that the thermal conductivity and insulation were further improved, and that the thermal conductivity anisotropy was less likely to be exhibited even in processing under shear. This is because the conductive nanofiller (A) and the high-affinity resin (B _aff ) are mixed in advance so that the conductive nano-filler (A) is _contained in the dispersed phase formed by the high-affinity resin (B _aff ). It is presumed that this is because a large amount of is taken in and the uneven distribution of the conductive nanofiller (A) in the dispersed phase in the resin composition of the present invention increases.

  As described above, according to the present invention, there is obtained a resin composition that has both high thermal conductivity and insulating properties, and that hardly exhibits anisotropy of thermal conductivity even in processing under shear. It becomes possible.

  Therefore, the resin composition of the present invention is used in applications that require thermal conductivity, heat dissipation, isotropic thermal conductivity, insulation, etc., for example, various parts for automobiles, various parts for electric / electronic devices, high heat It is useful for applications such as conductive sheets, heat sinks, and electromagnetic wave absorbers.

1: conductive nanofiller (A), 2: functional group-containing compound (C), 3: dispersed phase [mainly resin (B _aff )], 4: continuous phase [mainly resin (B1)].

Claims (6)

It is a resin composition containing a conductive nanofiller (A), two or more kinds of resins (B), and a compound (C) having a functional group,
The resin composition includes a dispersed phase formed of a resin (B _aff ) having the highest affinity with the conductive nanofiller (A) of the two or more types of resins (B), and the remaining one or more types. A continuous phase formed of the resin (B1)
In the dispersed phase, the conductive nanofiller (A) exists,
The ratio of the dispersed phase to the entire resin composition is X (unit: volume%), and the ratio of the conductive nanofiller (A _dsp ) contained in the dispersed phase to the total conductive nanofiller (A) is Y ( Unit: volume%), Y is 20 volume% or more, and Y / X is 1.2 or more. 2. The resin according to claim 1, wherein the content of the resin (B _aff ) having the highest affinity with the conductive nanofiller (A) is 70% by volume or less based on the entire resin composition. Composition.   The resin composition according to claim 1, wherein the conductive nanofiller (A) is a carbon-based nanofiller.   The functional group of the compound (C) consists of an alkoxysilyl group, a silanol group, an epoxy group, an isocyanate group, an amino group, a hydroxyl group, a mercapto group, a ureido group, a carboxyl group, a carboxylic anhydride group, an oxetane group and an oxazoline group. The resin composition according to any one of claims 1 to 3, wherein the resin composition is at least one group selected from the group. The resin composition according to claim 1, wherein the thermal conductivity is 0.3 W / mK or more and the volume resistivity is 10 ¹³ Ω · cm or more. A method for producing a resin composition comprising a conductive nanofiller (A), two or more kinds of resins (B), and a compound (C) having a functional group,
At least part of the conductive nanofiller (A) and at least part of the resin (B _aff ) having the highest affinity with the conductive nanofiller (A) of the two or more kinds of resins (B); To prepare a mixture of the conductive nanofiller (A) and the resin (B _aff ),
Production of a resin composition comprising mixing the mixture, one or more remaining resins (B1) of the two or more resins (B), and a compound (C) having a functional group. Method.

Images