JP2012067208A - Polycarbonate-based resin composition and molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a material developable of high conductivity and good moldability, while reducing a conductive material contained in a polycarbonate-based resin.SOLUTION: The polycarbonate-based resin composition containing a polycarbonate-based resin (A) and a styrene-based resin (master batch) (B) containing carbon nanotubes, wherein the styrene-based resin (B) is obtained by highly dispersing carbon nanotubes in a monomer stage and polymerizing, and the molding obtained by using the resin composition are provided, and thereby the material developable of good moldability and high conductivity with a small amount content of the conductive material is provided.

Description

  The present invention relates to a polycarbonate resin composition containing a polycarbonate resin and a carbon nanotube-containing styrene resin, and a molded article formed by molding the resin composition.

  Polycarbonate resins have high heat resistance, excellent mechanical properties and optical properties (transparency), but are less expensive than physical properties, so they are widely used in transportation equipment such as aircraft and automobiles, electrical and electronic, optical, and medical equipment. It is used. Under such circumstances, it is common to achieve high functionality by adding an additive to a polycarbonate resin. For example, a resin imparted with conductivity by mixing a polycarbonate resin and a conductive material. It has also been reported that it can be used as a composition (for example, see Patent Document 1). Recently, carbon nanotubes, which have been remarkably developed, have been used as conductive materials, and attempts have been made to improve the conductivity of molded products and reduce the detachment of conductive materials by adding a small amount. However, the dispersion of carbon nanotubes is insufficient. However, sufficient effects for satisfying both of the above improvements have not been given. (For example, see Patent Document 2)

JP-A-4-342758 JP 2006-97006 A

  In view of the above circumstances, the problem to be solved by the present invention is to provide a material capable of reducing the conductive material contained in the polycarbonate resin and exhibiting high conductivity and good moldability.

  As a result of intensive studies to solve the above problems, the present inventors have polymerized a hard-dispersed carbon nanotube by mechanically dispersing it in a monomer mixture containing a styrene monomer (masterbatch), and polycarbonate. The present invention has been completed by finding that high-conductivity is expressed with a good molding property and a small amount of conductive material by heat-melting and mechanically dispersing and molding the base resin and the masterbatch.

  That is, the present invention is a resin composition containing a polycarbonate resin (A) and a styrene resin (master batch) (B) containing carbon nanotubes, wherein the styrene resin (B) contains carbon nanotubes. The present invention provides a polycarbonate resin composition characterized by being highly dispersed in a monomer stage and polymerized, and a molded product obtained using the same.

  The polycarbonate-type resin composition of this invention is excellent in electroconductivity, and can reduce the addition amount of an electroconductive material. Therefore, it is excellent in reduction of conductive material detachment and processability, and has good mold reproducibility even when a molded body is obtained by injection molding, etc., especially for electrical and electronic parts that are downsized with higher integration. It can be used suitably. In addition, even when flame retardants and other additives are used in combination, the ratio of use can be reduced because of its excellent uniform dispersibility, and it is an environment-friendly molded product that can be recovered and recycled. Is also suitable.

The present invention is described in detail below.
[Polycarbonate resin (A)]
The polycarbonate resin (hereinafter abbreviated as PC resin) (A) used in the present invention is obtained by reacting a dihydric phenol with a carbonate precursor. Examples of the reaction method include an interfacial polymerization method, a melt transesterification method, a solid phase transesterification method of a carbonate prepolymer, and a ring-opening polymerization method of a cyclic carbonate compound.

  Representative examples of the dihydric phenol used above include hydroquinone, resorcinol, 4,4′-biphenol, 1,1-bis (4-hydroxyphenyl) ethane, and 2,2-bis (4-hydroxyphenyl). Propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane (generic name: bisphenol A), 2,2-bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 2,2-bis ( 4-hydroxyphenyl) pentane, 4,4 ′-(p-phenylenediisopropylidene) diphenol, 1,1-bis (4-hydroxyphene) L) -4-isopropylcyclohexane, bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) sulfone, bis (4- Hydroxyphenyl) ketone, bis (4-hydroxyphenyl) ester, bis (4-hydroxy-3-methylphenyl) sulfide, 9,9-bis (4-hydroxyphenyl) fluorene and 9,9-bis (4-hydroxy-) 3-methylphenyl) fluorene and the like. A particularly preferred dihydric phenol is bis (4-hydroxyphenyl) alkane. Among them, bisphenol A is preferable because it is excellent in toughness and deformation characteristics, and is widely used.

  In the present invention, in addition to the bisphenol A-based polycarbonate, which is a general-purpose PC resin, it is also possible to use a special PC resin manufactured using other dihydric phenols.

  For example, as part or all of the dihydric phenol component, 4,4 ′-(m-phenylenediisopropylidene) diphenol, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-Hydroxyphenyl) -3,3,5-trimethylcyclohexane, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenylfluorene) was used. Polycarbonate is suitable for applications where dimensional changes due to water absorption and strict shape stability are required. These dihydric phenols other than bisphenol A are preferably used in an amount of 5 mol% or more, particularly 10 mol% or more of the entire dihydric phenol component constituting the polycarbonate.

In addition, when high rigidity and good hydrolysis resistance are required, it is particularly preferable that the configuration of the PC resin is a copolymerized PC resin of the following (1) to (3).
(1) In 100 mol% of the dihydric phenol component constituting the polycarbonate component, 4,4 '-(m-phenylenediisopyridene) diphenol component is 20 to 80 mol%, and 9,9-bis (4- Copolymer polycarbonate in which the hydroxy-3-methylphenyl) fluorene component is 20 to 80 mol% (2) In 100 mol% of the dihydric phenol component constituting the polycarbonate component, the bisphenol A component is 10 to 95 mol%, Copolymerized polycarbonate in which the bis (4-hydroxy-3-methylphenyl) fluorene component is 5 to 90 mol% (3) In 100 mol% of the dihydric phenol component constituting the polycarbonate component, 4,4 ′-(m-phenylenediene (Isopyridene) diphenol component is 20 to 80 mol%, - bis (4-hydroxyphenyl) -3,3,5 copolycarbonate hexane component is 20 to 80 mol% trimethyl cyclo

  These special PC resins may be used alone or in combination of two or more. It is also possible to mix with bisphenol A type polycarbonate.

  The manufacturing method and characteristics of these special PC resins are described in detail in, for example, JP-A-6-172508, JP-A-8-27370, JP-A-2001-55435, and JP-A-2002-117580. Yes.

Of the various PC resins described above, those having a water absorption and glass transition temperature (Tg) within the following ranges by adjusting the copolymer composition and the like have good hydrolysis resistance of the polymer itself. In addition, since it is remarkably excellent in low warpage after molding, it is particularly suitable in a field where form stability is required.
(1) a PC resin having a water absorption of 0.05 to 0.15%, preferably 0.06 to 0.13% and a Tg of 120 to 180 ° C., or
(2) PC resin having a Tg of 160 to 250 ° C., preferably 170 to 230 ° C., and a water absorption of 0.10 to 0.30%, preferably 0.13 to 0.30%.

  Here, the water absorption rate of the PC resin was measured using a disc-shaped test piece having a diameter of 45 mm and a thickness of 3.0 mm, after being immersed in water at 23 ° C. for 24 hours in accordance with ISO-62-1980. It is the value. Moreover, Tg is a value calculated | required by the differential scanning calorimeter measurement based on JISK7121.

  As the carbonate precursor, carbonyl halide, carbonic acid diester, haloformate, or the like is used, and specific examples include phosgene, diphenyl carbonate, dihaloformate of dihydric phenol, and the like.

  In producing a polycarbonate resin by interfacial polymerization using the above dihydric phenol and carbonate precursor, a catalyst, a terminal terminator, an antioxidant for preventing the dihydric phenol from being oxidized, etc. are used as necessary. May be. The polycarbonate resin of the present invention includes a branched carbonate resin obtained by copolymerizing a trifunctional or higher polyfunctional aromatic compound.

  The branched PC resin increases the melt tension of the resin composition of the present invention, and can improve molding processability in extrusion molding, foam molding and blow molding based on such characteristics. As a result, a molded product by these molding methods having excellent dimensional accuracy can be obtained.

  Examples of the trifunctional or higher functional aromatic compound used in the branched PC resin include 4,6-dimethyl2,4,6-tris (4-hydroxydiphenyl) heptene-2,2,4,6-trimethyl. -2,4,6-tris (4-hydroxyphenyl) heptane, 1,3,5-tris (4-hydroxyphenyl) benzene, 1,1,1-tris (4-hydroxyphenyl) ethane, 1,1, 1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane, 2,6-bis (2-hydroxy-5-methylbenzyl) -4-methylphenyl, and 4- {4- [1,1-bis ( Preferred examples include trisphenol such as 4-hydroxyphenyl) ethyl] benzene} -α, α-dimethylbenzylphenol. Other polyfunctional aromatic compounds include phloroglucin, phloroglucide, tetra (4-hydroxyphenyl) methane, bis (2,4-dihydroxyphenyl) ketone, 1,4-bis (4,4dihydroxytriphenylmethyl) benzene. And trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid, and acid chlorides thereof. Of these, 1,1,1-tris (4-hydroxyphenyl) ethane and 1,1,1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane are preferable, and 1,1,1-tris (4- Hydroxyphenyl) ethane is preferred.

  The structural unit derived from the polyfunctional aromatic compound in the branched PC resin is 0.1% in a total of 100 mol% of the structural unit derived from the dihydric phenol and the structural unit derived from the polyfunctional aromatic compound. It is 03-1 mol%, Preferably, it is 0.07-0.7 mol%, Most preferably, it is 0.1-0.4 mol%.

  Further, such a branched structural unit is not only derived from a polyfunctional aromatic compound but also derived without using a polyfunctional aromatic compound, such as a side reaction during a melt transesterification reaction. Also good. Such a branched structure can be calculated by 1H-NMR.

  The aliphatic bifunctional carboxylic acid is preferably α, ω-dicarboxylic acid. Examples of the aliphatic difunctional carboxylic acid include sebacic acid (decanedioic acid), dodecanoic acid, tetradecanedioic acid, octadecanedioic acid, and linear saturated aliphatic dicarboxylic acid such as icosanedioic acid, and cyclohexane. Preferred are alicyclic dicarboxylic acids such as dicarboxylic acids. As the bifunctional alcohol, an alicyclic diol is more preferable, and examples thereof include cyclohexanedimethanol, cyclohexanediol, and tricyclodecane dimethanol.

  Interfacial polymerization method, melt transesterification method, solid phase transesterification method of carbonate prepolymer, and ring-opening polymerization method of cyclic carbonate compound, which are the production methods of the PC resin of the present invention. well known.

The viscosity average molecular weight of the PC resin of the present invention is not particularly limited, but is preferably 1 × 10 ^{4 to} 5 × 10 ⁴ .

If the PC resin has a viscosity average molecular weight greater than 1 × 10 ⁴ , practically sufficient toughness and crack resistance can be obtained, and if it is 5 × 10 ⁴ or less, molding processing at a relatively low temperature is possible. Possible, versatile and preferred.

[Carbon nanotube-containing styrene resin (masterbatch) (B)]
The carbon nanotube-containing styrene resin used in the present invention is a mixture of a monomer mixture containing a styrene monomer, which is a resin raw material, and carbon nanotubes. ) It is obtained by polymerizing a mixed solution in which carbon nanotubes are moderately dispersed in a monomer mixture. At this time, only one kind of styrene monomer may be used as the monomer mixture containing the styrene monomer.

  Examples of the styrenic monomer that can be used in the present invention include the following. Styrene and its derivatives; for example, styrene, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene, alkyl styrene such as octyl styrene, fluorostyrene, chlorostyrene , Halogenated styrene such as bromostyrene, dibromostyrene and iodostyrene, nitrostyrene, acetylstyrene, methoxystyrene and the like.

  Moreover, in the range which does not impair the effect of this invention, it is good also as a monomer mixture by using together the other monomer copolymerizable with a styrene-type monomer. Examples of monomers that can be used in combination include acrylic acid acrylic esters such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, heptyl acrylate, and octyl acrylate, methyl methacrylate, and methacrylic acid. Examples include methacrylic acid acrylic esters such as ethyl, polymerizable unsaturated fatty acids such as methacrylic acid, maleic acid, fumaric acid and itaconic acid, vinylcyan compounds, unsaturated carboxylic acid anhydrides, and amino group-containing unsaturated compounds. Two or more of these may be used at the same time.

[Multi-branched macromonomer]
In addition, a multi-branched macromonomer can be used for easily increasing the molecular weight, increasing the branching, and improving the physical properties.

  As the multibranched macromonomer used in the present invention, a multibranched macromonomer having a plurality of branches and having a plurality of polymerizable double bonds is preferable, and particularly obtained by using a multibranched macromonomer in combination. From the viewpoint of controlling the weight average molecular weight of the multi-branched resin to 10 million or less, the weight average molecular weight (Mw) having a plurality of branches and a plurality of polymerizable double bonds is preferably 1,000 to 15,000, more preferably 2,000 to 8,000 macromonomers.

  Although there is no restriction | limiting in particular as said branched structure, All three bonds except an electron withdrawing group and the bond couple | bonded with this electron withdrawing group are branched by the quaternary carbon atom couple | bonded with the carbon atom. And those in which a branched structure is formed by repeating structural units having an ether bond, an ester bond or an amide bond are preferred.

When the multi-branched resin forms a branched structure with the quaternary carbon, the electron withdrawing group content is 2.5 × 10 ⁻⁴ mmol to 5.0 × / g of the multi-branched resin. It is preferably in the range of 10 ⁻¹ mmol, more preferably in the range of 5.0 × 10 ⁻⁴ mmol to 5.0 × 10 ⁻² mmol.

  It is essential that the multi-branched macromonomer has two or more polymerizable double bonds per molecule. The content of the polymerizable double bond is preferably in the range of 0.1 to 5.5 mmol, and more preferably in the range of 0.5 to 3.5 mmol, per 1 g of the macromonomer. When the amount is less than 0.1 mmol, it is difficult to obtain a high-molecular-weight multi-branched resin. When the amount exceeds 5.5 mmol, the molecular weight of the multi-branched resin tends to increase excessively.

  The multi-branched macromonomer that can be used in the present invention includes a branched structure formed by repeating structural units having an ester bond, an ether bond or an amide bond, and two or more polymerizable double bonds in one molecule at the branch end. And a multi-branched macromonomer having

  A multi-branched macromonomer in which a structural unit having an ester bond is repeated to form a branched structure is a multi-branched polyester polyol in which the carbon atom adjacent to the carbonyl group of the ester bond forming the molecular chain is a quaternary carbon atom. A compound having a polymerizable double bond such as vinyl group or isopropenyl group introduced therein can be mentioned as a preferred embodiment. Introducing a polymerizable double bond into a multi-branched polyester polyol can be carried out by an esterification reaction or an addition reaction.

  In the multi-branched polyester polyol, a substituent may be introduced into a part of the hydroxy group in advance by an ether bond or other bond, and a part of the hydroxy group may be oxidized or other reaction. It may be denatured. Further, in the hyperbranched polyester polyol, a part of the hydroxy group may be esterified in advance.

  As the multi-branched macromonomer, for example, a compound having one or more hydroxy groups is reacted with a monocarboxylic acid having a quaternary carbon atom adjacent to a carboxy group and having two or more hydroxy groups. And a polymer obtained by reacting an unsaturated acid such as acrylic acid or methacrylic acid or an isocyanate group-containing acrylic compound with the hydroxy group which is the terminal group of the polymer. In addition, about the multibranched polymer which formed the branched structure by repeating the structural unit which has an ester bond, "Angew.Chem.Int.Ed.Engl.29" p138-177 (1990) by Mr. Tamalia etc. Are listed.

  Examples of the compound having at least one hydroxy group include a) aliphatic diol, alicyclic diol, or aromatic diol, b) triol, c) tetraol, d) sugar alcohols such as sorbitol and mannitol, e) anne Hydroenenea-heptitol or dipentaerythritol, f) α-alkyl glucoside such as α-methyl glycoside, g) monofunctional alcohol such as ethanol, hexanol, h) alkylene oxide having a weight average molecular weight of at most 8,000, or The hydroxy group containing polymer etc. which were produced | generated by making the derivative and the hydroxyl group in 1 or more types of compounds selected from any of said a) -g) react can be mentioned.

  Examples of the a) aliphatic diol, alicyclic diol and aromatic diol include, for example, 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1, 6-hexanediol, polytetrahydrofuran, dimethylolpropane, neopentylpropane, 2-propyl-2-ethyl-1,3-propanediol, 1,2-propanediol, 1,3-butanediol, diethylene glycol, triethylene glycol , Polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol; cyclohexanedimethanol, 1,3-dioxane-5,5-dimethanol; 1,4-xylylenediethanol, 1-phenyl-1,2-ethanediol Etc. . Examples of the b) triol include trimethylolpropane, trimethylolethane, trimethylolbutane, glycerol, 1,2,5-hexanetriol, 1,3,5-trihydroxybenzene, and the like. Examples of c) tetraol include pentaerythritol, ditrimethylolpropane, diglycerol, and ditrimethylolethane.

  Examples of the monocarboxylic acid in which the carbon atom adjacent to the carboxyl group is a quaternary carbon atom and having two or more hydroxy groups include, for example, dimethylolpropionic acid, α, α-bis (hydroxymethyl) butyric acid, α , Α, α-tris (hydroxymethyl) acetic acid, α, α-bis (hydroxymethyl) valeric acid, α, α-bis (hydroxymethyl) propionic acid, and the like. By using the monocarboxylic acid, the ester decomposition reaction is suppressed and a multibranched polyester polyol can be formed.

  Further, it is preferable to use a catalyst when producing the multi-branched polyester polyol. Examples of the catalyst include organic tins such as dialkyltin oxide, halogenated dialkyltin, dialkyltin biscarboxylate, and stannoxane. Examples thereof include compounds, titanates such as tetrabutyl titanate, organic sulfonic acids such as Lewis acid and p-toluenesulfonic acid.

As a multi-branched macromonomer in which a structural unit having an ether bond is repeatedly formed to form a branched structure, for example, a compound having one or more hydroxy groups is reacted with a cyclic ether compound having one or more hydroxy groups. A branched polymer is then reacted with an unsaturated acid such as acrylic acid or methacrylic acid, an isocyanate group-containing acrylic compound, or a halogenated methylstyrene such as 4-chloromethylstyrene with the hydroxy group that is a terminal group of the polymer. What is obtained is mentioned. Further, as a method for producing the multi-branched polymer, a compound having one or more hydroxy groups, two or more hydroxy groups and a halogen atom, -OSO ₂ OCH ₃ or -OSO ₂ is based on Williamson's ether synthesis method. A method of reacting with a compound containing CH ₃ is also useful.

As the compound having one or more hydroxy groups, any of those mentioned above can be used, and as the cyclic ether compound having one or more hydroxy groups, for example, 3-ethyl-3- (hydroxymethyl) Examples include oxetane, 2,3-epoxy-1-propanol, 2,3-epoxy-1-butanol, and 3,4-epoxy-1-butanol. The compounds having one or more hydroxy groups used in the Williamson ether synthesis method may be those described above, but aromatic compounds having two or more hydroxy groups bonded to an aromatic ring are preferred. Examples of the compound include 1,3,5-trihydroxybenzene, 1,4-xylylenediethanol, 1-phenyl-1,2-ethanediol and the like. Examples of the compound containing two or more hydroxy groups and a halogen atom, —OSO ₂ OCH ₃ or —OSO ₂ CH ₃ include, for example, 5- (bromomethyl) -1,3-dihydroxybenzene, 2-ethyl-2. -(Bromomethyl) -1,3-propanediol, 2-methyl-2- (bromomethyl) -1,3-propanediol, 2- (bromomethyl) -2- (hydroxymethyl) -1,3-propanediol, etc. Can be mentioned. In addition, when manufacturing the said hyperbranched polymer, it is preferable to use a normal catalyst, and examples of the catalyst include BF ₃ diethyl ether, FSO ₃ H, ClSO ₃ H, HClO _{4 and the} like. Can do.

  In addition, examples of the multi-branched macromonomer in which a structural unit having an amide bond is repeatedly formed to form a branched structure include those having a repeating structure having an amide bond via a nitrogen atom in the molecule. 2.0 (PAMAM dentrimer) is a typical one.

〔carbon nanotube〕
The carbon nanotubes used in the present invention have a shape in which one surface of graphite is rolled into a cylindrical shape, and single-walled carbon nanotubes having a structure wound with one layer of the graphite layer are wound with two or more layers. Any of the multi-walled carbon nanotubes may be used.

  The characteristics of the above-mentioned carbon nanotubes are preferably those having 2 to 50 layers of multi-walled carbon nanotubes, particularly those having both the effects of improving the resin properties when blended with a resin. Specifically, Multi-walled carbon nanotubes with a diameter of 20 nm or less are preferred.

  A preferable multi-walled carbon nanotube used in the present invention is one in which 2 to 50 carbon nanotubes are contained in 50% by mass or more in all carbon nanotubes. As the identification method, the number of fibrous nanotubes found in the field of view of a carbon nanotube or a resin composition containing carbon nanotubes observed with a transmission electron microscope of 200,000 times or more is observed. Of these, it is sufficient that the carbon nanotubes having 2 to 50 layers are 50% or more.

  The cylindrical graphite structure that is characteristic of carbon nanotubes can be examined with a high-resolution transmission electron microscope. The graphite layer is preferable so that it can be seen straight and clearly with a transmission microscope, but the graphite layer may be disordered. What disturbs the graphite layer may be defined as carbon nanofiber, and such carbon nanofiber is also included in the carbon nanotube in the present invention.

  The carbon nanotubes used in the present invention can be generally produced by a laser ablation method, arc discharge, thermal CVD method, plasma CVD method, gas phase method, combustion method, etc., but carbon nanotubes produced by any method may be used.

  As a method for dispersing the carbon nanotubes in the resin, it is also preferable to use the carbon nanotubes after being pretreated with a coupling agent. Examples of such coupling agents include isocyanate compounds, organic silane compounds, organic titanate compounds, organic borane compounds, and epoxy compounds.

  The amount of the carbon nanotube used is usually 0. When the total amount is 100 parts by mass in the resin composition containing the polycarbonate resin (A) and the carbon nanotube-containing styrene resin (B). It is 1-10 mass parts, Preferably it is the range of 0.5-3 mass parts.

[Dispersion method of carbon nanotube]
The mechanical dispersion method after mixing the monomer mixture and the carbon nanotube is not particularly limited as long as it is a means capable of fine dispersion in the monomer, but a method capable of fine dispersion in a short time is preferable. . Examples thereof include a high-speed stirring type disperser, a gap shear type mixer (kneader), a roll mill, a ball mill, a sand mill, an ultrasonic homogenizer, a nanomizer, a bead mill, and the like. Particularly, an ultrasonic homogenizer is more preferable in terms of workability.

  In order to perform fine dispersion of the carbon nanotube more efficiently, it is more preferable to use a fine dispersion device and a stirring device in combination. Furthermore, when heat is generated during fine dispersion, it is preferable to provide a cooling device in order to suppress self-radical polymerization by the monomer.

[Polymerization method]
Various widely used polymerization methods of styrene monomers can be applied to the polymerization reaction. The polymerization method is not particularly limited, but bulk polymerization or solution polymerization is preferable.

  In order to reduce the viscosity of the reaction product in the polymerization reaction, an organic solvent may be added to the reaction system. Examples of the organic solvent include toluene, ethylbenzene, xylene, acetonitrile, benzene, chlorobenzene, dichlorobenzene, and anisole. , Cyanobenzene, dimethylformamide, N, N-dimethylacetamide, methyl ethyl ketone and the like. In particular, when it is desired to increase the amount of the hyperbranched macromonomer, it is preferable to use an organic solvent from the viewpoint of suppressing gelation. Thereby, the addition amount of the multibranched macromonomer shown above can be dramatically increased, a large number of branched structures can be introduced, and gelation hardly occurs.

In performing the polymerization reaction, a radical polymerization initiator may be used in order to perform the polymerization efficiently.

  The radical polymerization initiator is not particularly limited. For example, 1,1-bis (t-butylperoxy) cyclohexane, 2,2-bis (t-butylperoxy) butane, 2,2-bis (4 , 4-di-butylperoxycyclohexyl) propane and other peroxyketals, cumene hydroperoxide, hydroperoxides such as t-butyl hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, di Dialkyl peroxides such as -t-hexyl peroxide, diacyl peroxides such as benzoyl peroxide and disinamoyl peroxide, t-butyl peroxybenzoate, di-t-butyl peroxyisophthalate, t-butyl peroxide Pao such as oxyisylpropyl monocarbonate Siesters, N, N′-azobisisobutylnitrile, N, N′-azobis (cyclohexane-1-carbonitrile), N, N′-azobis (2-methylbutyronitrile), N, N′-azobis ( 2,4-dimethylvaleronitrile), N, N′-azobis [2- (hydroxymethyl) propionitrile] and the like, and these can be used alone or in combination.

  Furthermore, a chain transfer agent may be added so that the molecular weight of the obtained carbon nanotube-containing styrene resin does not become excessively large. As the chain transfer agent, either a monofunctional chain transfer agent having one chain transfer group or a polyfunctional chain transfer agent having a plurality of chain transfer groups can be used. Examples of the monofunctional chain transfer agent include alkyl mercaptans and thioglycolic acid esters. Polyfunctional chain transfer agents include ethylene glycol, neopentyl glycol, trimethylol propane, pentaerythritol, dipentaerythritol, tripentaerythritol, sorbitol and the like, the hydroxy group in thioglycolic acid or 3-mercaptopropionic acid And the like esterified with.

[Polymerization method using hyperbranched macromonomer]
By copolymerizing the multi-branched macromonomer, the styrene monomer, and other monomers used in combination as necessary, a multi-branched resin and a linear product that is simultaneously generated depending on the polymerization conditions A resin mixture that is a mixture of the resin and the low-branched resin is obtained. At this time, the above-mentioned hyperbranched macromonomer is preferably used in a ratio of 50 ppm to 1%, more preferably 100 ppm to 2000 ppm (mass basis) with respect to the styrene monomer, thereby The carbon nanotube-containing styrenic resin (B) used in the present invention can be efficiently obtained while being easily generated and easily suppressing gelation.

[Glass fiber]
The polycarbonate-based resin composition of the present invention (hereinafter referred to as PC resin composition) may be used for reinforcing the strength, and glass fibers may be added for the purpose of improving conductivity by improving the dispersibility of carbon nanotubes. Is possible. Although it does not specifically limit as a kind of glass fiber, A thing with an average fiber type of 5 micrometers-30 micrometers is preferable. The addition amount is preferably 5 to 50 parts by mass, more preferably 100 parts by mass when the entire resin composition containing the polycarbonate resin (A) and the carbon nanotube-containing styrene resin (B) is 100 parts by mass. Is 10-40 parts by mass. If the amount is less than 5 parts by mass, the effect of adding glass fiber is small.

[Other additives]
In the PC resin composition of the present invention, auxiliary agents such as stearic acid, sodium stearate, barium stearate, magnesium stearate, liquid paraffin, olefin wax, stearyl amide compound and the like are provided so long as the object of the present invention is not impaired. It can also be used together. Moreover, you may mix | blend various additives as needed. Examples of such additives include flame retardants, antioxidants, heat stabilizers, light stabilizers, ultraviolet absorbers, antistatic agents, lubricants, antiblocking agents, pigments, dyes, crosslinking agents, crosslinking aids, and foaming agents. And inorganic substances such as silica, talc, wollastonite, calcium silicate, kaolin, mica, clay, zinc oxide, calcium carbonate, and glass fiber.

  Furthermore, other resins can be appropriately blended with the PC resin composition of the present invention as long as the effects of the present invention are not impaired. Examples of other resins include rubber-containing polystyrene (HIPS), styrene-butadiene copolymer, styrene-acrylic resin, and styrene-methacrylic resin. Moreover, flexibility is imparted to the resulting molded body by blending the styrene elastomer. Styrenic elastomers are highly compatible with polycarbonate resins and have been selected as low dielectric constant and low dielectric loss tangent elastomers. The styrene elastomer is a styrene-polyolefin copolymer, and has a styrene ratio of 50% or more, more preferably 50 to 80% by mass ratio. As the polyolefin phase, one or more styrenic elastomers such as poly (polyethylene-propylene), polyethylene-polybutylene random copolymer, polybutadiene, and polyisoprene can be used.

[Molecular weight of carbon nanotube-containing styrene resin (B)]
The carbon nanotube-containing styrenic resin (B) used in the present invention has a molding processability when mixed with a PC resin (A) to form a composition, heat resistance, mechanical strength, oil resistance, and the like of the resulting molded product. The weight average molecular weight determined from RI-GPC in the balance is essential 150,000 to 400,000, more preferably 200,000 to 350,000. If the weight average molecular weight is less than 150,000, the strength tends to decrease, and molding defects tend to occur. If it is larger than 400,000, the fluidity of the resin is lowered, and distortion occurs at a low temperature, so that it is difficult to mold into the desired shape.

[Mixing of PC resin (A) and carbon nanotube-containing styrene resin (B)]
The PC resin composition of the present invention only needs to be a mixture of the above-mentioned PC resin (A) and the carbon nanotube-containing styrene resin (B), and the mixing ratio of the molded article to be obtained is desired. It is appropriately selected depending on the physical properties according to the application field. Since the carbon nanotube-containing styrene resin (B) used in the present application is compared with a system in which a general styrene resin and a carbon nanotube are mixed, carbon nanotubes are finely dispersed in the resin in advance. In a scene where a styrenic resin is used for improving the molding processability and conductivity of the PC resin, it is possible to lower the blending ratio and the blending ratio of the carbon nanotubes than the conventional use ratio. For this reason, it does not significantly impair the high heat resistance and flame retardancy inherent to the PC resin (A), and imparts molding processability and conductivity while suppressing deterioration of mechanical strength and oil resistance. It is something that can be done.

  In general applications, the mixing ratio of the PC resin (A) and the carbon nanotube-containing styrene resin (B) is usually 10 to 80 parts by mass of the PC resin (A), and the carbon nanotube-containing styrene resin (B) 20 to 90. It is a mass part, Preferably, it is 20-80 mass parts of PC resin (A), and 20-80 mass parts of carbon nanotube containing styrene resin (B).

[Method for producing molded article]
The PC resin composition of the present invention comprises a PC resin (A), a carbon nanotube-containing styrenic resin (B), and optional glass fibers and the above-mentioned various additives mixed with an ordinary kneading apparatus such as a screw extruder, It can be obtained by melt kneading at a temperature of about 180 to 300 ° C. using a pressure kneader, a Banbury mixer or the like. In the present invention, the resin composition may have a shape that is generally widely used as a feedstock supplied to a molding apparatus for obtaining a molded product according to a specific application. Specifically, for example, a so-called primary molded product such as a plate shape, a rod shape, a cylindrical shape, a conical shape, and a fibrous shape can be used.

  In addition, the PC resin composition of the present invention can be processed by cast extrusion, extrusion molding, injection molding, or the like to produce a molded body having a desired shape. However, the processing method has a good yield. An injection molding method is preferred.

[Injection molding method]
The injection molding method is not limited at all, but it is preferable to use a mold having a multi-point pin gate, a side gate, etc. in that the molten resin composition can be uniformly flowed and molded in a balanced manner. . Further, in order to obtain a molded article having good dimensional accuracy and free from gas haze, a mold provided with a vacuum drawing hole is preferable so that the mold cavity can be decompressed when the molten resin composition is injected. Furthermore, a die having a hot runner is preferable because no scrap is generated and the loss during production is small. When a hot runner is used, a needle valve that closes the gate after completion of the flow of the molten resin composition into the mold cavity is also preferably used so as not to generate a gate mark.

[Use of molded body]
The use of the molded body of the present invention is not limited at all, and is useful as a material for molding various molded products such as home appliance parts, electrical / electronic parts, automobile parts, machine / mechanical parts, cosmetic containers and the like. is there. For example, pipe materials such as hoses and tubes; civil engineering materials such as artificial turf, mats, tunnel sheets, waterproof sheets and roofing; building materials such as furniture, flooring and foam sheets; carpet lining materials, door panel tarpaulins, mud Automotive interior and exterior parts such as gaskets and moldings; Household appliances such as packing and damping sheets; Breaker parts, switch parts, motor parts, ignition coil cases, power plugs, power outlets, coil bobbins, connectors, relay cases, fuse cases, fly It can be suitably used for back transformer parts, focus block parts, distributor caps, harness connectors, IC trays, carrier tapes, clean room partitions, and the like. Furthermore, thinning housings, casings or chassis, such as electronic and electrical products (such as telephones, personal computers, printers, fax machines, copiers, televisions, VCRs, audio equipment and other home appliances / OA equipment, or parts thereof) Useful for housings, casings or chassis. In particular, it is also useful as a printer casing, fixing unit parts, and other machine / mechanical parts of home appliances and OA products such as fax machines that require particularly excellent heat resistance and flame retardancy.

  Hereinafter, the present invention will be described more specifically with reference to examples. The present invention should not be limited to the scope of these examples. Hereinafter, “part” and “%” are based on mass unless otherwise specified.

The measurement method used will be described.
[Carbon nanotube-containing styrene resin (B) GPC measurement conditions for molecular weight]
The molecular weight of the carbon nanotube-containing styrene resin (B) is measured by high performance liquid chromatography (HLC-8220GPC manufactured by Tosoh Corporation), RI detector, TSK gel G6000H × 1 + G5000H × 1 + G4000H × 1 + TSK guard column H × 1, solvent The measurement was performed under the conditions of THF, a flow rate of 1.0 ml / min, and a temperature of 40 ° C. The sample was prepared by dissolving 500 mg of a carbon nanotube-containing styrenic resin in 30 ml of THF, filtering with a filter paper (No. 2) and a 0.5 μm syringe filter, and then diluting the filtrate 10 times with THF.

[Melt Mass Flow Rate Measurement Method]
The measurement was performed according to JIS K7210. Measurement conditions are a temperature of 290 ° C. and a load of 49 N for the PC resin, and a temperature of 200 ° C. and a load of 49 N for the carbon nanotube-containing styrene resin.

[Resin and additives]
As the PC resin (A), Iupilon S-3000F manufactured by Mitsubishi Engineering was used.

As the carbon nanotube, a multiwall carbon nanotube (9.5 nm × 1.5 μm, bulk density 0.06 g / cm ³ ) manufactured by Nanocyl, Belgium was used.

  As glass fiber, CSF-3PE293 manufactured by Nittobo Co., Ltd. was used.

[Molding method]
PC resin (A), carbon nanotube-containing styrenic resin (B) and additives were compounded with a twin screw extruder (280 ° C.), and the compound was hot-pressed at 280 ° C. to obtain a 3 mm thick sheet. It was.

[Measurement of conductivity]
The samples obtained under the above conditions were measured using Mitsubishi Chemical LorBta-EP MCP-T360 (10 ⁶ Ω · cm or less) and Simco ST-3 (10 ⁷ Ω · cm or more).

[About formability]
A sample of the PC resin composition obtained by the compounding was obtained by an injection molding machine (melting temperature 280 ° C.) to obtain a molded product for evaluation (dumbbell piece), and the appearance was judged visually. (Good appearance ○, slightly bad Δ, bad x)

(Preliminary dispersion before polymerization)
The monomer mixture and carbon nanotubes were placed in a 2 L flask and treated in an ice bath for 120 minutes using an ultrasonic homogenizer (output 300 W, Nippon Seiki Seisakusho US-300T) and a stirrer.

[Polymerization equipment / method]
Polymerization was performed using a 3 L SUS304 kettle equipped with a double helical wing and a glass lid with a Riedich cooling pipe.

[Confirmation of polymerization rate]
The reaction polymer was taken out, dissolved in deuterated chloroform, and the filtered sample was confirmed from the decrease in the double bond peak of styrene in ¹ H-NMR.

[Drying method]
The polymerization sample was placed in a box-type vacuum dryer, a trap (dry ice methanol cooling) was connected between the vacuum dryer and the vacuum pump, and the polymerization sample was dried at 80 ° C. and full vacuum for 48 hours.

(Synthesis of carbon nanotube-dispersed styrene resin (B))
Preparation Example 1
50 g of Nanocyl multi-walled carbon nanotubes (9.5 nm × 1.5 μm, bulk density 0.06 g / cm ³ ) and 950 g of styrene monomer were added to the flask and stirred for 5 minutes. Thereafter, the flask was dispersed with an ultrasonic homogenizer (300 w) for 120 minutes while stirring in an ice bath and stirring. The dispersion monomer was charged into a polymerization apparatus, 100 g of ethylbenzene was added, and the mixture was reacted at 138 ° C. for 7 hours. The polymerization rate after the reaction was 98%. The polymer after the reaction was taken out and dried at 80 ° C. under full vacuum for 48 hours to obtain a polymer. The weight average molecular weight of the obtained polymer was 150,000.

Preparation Example 2
In Preparation Example 1, the same procedure was carried out except that 0.5 g of 2,2bis (4,4di, tertiarybutylperoxycyclohexyl) propane was added as a catalyst to the polymerization apparatus, and the polymerization rate after the reaction was 99% of the polymer was obtained. The weight average molecular weight of the obtained polymer was 200,000.

Preparation Example 3
50 g of Nanocyl multi-walled carbon nanotubes (9.5 nm × 1.5 μm, bulk density 0.06 g / cm ³ ) and 950 g of styrene monomer were added to the flask and stirred for 5 minutes. Thereafter, the flask was dispersed with an ultrasonic homogenizer (300 w) for 120 minutes while stirring in an ice bath and stirring. The dispersion monomer was charged into a polymerization apparatus, 50 g of ethylbenzene and 0.3 g of 2,2bis (4,4di, tertiarybutylperoxycyclohexyl) propane as a catalyst were added and reacted at 120 ° C. for 24 hours. The polymerization rate after the reaction was 97%. The polymer after the reaction was taken out and dried at 80 ° C. under full vacuum for 48 hours to obtain a polymer. The weight average molecular weight of the obtained polymer was 400,000.

Reference Example 1 Synthesis of Multibranched Macromonomer (Mm-1) <Synthesis of Multibranched Polyether Polyol 1>
To a 2 liter flask equipped with a stirrer, a thermometer, a dropping funnel and a condenser, 50.5 g of ethoxylated pentaerythritol (5 mol-ethylene oxide-added pentaerythritol) and 1 g of BF ₃ diethyl ether solution (50%) were added at room temperature. Heated to 110 ° C. To this, 450 g of 3-ethyl-3- (hydroxymethyl) oxetane was slowly added over 25 minutes while controlling the exotherm due to the reaction. When the exotherm had subsided, the reaction mixture was further stirred at 120 ° C. for 3 hours and then cooled to room temperature. The resulting multi-branched polyether polyol had a weight average molecular weight of 3,000 and a hydroxyl value of 530.

<Synthesis of Multibranched Polyether 1 Having Methacryloyl Group and Acetyl Group>
In a reactor equipped with a Dean-Stark decanter equipped with a stirrer, a thermometer, a condenser and a gas introduction tube, 50 g of the multi-branched polyether polyol obtained in the above-mentioned <Synthesis of multi-branched polyether polyol 1> .8 g, 150 g of toluene, 0.06 g of hydroquinone and 1 g of paratoluenesulfonic acid, and stirring under normal pressure while blowing 7% oxygen-containing nitrogen (v / v) into the mixed solution at a rate of 3 ml / min. Heated. The amount of heating was adjusted so that the amount of distillate in the decanter was 30 g per hour, and heating was continued until the amount of dehydration reached 2.9 g. After completion of the reaction, the mixture was cooled once, 36 g of acetic anhydride and 5.7 g of sulfamic acid were added, and the mixture was stirred at 60 ° C. for 10 hours. Thereafter, in order to remove the remaining acetic acid and hydroquinone, it was washed with 50 g of 5% aqueous sodium hydroxide solution four times, and further washed once with 50 g of 1% aqueous sulfuric acid solution and twice with 50 g of water. To the obtained organic layer, 0.02 g of methoquinone was added, the solvent was distilled off while introducing 7% oxygen-containing nitrogen (v / v) under reduced pressure, and 60 g of a multibranched polyether having isopropenyl group and acetyl group was obtained. Obtained. The obtained multi-branched polyether had a mass average molecular weight of 3,900, and the introduction rate of isopropenyl group and acetyl group into the multi-branched polyether polyol was 30 mol% and 62 mol%, respectively.

Reference Example 2 Synthesis of Multibranched Macromonomer (Mm-2) <Synthesis of Multibranched Polyether 2 Having Styryl Group and Acetyl Group>
In a reactor equipped with a stirrer, a condenser equipped with a drying tube, a dropping funnel and a thermometer, 50 g of the multibranched polyether polyol obtained in the above-mentioned <Synthesis of multibranched polyether polyol 1>, 100 g of tetrahydrofuran and sodium hydride 4.3 g was added and stirred at room temperature. To this was added dropwise 26.7 g of 4-chloromethylstyrene over 1 hour, and the resulting reaction mixture was further stirred at 50 ° C. for 4 hours. After completion of the reaction, the reaction mixture was once cooled, 34 g of acetic anhydride and 5.4 g of sulfamic acid were added, and the mixture was stirred at 60 ° C. for 10 hours. Thereafter, the tetrahydrofuran was distilled off under reduced pressure, the resulting mixture was dissolved in 150 g of toluene, washed with 50 g of 5% aqueous sodium hydroxide solution to remove the remaining acetic acid, and further 50 g of 1% aqueous sulfuric acid solution. And once with 50 g of water. The solvent was distilled off from the obtained organic layer under reduced pressure to obtain 70 g of a multi-branched polyether having a styryl group and an acetyl group. The obtained multi-branched polyether had a mass average molecular weight of 4,800, and the styryl group and acetyl group introduction rates into the multi-branched polyether polyol were 38 mol% and 57 mol%, respectively.

(Reference Example 3) Synthesis of hyperbranched macromonomer (Mm-3) <Synthesis of hyperbranched macromonomer having a methacryloyl group and an acetyl group>
A four-necked flask was equipped with a stirrer, pressure gauge, condenser and saucer, to which 308.9 g of ethoxylated pentaerythritol and 0.46 g of sulfuric acid were added. Then, it heated to 140 degreeC and 460.5g of 2, 2- di (hydroxymethyl) propionic acid was added over 10 minutes. After 2,2-di (hydroxymethyl) propionic acid is completely dissolved and becomes a transparent solution, the pressure is reduced to 30 to 40 mmHg and the reaction is continued for 4 hours while stirring and the acid value becomes 7.0 mgKOH / g. I let you. Thereafter, 921 g of 2,2-di (hydroxymethyl) propionic acid and 0.92 g of sulfuric acid were added to the reaction solution over 15 minutes to obtain a transparent solution, and then the pressure was reduced to 30 to 40 mmHg, while stirring. The polyester polyol was obtained by reacting for a period of time. In a reaction vessel equipped with a 7% oxygen introduction tube, a thermometer, a Dean-Stark decanter equipped with a condenser, and a stirrer, 10 g of the polyester polyol produced above, 1.25 g of dibutyltin oxide, and 100 g of methyl methacrylate having an isopropenyl group And 0.05 g of hydroquinone were added, and the mixture was heated with stirring while blowing 7% oxygen at a rate of 3 ml / min. The amount of heating is adjusted so that the amount of distillate in the decanter is 15 to 20 g per hour, the distillate in the decanter is taken out every hour, and the corresponding amount of methyl methacrylate is added for 4 hours. Reacted. After completion of the reaction, methyl methacrylate was distilled off under reduced pressure, and 10 g of acetic anhydride and 2 g of sulfamic acid were added to cap the remaining hydroxy groups, followed by stirring at room temperature for 10 hours. After removing sulfamic acid by filtration and distilling off acetic anhydride and acetic acid under reduced pressure, the residue was dissolved in 70 g of ethyl acetate and washed 4 times with 20 g of 5% aqueous sodium hydroxide to remove hydroquinone. Further, it was washed twice with 20 g of a 7% aqueous sulfuric acid solution and twice with 20 g of water. To the obtained organic layer, 0.0045 g of methoquinone was added, and the solvent was distilled off while introducing 7% oxygen under reduced pressure to obtain 11 g of a hyperbranched macromonomer (Mm-3) having an isopropenyl group and an acetyl group. It was. The resulting multi-branched macromonomer (Mm-3) has a weight average molecular weight of 3,000, a number average molecular weight of 2,100, and a double bond introduction amount of 2.00 mmol / g, an isopropenyl group and an acetyl group. The introduction rates were 55 mol% and 36 mol%, respectively.

(Reference Example 4) Synthesis of hyperbranched macromonomer (Mm-4) <Synthesis of PAMAM dendrimer having a styryl group>
To a reactor equipped with a stirrer, a condenser equipped with a drying tube, a dropping funnel and a thermometer, 50 g of a methanol solution (20%) of PAMAM dendrimer (Generation 2.0: manufactured by Dentritech) was added and stirred under reduced pressure. Methanol was distilled off. Subsequently, 50 g of tetrahydrofuran and 3.0 g of finely divided potassium hydroxide were added, and the mixture was stirred at room temperature. 4-chloromethylstyrene 7.0g was dripped at this over 10 minutes, and the obtained reaction mixture was further stirred at 50 degreeC for 3 hours. After completion of the reaction, the mixture was cooled and the solid was filtered, and then tetrahydrofuran was distilled off under reduced pressure to obtain 13 g of a PAMAM dendrimer having a styryl group. The resulting styryl group content of the dendrimer was 2.7 mmol / gram.

Reference Example 5 Synthesis of Multibranched Macromonomer (Mm-5) <Multibranched Polyether Polyol 2 Having Styryl Group and Acetyl Group>
A light-shielding reaction vessel equipped with a stirrer, a condenser, a light-shielding dropping funnel and a thermometer, and capable of nitrogen sealing. Under nitrogen flow, anhydrous 1,3,5-trihydroxybenzene 0.5 g, potassium carbonate 29 g, 18-crown -6 2.7 g and acetone 180 g were added, and a solution composed of 21.7 g of 5- (bromomethyl) -1,3-dihydroxybenzene and 180 g of acetone was added dropwise over 2 hours while stirring. Thereafter, the mixture was heated and refluxed with stirring until 5- (bromomethyl) -1,3-dihydroxybenzene disappeared. Thereafter, 9.0 g of 4-chloromethylstyrene was added, and the mixture was further heated and refluxed with stirring until the disappearance. Thereafter, 4 g of acetic anhydride and 0.6 g of sulfamic acid were added to the reaction mixture, and the mixture was stirred overnight at room temperature. After cooling, the solid in the reaction mixture was removed by filtration, and the solvent was distilled off under reduced pressure. The obtained mixture was dissolved in dichloromethane and washed three times with water, and then the dichloromethane solution was added dropwise to hexane to precipitate a multibranched polyether. This was filtered and dried to obtain 12 g of a multi-branched polyether polyol having a styryl group and an acetyl group. The mass average molecular weight was 3,200, and the styryl group content was 3.5 mmol / gram.

Preparation Example 4
The same operation as in Preparation Example 1 was carried out except that 200 ppm of the macromonomer (Mm-1) of Reference Example 1 was added to the styrene monomer to obtain a polymer having a polymerization rate of 98% after the reaction. The weight average molecular weight of the obtained polymer was 250,000.

Preparation Example 5
The same operation as in Preparation Example 1 was carried out except that 200 ppm of the macromonomer (Mm-2) of Reference Example 2 was added to the styrene monomer to obtain a polymer having a polymerization rate of 98% after the reaction. The weight average molecular weight of the obtained polymer was 260,000.

Preparation Example 6
The same operation as in Preparation Example 1 was carried out except that 200 ppm of the macromonomer (Mm-3) of Reference Example 3 was added to the styrene monomer to obtain a polymer having a polymerization rate of 98% after the reaction. The weight average molecular weight of the obtained polymer was 250,000.

Preparation Example 7
The same operation as in Preparation Example 1 was carried out except that 400 ppm of the macromonomer (Mm-4) of Reference Example 4 was added to the styrene monomer to obtain a polymer having a polymerization rate of 98% after the reaction. The weight average molecular weight of the obtained polymer was 350,000.

Preparation Example 8
The same operation as in Preparation Example 1 was carried out except that 400 ppm of the macromonomer (Mm-5) of Reference Example 5 was added to the styrene monomer to obtain a polymer having a polymerization rate of 98% after the reaction. The weight average molecular weight of the obtained polymer was 350,000.

Example 1
20 parts of the carbon nanotube-containing styrenic resin obtained in Preparation Example 1 and 80 parts of the PC resin were melt-mixed at 280 ° C. using a twin-screw extruder, cut into strands through a steel belt, and repelletized. The re-pelleted sample was subjected to hot press molding under the conditions described above, and the conductivity was measured. As a result, it was 9 × 10 ² Ω · cm.

Example 2
A sample was obtained in the same manner as in Example 1 except that instead of the carbon nanotube-containing styrene resin obtained in Preparation Example 1, it was changed to Preparation Example 2. It was 2 * 10 < ³ > ohm * cm when heat-press-molding on the above-mentioned conditions and measuring electroconductivity.

Example 3
A sample was obtained in the same manner as in Example 1 except that the carbon nanotube-containing styrene resin obtained in Preparation Example 1 was replaced with Preparation Example 3. It was 4 * 10 < ³ > ohm * cm when heat-press-molding on the above-mentioned conditions and measuring electroconductivity.

Example 4
A sample was obtained in the same manner as in Example 1 except that the carbon nanotube-containing styrene resin obtained in Preparation Example 1 was replaced with Preparation Example 4. It was 9 * 10 < ² > ohm * cm when heat-press-molding on the above-mentioned conditions and measuring electroconductivity.

Example 5
A sample was obtained in the same manner as in Example 1 except that the carbon nanotube-containing styrene resin obtained in Preparation Example 1 was replaced with Preparation Example 5. It was 7 * 10 < ² > ohm * cm when heat-press-molding on the above-mentioned conditions and measuring electroconductivity.

Example 6
A sample was obtained in the same manner as in Example 1 except that instead of the carbon nanotube-containing styrene resin obtained in Preparation Example 1, it was changed to Preparation Example 6. It was 9 * 10 < ² > ohm * cm when heat-press-molding on the above-mentioned conditions and measuring electroconductivity.

Example 7
A sample was obtained in the same manner as in Example 1 except that the carbon nanotube-containing styrene resin obtained in Preparation Example 1 was replaced with Preparation Example 7. It was 1 * 10 < ³ > ohm * cm when heat-press-molding on the above-mentioned conditions and measuring electroconductivity.

Example 8
A sample was obtained in the same manner as in Example 1 except that instead of the carbon nanotube-containing styrene resin obtained in Preparation Example 1, it was changed to Preparation Example 8. It was 2 * 10 < ³ > ohm * cm when heat-press-molding on the above-mentioned conditions and measuring electroconductivity.

Comparative Example 1
19 parts of polystyrene having a linear weight average molecular weight of 150,000, 80 parts of PC resin, and 1 part of carbon nanotubes were melt-mixed at 280 ° C. using a twin screw extruder, and strand-cut through a steel belt to be repelletized. The re-pelleted sample was subjected to hot press molding under the above-described conditions, and the conductivity was measured. As a result, it was 3 × 10 ⁴ Ω · cm.

Comparative Example 2
A sample was obtained in the same manner except that polystyrene having a weight average molecular weight of 400,000 was used instead of the polystyrene of Comparative Example 1. It was 6 * 10 < ⁴ > ohm * cm when hot-press-molding on the above-mentioned conditions and measuring electroconductivity.

Comparative Example 3
Instead of the polystyrene of Comparative Example 1, the same procedure was performed except that polystyrene having a weight average molecular weight of 250,000 obtained by introducing 200 ppm of the hyperbranched macromonomer (Mm-1) of Reference Example 1 with respect to the styrene monomer was used. Got a sample. It was 1 × 10 ⁴ Ω · cm when subjected to hot press molding under the above conditions and measured for conductivity.

Comparative Example 4
50 g of Nanocyl multi-walled carbon nanotubes (9.5 nm × 1.5 μm, bulk density 0.06 g / cm ³ ) and 950 g of styrene monomer were added to the flask and stirred for 5 minutes. Thereafter, the flask was dispersed with an ultrasonic homogenizer (300 w) for 120 minutes while stirring in an ice bath and stirring. The dispersion monomer was charged into a polymerization apparatus, 100 g of ethylbenzene was added, and 0.3 g of a polymerization initiator t-butyl peroxybenzoate was reacted at 138 ° C. for 7 hours. The polymerization rate after the reaction was 98%. The polymer after the reaction was taken out and dried at 80 ° C. under full vacuum for 48 hours to obtain a polymer. The weight average molecular weight of the obtained polymer was 100,000. 20 parts of the obtained carbon nanotube-containing styrene resin and 80 parts of PC resin were melt-mixed at 280 ° C. using a twin-screw extruder, and strand-cut through a steel belt to be repelletized. The re-pelleted sample was subjected to hot press molding under the conditions described above, and the conductivity was measured and found to be 1 × 10 ³ Ω · cm.

Example 9
30 parts of the carbon nanotube-containing styrenic resin obtained in Preparation Example 1, 50 parts of PC resin, and 20 parts of glass fiber were melt-mixed at 280 ° C. using a twin screw extruder, and strand-cut through a steel belt to re-pellet. . The re-pelleted sample was subjected to hot press molding under the conditions described above, and the conductivity was measured. As a result, it was 7 × 10 ¹ Ω · cm.

Example 10
20 parts of the carbon nanotube-containing styrenic resin obtained in Preparation Example 1, 60 parts of PC resin, and 20 parts of glass fiber were melt-mixed at 280 ° C. using a twin screw extruder, and the strand was cut through a steel belt to be repelletized. . The re-pelleted sample was subjected to hot press molding under the conditions described above, and the conductivity was measured and found to be 3 × 10 ² Ω · cm.

Comparative Example 5
28.5 parts of polystyrene used in Comparative Example 1, 50 parts of PC resin, 20 parts of glass fiber, and 1.5 parts of carbon nanotubes were melt-mixed at 280 ° C. using a twin screw extruder, and the strand was cut through a steel belt. Re-pelletized. The re-pelleted sample was subjected to hot press molding under the conditions described above, and the conductivity was measured and found to be 1 × 10 ³ Ω · cm.

Comparative Example 6
19 parts of polystyrene, 60 parts of PC resin, 20 parts of glass fiber, and 1 part of carbon nanotubes used in Comparative Example 1 were melt-mixed at 280 ° C. using a twin screw extruder, cut into strands through a steel belt, and repelletized. . The re-pelleted sample was subjected to hot press molding under the above-described conditions, and the conductivity was measured. As a result, it was 6 × 10 ³ Ω · cm.

Preparation Example 9
In the flask, 50 g of Nanocyl multi-walled carbon nanotubes (9.5 nm × 1.5 μm, bulk density 0.06 g / cm ³ ), 900 g of styrene monomer, 50 g of methyl methacrylate, macromonomer of Reference Example 1 (Mm−1) ) Was added at a monomer ratio of 100 ppm and stirred for 5 minutes. Thereafter, the flask was dispersed with an ultrasonic homogenizer (300 w) for 120 minutes while stirring in an ice bath and stirring. The dispersion monomer was charged into a polymerization apparatus, 100 g of ethylbenzene was added, and the mixture was reacted at 138 ° C. for 7 hours. The polymerization rate after the reaction was 98%. The polymer after the reaction was taken out and dried at 80 ° C. under full vacuum for 48 hours to obtain a polymer. The composition ratio of the obtained polymer was styrene / methyl methacrylate = 95/5, and the weight average molecular weight was 270,000.

Example 11
20 parts of the carbon nanotube-containing styrenic resin obtained in Preparation Example 9 and 80 parts of the PC resin were melt-mixed at 280 ° C. using a twin screw extruder, and strand-cut through a steel belt to be repelletized. Using the re-pelleted sample, hot press molding was performed under the conditions described above, and the conductivity was measured. As a result, it was 8 × 10 ² Ω · cm.

Preparation Example 10
In the flask, 50 g of Nanocyl multi-walled carbon nanotubes (9.5 nm × 1.5 μm, bulk density 0.06 g / cm 3), 900 g of styrene monomer, 50 g of butyl acrylate, macromonomer of Reference Example 1 (Mm-1) Was added at 100 ppm to the monomer and stirred for 5 minutes. Thereafter, the flask was dispersed with an ultrasonic homogenizer (300 w) for 120 minutes while stirring in an ice bath and stirring. The dispersion monomer was charged into a polymerization apparatus, 100 g of ethylbenzene was added, and the mixture was reacted at 138 ° C. for 7 hours. The polymerization rate after the reaction was 98%. The polymer after the reaction was taken out and dried at 80 ° C. under full vacuum for 48 hours to obtain a polymer. The composition ratio of the obtained polymer was styrene / butyl acrylate = 94/6, and the weight average molecular weight was 280,000.

Example 12
20 parts of the carbon nanotube-containing styrenic resin obtained in Preparation Example 10 and 80 parts of the PC resin were melt-mixed at 280 ° C. using a twin-screw extruder, and the strand was cut through a steel belt to be repelletized. The re-pelleted sample was subjected to hot press molding under the above-described conditions, and the conductivity was measured. As a result, it was 7 × 10 ² Ω · cm.

  The evaluation results are shown in Tables 1-5. In addition, about the amount of carbon nanotubes in a table | surface, in the case of the carbon nanotube containing polystyrene, it was set as the parenthesis notation.

  As described above, a resin composition containing a PC resin and a specific master batch obtained by polymerizing carbon nanotubes by mechanically dispersing them in a monomer mixture containing a styrene-based monomer improves the conductivity and moldability. It is obvious.

Claims (8)

Polycarbonate resin (A);
A carbon nanotube-containing styrene system having a weight average molecular weight of 150,000 to 400,000 obtained by RI-GPC obtained by dispersing carbon nanotubes in a monomer mixture containing a styrene monomer and then polymerizing the mixture. Resin (B)
And a polycarbonate-based resin composition. The polycarbonate resin composition according to claim 1, wherein the monomer mixture containing the styrene monomer contains a hyperbranched macromonomer. The polycarbonate resin composition according to claim 2, wherein the multi-branched macromonomer has a weight average molecular weight of 2,000 to 8,000. 4. The monomer mixture containing the styrenic monomer, wherein a blending ratio of the hyperbranched macromonomer with respect to the styrenic monomer is 100 ppm to 2000 ppm on a mass basis. 5. Polycarbonate resin composition. In the resin composition containing the polycarbonate resin (A) and the carbon nanotube-containing styrene resin (B), when the total amount is 100 parts by mass,
The polycarbonate resin composition according to any one of claims 1 to 4, wherein the glass fiber content is 10 to 40 parts by mass. In the resin composition containing the polycarbonate resin (A) and the carbon nanotube-containing styrene resin (B), when the total amount is 100 parts by mass,
The polycarbonate resin composition according to any one of claims 1 to 5, wherein the content of the carbon nanotube is 0.5 to 3 parts by mass. The polycarbonate resin composition according to any one of claims 1 to 6, wherein the carbon nanotube is a multi-walled carbon nanotube. A molded article obtained by using the polycarbonate resin composition according to any one of claims 1 to 7.