WO2016032307A1 - Composite with improved mechanical properties and molded product containing same - Google Patents

Abstract

Provided is a composite which is obtained by processing a resin composition containing a thermoplastic resin, multi-wall carbon nanotubes, and a reinforcement member, wherein the average diameter of the multi-wall carbon nanotubes is 10 nm or more; the number of graphene layers constituting walls of the multi-wall carbon nanotubes is 10 or more; the Id/Ig ratio of the multi-wall carbon nanotube is 1 or less; and the length residual rate of the carbon nanotube which remains in the composite has a value of 40% or more. The thermoplastic resin-containing composite has improved mechanical properties without the deterioration in conductivity, and thus can be manufactured into various molded products.

Description

Composites with improved mechanical properties and molded articles containing them

This application claims the benefit of priority based on Korean Patent Application No. 10-2014-0113752, filed August 29, 2014, and all contents disclosed in the documents of that Korean Patent Application are incorporated as part of this specification.

The present invention relates to a composite having improved mechanical properties and a molded article containing the same.

Thermoplastic resins, particularly high performance plastics with excellent mechanical properties and heat resistance, are used in various applications. For example, since polyamide resins and polyester resins have excellent balance between mechanical properties and toughness, they are used in various electric / electronic parts, mechanical parts, and automobile parts mainly for injection molding. Butylene terephthalate and polyethylene terephthalate are widely used as materials for industrial molded products such as connectors, relays and switches in automobiles and electrical / electronic devices because of their excellent moldability, heat resistance, mechanical properties and chemical resistance. In addition, non-crystalline resins such as polycarbonate resins are excellent in transparency and dimensional stability, and are used in various fields including various optical materials, electric devices, OA devices, and automobile parts.

However, in electrical and electronic parts, antistatic properties such as antistatic and dust pollution prevention are required in order to prevent malfunctions and contamination of parts, and electrical conductivity is required in existing physical properties such as conductivity is required in automobile fuel pump parts. This is additionally required.

In order to impart such electrical conductivity, conventionally, surfactants, metal powders, metal fibers, and the like are added. However, these components lower the physical properties such as low conductivity or weakened mechanical strength.

Although conductive carbon black is commonly used as a material for imparting conductivity to the resin, a large amount of carbon black needs to be added to achieve high electrical conductivity, and the structure of the carbon black may be decomposed during melt mixing. As a result, the workability of resin deteriorates, and also the problem that thermal stability and physical property fall remarkably is caused.

In order to improve the conductivity while reducing the amount of conductive filler added, carbon nanotube-resin composites in which carbon nanotubes are added instead of conductive carbon black have been actively studied.

The problem to be solved by the present invention is to provide a composite having improved mechanical properties while having excellent conductivity.

Another object of the present invention is to provide a molded article having improved mechanical properties while having excellent conductivity.

The present invention to solve the above problems,

Thermoplastic resins;

Multi-walled carbon nanotubes; And

As a composite material obtained by processing the resin composition containing;

The average diameter of the multi-walled carbon nanotubes is 10 nm or more,

Graphene constituting the wall of the multi-walled carbon nanotube is more than 10 layers,

Id / Ig ratio of the multi-walled carbon nanotubes has a value of 1 or less,

The carbon nanotubes remaining in the composite provide a composite having a length residual ratio of 40% or more represented by Equation 1 below:

 <Equation 1>

Length Retention Rate (%) = (content of CNTs having a length of 500 nm or more among CNTs remaining in the composite) / (content of CNTs in the composite) X 100.

In order to solve the said another subject, this invention provides the molded article containing the said composite material.

According to one aspect, a composite material is obtained by extruding a thermoplastic resin including a multi-walled carbon nanotube and a reinforcing material, and the multi-walled carbon nanotube as a raw material has a predetermined range of average diameter and number of graphene walls, resulting in processing. To improve the conductivity and mechanical properties of the composite. In addition, as the carbon nanotubes have a low range of Id / Ig values, the degree of decomposition of the carbon nanotubes in the extrusion process decreases, so that the average length of the carbon nanotubes remaining in the resultant product is increased, thereby improving the conductivity while suppressing the change of physical properties of the thermoplastic resin. Will be displayed. Therefore, the molded article obtained by molding the composite material may be usefully used for various parts requiring conductivity and mechanical properties.

Hereinafter, the present invention will be described in detail. The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best explain their invention in the best way possible. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

Composite according to one embodiment is a thermoplastic resin; Multi-walled carbon nanotubes; And a reinforcing material; a composite material obtained by processing a resin composition comprising a mean diameter of the multi-walled carbon nanotubes is 10 nm or more, and graphene constituting the wall of the multi-walled carbon nanotubes has a range of 10 or more layers. The Id / Ig ratio of the multi-walled carbon nanotubes may have a value of 1 or less. The length residual ratio of the carbon nanotube remaining in the composite provides a composite having a value of 40% or more.

The length residual ratio may be defined according to Equation 1 below:

[Equation 1]

Length Retention Rate (%) = (content of CNTs having a length of 500 nm or more among CNTs remaining in the composite) / (content of CNTs in the composite) X 100.

In order to improve the mechanical properties and conductivity by adding carbon nanotubes and reinforcing materials to the thermoplastic resin, mechanical properties inherent in the thermoplastic resin and deterioration of physical properties of the carbon nanotubes and the reinforcing materials should be minimized. However, since a process such as extrusion requires a high temperature and a high pressure, the raw material components are crushed or cut in such a process so that mechanical properties decrease.

The present invention provides a composite material which can achieve the desired conductivity and mechanical property range by minimizing the deterioration of intrinsic properties of raw materials while minimizing such deterioration of physical properties in the process, and the multi-wall carbon nano used as a raw material for this purpose. The average diameter and wall number of the tubes may be in a predetermined range. Accordingly, the cutting of carbon nanotubes remaining in the composite material is suppressed and the length residual ratio is increased.

In the composite, the Id / Ig ratio represents a ratio relative to the intensity of the D peak (D band) and the G peak (G band) in the Raman spectrum of carbon nanotubes. In general, Raman spectrum of the carbon nanotube is divided into a lower peak of two of the sp ² bonded graphite castle main peak, i.e. 1,100 to 1,400cm ^-1 and 1,500 to a high peak of 1,700cm ^-1. Near 1,300cm ^-1, for example, the first peak (D- band) of 1,350cm ^-1 is incomplete near to the presence of carbon particles and shows properties of the chaotic wall, 1,600cm ^-1, for example, 1580cm ^-1 The second peak (G-band) represents the continuous form of the carbon-carbon bond (CC), which is characteristic of the crystalline graphite layer of carbon nanotubes. The wavelength value may vary somewhat depending on the wavelength of the laser used for the spectral measurement.

The intensity ratio (Id / Ig) of the D-band peak and the G-band peak can be used to evaluate the degree of disorder or defects of carbon nanotubes. If the ratio is high, the disorder or defect can be evaluated to be high, and the ratio is low. In other words, it can be evaluated that the defects of the carbon nanotubes are small and the degree of crystallinity is high. The defects referred to herein refer to incomplete portions of the carbon nanotube array, such as lattice defects, generated due to intrusion of unnecessary atoms as impurities, lack of necessary carbon atoms, or misalignment in the carbon bonds constituting the carbon nanotubes. (lattice defect), which causes the defect portion to be easily cut by an external stimulus.

The intensity of the D-band peak and the G-band peak may be defined as, for example, the height of the center of the X axis or the area of the bottom of the peak in the Raman spectrum, and the height value of the center of the X axis may be adopted in consideration of the ease of measurement. Can be.

According to one embodiment, by limiting the Id / Ig of the carbon nanotubes used as a raw material in the range of 0.01 to 1.0, for example 0.01 to 0.7, or 0.01 to 0.5, the carbon nanotubes remaining in the resulting composite material It can improve the average length of. The improved average length may be represented by the length residual ratio of Equation 1 below.

[Equation 1]

Length Retention Rate (%) = (content of CNTs with a length of 500 nm or more among CNTs remaining in the composite) / (content of CNTs in the composite) X 100

When the length residual ratio is large, the conductivity of the thermoplastic resin may be increased by only a smaller amount of carbon nanotubes, which is more advantageous for maintaining the physical properties of the resin.

In the present invention, the carbon nanotubes added to the thermoplastic resin have a predetermined diameter range and a predetermined number of layers, and at the same time limit the Id / Ig value to a predetermined range, thereby selectively extruding them by selectively using hard carbon nanotubes with few defects. Even processing in the process can reduce the content to be cut. That is, since the content of carbon nanotubes cut by the external magnetic poles generated during the processing decreases, the length residual ratio may be increased.

As such, increasing the length residual ratio corresponds to a more advantageous structure for improving conductivity of the thermoplastic resin. Since the carbon nanotubes have a network structure in the matrix of the thermoplastic resin, carbon nanotubes having a longer length remaining in the resultant are more advantageous in forming such a network, and as a result, the frequency of contact between networks decreases. The contact resistance value is reduced, which contributes to the increased conductivity.

According to one embodiment, the carbon nanotubes have a length remaining ratio of 40% or more, for example, 40% to 99%, or 40% to 90%, or 45% to 90%. In this range, while improving the conductivity of the resulting composite material, it is possible to suppress the deterioration of mechanical properties and at the same time maintain workability.

Carbon nanotubes used in the present invention is a kind of carbon allotrope and carbon atoms are bonded in the form of hexagonal honeycomb to form a tube, and the diameter of the nanometer refers to a material having an extremely small area.

Such carbon nanotubes have a form where the graphene surface is rounded to a diameter of nanometer level, and the graphene surface may have various structures having different characteristics depending on the angle and shape of the graphene surface being dried. According to the number of walls of the graphene surface (Wall) can be divided into single-walled carbon nanotubes (SWCNT) or multi-walled carbon nanotubes (MWCNT).

Compared to the single-walled carbon nanotubes, the multi-walled carbon nanotubes have less damage such as cutting in the composite forming process, resulting in a longer length after processing, thereby improving the mechanical strength and electrical conductivity of the composite product as a result of processing. You can contribute more.

According to one embodiment, the multi-walled carbon nanotubes used in forming the composite according to the present invention has a graphene surface constituting a wall of 10 or more layers, for example, 10 to 50 layers, or 10 to 30 layers It can have a range. The multi-walled carbon nanotube having a graphene surface of about 10 layers or more may further improve mechanical strength when forming a composite material.

In addition, according to one embodiment, the multi-walled carbon nanotubes used as raw materials for forming the composite according to the present invention may have an average diameter of about 10 nm or more, for example, about 10 nm to about 30 nm. Multi-walled carbon nanotubes having an average diameter in the above range can be prevented from decreasing the mechanical strength and electrical conductivity of the resulting composite material because the reduction of the remaining length is suppressed even after the extrusion process.

According to one embodiment, the multi-walled carbon nanotubes used as a raw material may have an average length of about 500 nm or more, for example, 800 nm to 1,000 μm, or 800 nm to 300 μm. Multi-walled carbon nanotubes having an average length in this range corresponds to a more advantageous structure for improving the conductivity of the thermoplastic resin-containing composite.

According to one embodiment, the average length of the multi-walled carbon nanotube remaining in the thermoplastic resin-containing composite material may be 0.5 ㎛ or more, or 0.6 ㎛ or more, or 0.7 ㎛ or more, 50 ㎛ or less or 30 ㎛ or less or 10 ㎛ or less Can be.

The multi-walled carbon nanotubes as described above may be used in an amount of about 0.1 to about 10 parts by weight, or about 0.1 to 5 parts by weight based on 100 parts by weight of the thermoplastic resin, and within this content, the inherent mechanical properties of the thermoplastic resin It is possible to improve conductivity while minimizing degradation of physical properties.

The multi-walled carbon nanotubes can be used in a bundle type or a non-bundle type without limitation.

As used herein, the term 'bundle' refers to a bundle or rope form in which a plurality of carbon nanotubes are arranged or entangled side by side, unless otherwise stated. 'Non-bundle or entangled' type means a shape without a constant shape, such as a bundle or rope shape.

Such a bundle-type multi-walled carbon nanotubes may basically have a shape in which a plurality of multi-walled carbon nanotube strands are gathered together to form a bundle, and the plurality of strands may be straight, curved, or a mixture thereof. Have In addition, the bundle of carbon nanotubes may also have a linear, curved or mixed form thereof.

According to one embodiment, the bundle of carbon nanotubes used in the preparation of the thermoplastic resin-containing composite has a relatively high bulk density, which may be more advantageous for improving the conductivity of the composite. The bulk density of the carbon nanotubes may have a range of 80 to 250 kg / m ³ , for example 100 to 220 kg / m ³ .

According to one embodiment, the reinforcing material used when forming the composite material may use a material having a fiber shape. Such a fibrous reinforcement may be included in the matrix of the thermoplastic resin to form a network structure, and may also have a tangled structure with the structure of the multi-walled carbon nanotubes, thereby improving the mechanical strength of the composite as a result of the processing. You can do it.

Any of these fibrous reinforcing materials can be used without limitation as long as they have a fibrous shape. Carbon fiber, glass fiber, pulverized glass fiber, aramid fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, gypsum fiber One or more metal fibers.

The carbon fiber may be carbon-based or graphite-based, and specifically, the carbon fiber belonging to the carbon-based may include carbon powder, carbon fine particles, carbon black, carbon fiber, and the like. More specifically, it is preferable to use acicular carbon fibers having a diameter of about 5 to about 15 μm and a length of about 100 to about 900 μm, with an aspect ratio (ratio of height to length L / H) of 250 to 1600 carbons. Preference is given to using fibers.

Glass fiber, which is the fiber-shaped reinforcing material, is conventionally used commercially, and glass fiber having a diameter of about 8 to about 20 μm and a length of about 1.5 to 8 mm may be used. If the diameter of the glass fiber has the above range it can be obtained an effect of excellent impact reinforcement. In addition, when the length of the glass fiber has the above range it is easy to put in the extruder or injection machine and the impact reinforcing effect can be greatly improved.

The glass fiber may be selected from the group consisting of a circular cross-section, elliptical, rectangular and two circular connected dumbbell shape. In addition, it is possible to use flat glass fibers, which are special glass fibers, which are doped with an area of 25 to 30 µm X 5 to 10 µm in length and 2 to 7 mm in length, in particular the processability and surface and mechanical properties of the thermoplastic resin composition, in particular It is preferable in terms of increasing the bending strength.

The glass fiber may be treated with a predetermined glass fiber treatment agent to prevent the reaction with the thermoplastic resin and to improve the degree of impregnation. Treatment of the glass fiber may be processed at the time of fiber manufacture or in a later step.

Lubricating agents, coupling agents, surfactants and the like are used as the glass fiber treatment agent. The lubricant is used to form a good strand having a constant diameter thickness in the manufacture of glass fibers, the coupling agent serves to give a good adhesion between the glass fiber and the resin. When such various glass fiber treatment agents are appropriately selected and used according to the type of resin and glass fiber used, the glass fiber reinforcement material has good physical properties.

The reinforcing material may be included in an amount of 0.1 to 50 parts by weight with respect to 100 parts by weight of the thermoplastic resin, and when the reinforcing material is included in the above range, while improving the mechanical strength of the resin composition and the molded body, bringing excellent flowability and excellent processability and molding The castle can be secured.

As the component for forming the composite, carbonaceous conductive additives may be further included in addition to the thermoplastic resin, the multi-walled carbon nanotubes, and the reinforcing material. As such carbon-based conductive additives, carbon black, graphene, carbon nanofibers, fullerenes, carbon nanowires, and the like may be used. They may be added in an amount of about 0.1 to 30 parts by weight based on 100 parts by weight of the thermoplastic resin. In such a range, it is possible to more improve their conductivity without deteriorating the physical properties of the resin composition.

As the carbon black used as the carbon-based conductive additive, furnace black, channel black, acetylene black, lamp black, thermal black, Ketjen black, and the like may be used, but are not limited thereto. An average particle diameter of the carbon black may be 20 to 100 μm, and conductivity may be efficiently improved in such a range.

Graphene, which is used as the carbon-based conductive additive, is a two-dimensional carbon allotrope, and a method of preparing the same includes a peeling method of physically separating a layer of graphene from graphite, and chemically reducing the graphite by dispersing it in a dispersion. Chemical oxidation / reduction method to obtain fin, pyrolysis method to obtain graphene layer through high temperature pyrolysis on silicon carbide (SiC) substrate, and chemical vapor deposition method, among which chemical vapor deposition method can synthesize high quality graphene. It can be illustrated as a method.

According to one embodiment, the graphene may exhibit a characteristic aspect ratio of 0.1 or less, graphene layer number of 100 or less, and a specific surface area of 300 m ² / g or more. The graphene refers to a single mesh plane of SP ² bonds of carbon (C) in the hcp structure of graphite, and recently, graphene composite layers having a plurality of layers are also classified as graphene in a broad sense.

According to one embodiment, the carbon nanofibers used as the carbon-based conductive additive has a high specific surface area, excellent electrical conductivity, adsorption, and the like, and the carbon material produced by decomposition and growth of a gaseous compound containing carbon at high temperature It can be obtained by growing in the form of fibers in a metal catalyst prepared in advance. Thermally decomposed carbon is accumulated in the form of graphene layers through adsorption, decomposition, absorption, diffusion, and precipitation in a specific metal catalyst surface of several nanometers in size to form carbon nanofibers having excellent crystallinity and purity. Can be. Carbon nanofibers formed on the catalyst particles of transition metals such as nickel, iron, and cobalt grow to a nano size, which is 100 times thinner than that of other general-purpose carbon fibers having a diameter of 10 μm. It is more useful because of its high specific surface area and excellent electrical conductivity, adsorptivity and mechanical properties.

Synthesis methods of the carbon nanofibers mainly include electric discharge, laser deposition, plasma chemical vapor deposition, and chemical vapor deposition (CVD). Factors affecting the growth of carbon nanofibers include temperature, carbon source, catalyst, and substrate type. Among them, the diffusion action of the substrate and the catalyst particles and the difference in the interfacial action between each other affect the shape and microstructure of the synthesized carbon nanofibers.

As used herein, the term "bulk density" means the apparent density of the carbon nanotubes in the raw material state, and can be expressed as a value obtained by dividing the weight of the carbon nanotubes by volume.

According to one embodiment, the thermoplastic resin-containing composite material is a flame retardant, impact modifier, flame retardant, flame retardant aid, lubricant, plasticizer, heat stabilizer, anti-dropping agent, antioxidant, compatibilizer, light stabilizer, pigment, dye, inorganic additives and drip prevention agent It may further include an additive selected from the group consisting of, the content may be used in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin. Specific kinds of these additives are well known in the art, and examples which can be used in the composition of the present invention may be appropriately selected by those skilled in the art.

According to one embodiment, the thermoplastic resin used to manufacture the composite material can be used without limitation as long as it is used in the art, for example, polycarbonate resin, polypropylene resin, polyamide resin, aramid resin, aromatic polyester resin, Polyolefin resin, polyester carbonate resin, polyphenylene ether resin, polyphenylene sulfide resin, polysulfone resin, polyether sulfone resin, polyarylene resin, cycloolefin resin, polyetherimide resin, polyacetal resin, polyvinyl Acetal resin, polyketone resin, polyetherketone resin, polyetheretherketone resin, polyarylketone resin, polyethernitrile resin, liquid crystal resin, polybenzimidazole resin, polyparabanic acid resin, aromatic alkenyl compound, methacrylic acid Esters, acrylic esters, and vinyl cyanide compounds. Vinyl polymer or copolymer resin obtained by superposing | polymerizing or copolymerizing 1 or more types of vinyl monomers chosen from the group which consists of a resin, a diene-aromatic alkenyl compound copolymer resin, a vinyl cyanide-diene-aromatic alkenyl compound copolymer resin, and an aromatic Alkenyl compound-diene-vinyl cyanide-N-phenylmaleimide copolymer resin, vinyl cyanide- (ethylene-diene-propylene (EPDM))-aromatic alkenyl compound copolymer resin, polyolefin, vinyl chloride resin, chlorinated vinyl chloride resin At least one selected from the group consisting of may be used. Specific kinds of these resins are well known in the art and may be appropriately selected by those skilled in the art.

Examples of the polyolefin resins include, but are not limited to, polypropylene, polyethylene, polybutylene, and poly (4-methyl-1-pentene), and combinations thereof. In one embodiment, the polyolefin may be a polypropylene homopolymer (e.g., atactic polypropylene, isotactic polypropylene, and syndiotactic polypropylene), polypropylene copolymer (e.g., Polypropylene random copolymers), and mixtures thereof. Suitable polypropylene copolymers include, but are not limited to, the presence of comonomers selected from the group consisting of ethylene, but-1-ene (ie 1-butene), and hex-1-ene (ie 1-hexene). Random copolymers prepared from the polymerization of propylene under. In such polypropylene random copolymers, comonomers may be present in any suitable amount, but typically in amounts of about 10 wt% or less (eg, about 1 to about 7 wt%, or about 1 to about 4.5 wt%) May exist.

As said polyester resin, the homopolyester and copolyester which are polycondensates of a dicarboxylic acid component skeleton and a diol component skeleton are mentioned. As the homo polyester, for example, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, poly-1,4-cyclohexanedimethylene terephthalate, polyethylene diphenylate Etc. are typical. In particular, since polyethylene terephthalate is inexpensive, it can be used for a very wide range of applications, which is preferable. In addition, the said copolyester is defined as the polycondensate which consists of at least 3 or more components chosen from the component which has a dicarboxylic acid skeleton and the component which have a diol skeleton which are illustrated next. Examples of the component having a dicarboxylic acid skeleton include terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4 ' -Diphenyl dicarboxylic acid, 4,4'- diphenyl sulfone dicarboxylic acid, adipic acid, sebacic acid, dimer acid, cyclohexanedicarboxylic acid, ester derivatives thereof, and the like. Examples of the component having a glycol skeleton include ethylene glycol, 1,2-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentadiol, diethylene glycol, polyalkylene glycol, 2,2-bis ( 4 '-(beta) -hydroxyethoxyphenyl) propane, isosorbate, 1, 4- cyclohexane dimethanol, spiroglycol, etc. are mentioned.

As the polyamide resin, nylon resin, nylon copolymer resin and mixtures thereof can be used. As a nylon resin, Polyamide-6 (nylon 6) obtained by ring-opening-polymerizing lactams, such as well known epsilon caprolactam and ω-dodecaractam; Nylon polymers obtainable from amino acids such as aminocaproic acid, 11-aminoundecanoic acid and 12-aminododecanoic acid; Ethylenediamine, tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 5-methylnonahexamethylenediamine , Metaxylenediamine, paraxylenediamine, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis ( 4-aminocyclohexane) methane, bis (4-methyl-4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) propane, bis (aminopropyl) piperazine, aminoethylpiperidine, etc. Aliphatic, cycloaliphatic or aromatic diamines and aliphatic, cycloaliphatic or aromatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, terephthalic acid, 2-chloroterephthalic acid and 2-methylterephthalic acid Nylon polymers obtainable from the polymerization of; Copolymers or mixtures thereof can be used. As the nylon copolymer, a copolymer of polycaprolactam (nylon 6) and polyhexamethylene sebacamide (nylon 6,10), a copolymer of polycaprolactam (nylon 6) and polyhexamethyleneadipamide (nylon 66), And copolymers of polycaprolactam (nylon 6) and polylauryllactam (nylon 12).

The polycarbonate resin may be prepared by reacting diphenols with phosgene, halogen formate, carbonate ester or a combination thereof. Specific examples of the diphenols include hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, 2,2-bis (4-hydroxyphenyl) propane (also called 'bisphenol-A'), 2, 4-bis (4-hydroxyphenyl) -2-methylbutane, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 2,2-bis (3-chloro 4-hydroxyphenyl) propane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane, 2 , 2-bis (3,5-dibromo-4-hydroxyphenyl) propane, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ketone, bis (4-hydroxyphenyl) Ether and the like. Among these, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane or 1,1-bis (4-hydroxyphenyl) Cyclohexane can be used, more preferably 2,2-bis (4-hydroxyphenyl) propane.

The polycarbonate resin may be a mixture of copolymers prepared from two or more diphenols. In addition, the polycarbonate resin may be used a linear polycarbonate resin, branched (branched) polycarbonate resin, polyester carbonate copolymer resin and the like.

Bisphenol-A type | system | group polycarbonate resin etc. are mentioned as said linear polycarbonate resin. Examples of the branched polycarbonate resins include those produced by reacting polyfunctional aromatic compounds such as trimellitic anhydride, trimellitic acid, and the like with diphenols and carbonates. The polyfunctional aromatic compound may be included in an amount of 0.05 to 2 mol% based on the total amount of the branched polycarbonate resin. As said polyester carbonate copolymer resin, what was manufactured by making bifunctional carboxylic acid react with diphenols and a carbonate is mentioned. In this case, as the carbonate, diaryl carbonate such as diphenyl carbonate, ethylene carbonate, or the like may be used.

As said cycloolefin type polymer, a norbornene type polymer, a monocyclic cyclic olefin type polymer, a cyclic conjugated diene type polymer, a vinyl alicyclic hydrocarbon polymer, and these hydrides are mentioned. Specific examples thereof include Apel (ethylene-cycloolefin copolymer manufactured by Mitsui Chemical Co., Ltd.), aton (norbornene-based polymer manufactured by JSR Corporation), zeonoa (norbornene-based polymer manufactured by Nippon Xeon Corporation), and the like.

According to one embodiment, the method for producing the thermoplastic resin-containing composite is not particularly limited, but the mixture of raw materials is supplied to a conventionally known melt mixer such as a single screw or twin screw extruder, Banbury mixer, kneader, mixing roll, or the like, to about 100 to 500. The method of kneading at the temperature of 200 degreeC, or 200-400 degreeC, etc. are mentioned as an example.

In addition, the mixing order of the raw materials is not particularly limited, and the above-mentioned thermoplastic resin, carbon nanotubes having an average length in the above-mentioned range, and additives, if necessary, are blended in advance and then shortened or above the melting point of the thermoplastic resin. The method of melt-kneading uniformly with a twin screw extruder, the method of removing a solvent after mixing in a solution, etc. are used. Among them, from the viewpoint of productivity, a method of uniformly melt kneading with a single screw or twin screw extruder is preferable, and a method of uniformly melt kneading above the melting point of the thermoplastic resin using a twin screw extruder is particularly preferably used.

As the kneading method, a thermoplastic resin, a method of kneading carbon nanotubes in a batch, a resin composition (master pellet) containing carbon nanotubes in high concentration in a thermoplastic resin are prepared, and then the resin composition and carbon are formed so as to have a specified concentration. The method (master pellet method) etc. which melt-knead by adding a nanotube can be illustrated, and what kneading method may be used. As another method, in order to suppress the breakage of carbon nanotubes, a thermoplastic resin and other necessary additives are introduced from the extruder side, and the carbon nanotubes are fed to the extruder using a side feeder to produce a composite material. This is preferably used.

Through the extrusion method it is possible to produce a composite having a form such as pellets.

According to one embodiment, the average length of the carbon nanotubes used as the raw material for the production of the composite can be measured through a scanning electron microscope (SEM) or a transmission electron microscope (TEM). That is, after obtaining a photograph of powdered carbon nanotubes as raw materials through these measuring devices, the average length was analyzed by an image analyzer, for example, Scandium 5.1 (Olympus soft Imaging Solutions GmbH, Germany). You can get it.

In the case of the carbon nanotubes contained in the composite material, the resin solids may be organic solvents such as acetone, ethanol, n-hexane, chloroform, p-xylene, 1-butanol, petroleum ether, 1,2,4-trichloro After being dispersed at a predetermined concentration in benzene, dodecane and the like, the resultant measured by SEM or TEM using this dispersion can be analyzed using the image analyzer to obtain an average length and distribution state.

The composite obtained through the above method does not deteriorate in mechanical strength, and there is no problem in the production process and the secondary processability, and a carbon nanotube-thermoplastic resin composite having sufficient electrical properties while adding a small amount of carbon nanotube is obtained. Can be.

The composite material according to one embodiment can be molded by any method such as injection molding, blow molding, press molding, spinning, or the like, which can be processed into various molded articles. As a molded article, it can use as an injection molded article, an extrusion molded article, a blow molded article, a film, a sheet, a fiber, etc.

As the method for producing the film, a known melt film forming method may be employed, and for example, the raw materials are melted in a single screw or twin screw extruder, and then extruded from a film die and cooled on a cooling drum to produce an unstretched film. The uniaxial stretching method, the biaxial stretching method, etc. which extend | stretch suitably longitudinally and horizontally by the roller type longitudinal stretch apparatus and the horizontal stretching apparatus called a tenter can be illustrated. .

As said fiber, it can use as various fibers, such as undrawn yarn, drawn yarn, and super drawn yarn, As a manufacturing method of the fiber using the said resin composition, a well-known melt spinning method can be applied, For example, the resin composition which is a raw material Kneading while supplying a chip consisting of a single chip or a twin screw extruder, and then extruded from a spinneret through a polymer flow line switcher, a filtration layer, etc. provided at the tip of the extruder, and cooled. , Stretching, thermal setting, or the like can be employed.

The composite material of the present invention has a tensile strength of 83 MPa or more, or 95 MPa or more, or 100 MPa or more, and the tensile modulus of the composite material is 3.3 GPa or more, or 4 GPa or more, or 5 GPa or more, and the surface specific resistance is 1.0 x 10. ⁹ Ω / sq. It may be the following.

In particular, the composite material of the present invention can be processed into a molded article such as an electric charge shield, an electrical / electronic product housing, an electrical / electronic component, taking advantage of its excellent conductivity and excellent mechanical properties.

According to one embodiment, the various molded articles can be used for various applications such as automobile parts, electrical / electronic parts, building members, and the like. Specific applications include air flow meters, air pumps, thermostat housings, engine mounts, ignition bobbins, ignition cases, clutch bobbins, sensor housings, idle speed control valves, vacuum switching valves, ECU housings, vacuum Pump case, inhibitor switch, rotation sensor, acceleration sensor, distributor cap, coil base, actuator case for ABS, top and bottom of radiator tank, cooling fan, fan shroud, engine cover, cylinder head cover, oil cap , Oil pan, oil filter, fuel cap, fuel strainer, distributor cap, vapor canister housing, air cleaner housing, timing belt cover, brake booster parts, various cases, various tubes, various tanks, various hoses, various Automotive under hood parts such as clips, valves, and pipes, torque control levers , Seat belt parts, resistor blades, washer levers, wind regulator handles, knobs of wind regulator handles, passing light levers, sun visor brackets, automotive interior parts such as various motor housings, roof rails, fenders, garnishes, Automotive exterior parts such as bumpers, door mirror stays, spoilers, hood louvers, wheel covers, wheel caps, grille apron cover frames, lamp reflectors, lamp bezels, door handles, wire harness connectors, SMJ connectors, PCB Connectors, door grommet connectors, automotive connectors, relay cases, coil bobbins, optical pickup chassis, motor cases, notebook PC housings and interior components, LED display housings and interior components, printer housings and interior components, mobile phones Terminal housings and internal components such as electronics, mobile PCs and portable mobile devices, recording media (CD, DVD, PD, FDD, etc.) drives There may be mentioned electric and electronic parts typified by the housing and internal components, a housing and inner parts of copying machine, facsimile housings and internal parts of the parabolic antenna and the like.

In addition, VTR parts, television parts, irons, hair dryers, rice cooker parts, microwave oven parts, acoustic components, video camera parts, such as projectors, laser disk (registered trademark), compact disk (CD), CD-ROM Boards, lighting components, refrigerator components, air conditioner components, typewriter components, word processors for optical recording media such as CD-R, CD-RW, DVD-ROM, DVD-R, DVD-RW, DVD-RAM, Blu-ray Disc For example, home and office electrical appliance parts represented by components.

In addition, housings and internal parts of electronic musical instruments, home game machines, portable game machines, various gears, various cases, sensors, LEP lamps, connectors, sockets, resistors, relay cases, switches, coil bobbins, capacitors, variable capacitors, and the like. Case, optical pickup, oscillator, various terminal board, transformer, plug, printed wiring board, tuner, speaker, microphone, headphones, small motor, magnetic head base, power module, semiconductor, liquid crystal, FDD carriages, FDD chassis, motor It is especially useful as an electric / electronic component such as a brush holder, a trans member, a coil bobbin, or various automotive connectors such as a wire harness connector, an SMJ connector, a PCB connector, a door grammant connector, and the like.

On the other hand, since the molded article has improved conductivity, it can be used as an electromagnetic shield by absorbing electromagnetic waves. The electromagnetic shielding body absorbs and extinguishes electromagnetic waves, thus exhibiting improved performance in the electromagnetic wave absorbing ability.

In addition, the thermoplastic resin-containing composite of the present invention and the molded article constituted therefrom can be recycled. For example, the resin composition obtained by pulverizing the said composite material and a molded article, making it into powder shape preferably, and mix | blending an additive as needed can be used similarly to the composite material of this invention, and can also be made into a molded article.

Hereinafter, the present invention will be described in detail with reference to Examples. However, embodiments according to the present invention can be modified in many different forms, the scope of the present invention should not be construed as limited to the embodiments described below. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

<Example>

Each component and additives used in the following Examples and Comparative Examples are as follows.

(a) polyamide resin

LG Chem's LUMID GP-1000B was used.

(b) carbon nanotubes

The multi-walled carbon nanotubes having various I _D / I _G ratios, average lengths, average diameters, and graphene plane layer numbers shown in Table 1 were used.

<Examples 1 to 6 and Comparative Examples 1 to 5>

The carbon nanotubes and glass fibers of the contents shown in Table 1 were mixed together with the polyamide resin having a total amount of 100% by weight. The resulting mixture was then extruded in a twin screw extruder (L / D = 42, Φ = 40 mm) while raising the temperature profile to 280 ° C. to produce pellets having a size of 0.2 mm × 0.3 mm × 0.4 mm.

The prepared pellets were injected into a flat profile at an injection temperature of 280 ° C. to prepare specimens having a thickness of 3.2 mm, a length of 12.7 mm, and a dog-bone shape. The prepared specimen was allowed to stand for 48 hours at 23 ℃, 50% relative humidity.

The bundle average length and average diameter of the carbon nanotubes as the raw material are measured by scanning a SEM photograph of the powdery multi-walled carbon nanotubes as the raw material by Scandium 5.1 (Olympus soft Imaging Solutions GmbH, Germany).

The characteristics of the specimens were measured by the following method, and the results are shown in Table 1 below, respectively.

-Tensile strength and tensile modulus

The specimens obtained in Examples 1 to 6 and Comparative Examples 1 to 5 were evaluated for tensile strength and tensile modulus of the specimen having a thickness of 3.2 mm according to ASTM D638 standard.

Surface specific resistance (Ω / cm)

The specimens obtained in Examples 1 to 6 and Comparative Examples 1 to 5 were measured using PINION's SRM-100 according to ASTM D257.

-Average length of remaining carbon nanotubes

The residual average length was obtained by dispersing the pellet in chloroform to obtain a dispersion having a concentration of 0.1 g / l, and then obtaining a TEM image (Libra 120, Carl Zeiss Gmbh, Germany) obtained by SCANDIUM 5.1 (Olympus Soft Imaging Solutions GmbH). Analyzed.

Table 1

division		Example						Comparative example
		One	2	3	4	5	6	One	2	3	4	5
Glass fiber content (% by weight)		10	10	10	10	10	10	10	10	10	10	10
CNT	Content (wt%)	1.5	1.5	1.5	1.5	1.5	1.5	0	1.5	1.5	1.5	1.5
	Pristine Length (nm)	1500	1500	1400	1600	1800	1700	-	1500	1500	1400	1600
	Id / Ig Ratio	0.8	0.6	0.8	0.8	0.8	0.6	-	1.2	0.8	0.8	0.8
	Average diameter (nm)	10	10	20	10	20	20	-	10	5	10	5
	Floor count of CNT wall	10	10	10	20	20	20	-	10	10	5	5
	Remaining CNT Average Length (nm)	750	900	850	950	1250	1241	-	540	510	500	330
	Length Survival Rate (%)	50	60	61	59	69	73	-	36	34	36	21
Composite Properties	Tensile Strength (MPa)	108	113	108	116	131	130	104	106	102	102	101
	Tensile Modulus (GPa)	5.0	5.5	5.3	5.8	6.4	6.4	4.6	4.8	4.8	4.8	4.8
	Surface specific resistance (Ω / sq.)	1 × 10 7	1 × 10 6	1 × 10 8	1 × 10 7	1 × 10 8	1 × 10 8	> 1 × 10 14	1 × 10 11	1 × 10 10	1 × 10 11	1 × 10 11

As shown in Table 1, it can be seen that the composite obtained in accordance with Examples 1 to 6 has a long residual length after processing, and has improved electrical conductivity while having excellent tensile strength and tensile modulus. On the contrary, the composites obtained according to Comparative Examples 1 to 5 generally exhibit lower values of tensile strength and tensile modulus than those of the composites obtained in Examples 1 to 6, in particular, a length residual ratio of 40% or less. Accordingly, it can be seen that the conductivity is lowered due to the high surface resistivity.

<Example 7>

Table 2 was carried out in the same manner as in Example 1, except that carbon nanotubes, glass fibers, and carbon black of the contents shown in Table 2 were mixed with the polyamide resin having a total amount of 100% by weight. It was prepared, the results of measuring the physical properties in the same manner are shown in Table 2 below.

TABLE 2

division		Example 7
Glass fiber content (% by weight)		10
Carbon black content (% by weight)		3
CNT	Content (% by weight)	1.5
	Pristine Length (nm)	1650
	I D / I G Ratio	0.6
	Average diameter (nm)	19
	Floor count of CNT wall	20
	Remaining CNT Average Length (nm)	1238
	Length Survival Rate (%)	75
Composite Properties	Tensile Strength (MPa)	130
	Tensile Modulus (GPa)	6.5
	Surface specific resistance (Ω / sq.)	1 × 10 6

As shown in Table 2, in Example 7, it can be seen that as the carbon black is further added as a conductive additive, the tensile modulus and conductivity are further improved.

Claims (21)

1. Thermoplastic resins;

   Multi-walled carbon nanotubes; And

   As a composite material obtained by processing the resin composition containing;

   The average diameter of the multi-walled carbon nanotubes is 10 nm or more,

   Graphene constituting the wall of the multi-walled carbon nanotubes is 10 or more layers,

   Id / Ig ratio of the multi-walled carbon nanotube is 1 or less,

   The carbon nanotube remaining in the composite material has a length residual ratio of 40% or more, which is defined by Equation 1 below:

   <Equation 1>

   Length Retention Rate (%) = (content of CNTs having a length of 500 nm or more among CNTs remaining in the composite) / (content of CNTs in the composite) X 100.
2. The method of claim 1,

   Wherein the Id / Ig has a value between 0.01 and 0.7.
3. The method of claim 1,

   And wherein the length residual ratio is 40% to 99%.
4. The method of claim 1,

   Composite of which the average diameter of the multi-walled carbon nanotubes is 10 to 30 nm.
5. The method of claim 1,

   Graphene constituting the wall of the multi-walled carbon nanotube composite material is 10 to 50 layers.
6. The method of claim 1,

   And wherein the composite has a tensile strength of at least 83 MPa.
7. The method of claim 1,

   And wherein the composite has a tensile modulus of at least 3.3 GPa.
8. The method of claim 1,

   Composite having a surface specific resistance of less than 1.0 x 10 ⁹ Ω / sq.
9. The method of claim 1,

   The multi-walled carbon nanotubes are bundled or unbundled.
10. The method of claim 1,

    The multi-walled carbon nanotube content is 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin.
11. The method of claim 1,

    Composite material having an average length of the multi-walled carbon nanotubes remaining in the composite material is 0.5 ㎛ to 50 ㎛.
12. The method of claim 1,

    Composite, wherein the reinforcing material has a fibrous structure.
13. The method of claim 1,

    And wherein the reinforcing material is at least one of carbon fiber, glass fiber, crushed glass fiber, aramid fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, gypsum fiber and metal fiber.
14. The method of claim 1,

    The content of the reinforcing material is 0.1 to 50 parts by weight based on 100 parts by weight of the thermoplastic resin.
15. The method of claim 1,

    Composite further comprising a carbon-based conductive additive.
16. The method of claim 15,

    The carbon-based conductive additive is one or more of carbon black, graphene, fullerene and carbon nanofibers.
17. The method of claim 15,

    The content of the carbon-based conductive additive is 0.1 to 30 parts by weight based on 100 parts by weight of the thermoplastic resin.
18. The method of claim 1,

    Composite, wherein the processing process is an extrusion process.
19. The molded article obtained by processing the composite material in any one of Claims 1-18.
20. The method of claim 19,

    A molded article, wherein the processing step is an extrusion step, an injection step, or a combination thereof.
21. The method of claim 19,

    Molded parts that are charge shields, electrical / electronic housings, or electrical / electronic components.