(19)
(11)EP 3 326 791 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
02.09.2020 Bulletin 2020/36

(21)Application number: 16900597.2

(22)Date of filing:  17.10.2016
(51)International Patent Classification (IPC): 
C08L 25/06(2006.01)
B29C 70/88(2006.01)
C08K 5/00(2006.01)
B29C 70/02(2006.01)
(86)International application number:
PCT/KR2016/011633
(87)International publication number:
WO 2017/188524 (02.11.2017 Gazette  2017/44)

(54)

ANTISTATIC CARBON COMPOSITE, MOLDED PRODUCT, AND PREPARATION METHOD THEREFOR

ANTISTATISCHES KOHLENSTOFFVERBUNDMATERIAL, FORMPRODUKT UND HERSTELLUNGSVERFAHREN DAFÜR

COMPOSITE DE CARBONE ANTISTATIQUE, PRODUIT MOULÉ ET PROCÉDÉ DE PRÉPARATION ASSOCIÉ


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 25.04.2016 KR 20160049776

(43)Date of publication of application:
30.05.2018 Bulletin 2018/22

(73)Proprietor: LG Chem, Ltd.
Seoul 07336 (KR)

(72)Inventors:
  • KIM, Pyeong-Gi
    Daejeon 34122 (KR)
  • KIM, Seokwon
    Daejeon 34122 (KR)
  • KIM, Se Hyun
    Daejeon 34122 (KR)
  • KIM, Tae Hyung
    Daejeon 34122 (KR)
  • CHOI, Suk Jo
    Daejeon 34122 (KR)
  • CHO, Dong Hyun
    Daejeon 34122 (KR)

(74)Representative: Goddar, Heinz J. 
Boehmert & Boehmert Anwaltspartnerschaft mbB Pettenkoferstrasse 22
80336 München
80336 München (DE)


(56)References cited: : 
KR-B1- 101 505 063
US-A1- 2011 201 731
US-A1- 2015 352 818
US-A1- 2008 067 711
US-A1- 2012 145 315
  
  • DATABASE CA [Online] CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; 6 July 2010 (2010-07-06), MAO, CHENGYU: "Conductive polycarbonate blend and its preparation method", XP002782652, retrieved from STN Database accession no. 2010:828428 -& CN 101 759 987 A (MAO CHENGYV) 30 June 2010 (2010-06-30)
  • DATABASE CA [Online] CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; 10 April 2009 (2009-04-10), KAIGE, KAZUNORI ET AL: "Carbon nanotube -containing resin article, manufacture thereof, method for improving its electric conductivity by heat treatment, and its application", XP002782653, retrieved from STN Database accession no. 2009:425416 -& JP 2009 074072 A (HODOGAYA CHEMICAL CO LTD) 9 April 2009 (2009-04-09)
  • DATABASE CA [Online] CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; 13 December 2010 (2010-12-13), CHO, HYEONG JIN: "Electrically conductive heat-generating polymer compositions yarns", XP002782654, retrieved from STN Database accession no. 2010:1545282 -& KR 2010 0127953 A (JO HYUNG JIN [KR]; LIM JONG YUL [KR]; KIM BYUNG PIL [KR]) 7 December 2010 (2010-12-07)
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

BACKGROUND OF THE INVENTION



[0001] The present invention relates to an antistatic carbon composite, a molded product and a preparation method therefor. More particularly, it relates to a composite, a molded product and a preparation method therefor, that allows to improve mechanical properties including electrical conductivity with a low content of carbon materials.

2. Description of the Related Art



[0002] In recent years, miniaturization, high integration and high performance of electronic products have been achieved due to the development of the technology of electronic products. Accordingly, electrically conductive materials are used to prevent electrical damage that may occur during transport and storage of materials such as electronic products and parts.

[0003] Examples of those used for such applications include a transfer cart for electronic components, a coating material of transfer pipe for electronic components and a thermoforming tray for electronic components (IC tray). They have been used for transferring between manufacturing processes of a semiconductor chip and for packaging after manufacturing. Such trays are determined in size and shape depending on the type or the kind of the semiconductor chip, and they can serve to prevent damage such as electrical shock caused by dust, moisture to a component printed with a circuit. The cart, or the pipe tray may be subjected to a step of heating, for example a step of baking the tray containing the components, in order to remove moisture during the manufacturing process of the components. Therefore, materials for trays are required to have physical properties such as heat resistance, stability and low distortion before and after baking, electrostatic dispersion, surface resistance, electrical conductivity, and low sloughing.

[0004] Conventionally, to satisfy the above properties, a material comprising carbon fiber or carbon black has been used.

[0005] However, in case that carbon fiber or carbon black is included, there is a limit in improving moldability and low sloughing characteristics. Specifically, the content of the carbon filler is high, so that the moldability is poor and the carbon comes out.

[0006] Therefore, research is needed to provide an optimal composition for simultaneously improving physical properties such as strength, low sloughing, surface resistance, and electrostatic dispersion for an antistatic composite material.

[0007] CN 101759987 A relates to a polycarbonate blend comprising polystyrene and copolymers of styrene, acrylonitrile and butadiene. The composition includes 0.3 to 5.0% carbon nanotubes.

[0008] JP 2009074072 A discloses a thermoplastic resin composition comprising carbon nanotubes to improve the perculation. The polymer resin may include polystyrene and acrylonitrile-butadiene-styrene copolymer. The carbon nanotubes are said to be single- or multi-walled.

[0009] KR 20100127953 A discloses a thermoplastic rubber with conductive fillers. ABS and PS are mentioned as rubber components. Carbon fibers and carbon nanotubes are disclosed as conductive fillers.

SUMMARY OF THE INVENTION



[0010] An object of the present invention is to provide an antistatic carbon composite material.

[0011] Other object of the present invention is to provide a molded product comprising the carbon composite material.

[0012] Another object of the present invention is to provide a method for manufacturing the molded product.

[0013] In order to solve the above-described problems, the present invention provides an antistatic carbon composite material, comprising:

a thermoplastic resin; and

0.1 to 10 wt% of carbon nanotubes based on the total weight of the thermoplastic resin;

wherein the thermoplastic resin comprises acrylonitrile-butadiene-styrene copolymer and polystyrene,

wherein the content ratio of the acrylonitrile-butadiene-styrene copolymer to the polystyrene is from 1: 9 to 8: 2, and

wherein the carbon nanotube is in the form of a rigid random coil.



[0014] The carbon nanotube may have an average particle diameter of 5 nm to 50 nm and an average length of 10 µm to 100 µm.

[0015] According to one embodiment, the content of the carbon nanotube may be 0.5 to 3 wt%.

[0016] The carbon nanotube may be a single-walled nanotube, a multi-walled nanotube, or mixture thereof.

[0017] The thermoplastic resin may further comprise at least one or more selected from the group consisting of a polycarbonate resin, a polypropylene resin, a polyamide resin, an aramid resin, an aromatic polyester resin, a polyolefin resin, a polyester carbonate resin, a polyphenylene ether resin, a polyphenylene sulfide resin, a polysulfone resin, a polyether sulfone resin, a polyarylene resin, a cycloolefin resin, a polyetherimide resin, a polyacetal resin, a polyvinyl acetal resin, a polyketone resin, a polyether ketone resin, a polyether ether ketone resin, a polyaryl ketone resin, a polyether nitrile resin, a liquid crystal resin, a polybenzimidazole resin, a polyparabanic acid resin, a vinyl-based polymer or copolymer resin obtained by polymerizing or copolymerizing at least one vinyl monomers selected from the group consisting of an aromatic alkenyl compound, methacrylic acid ester, acrylic acid ester and a vinyl cyanide compound, a diene-aromatic alkenyl compound copolymer resin, a vinyl cyanide-diene-aromatic alkenyl compound copolymer resin, an aromatic alkenyl compound-diene-vinyl cyanide-N-phenyl maleimide copolymer resin, a vinyl cyanide-(ethylene-diene-propylene(EPDM))-aromatic alkenyl compound copolymer resin, a vinyl chloride resin, a chlorinated vinyl chloride resin.

[0018] According to one embodiment, the carbon composite material may further comprise one or more selected from the group consisting of an antimicrobial agent, a releasing agent, a heat stabilizer, an antioxidant, a light stabilizer, a compatibilizer, a dye, an inorganic additive, a surfactant, a nucleating agent, a coupling agent, a filler, a plasticizer, an impact modifier, an admixture, a coloring agent, a lubricant, an antistatic agent, a pigment, a flame retardant agent, and a mixture of one or more of the foregoing.

[0019] According to one embodiment, the carbon composite material may have a percolation threshold of 2 to 60 wt% when the carbon nanotubes are added to the thermoplastic resin.

[0020] According to another embodiment, the carbon composite material may include an additional conductive filler having a difference in percolation threshold value from 10 to 50 wt% with respect to the carbon nanotubes.

[0021] Furthermore, according to the embodiment of the present invention, an antistatic molded product obtained by extruding, injection molding, or a combination thereof of the composite material can be provided.

[0022] The molded product may be a transfer cart for electronic components, a coating material of transfer pipe for electronic components, and a thermoforming tray for electronic components.

[0023] The impact strength of the molded product may be 7 g · cm / cm or more.

[0024] The abrasion resistance of the molded product may be 1% or less.

[0025] In addition, according to the present invention, there is provided a method for manufacturing antistatic molded product comprising the steps of:

mixing 0.1 to 10 wt% of carbon nanotubes with thermoplastic resin containing acrylonitrile-butadiene-styrene copolymer and polystyrene; and

producing an antistatic molded product by extruding, injection, or a combination thereof,

wherein the content ratio of the acrylonitrile-butadiene-styrene copolymer to the polystyrene is from 1: 9 to 8: 2.



[0026] Other specific embodiments of the present invention are included in the following detailed description.

Effect of the invention



[0027] According to the antistatic carbon composite material, the molded product and the method of manufacturing the same according to the present invention, it is possible to simultaneously improve physical properties such as strength, low-sloughing, surface resistance and electrostatic dispersion, so that the present invention can be applied to products requiring strength and electric conductivity.

BRIEF DESCRIPTION OF THE DRAWINGS



[0028] 

Fig. 1 is a photograph showing a result of the abrasion rate evaluation.

Fig. 2 is a graph showing electrostatic dispersion characteristic.


DETAILED DESCRIPTION OF THE INVENTION



[0029] As used herein, the term "composite" may be used interchangeably with "composite material" and "complex" and may be understood to mean a material formed by combining two or more materials.

[0030] In addition, the term "molded product" in this specification may be used interchangeably with "processed product" and may be understood as a product formed in a desired shape by applying heat or pressure.

[0031] Hereinafter, an antistatic carbon composite material, a molded product and a method of manufacturing the same according to embodiments of the present invention will be described in detail.

[0032] The antistatic carbon composite material according to the present invention comprises:

a thermoplastic resin; and

0.1 to 10 wt% of carbon nanotubes based on the total weight of the thermoplastic resin;

wherein the thermoplastic resin comprises acrylonitrile-butadiene-styrene copolymer and polystyrene,

wherein the content ratio of the acrylonitrile-butadiene-styrene copolymer to the polystyrene is from 1: 9 to 8: 2, and

wherein the carbon nanotube is in the form of a rigid random coil.



[0033] The carbon composite material includes acrylonitrile-butadiene-styrene copolymer and polystyrene as thermoplastic resin, thereby improving physical properties such as moldability and improving low sloughing.

[0034] The content ratio of the acrylonitrile-butadiene-styrene copolymer to the polystyrene is 1: 9 to 8: 2, for example, 1 to 3: 5 to 9. In the present invention, the thermoplastic resin comprises the acrylonitrile-butadiene-styrene copolymer and the polystyrene and the content ratio thereof is set as described above, whereby the physical properties such as strength, low sloughing, surface resistance and electrostatic dispersion can be simultaneously improved.

[0035] According to one embodiment, the average particle size of the carbon nanotube may be from 5 nm to 50 nm, for example, from 5 nm to 30 nm. If the particle size is small, the rate of increase of the thermal conductivity can be increased. On the other hand, if the particle size is large, the dispersibility deteriorates and the moldability can be affected.

[0036] The maximum diameter of the carbon material may be 50 nm. When the carbon material having the maximum diameter is included, it may be included not more than 10 parts by weight based on the total weight of the carbon material, for example 5 parts by weight or less.

[0037] According to one embodiment, the average length of the carbon nanotube may be 10 µm to 100 µm. If the average particle diameter or the average length are smaller than the above range, the strength and the moldability may be reduced, and if the average particle diameter and the average length are larger than the above range, the thermal conductivity may increase.

[0038] The maximum length of the carbon nanotube may be 100 µm. When the carbon nanotube having the maximum length is included, it may be included not exceeding 20 parts by weight based on the total weight of the carbon nanotube, for example 10 parts by weight or less.

[0039] According to one embodiment, the content of the carbon nanotube may be 0.5 to 3 wt%, for example, 1 to 2 wt%. When the content of the carbon nanotube is smaller the above range, the electrical conductivity and the strength may not be sufficiently improved. On the other hand, when the content of the carbon nanotube is excessive, the moldability may be deteriorated.

[0040] The carbon nanotube is in the form of a rigid random coil. The carbon nanotube in the form of a rigid random coil can be defined as carbon nanotube that do not undergo elastic deformation caused by thermal energy (kT, where k is the Boltzmann constant and T is the absolute temperature) within the contour length of the used particles because their effective bending modulus is greater than the thermal energy and whose overall particle size (end-to-end distance) is linearly proportional to the square root of the apparent molecular weight.

[0041] The carbon nanotube may be a single-walled nanotube, a multi-walled nanotube, or mixtures thereof. For example, only single-walled carbon nanotube may be used, or a combination of single-walled nanotube and multi-walled nanotube may be used. Specifically, the ratio of the single-walled carbon nanotube to the multi-walled carbon nanotube may be 0: 100 to 100: 0, for example, 10:90 to 90:10.

[0042] According to one embodiment, the thermoplastic resin may further comprise at least one selected from the group consisting of but not limited to a polycarbonate resin, a polypropylene resin, a polyamide resin, an aramid resin, an aromatic polyester resin, a polyolefin resin, a polyester carbonate resin, a polyphenylene ether resin, a polyphenylene sulfide resin, a polysulfone resin, a polyether sulfone resin, a polyarylene resin, a cycloolefin resin, a polyetherimide resin, a polyacetal resin, a polyvinyl acetal resin, a polyketone resin, a polyether ketone resin, a polyether ether ketone resin, a polyaryl ketone resin, a polyether nitrile resin, a liquid crystal resin, a polybenzimidazole resin, a polyparabanic acid resin, a vinyl-based polymer or copolymer resin obtained by polymerizing or copolymerizing at least one vinyl monomers selected from the group consisting of an aromatic alkenyl compound, methacrylic acid ester, acrylic acid ester and a vinyl cyanide compound, a diene-aromatic alkenyl compound copolymer resin, a vinyl cyanide-diene-aromatic alkenyl compound copolymer resin, an aromatic alkenyl compound-diene-vinyl cyanide-N-phenyl maleimide copolymer resin, a vinyl cyanide-(ethylene-diene-propylene(EPDM))-aromatic alkenyl compound copolymer resin, polyolefin, a vinyl chloride resin and a chlorinated vinyl chloride resin, and may further include a thermoplastic resin suitably selected by those skilled in the art.

[0043] The polyolefin resin may be, for example, polypropylene, polyethylene, polybutylene, and poly(4-methyl-1-pentene), or a combination thereof, but is not limited thereto. In one embodiment, examples of the polyolefin include polypropylene homopolymer (e.g., atactic polypropylene, isotactic polypropylene, and syndiotactic polypropylene), polypropylene copolymer (e.g., polypropylene random copolymer), and mixtures thereof. Suitable polypropylene copolymer includes, but is not limited to, random copolymer prepared by the polymerization of propylene in the presence of comonomers selected from the group consisting of ethylene, but-1-ene (i.e., 1-butene), and hex-1-ene (i.e., 1-hexene). In the polypropylene random copolymer, the comonomers may be present in any suitable amount, but are typically present in an amount of about 10 wt% or less (e.g., from about 1 to about 7 wt%, or from about 1 to about 4.5 wt%).

[0044] The polyester resin refers to a homopolyester or copolymer polyester which is a polycondensate of a dicarboxylic acid component skeleton and a diol component skeleton. Representative examples of the homopolyester include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, poly-1,4-cyclohexanedimethylene terephthalate, and polyethylene diphenylate. Particularly, polyethylene terephthalate is preferable because it can be used in many applications due to its low price. The copolyester is defined as a polycondensate of at least three components selected from components having a dicarboxylic acid skeleton and components having a diol skeleton, as exemplified below. Examples of the components having a dicarboxylic acid skeleton include terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalene dicarboxylic acid, 1,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 4,4'-diphenyl dicarboxylic acid, 4,4'-diphenylsulfone dicarboxylic acid, adipic acid, sebacic acid, dimeric acid, cyclohexane dicarboxylic acid and ester derivatives thereof. Examples of the components having a glycol skeleton include ethylene glycol, 1,2-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, diethylene glycol, polyalkylene glycol, 2,2-bis(4'-β-hydroxyethoxyphenyl)propane, isosorbate, 1,4-cyclohexanedimethanol, and spiroglycol.

[0045] As the polyamide resin, a nylon resin, a nylon copolymer resin, and mixtures thereof can be used. The nylon resin may be polyamide-6 (nylon 6) obtained by ring-opening polymerization of commonly known lactams such as ε-caprolactam or ω-dodecaractam; nylon polymerization products obtainable from amino acids such as aminocaproic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid; nylon polymers obtainable by polymerization of an aliphatic, alicyclic or aromatic diamine such as ethylenediamine, tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 5-methylnonahexamethylenediamine, meta-xylenediamine, para-xylenediamine, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethyl cyclohexane, bis(4-aminocyclohexyl)methane, bis(4-methylcyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane, bis(aminopropyl)piperazine or aminoethylpiperidine, with an aliphatic, alicyclic or aromatic dicarboxylic acid such as adipic acid, sebacic acid, azelaic acid, terephthalic acid, 2-chloroterephthalic acid and 2-methylterephthalic acid; and copolymers or mixtures thereof. Examples of the nylon copolymer includes copolymer of polycaprolactam (nylon 6) and polyhexamethylene sebacamide (nylon 6,10), copolymer of polycaprolactam (nylon 6) and polyhexamethylene adipamide (nylon 66), copolymer of polycaprolactam (nylon 6) and polylauryllactam (nylon 12).

[0046] The polycarbonate resin may be prepared by reacting a diphenol with phosgene, a halogen formate, a carbonic ester, or a combination thereof. Specific examples of the diphenol include hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, 2,2-bis(4-hydroxyphenyl)propane (also referred to as 'bisphenol-A'), 2,4-bis(4-hydroxyphenyl)-2-methylbutane, bis(4-hydroxyphenyl)methane, 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-hyroxyphenyl)propane, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)ketone, and bis(4-hydroxyphenyl)ether. Of these, for example, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4-hyroxyphenyl)propane or 1,1-bis(4-hydroxyphenyl)cyclohexane can be used, and for example 2,2-bis(4-hyroxyphenyl)propane can be used.

[0047] The polycarbonate resin may comprise a mixture of copolymers prepared from two or more diphenols. As the polycarbonate resin, there may be used, for exemple a linear polycarbonate resin, a branched polycarbonate resin, or a polyester carbonate copolymer resin.

[0048] Examples of the linear polycarbonate resin include a bisphenol-A type polycarbonate resin. Examples of the branched polycarbonate resin include those prepared by reacting a polyfunctional aromatic compound such as trimellitic anhydride, and trimellitic acid with a diphenol and a carbonate. The polyfunctional aromatic compound may be contained in an amount of 0.05 to 2 mol% based on the total amount of the branched polycarbonate resin. Examples of the polyester carbonate copolymer resin include those prepared by reacting a difunctional carboxylic acid with a diphenol and a carbonate. As the carbonate, there may be used, for example diaryl carbonate such as diphenyl carbonate, and ethylene carbonate.

[0049] As the cycloolefin-based polymer, there may be exemplified ethylene-cycloolefin copolymers available under the trade name "Apel" (Mitsui Chemicals), norbornene-based polymers available under the trade name "Aton" (JSR), and norbornene-based polymers available under the trade name "Zeonoa" (Nippon Zeon).

[0050] According to one embodiment, among the polymer resins, at least one selected from polycarbonate, polyacrylonitrile-butadiene-styrene, polyester carbonate, polypropylene and polyolefin may be used. For example, at least one selected the group consisting of a polyethylene resin, a polyamide resin, a polyester resin, a polycarbonate resin, a polyarylate resin, and a cyclopolyolefin resin can be used.

[0051] According to one embodiment, dielectric properties can be effectively controlled by setting the weight ratio of the carbon nanotube and the thermoplastic resin to 1:10 to 1000, for example, 1:10 to 100, for example, 1:50 to 100.

[0052] According to one embodiment, the carbon composite material may have a percolation threshold of 2 to 60 wt% when the carbon nanotubes are added to the thermoplastic resin. Here, the "threshold value of percolation" is used to indicate the content (% by weight) of the conductive filler when the volume resistivity of the resin is thoroughly changed from the insulating region to the conductive region by adding the conductive filler to the resin.

[0053] The carbon nanotube may include two or more of different carbon nanotubes having a difference in percolation threshold value within a range of 10 to 50 wt%.

[0054] According to another embodiment, the carbon composite material may further include an additional conductive filler having a difference in percolation threshold value from 10 to 50 wt% with respect to the carbon nanotubes.

[0055] The conductive filler may be fine graphitized fibers having a fiber diameter of 3.5 to 120 nm, fine graphite fibers having a fiber diameter of 120 to 500 nm, carbon fibers having a fiber diameter of 3 to 12 µm, or carbon particles having a diameter of 1 to 500 µm.

[0056] Further, when the total amount of the conductive filler in the resin is in the range of 10 to 20 mass%, the change in the volume resistivity of the resin composite may be in a range of 10X±1 Ωcm (2≤X≤11).

[0057] According to one embodiment, the carbon composite material according to the present invention may further comprise at least one additive selected from the group consisting of an antimicrobial agent, a releasing agent, a heat stabilizer, an antioxidant, a light stabilizer, a compatibilizer, a dye, an inorganic additive, a surfactant, a nucleating agent, a coupling agent, a filler, a plasticizer, an impact modifier, an admixture, a coloring agent, a lubricant, an antistatic agent, a pigment, a flame retardant agent, and a mixture of one or more of the foregoing.

[0058] Such an additive may be included within a range that does not affect the physical properties such as impact strength and electromagnetic wave shielding performance of the composite and the molded product according to the present invention, and may be included in an amount of 0.1 to 5 parts by weight, for example 0.1 to 3 parts by weight based on 100 parts by weight of the polymer resin.

[0059] The antistatic carbon composite material of the present invention can be applied to an antistatic product which requires strength and electric conductivity by forming a molded product by extrusion, injection or extrusion and injection. However, a method for producing the molded product can be suitably used as long as it is a conventional method used in the art, and is not limited to the above description.

[0060] Specifically, according to the present invention, there may be provided a method for manufacturing antistatic molded product comprising the steps of:

mixing 0.1 to 10 wt% of carbon nanotubes with thermoplastic resin containing acrylonitrile-butadiene-styrene copolymer and polystyrene; and

producing an antistatic molded product by extruding, injection, or a combination thereof,

wherein the content ratio of the acrylonitrile-butadiene-styrene copolymer to the polystyrene is from 1: 9 to 8: 2.



[0061] Examples of the molded product that can be formed by the above-described method include, but are not limited to, a transfer cart for electronic components, a coating material of transfer pipe for electronic components, and a thermoforming tray for electronic components.

[0062] According to one embodiment, the molded product may, for example, have impact strength of 7 g · cm/cm or more and abrasion resistance of 1% or less. The impact strength may be defined as Izod impact strength, and may be measured by an experimental method according to the specification of ASTM D256.

[0063] The present invention will be explained in more detail with reference to the following examples, including comparative examples. However, these examples are provided for illustrative purposes only and are not intended to limit the scope of the invention.

[0064] Examples 1 to 3 and Comparative examples 1 to 3: Manufacturing of carbon composite material

[0065] The carbon material under the conditions shown in Table 1 was used to prepare respective carbon composite material.

[0066] As the carbon nanotube, a multi-wall carbon nanotube Nanocyl NC7000 having an average particle diameter of 10 nm and an average length of 1 µm was used.

[0067] As the carbon black, KETJENBLACK EC-600JD (trade name, manufactured by Lion Akzo Co., Ltd.) was used.

[0068] As the carbon fiber, HTA-CMF-0160-OH (hereinafter, also referred to as CF1; trade name, manufactured by TOHO TENAX Co., Ltd.) and HTA-CMF-0040-OH (hereinafter, also referred to as CF2; trade name, manufactured by TOHO TENAX Co., Ltd.) were used.
[Table 1]
 Thermoplastic resinContent ratio of thermoplastic resinCarbon materialContent of carbon material (wt%)Percolation threshold (%)
Example 1 ABS, polystyrene 2:8 Carbon nanotube 1.0 3
Example 2 ABS, polystyrene 2:8 Carbon nanotube 1.5 2.5
Example 3 ABS, polystyrene 2:8 Carbon nanotube 2.0 2
Comparative example 1 ABS, polystyrene 2:8 Carbon black 8 7
Comparative example 2 ABS, polystyrene 2:8 Carbon black 10 7
Comparative example 3 ABS, polystyrene 2:8 Carbon black 12 6
Example 4 ABS, polystyrene 2:8 Carbon nanotube / Carbon fiber CF1 1.5/5 3/18
Example 5 ABS, polystyrene 2:8 Carbon nanotube / Carbon fiber 3/5 3/50
      CF2    
ABS: Acrylonitrile-Butadiene-Styrene copolymer

[Evaluation method of percolation threshold]



[0069] Labo Plastomill (trade name, manufactured by Toyo Seiki Seisaku-sho, LTD.) was used for kneading. First, the resin was introduced into the mill. When the resin was melted, carbon nanotube and/or conductive filler were introduced. The kneading was performed under the condition that the resin temperature was 280 °C, the mixer rotation speed was 80 rpm, and the kneading time was 10 minutes. The kneaded sample was molded into a flat plate having a size of 100 x 100 x 2 mm by melt pressing and its volume resistivity value was measured. The content (% by weight) of the carbon filler that characterizes a dramatic change in volume resistivity from the insulating region to the current conducting region is regarded as percolation threshold.

[0070] The resistance value was determined as follows: A silver paste having a resistance lower than that of carbon filler is used. The carbon filler is added to the silver paste to increase the content thereof in the silver paste. The resistance value is estimated based on 100% carbon filler.

[0071] The volume resistivity of the molded product was measured by means of an insulation resistance meter (high resistance meter, trade name: R8340, manufactured by ADVANTEST CORPORATION) on a molded product having a volume resistivity of 108 Ωm or more. A 4-probe method (trade name: Loresta HP MCP-T410, manufactured by Mitsubishi Chemical corporation) was used for a molded product having a volume resistivity of 108 Ωm or less.

Preparation Example 1: Production of specimen of molded product



[0072] Each carbon composite material in Table 1 was extruded from a twinscrew extruder (L/D=42, ϕ=40mm) while raising the temperature profile up to 280 °C to obtain a pellet having a size of 0.2 mm x 0.3 mm x 0.4 mm.

[0073] The prepared pellets were injected in an injector under a flat profile condition of injection temperature 280 °C to prepare specimen of 3.2 mm in size, 12.7 mm in length and in dog-bone form.

Experimental Example 1: Measurement of surface resistance according to thickness



[0074] The specimen was prepared in the same manner as in Preparation Example 1, except that the thickness of the specimen was changed as shown in Table 2, and the surface resistivity was measured.

[0075] The surface resistance value was measured by the method according to the IEC60093 standard, and is shown in Table 2 below. The number means an exponent of base 10, and the unit is (ohm/sq). In the following Table 2, T denotes the sheet thickness, which is expressed in mm, and X means that the measurement range is exceeded.
[Table 2]
  1.0T 0.7T 0.5T 0.3T 0.2T
Example 18∼X11∼XXXX
Example 2 5∼6 6∼7 8∼9 9∼12 X
Example 3 4∼5 4∼5 5 6∼7 7∼8
Comparative Example 1 7∼X 7∼X 8∼X 10∼X X
Comparative Example 2 5∼6 5∼6 6 8∼9 X
Comparative Example 3 4 4 4 4∼5 5∼6

Experimental Example 2: Measurement of Impact strength



[0076] Using the specimen according to Preparation Example 1, the Izod impact strength was measured according to the ASTM D256 standard.

[0077] The impact strength values of the specimens according to Example 3 and Comparative Example 2 were measured and the results are shown in Table 3 below.
[Table 3]
 Measurement conditionImpact strength (kg·cm/cm)
Example 3 1/8"@ 23°C, notched 9
Comparative Example 2 1/8"@ 23°C, notched 3

Experimental Example 3: Evaluation of Abrasion resistance



[0078] Using the specimen according to Preparation Example 1, the abrasion resistance was evaluated by the method according to the ASTM F510 standard.

[0079] The abrasion resistance values of the specimens according to Example 3 and Comparative Example 2 were measured and the results are shown in Table 4 below.
[Table 4]
 RunAbrasion resistance (%)Average
Example 2 1 0.64 0.65
2 0.71
3 0.59
Comparative Example 2 1 1.40 1.35
2 1.34
3 1.32


[0080] In addition, with respect to abrasion resistance, rubbing evaluation was performed for Example 3 and Comparative Example 2.

[0081] The rubbing evaluation was carried out by rubbing the specimen 5 times on a white paper, and the results thereof are shown in Fig 1. From the results shown in Fig. 1, it can be seen that the specimen according to the Example is stronger than the specimen according to the comparative example in terms of the drop-off characteristics of the particles due to abrasion.

Experimental Example 4: Evaluation of electrostatic dispersion of carbon nanotube



[0082] The electrostatic dispersion characteristics of carbon black and carbon nanotube were measured by a triboelectric measuring method and the results are shown in Fig. 2.

[0083] From the results shown in Fig. 2, it can be seen that the composite material according to the present invention has a tribocharge of at least 10 times lower at the same surface resistance, thereby exhibiting excellent electrostatic dispersion characteristics.

[0084] While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that such detailed descriptions are merely preferred embodiments and the scope of the present invention is not limited thereto. Therefore, the true scope of the present invention should be defined by the appended claims and their equivalents.


Claims

1. An antistatic carbon composite material, comprising: a thermoplastic resin; and
0.1 to 10 wt% of carbon nanotubes based on the total weight of the thermoplastic resin;
wherein the thermoplastic resin comprises acrylonitrile-butadiene-styrene copolymer and polystyrene,
wherein the content ratio of the acrylonitrile-butadiene-styrene copolymer to the polystyrene is from 1: 9 to 8: 2, and
wherein the carbon nanotube is in the form of a rigid random coil.
 
2. The antistatic carbon composite material according to claim 1, wherein the carbon nanotube has an average particle diameter of 5 nm to 50 nm and an average length of 10 µm to 100 µm.
 
3. The antistatic carbon composite material according to claim 1, wherein the content of the carbon nanotube is 0.5 to 3 wt%.
 
4. The antistatic carbon composite material according to claim 1, wherein the carbon nanotube is a single-walled nanotube, a multi-walled nanotube, or a combination thereof.
 
5. The antistatic carbon composite material according to claim 1, wherein the thermoplastic resin further comprises at least one selected from the group consisting of a polycarbonate resin, a polypropylene resin, a polyamide resin, an aramid resin, an aromatic polyester resin, a polyolefm resin, a polyester carbonate resin, a polyphenylene ether resin, a polyphenylene sulfide resin, a polysulfone resin, a polyether sulfone resin, a polyarylene resin, a cycloolefin resin, a polyetherimide resin, a polyacetal resin, a polyvinyl acetal resin, a polyketone resin, a polyether ketone resin, a polyether ether ketone resin, a polyaryl ketone resin, a polyether nitrile resin, a liquid crystal resin, a polybenzimidazole resin, a polyparabanic acid resin, a vinyl-based polymer or copolymer resin obtained by polymerizing or copolymerizing at least one vinyl monomers selected from the group consisting of an aromatic alkenyl compound, methacrylic acid ester, acrylic acid ester and a vinyl cyanide compound, a diene-aromatic alkenyl compound copolymer resin, a vinyl cyanide-diene-aromatic alkenyl compound copolymer resin, an aromatic alkenyl compound-diene-vinyl cyanide-N-phenyl maleimide copolymer resin, a vinyl cyanide-(ethylene-diene-propylene(EPDM))-aromatic alkenyl compound copolymer resin, a vinyl chloride resin and a chlorinated vinyl chloride resin.
 
6. The antistatic carbon composite material according to claim 1, wherein the carbon composite material further comprises at least one additive selected from the group consisting of an antimicrobial agent, a releasing agent, a heat stabilizer, an antioxidant, a light stabilizer, a compatibilizer, a dye, an inorganic additive, a surfactant, a nucleating agent, a coupling agent, a filler, a plasticizer, an impact modifier, an admixture, a coloring agent, a stabilizer, a lubricant, an antistatic agent, a pigment, a flame retardant agent, and a mixture of one or more of the foregoing.
 
7. The antistatic carbon composite material according to claim 1, wherein the carbon composite material has a percolation threshold of 2 to 60 wt% when the carbon nanotubes are added to the thermoplastic resin, wherein the percolation threshold is measured as disclosed in the specification.
 
8. The antistatic carbon composite material according to claim 7, wherein the carbon composite material further comprises an additional conductive filler having a difference in percolation threshold value from 10 to 50 wt% with respect to the carbon nanotubes, wherein the percolation threshold is measured as disclosed in the specification.
 
9. An antistatic molded product obtained by extrusion, injection, or a combination thereof of the antistatic carbon composite material according to anyone of claims 1 to 8.
 
10. The antistatic molded product according to claim 9, wherein the molded product is a transfer cart for electronic components, a coating material of transfer pipe for electronic components, or a thermoforming tray for electronic components.
 
11. The antistatic molded product according to claim 9, wherein the impact strength of the molded product is 7 g · cm / cm or more, wherein the impact strength is measured according to ASTM D256 standard.
 
12. The antistatic molded product according to claim 9, wherein the abrasion resistance of the molded product is 1% or less, wherein the abrasion resistance is measured according to ASTM F510 standard.
 
13. A method for manufacturing antistatic molded product comprising the steps of:
mixing 0.1 to 10 wt% of carbon nanotubes with thermoplastic resin containing acrylonitrile-butadiene-styrene copolymer and polystyrene; and producing an antistatic molded product by extruding, injection, or a combination thereof, wherein the content
ratio of the acrylonitrile-butadiene-styrene copolymer to the polystyrene is from 1:9 to 8:2.
 


Ansprüche

1. Antistatisches Kohlenstoffverbundmaterial, umfassend:

ein thermoplastisches Harz; und
0,1 bis 10 Gewichtsprozent Kohlenstoffnanoröhrchen, basierend auf dem Gesamtgewicht des thermoplastischen Harzes;

wobei das thermoplastische Harz Acrylnitril-Butadien-Styrol-Copolymer und Polystyrol umfasst,

wobei das Gehaltsverhältnis des Acrylnitril-Butadien-Styrol-Copolymers zum Polystyrol 1:9 bis 8:2 ist, und

wobei das Kohlenstoffnanoröhrchen in der Form einer starren Zufallsspule ist.


 
2. Antistatisches Kohlenstoffverbundmaterial nach Anspruch 1, wobei das Kohlenstoffnanoröhrchen einen durchschnittlichen Teilchendurchmesser von 5 nm bis 50 nm und eine durchschnittliche Länge von 10 µm bis 100 µm aufweist.
 
3. Antistatisches Kohlenstoffverbundmaterial nach Anspruch 1, wobei der Gehalt des Kohlenstoffnanoröhrchens 0,5 bis 3 Gewichtsprozent ist.
 
4. Antistatisches Kohlenstoffverbundmaterial nach Anspruch 1, wobei das Kohlenstoffnanoröhrchen ein einwandiges Nanoröhrchen, ein mehrwandiges Nanoröhrchen oder eine Kombination derselben ist.
 
5. Antistatisches Kohlenstoffverbundmaterial nach Anspruch 1, wobei das thermoplastische Harz ferner wenigstens eines umfasst, ausgewählt aus der Gruppe bestehend aus einem Polycarbonatharz, einem Polypropylenharz, einem Polyamidharz, einem Aramidharz, einem aromatischen Polyesterharz, einem Polyolefinharz, einem Polyestercarbonatharz, einem Polyphenylenetherharz, einem Polyphenylensulfidharz, einem Polysulfonharz, einem Polyethersulfonharz, einem Polyarylenharz, einem Cycloolefinharz, einem Polyetherimidharz, einem Polyacetalharz, einem Polyvinylacetalharz, einem Polyketonharz, einem Polyetherketonharz, einem Polyetheretherketonharz, einem Polyarylketonharz, einem Polyethernitrilharz, einem Flüssigkristallharz, einem Polybenzimidazolharz, einem Polyparabansäureharz, einem Polymer- oder Copolymerharz auf Vinylbasis, erhalten durch Polymerisieren oder Copolymerisieren wenigstens eines Vinylmonomers, das ausgewählt ist aus der Gruppe, bestehend aus einer aromatischen Alkenylverbindung, Methacrylsäureester, Acrylsäureester und einer Vinylcyanidverbindung, einem Dien-aromatische Alkenylverbindung-Copolymerharz, einem Vinylcyanid-Dien-aromatische Alkenylverbindung-Copolymerharz, einem aromatische Alkenylverbidnung-Dien-Vinylcyanid-N-Phenylmaleimid-Copolymerharz, einem Vinylcyaid-(Ethylen-Dien-Propylen(EPDM))-aromatische Alkenylverbindung-Copolymerharz, einem Vinylchloridharz und einem chlorierten Vinylchloridharz.
 
6. Antistatisches Kohlenstoffverbundmaterial nach Anspruch 1, wobei das Kohlenstoffverbundmaterial ferner wenigstens ein Additiv umfasst, das ausgewählt ist aus der Gruppe bestehend aus einem antimikrobiellen Agens, einem Trennmittel, einem Wärmestabilisator, einem Antioxidationsmittel, einem Lichtstabilisator, einem Kompatibilisator, einem Farbstoff, einem anorganischen Additiv, einem Tensid, einem Nukleierungsmittel, einem Kopplungsmittel, einem Füllstoff, einem Weichmacher, einem Schlagzähmodifizierer, einer Beimsichung, einem Färbemittel, einem Stabilisator, einem Gleitmittel, einem antistatischen Mittel, einem Pigment, einem Flammhemmstoff und einer Mischung aus einem oder mehreren der vorangehenden.
 
7. Antistatisches Kohlenstoffverbundmaterial nach Anspruch 1, wobei das Kohlenstoffverbundmaterial einen Perkolationsgrenzwert von 2 bis 60 Gewichtsprozent aufweist, wenn die Kohlenstoffnanoröhrchen zu dem thermoplastischen Harz zugegeben werden, wobei der Perkolationsgrenzwert wie in der Beschreibung offenbart gemessen wird.
 
8. Antistatisches Kohlenstoffverbundmaterial nach Anspruch 7, wobei das Kohlenstoffverbundmaterial ferner einen zusätzlichen leitfähigen Füllstoff mit einem Unterschied im Perkolationsgrenzwert von 10 bis 50 Gewichtsprozent in Bezug auf die Kohlenstoffnanoröhrchen aufweist, wobei der Perkolationsgrenzwert wie in der Beschreibung offenbart gemessen wird.
 
9. Antistatisches Formprodukt, erhältlich durch Extrusion, Injektion oder eine Kombination derselben des antistatischen Kohlenstoffverbundmaterials nach einem der Ansprüche 1 bis 8.
 
10. Antistatisches Formprodukt nach Anspruch 9, wobei das Formprodukt ein Umsetzungswagen für elektronische Komponenten, ein Beschichtungsmaterial eines Umsetzungsrohres für elektronische Komponenten oder ein Thermoverformungstablett für elektronische Komponenten ist.
 
11. Antistatisches Formprodukt nach Anspruch 9, wobei die Schlagfestigkeit des Formprodukts 7 g•cm/cm oder mehr ist, wobei die Schlagfestigkeit gemäß ASTM D256-Standard gemessen wird.
 
12. Antistatisches Formprodukt nach Anspruch 9, wobei die Abriebfestigkeit des Formprodukts 1% oder weniger ist, wobei die Abriebfestigkeit gemäß ASTM F510-Standard gemessen wird.
 
13. Verfahren zum Herstellen eines antistatischen Formprodukts, umfassend die Schritte:
Mischen von 0,1 bis 10 Gewichtsprozent Kohlenstoffnanoröhrchen mit thermoplastischem Harz, das Acrylnitril-Butadien-Styrol-Copolymer und Polystyrol enthält; und Herstellen eines antistatischen Formprodukts durch Extrudieren, Injektion oder eine Kombination derselben, wobei das Gehaltsverhältnis des Acrylnitril-Butadien-Styrol-Copolymers zum Polystyrol 1:9 bis 8:2 ist.
 


Revendications

1. Matériau en composite carbone antistatique, comprenant : une résine thermoplastique ; et 0,1 à 10 % en poids de nanotubes de carbone par rapport au poids total de la résine thermoplastique ; dans lequel la résine thermoplastique comprend un copolymère acrylonitrile-butadiène-styrène et du polystyrène, dans lequel le rapport du contenu du copolymère acrylonitrile-butadiène-styrène au polystyrène est de 1 : 9 à 8 : 2 , et dans lequel le nanotube de carbone se présente sous la forme d'une bobine aléatoire rigide.
 
2. Matériau en composite carbone antistatique selon la revendication 1, dans lequel le nanotube de carbone a un diamètre moyen de particule de 5 nm à 50 nm et une longueur moyenne de 10 µm à 100 µm.
 
3. Matériau en composite carbone antistatique selon la revendication 1, dans lequel la teneur du nanotube de carbone est de 0,5 à 3 % en poids.
 
4. Matériau en composite carbone antistatique selon la revendication 1, dans lequel le nanotube de carbone est un nanotube à paroi simple, un nanotube à parois multiples ou une combinaison de celles-ci.
 
5. Matériau en composite carbone antistatique selon la revendication 1, dans lequel la résine thermoplastique comprend en outre au moins une résine sélectionnée dans le groupe constitué d'une résine de polycarbonate, d'une résine de polypropylène, d'une résine polyamide, d'une résine aramide, d'une résine polyester aromatique, d'une résine polyoléfine, d'une résine polyester-carbonate, d'une résine polyphénylène-éther, d'une résine polyphénylène-sulfure, d'une résine polysulfone, d'une résine polyéthersulfone, d'une résine polyarylène, d'une résine cyclooléfine, d'une résine polyétherimide, d'une résine polyacétal, d'une résine polyvinylacétal, d'une résine polycétone, d'une résine polyéthercétone, d'une résine polyétheréthercétone, d'une résine polyarylcétone, d'une résine polyéthernitrite, d'une résine de cristal liquide, d'une résine polybenzimidazole, d'une résine d'acide polyparabanique, d'une résine polymère ou copolymère à base de vinyle obtenue par polymérisation ou copolymérisation d'au moins un monomère vinylique sélectionné dans le groupe constitué d'un composé alcényle aromatique, d'un ester d'acide méthacrylique, d'un ester d'acide acrylique et d'un composé de cyanure de vinyle, d'une résine copolymère diène-composé alcényle aromatique, d'une résine copolymère de cyanure de vinyle-diène-composé alcénylique aromatique, d'une résine copolymère de composé alcénylique aromatique-diène-cyanure de vinyle-N-phénylmaléimide, d'une résine de copolymère de cyanure de vinyle-(éthylène-diène-propylène (EPDM))-composé alcénylique aromatique, d'une résine chlorure de vinyle et d'une résine de chlorure de vinyle chloré.
 
6. Matériau en composite carbone antistatique selon la revendication 1, dans lequel le matériau en composite carbone comprend en outre au moins un additif sélectionné dans le groupe constitué d'un agent antimicrobien, d'un agent de libération, d'un stabilisateur thermique, d'un antioxydant, d'un stabilisateur à la lumière, d'un agent de compatibilité, d'un colorant, d'un additif inorganique, d'un agent tensioactif, d'un agent de nucléation, d'un agent de couplage, d'une charge, d'un plastifiant, d'un modificateur d'impact, d'un mélange, d'un colorant, d'un stabilisateur, d'un lubrifiant, d'un agent antistatique, d'un pigment, d'un agent ignifuge et d'un mélange d'un ou de plusieurs des éléments précédents.
 
7. Matériau en composite carbone antistatique selon la revendication 1, le matériau en composite carbone ayant un seuil de percolation de 2 à 60 % en poids lorsque les nanotubes de carbone sont ajoutés à la résine thermoplastique, dans lequel le seuil de percolation est mesuré comme indiqué dans la spécification.
 
8. Matériau en composite carbone antistatique selon la revendication 7, le matériau en composite carbone comprenant en outre une charge conductrice supplémentaire ayant une différence de valeur de seuil de percolation de 10 à 50 % en poids par rapport aux nanotubes de carbone, dans lequel le seuil de percolation est mesuré comme indiqué dans la spécification.
 
9. Produit moulé antistatique obtenu par extrusion, injection ou une combinaison de ces procédés, à partir d'un matériau en composite carbone antistatique selon l'une des revendications 1 à 8.
 
10. Produit moulé antistatique selon la revendication 9, dans lequel le produit moulé est un chariot de transfert pour composants électroniques, un matériau de revêtement de tuyaux de transfert pour composants électroniques, ou un plateau de thermoformage pour composants électroniques.
 
11. Produit moulé antistatique selon la revendication 9, dans lequel la résistance au choc du produit moulé est de 7 g - cm / cm ou supérieure, dans lequel la résistance au choc est mesurée selon la norme D256 de l'ASTM.
 
12. Produit moulé antistatique selon la revendication 9, dans lequel la résistance à l'abrasion du produit moulé est de 1 % ou inférieure, la résistance à l'abrasion étant mesurée selon la norme F510 de l'ASTM.
 
13. Procédé de fabrication d'un produit moulé antistatique comprenant les étapes consistant à : mélanger 0,1 à 10 % en poids de nanotubes de carbone avec une résine thermoplastique contenant un copolymère acrylonitrile-butadiène-styrène et du polystyrène ; et produire un produit moulé antistatique par extrusion, injection, ou une combinaison de ces méthodes, dans lequel le rapport du contenu du copolymère acrylonitrile-butadiène-styrène au polystyrène est de 1 : 9 à 8 : 2.
 




Drawing











Cited references

REFERENCES CITED IN THE DESCRIPTION



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Patent documents cited in the description