• Bulletin of the Korean Chemical Society
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• 제30권6호
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• pp.1337-1340
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• 2009

Electrical properties of a fluorinated carbon black (CB)-filled high-density polyethylene (HDPE) polymeric switch were investigated as a function of fluorination pressure at 0.1 ~ 0.4 MPa. From the FT-IR results, the absorption spectra of the fluorinated CB show an absorption band at 1400 ~ 1000 $cm^{-1}\;for\;{\nu}_{C-F}$ and the peak intensity increased with increasing fluorination pressure. Also, the analysis of XPS spectra of the fluorinated CB indicated that fluorine content increased with increasing fluorination pressure. Meanwhile, the surface free energy of the fluorinated CB decreased with increasing fluorination pressure. Consequently, the increase of fluorine contents of CB made a disappearance of negative temperature coefficient (NTC) behavior of the polymeric switch, which was probably due to the reduction of CB reaggregation after melting point of the HDPE, resulted from the decreasing of London dispersive component of the surface free energy for CB particles.

• Korean Chemical Engineering Research
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• 제46권4호
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• pp.669-675
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• 2008

카본블랙은 토너수지, 잉크 및 복합재료 등에 광범위하게 산업적으로 응용되고 있다. 본 연구에서는 분산 안정성을 증대시키기 위하여 카본블랙을 상 이동 촉매(phase transfer catalyst)를 이용한 상온에서의 산화반응을 통하여 카본블랙(CB)-수산화기(OH)를 제조하여 이에, silane coupling-agent인 p-methylacryloxypropyltrimethoxysilane를 grafting시켜 말단에 이중결합을 가진 구조를 도입하였다. 이렇게 표면개질된 카본블랙을 미니유화중합법을 이용하여 고분자로 캡슐화를 진행하였다. 이러한 과정을 통하여 평균직경 100~500 nm 크기의 하이브리드 미립자를 제조하였다. 중합과정에 있어서 카본블랙의 표면 개질의 영향, 모노머의 종류, 개시제 및 유화제의 캡슐화 반응에 미치는 영향을 연구하였다.

• Carbon letters
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• 제2권3_4호
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• pp.165-169
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• 2001

Modification of C/C composite bipolar plate for improving electrical conductivity was carried out by addition of electroconductive carbon black (EC-CB). Carbon black was carefully mixed to methanol-containing phenolic resin, impregnated into 2D-carbon fabrics, hot pressed and then carbonized to obtain composite plate. Inclusion of electro-conductive carbon black enhanced the electrical conductivity of the C/C composites by increasing the conduction path. Addition of 10 vol% carbon black increased the electrical conductivity from 5.5/${\Omega}cm$ to 32/${\Omega}cm$ and reduced the crack formation by filling effect, resulting in the increase of flexural properties of composite plate. However, at carbon black content over 10 vol%, flexural properties decreased by delaminating role of excess carbon black at the interface in C/C composites.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 추계학술발표대회 논문집
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• pp.71-74
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• 2005

In this paper, the effects of the MWCNTs on the PTC characteristics of the conventional CB/polymer nanocomposites were investigated. For the uniform dispersion of the MWCNTs in the polymer matrix., nitricacid-treated MWCNTs were dispersed with the dissolved HOPE in the solvent. After evaporating solvent, the dried master batches in the oven were melt blended mixed with CB and HDPE to obtain the PTC materials. The initial resistivity of PTC materials decreased and the PTC intensity increased with the MWCNTs. During three repeated heating and cooling cycles, the PTC materials containing MWCNTs showed a great reproducibility due to the conductive network structures of CB particles and MWCNTs.

• Macromolecular Research
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• 제12권1호
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• pp.53-62
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• 2004

We have prepared polymer composites of low-density polyethylene (LDPE) and ionomers (Surlyn 8940) containing polar segments and metal ions by melt blending with carbon black (CB) as a conductive filler. The resistivity and positive temperature coefficient (PTC) of the ionomer/LDPE/CB composites were investigated with respect to the CB content. The ionomer content has an effect on the resistivity and percolation threshold of the polymer composites; the percolation curve exhibits a plateau at low CB content. The PTC intensity of the crosslinked ionomer/LDPE/CB composite decreased slightly at low ionomer content, and increased significantly above a critical concentration of the ionomer. Irradiation-induced crosslinking could increase the PTC intensity and decrease the NTC effect of the polymer composites. The minimum switching current (Ι$\sub$trip/) of the polymer composites decreased with temperature; the ratio of Ι$\sub$trip/ for the ionomer/LDPE/CB composite decreased to a greater extent than that of the LDPE/CB composite. The average temperature coefficient of resistance (${\alpha}$$\sub$T/) for the polymer composites increased in the low-temperature region.

• 대한기계학회논문집A
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• 제34권9호
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• pp.1209-1215
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• 2010

다중벽 탄소나노튜브(MWCNT) 및 카본블랙(CB) 함유량, 대기압 화염 플라즈마(APFP) 처리 그리고 산처리를 함수로 한 고무복합재료의 기계적 특성에 대해 연구하였다. 고무복합재료의 인장강도 및 탄성률은 MWCNT의 함유량 증가에 따라 순수상태 그리고 동일량의 CB가 보강된 상태에 비해 증가하였다. APFP 처리한 MWCNT를 보강한 복합재료는 처리하지 않은 경우에 비해 강화효과(높은 강도, 높은 탄성률 그리고 높은 연성)를 보였다. 반면에 APFP 처리한 CB를 함유한 복합재료는 처리하지 않은 경우에 비해 연화효과(높은 강도, 낮은 탄성률 그리고 높은 연성)를 보였다. 산처리 시간이 1시간에서 2시간으로 증가할수록, 그리고 황산의 농도가 60%에서 90%로 증가할수록 복합재료의 인장강도와 탄성률은 감소하였다. 전체적으로 MWCNT 함유량, CB 함유량, 대기압 화염 플라즈마 처리, 황산 농도 그리고 산처리 시간 등이 고무복합재료의 기계적 특성에 영향을 미치는 중요한 변수임을 확인하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.95.1-95.1
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• 2011

In this work, graphene was prepared by modified Hummers method and prepared graphene was applied to electrode materials for supercapacitor. In addition, to enhance the electrochemical performance of graphene, carbon black was deposited onto graphene via chemical reduction. The effect of the carbon black content incorporated on the electrochemical properties of the graphene-based electrodes was investigated. It was found that nano-scaled carbon black aggregates were deposited and dispersed onto the graphene by the chemical reduction of acid treated carbon black and graphite oxide. From the cyclic voltammograms, carbon black-deposited graphene (CB-GR) showed improved electrochemical performance, i.e., current density, quicker response, and better specific capacitance than that of pristine graphene. This indicates that the carbon black deposited onto graphene served as an conductive materials between graphene layers, leading to reducing the contact resistance of graphene and resulted in the increase of the charge transfer between graphene layers by bridge effect.

• 대한기계학회논문집A
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• 제35권9호
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• pp.999-1005
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• 2011

고무복합재료에 대해 변형에 의한 결정화(SIC)가 기계적 특성에 미치는 영향을 연신율(${\lambda}$) 및 다중벽 탄소나노튜브(CNT)와 카본블랙(CB)의 함유량을 함수로 하여 연구하였다. 시차 주사 열량(DSC) 분석을 통해 CB 및 CNT의 함유량에 따라 결정화 정도가 증가함을 확인 하였다. 또한 연신율이 증가함에 따라 복합재료의 유리전이온도(Tg)는 증가하였고, 결정화 잠열 값(LHc)은 ${\lambda}$=1.5에서 최대값을 보였다. CNT의 함유량 증가에 따라 기계적 특성과 LHc는 비례관계임을 확인하였다. 열 중량 분석(TGA)을 통해 기지의 소실율은 94.3%였고, 복합재료의 소실율은 보강재의 함유량 증가에 따라 감소하였다. 인장탄성율 비는 고무 내의 CNT 배향으로 인장강도 비보다 높게 나타났다.

• Elastomers and Composites
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• 제53권3호
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• pp.175-180
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• 2018

Solution-styrene-butadiene rubber (SSBR) composites were manufactured using four kinds of fillers: silica-silane coated carbon black (SC-CB) hybrid, starch-SC-CB hybrid, pure silica, and pure starch. The influence of filler type on the mechanical properties of the rubber matrix was studied in this work. SC-CB was prepared by silane-graft-coating using vinyl triethoxy silane and carbon black, which enhanced the dispersion effect between the rubber matrix and the filler, and improved the mechanical properties of the compounds. The morphology of the composites was observed by field-emission scanning electron microscopy (FE-SEM). The thermal decomposition behavior of the composites was determined by thermogravimetric analysis (TGA), and the crosslinking behavior of the composites was tested using a rubber process analyzer (RPA). The hardness, tensile strength, swelling ratio, and gas transmittance rate of the composites were evaluated according to ASTM. The test results revealed that with the addition of SC-CB, the hybrid fillers, especially those blended with silica, showed a better reinforcement effect, the highest hardness and tensile strength, and stable thermal decomposition behavior. This implies that the silica-SC-CB hybrid filler has a notable mechanical reinforcement effect on the SSBR matrix. Because of self-crosslinking during its synthesis, the starch-SC-CB hybrid filler produced the most dense matrix, which improved the anti-gas transmittance property. The composites with the hybrid fillers had better anti-swelling properties as compared to the neat SSBR composite, which was due to the hydrophilicity of silica and starch.

• Applied Microscopy
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• 제47권3호
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• pp.121-125
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• 2017

This study deals the prediction of temperature effect on low-frequency dispersion of alternating current (AC) conductivity spectra of composite materials based on copolymer reinforced with carbon black (CB) particles. A sample of ethylene butylacrylate loaded with 13% of CB particles were prepared and investigated using the impedance spectroscopy representation in the frequency range from 40 Hz to 0.1 MHz and temperature range from $20^{\circ}C$ to $125^{\circ}C$. The dielectric constant, ${\varepsilon}^{\prime}$, and dielectric losses, ${\varepsilon}^{{\prime}{\prime}}$, were found to decrease with increasing frequency. The frequency dependence of the AC conductivity follows the universal power law with a large deviation in the high frequency region, the positive temperature coefficient in resistivity effect has been observed below the melting temperature which makes this composite potentially remarkable for industrial applications.