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Carbon letters

Korean Carbon Society (KCS)

  • Quarterly
  • /
  • 1976-4251(pISSN)
  • /
  • 2233-4998(eISSN)

Domain

  • Chemistry ＞ Inorganic Chemistry

Aim & Scope

Carbon Letters aims to be a comprehensive journal with complete coverage of carbon materials and carbon-rich molecules. These materials range from, but are not limited to, diamond and graphite through chars, semicokes, mesophase substances, carbon fibers, carbon nanotubes, graphenes, carbon blacks, activated carbons, pyrolytic carbons, glass-like carbons, etc. Papers on the secondary production of new carbon and composite materials from the above mentioned various carbons are within the scope of the journal. Papers on organic substances, including coals, will be considered only if the research has close relation to the resulting carbon materials. Carbon Letters also seeks to keep abreast of new developments in their specialist fields and to unite in finding alternative energy solutions to current issues such as the greenhouse effect and the depletion of the ozone layer. The renewable energy basics, energy storage and conversion, solar energy, wind energy, water energy, nuclear energy, biomass energy, hydrogen production technology, and other clean energy technologies are also within the scope of the journal. Carbon Letters invites original reports of fundamental research in all branches of the theory and practice of carbon science and technology.

http://carbonlett.org KSCI KCI SCOPUS

Volume 2 Issue 3_4

  1. Park, Soo-Jin;Seo, Min-Kang;Lee, Jae-Rock 159
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    In this study, the effects of carbon black (CB) content and anodic oxidation treatment with $AgNO_3$ on positive temperature coefficient (PTC) behavior of CB/HDPE nanocomposites were investigated. Also, the addition of elastomer as a toughing agent was studied. The 20~50 wt% of CB, 0~5 wtt% of elastomer, and 1 wt% of $AgNO_3$-filled HDPE nanocomposites were prepared using the internal mixer in 60 rpm at $160{\circ}C$ and the compression-molded at $180{\circ}C$ for 10 min. As a result, the room temperature resistivity and PTC intensity of the composites were dependent, to a large extent, on the content of CB, addition of elastomer, and surface chemical properties that were controlled in the relative arrangements of the carbon black aggregates in a polymeric matrix. Moreover, the composites with relatively low room temperature resistivity and suitable PTC intensity could be achieved by treatment of $AgNO_3$. Consequently, it was noted that PTC effect was due to the deagglomeration or the breakage of the conductive networks caused by thermal expansion or crystalline melting of the polymeric matrix.
  2. Ryu, Seung-Kon;Hwang, Taek-Sung;Lee, Seung-Goo;Lee, Sun-A;Kim, Chang-Soo 165
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    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.
  3. Kim, Chan;Lee, Su-Hyun;Kim, Young-Min;Yang, Kap-Seung 170
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    A petroleum-based isotropic pitch fiber spun by melt-blown method was oxidized in air flow at various conditions. The oxidized pitch fiber obtained was tested for its infusibility and its elemental composition during the process of stabilization. The structural changes were traced by using solvent solubility, FT-IR spectroscopy, and elemental analysis. The samples showed a gradual increase in weight with increasing the oxidization temperature. The weight gain of sample oxidized at $320^{\circ}C$ for 10 min was about 4.5%. The concentration of the pyridine and toluene soluble fraction decreased with an increase in stabilization temperatures. The oxygen uptaken in the stabilization process converted aliphatic side chains into the carbonyl groups. As stabilization proceeded, the more ether and carboxylic acid groups were formed through the oxidations of aldehyde and primary alcohol, and then the carboxylic acid was dehydrated to be aromatic anhydride.
  4. Yang, Seung-Chun;Lee, Young-Seak;Kim, Jun-Ho;Lim, Chul-Kyu;Park, Young-Tae 176
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    A series of activated carbons were prepared from coconut shells and coal-tar pitch binder by physical activation with steam in this study. The effect of variable processes such as activation temperature, activation time and ratio of mixing was investigated for optimizing those preparation parameters. The activation processes were carried out continuously. The nitrogen adsorption isotherms at 77 K on pellet-shaped activated carbons show the same trend of Type I by IUPAC classification. The average pore sizes were about 19-21${\AA}$. The specific surface areas ($S_{BET}$) of pellet typed ACs increased with increasing the activation temperature and time. Specific surface area of AC treated for 90 min at temperature $900^{\circ}C$ was 1082 $m^2/g$. The methylene blue numbers continuously increased with increasing the activation temperature and time. On the other hand, iodine numbers highly increased till activation time of 60 min, but the rate of increase of iodine numbers decreased after that time. This indicates that new micropores were created and the existing micropores turned into mesopores and macropores because of increased reactivity of carbon surface and $H_2O$.
  5. Chae, Jae-Hong;Kim, Kyung-Ja;Cho, Kwang-Youn;Choi, Jae-Young 182
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    Quinoline insoluble formed by the heat treatment was hot-pressed near its softening point. The green body was stabilized in the temperature range of $300{\sim}400^{\circ}C$ and subsequently carbonized below $1300^{\circ}C$ in an argon atmosphere. The behaviors of QI formation was examined with varying the heat treatment temperature and the lapse of time of the sample carbonized at various temperatures. And the mechanical property, corrosion resistance, and friction behavior were also measured optimum content of mesophase pitch ensured a dense structure and high $LC_{(002)}$ value, which resulted in high mechanical properties, good corrosion resistance, and low-stable friction behavior.
  6. Joo, Hyeok-Jong;Min, Kyung-Dae;Lee, Nam-Joo 192
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    The Carbon/Carbon composite was prepared from 3D carbon fiber preform and coal tar pitch as matrix precursor. In order to evaluate of ablative characteristics of the composite, liquid rocket system was employed Kerosene and liquid oxygen was used as propellants, operating at a nominal chamber pressure of 330 psi and a nominal mixture ratio (O/F) of 2.0. The results of an experimental evaluation were that high density composite exhibited high, while low density composites showed low erosion resistance. The erosion rate against heat flux was highly depended on the density of the materials. The morphology of eroded fiber showed differently according to collision angle with heat flux on the composite. The granular matrix which derived from carbonization pressure of 900 bar was more resistance to heat flux than well-developed flow type matrix.
  7. Kim, Young-Jeon;Park, Chong-Rae 202
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