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Volume 1975 (1975)
- Issue 83 Pages 135-
- Issue 82 Pages 87-
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Volume 1975, Issue 82
Displaying 1-8 of 8 articles from this issue
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Behavior of Meso-carbon Microbeads (Type-C) in PitchHiroshi TSUTSUI, Kenji FUKUDA, Shoichi OI, Yasuhiro YAMADA, Hidemasa H ...1975 Volume 1975 Issue 82 Pages 87-92
Published: July 30, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSIn order to investigate the nucleation and the growth mechanisms of carbonaceous mesophase in pitch, meso-carbon microbeads were added in pitch, heat-treated at 300-430°C for a certain period, and observed by using a polarized light microscope. Pitch used was the quinoline soluble coal-tar pitch, and meso-carbon microbeads were Type-C.
With increasing heat treatment temperature (HTT) and residence time, Type-C added in pitch changes as follows; Type-C has optically isotropic substances showing a small spot appearance at its interior (at HTT 300 and 350°C). The optically isotropic substance is transformed from the small spot state to the spherical state with increasing residence time at HTT 350-400°C, resulting in the growth of Type-C. When Type-C coalesces each other to form bulk mesophase, the proportion of the isotropic substance in the mesophase is reduced. The isotropic substance in Type-C can be extracted easily by quinoline. These results suggest that the growth of mesophase is resulted not only from the molecular alignment of pitch at the mesophase surface but also from the permeation of the molecules constructing pitch into the mesophase, which seems to transform the isotropic substances to anisotropic ones in the mesophase.View full abstractDownload PDF (6531K) -
Correlation between Meso-carbon Microbeads added and Mesophase formed in PitchHiroshi TSUTSUI, Shoichi OI, Yasuhiro YAMADA, Hidemasa HONDA1975 Volume 1975 Issue 82 Pages 93-101
Published: July 30, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSMeso-carbon microbeads were added in various pitches; coal-tar pitch, quinoline soluble coal-tar pitch (QS coal-tar pitch) and asphalt pitch, and these pitches were heat-treated at 400-430°C. A correlation between the microbeads added and the mesophase formed in pitch was investigated by using a polarized light microscope.
The obtained results are follows;
(1) In the case of addition of the microbeads of Type-M in QS coal-tar pitch, the growth of Type-M is observed but new mesophase is not formed in the pitch. For Type-P in QS coal-tar pitch, new mesophase spherules are formed in the pitch and their growth is predominant rather than the growth of Type-P . This is similar to the case of addition of Type-C and Type-M in asphalt pitch. From these results, it is considered that the growth of the added microbeads as well as the coalescence of new mesophase and the added microbeads requires similarity in molecular structure between pitch and meso-carbon microbeads.
(2) In the case of addition of the microbeads of Type-C, Type-P and Type-M in coal-tar pitch containing metaphase, the microbeads added do not grow, and new mesophase spherules surrounded with metaphase are nucleated and grown. Thus the metaphase in pitch plays an important role in the formation of mesophase . In particular, the formation of mesophase spherules at the surface of metaphase in pitch is predominant than at the surface of microbeads themselves or of metaphase on Type-M. From these results, it is suggested that the metaphase in pitch has active site on itself for the formation of mesophase.
(3) In the case of addition of Type-P in coal-tar pitch or addition of Type-C and Type-M in asphalt pitch, the microbeads added are dispersed in the pitch over the wide range, and coalesced with new mesophase formed in the pitch. It seems that coal-tar pitch is able to mix and melt homogeneously with asphalt pitch through the medium of mesophase.View full abstractDownload PDF (4720K) -
Yasumasa YAMASHITA, Koji OUCHI, Minoru SHIRAISHI1975 Volume 1975 Issue 82 Pages 102-106
Published: July 30, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThree types of phenolic resin, i. e. phenol-formaldehyde resin (Ph), 3-methyl phenol-formaldehyde resin (3-MPh) and 3, 5-dimethyl phenol-formaldehyde resin (3, 5-DMPh) were synthesized in oxidizing and inert atmospheres. By oxidation, the carbonyl and carboxyl groups were introduced into resins, which was concluded from the increase in the infra red absorption in the region of 1600-1700 cm-1 and the evolution of CO and CO2 gases at relatively low temperature as below 400°C.
The influence of oxidation of resin during synthesis on the graphitizability of related carbon was very remarkable for 3, 5-DMPh resin, that is, the carbon obtained from oxidized 3, 5-DMPh resin was non-graphitizing one, while the carbon from the same resin but not oxidized was graphitizing. The other resins, Ph and 3-MPh resins, gave non-graphitizing carbon, and only slight difference was observed in the graphitizability between two carbons obtained from oxidized and non-oxidized Ph or 3-MPh resin.View full abstractDownload PDF (2421K) -
Masatoshi TSUCHITANI, Yoshihiko HASE, Yoshiharu ITO, Yasuhiro YAMADA, ...1975 Volume 1975 Issue 82 Pages 107-113
Published: July 30, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSWhen petroleum residues are heat-treated at 350-500°C, mesophase spherules are formed in residues. For mesophase spherules are insoluble in organic solvents such as quinoline, those are separated from pitch matrix by solvent fractionation. Mesophase spherules separated are called “meso-carbon microbeads”
In order to investigate the influence of the characteristics of residue on those of the meso-carbon microbeads, the meso-carbon microbeads were made from 6 kinds of residues and were studied on the characteristics of them. The following results were obtained;
(1) The meso-carbon microbeads having high value of C/H (atomic ratio) are obtained from the raw residue having high value of C/H.
(2) The meso-carbon microbeads having high intensity of infrared absorption assigned to aliphatic C-H vibration are obtained from the raw residue having high intensity of the same infrared absorption.
(3) Palaffinic hydrocarbons of straight long side chain having carbon number from 8 to 20 are included in the meso-carbon microbeads made from the residue mainly consisting of aliphatic hydrocarbons.
(4) Graphitizability of the meso-carbon microbeads depends on its C/H ratio. When these meso-carbon microbeads are heat-treated at 2800°C, the thickness of crystallite layer (Lc (002) ) of the meso-carbon micro beads made from the residue having high value of C/H ratio are larger than those from the residue having low value of C/H ratio. Graphitizability of the meso-carbon microbeads are similar to that of coke made from the same residue.
From these results, it is considered that characteristics of the meso-carbon microbeads are similar to those of raw residue from which meso-carbon microbeads are made.View full abstractDownload PDF (4616K) -
Rokuro FUJII, Kanii MATSUO1975 Volume 1975 Issue 82 Pages 114-115
Published: July 30, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (269K) -
Naoki OKUYAMA1975 Volume 1975 Issue 82 Pages 116-118
Published: July 30, 1975
Released on J-STAGE: June 28, 2010
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Kazuo KOBAYASHI, Yasuhiro MATSUSHITA, Ichitaro OGAWA, Hidemasa HONDA1975 Volume 1975 Issue 82 Pages 118-119
Published: July 30, 1975
Released on J-STAGE: June 28, 2010
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[in Japanese], [in Japanese]1975 Volume 1975 Issue 82 Pages 120-126
Published: July 30, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (1187K)
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