• Carbon letters
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• 제25권
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• pp.89-94
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• 2018

In this study, we tried to prepare an isotropic spinnable pitch which can be useful to prepare the general purpose carbon fiber through the co-carbonization of biomass tar with ethylene bottom oil under two different preparation methods (atmospheric distillation, pressurized distillation). The results showed that the ethylene bottom oil added co-carbonization was very effective to decrease of the oxygen contents for obtaining a stable spinnable pitch. The pressurized distillation was more effective to reduce the oxygen functional groups of pitches than atmospheric distillation. The obtained spinnable pitch by the pressurized distillation showed higher pitch yield of 42% and lower oxygen content of 9.12% than the spinnable pitch by the atmospheric distillation. The carbon fiber derived from the pressurized distillation spinnable pitch by carbonization at $800^{\circ}C$ for 5 min showed that the higher tensile strength of carbon fiber was increased up to 800 MPa.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.276-283
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• 2018

For the first time, polyvinyl chloride (PVC) was used as an easily-handled chlorine source for preparation of isotropic pitch-based carbon fiber (IPCF) incorporating ethylene bottom oil (EO) as a raw material. Pitch precursors were prepared by the chlorination-dehydrochlorination triggered by chlorine radicals originated from PVC; aromatization and poly-condensation reactions occurred by polyene-type radicals from PVC. Radical production and co-carbonization were facilitated by pretreatments of EO through vacuum distillation, bromination, and additional heat treatment. Pitches were prepared by the co-carbonization of pretreated EO and EO containing 20 wt% PVC, and had higher yields and better spinnability than those by simple distillation.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.358-364
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• 2018

An isotropic pitch precursor for fabricating carbon fibres was prepared by co-carbonization of ethylene bottom oil(EBO) and polyvinyl chloride (PVC). Various pre-treatments of EBO and PVC, and a high heating rate of $3^{\circ}C/min$ with no holding time, were evaluated for their effects on the oxidative stabilization process and the mechanical stability of the resulting fibres. Our stabilization process enhanced the volatilization, oxidative reaction and decomposition properties of the precursor pitch, while the addition of PVC both decreased the onset time and accelerated the oxidative reaction. Aliphatic carbon groups played a critical role in stabilization. Microstructural characterization indicated that these were first oxidised to carbon-oxygen single bonds and then converted to carbon-oxygen double bonds. Due to the higher heating rate and lack of a holding step during processing,the resulting thermoplastic fibers did not completely convert to thermoset materials, allowing partially melted, adjacent fibres to fuse. Fiber surfaces were smooth and homogeneous. Of the various methods evaluated herein, carbon fibers derived from pressure-treated EBO and PVC exhibited the highest tensile strength. This work shows that enhancing the naphthenic component of a pitch precursor through the co-carbonization of pre-treated EBO with PVC improves the oxidative properties of the resulting carbon fibers.

• 청정기술
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• 제19권3호
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• pp.272-278
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• 2013

EPDM 고무는 여러 가지 용도에 많이 사용되고 있는 소재이다. 화력발전소의 소각로에서 부산물로 발생하는 버텀애쉬(bottom ash)는 플라이애쉬(fly ash)와는 달리 재활용이 거의 되지 않고 있는데, 본 연구에서는 버텀애쉬 및 탈크를 포함하는 EPDM 복합소재를 roll-mill을 이용하여 제조한 후, 기계적, 열적, 전기적 및 경화 특성 등을 분석하였다. 또한 주사전자현미경(scanning electron microscopy, SEM)을 이용하여 복합재료의 모폴로지를 관찰하였다. 일부의 버텀애쉬는 계면활성제를 이용하여 개질한 후 EPDM 복합재료를 제조하여 개질의 효과를 조사하였다. 결과로 개질된 버텀애쉬 및 탈크를 포함하는 EPDM 복합재료는 우수한 인장 강도 및 인장 탄성률을 나타내었다. EPDM 복합재료의 체적 저항은 $10^{14}{\Omega}cm$ 이상으로 전기 절연체로서 저항 임계치를 만족하였고, 열적 물성 결과 버텀애쉬 및 탈크가 EPDM의 열적 안정성을 높여 주는 것으로 확인되었다.