http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Tomaru Taisei (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Analysis of spinnable mesophase pitch in terms of lyotropic liquid crystalline solution
Mashio Takashi,Tomaru Taisei,Shimanoe Hiroki,Ha Seung-Jae,Jeon Young-Pyo,Nakabayashi Koji,Miyawaki Jin,Yoon Seong-Ho 한국탄소학회 2023 Carbon Letters Vol.33 No.3
Mesophase pitch is a unique graphitizable material that has been used as an important precursor for highly graphitic carbon materials. In the current study, we propose to consider a spinnable mesophase pitch as a lyotropic liquid crystalline solution composed of solvent components and liquid crystalline components, so-called mesogen or mesogenic components. Among mesophase pitches, the supermesophase pitch is defined as a mesohpase pitch with 100% anisotropy, and can only be observed in pitches with a proportion of mesogenic components exceeding the threshold concentration (TC). We also examined the critical limit of AR synthetic pitch and 5 experimental spinnable mesophase pitches (SMPs). Then, we examined the effect of the solvent component on the minimum required amount of mesogenic component using a selected solvent component instead of their own solvent components. AR pitch showed 100% anisotropy with the least amount of its mesogenic component, THF insoluble components, of 60 wt.%. The solvent component, THF soluble components, extracted from AR-pitch, which has a molecular weight pattern similar to that of the original material but more amount of naphthenic alkyl chains, showed better solvent functionality than those of other THF solubles (THFSs) from other as-prepared spinnable mesophase pitches. This is why a lower amount of AR THFS can produce a supermesophase pitch when combined with the THFI (mesogenic components) of other experimental mesophase pitches. As a result of the current analysis, we define the mesogens as molecules that not only readily stack, but also maintain stacking structures in a fused state in the solution. The solvent component, on the other hand, is defined as molecules with a structure that readily decomposes in a fused state in the solution.
-
Hiroki Shimanoe,Takashi Mashio,Taisei Tomaru,Seung-Jae Ha,전영표,Koji Nakabayashi,Jin Miyawaki,윤성호 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.120 No.-
Spinnable mesophase pitch (SMP) is an important graphitizable precursor for high-performance carbonmaterials. Generally, SMPs show fully developed anisotropic texture, and the pitches contain isotropic contentsmore than 30 wt%, which plays the role of solvent for the mesogenic components in the lyotropic liquidcrystalline system of the pitch. Here, we prepared SMP by blending the mesogenic components of ARmesophase pitch with various isotropic pitches to evaluate the usability of isotropic pitches as solvents. The mesogenic components were prepared by tetrahydrofuran fractionation of AR mesophase pitch. Isotropic pitches with a softening point of 140–220 C were prepared separately by simple heat treatmentof slurry oil (SO) and coal tar pitch (CTP). SMPs were prepared by thermal blending of the above mentionedmesogenic components and isotropic pitches in various blending ratios. CTP-derived isotropic pitchshowed better solvent performance than a SO-derived pitch in terms of anisotropic texture. SMP preparedby blending of the mesogenic components and CTP-derived isotropic pitch with a softening point of 180 Cat the ratio of 4/6 (w/w) showed almost 100% anisotropic texture; the carbon fiber derived from the pitchshowed tensile strength of 2.7 GPa and Young’s modulus of 470 GPa after graphitization at 2,800 C.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
