http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
폴리히드록시아미드 섬유의 제조와 열처리에 따른 구조-물성 상관관계(I) -다양한 고화조건에 따른 고화거동-
강찬솔,지민호,백두현,Kang, Chan Sol,Jee, Min Ho,Baik, Doo Hyun 한국섬유공학회 2013 한국섬유공학회지 Vol.50 No.4
Polyhydroxyamide (PHA) was synthesized using low temperature solution polymerization of 3,3'-dihydroxybenzidine (DHB) and isophthaloyl chloride (IPC) in N,N-dimethylacetamide (DMAc). In order to study wet-spinning of PHA fibers, the diffusion property of DMAc in various coagulants and the effect of coagulation bath temperature were evaluated. The initial diffusion rate of DMAc, and the SEM images and mechanical properties of PHA fibers, demonstrated that the coagulation in ethanol at $20^{\circ}C$ was the most optimal among all the conditions examined. The tensile strength and initial modulus of PHA fibers increased, while its breaking strain decreased with increasing spin draw ratio (SDR). The wide-angle X-ray diffraction (WAXD) experiment revealed that the crystallinity of PHA fibers increased with increasing SDR. The process-structure-property relationship among PHA fibers under various coagulation conditions was also investigated.
MWNT와 Graphite 전도성 나노입자를 함유한 폴리우레탄 하이브리드 나노복합체의 기계적 물성 및 전기적 특성 평가
강찬솔,지민호,백두현,Kang, Chan Sol,Jee, Min Ho,Baik, Doo Hyun 한국섬유공학회 2012 한국섬유공학회지 Vol.49 No.3
The synergistic effects of multi-walled carbon nanotubes (MWNT) and graphite on the structural features and mechanical and electrical properties of polyurethane (PU) nanocomposites were investigated as functions of filler content. SEM images of the PU/hybrid nanocomposite exhibit that the MWNTs and graphite are dispersed well in the PU matrix and form an interconnected network structure. Accordingly, the tensile strength and strain-at-break of the PU/hybrid nanocomposites were much higher than those of the PU/MWNT and PU/graphite nanocomposites at the same filler content. In addition, it is found that the PU/hybrid nanocomposite containing 1.25 wt% MWNTs and 1.25 wt% graphite shows the electrical conductivity of $1.2{\times}10^{-4}S/cm$, which is higher by three orders than that of PU/graphite nanocomposite containing 20.0 wt% graphite. The highly improved mechanical and electrical properties of the PU/hybrid nanocomposite are thought to be due to the interconnected network structure of MWNTs and graphite in the PU matrix.
폴리히드록시아미드 공중합체의 열 고리화 거동에 대한 연구
강찬솔,민재호,남민우,서무송,지민호,백두현,Kang, Chan Sol,Min, Jae Ho,Nam, Min Woo,Seo, Moo Song,Jee, Min Ho,Baik, Doo Hyun 한국섬유공학회 2016 한국섬유공학회지 Vol.53 No.5
A series of polyhydroxyamide copolymers (Co-PHAs) containing 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (BAHHFP) and/or bis(3-amino-4-hydroxyphenyl) sulfone (BAHS) were synthesized via a low-temperature solution polymerization method. The synthesized Co-PHAs were characterized by Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). All the Co-PHAs were found to be soluble in organic solvents with or without LiCl. The chemical structures of the Co-PHAs were identified using FT-IR spectroscopic analysis. The DSC and TGA results showed that the inclusion of BAHHFP and/or BAHS in the Co-PHAs reduced the thermal cyclization temperatures as compared to DHB, which is due to the difference in the rotational energy of the diamine monomers.
지민호,강찬솔,여문진,백두현,Jee, Min Ho,Kang, Chan Sol,Yeo, Moon Jin,Baik, Doo Hyun 한국섬유공학회 2015 한국섬유공학회지 Vol.52 No.6
Polyhydroxyamide (PHA) was synthesized by low-temperature solution polymerization of 3,3'-dihydroxybenzidine and terephthaloyl chloride. Then, pure PHA and PHA nanocomposite fibers, including multi-walled carbon nanotube (MWNT), were prepared by a wet-spinning process. The structural characteristics, thermal properties, and mechanical performances, such as tensile strength, initial modulus, and compressive strength, of the PHA fibers were investigated using FT-IR, TGA, and a tensile testing machine. The TGA results show that the PHA fiber has excellent thermal stability at high temperatures and can undergo thermal cyclization to yield PBO fiber. The tensile mechanical properties of PHA nanocomposite fibers were better than those of pure PHA fiber, and they were improved on increasing the MWNT content. The highly improved mechanical properties of the nanocomposite fibers are thought to be related to the strong interfacial interactions between the PHA matrix and MWNT.
플루오르기가 도입된 폴리히드록시아미드의 합성과 고리화 반응
박채원,강찬솔,백민정,백두현,Park, Chae Won,Kang, Chan Sol,Paik, Min Jung,Baik, Doo Hyun 한국섬유공학회 2014 한국섬유공학회지 Vol.51 No.5
We have synthesized four kinds of polyhydroxyamides (PHAs) via low-temperature solution polymerization of 2,2-bis(3-amino-4-hydoxyphenyl)hexafluoropropane or 3,3'-dihydroxybenzidine with isophthaloyl chloride or terephthaloyl chloride in N,N-dimethylacetamide and 1-methyl-2-pyrrolidone, respectively. The chemical structures of the synthesized PHAs and the polybenzoxazoles(PBOs) obtained by heat-treatment of the PHAs were identified using FT-IR spectroscopic analysis. We studied the thermal cyclization behavior of the PHAs and related this behavior to their chemical structures. DSC and TGA results showed that both the thermal cyclization temperatures and the thermal stabilities were decreased by introduction of fluorine into the main chain of the PHAs.
방향족 폴리히드록시아미드의 합성과 열적 고리화 거동(II) -플루오르 치환체의 영향-
지민호,백민정,강찬솔,백두현,Jee, Min Ho,Paik, Min Jung,Kang, Chan Sol,Baik, Doo Hyun 한국섬유공학회 2013 한국섬유공학회지 Vol.50 No.5
Polyhydroxyamide (PHA) was synthesized via low-temperature solution polymerization of 3,3'-dihydroxybenzidine with isophthaloyl chloride, and the derivatives of PHA containing fluoro-substituents were investigated for exploring their potential application as new thermally stable polymer material. The structural properties, solubility, and thermal cyclization of the PHA and its derivatives were characterized using FT-IR, DSC, and TGA to derive the relationship between the structure of the PHA derivatives and the thermal properties and cyclization behavior of the polymer. The PHA derivatives containing fluoro-substituents were readily soluble in a variety of solvents without LiCl, whereas the pristine PHA was soluble only in the presence of LiCl. The DSC analyses under isothermal conditions showed that the PHA derivatives exhibited a faster cyclization rate than the pristine PHA at $220^{\circ}C$ and $250^{\circ}C$. In addition, the DSC and TGA results revealed that the PHA derivatives could be cyclized into the corresponding polybenzoxazoles at lower temperatures than the pristine PHA; this could be attributed to the lower thermal activation energy of the derivatives owing to the introduction of the fluoro-substituents.
시아노기를 도입한 파라계 아라미드 공중합체의 합성과 특성분석
여문진,구남대,장은지,강찬솔,정영규,백두현,Yeo, Moon Jin,Gu, Nam Dae,Jang, Eun Ji,Kang, Chan Sol,Jeong, Young Gyu,Baik, Doo Hyun 한국섬유공학회 2014 한국섬유공학회지 Vol.51 No.3
Poly(p-phenylene terephthalamide) (PPTA) and poly(2-cyano-1,4-phenylene terephthalamide) (CNPPTA)-based copolymers were synthesized using a low temperature polycondensation reaction between terephthaloyl chloride, 2-cyano-1,4-phenylene diamine, and/or 1,4-phenylene diamine in a N-methylpyrrolidinone solvent containing 2% $CaCl_2$. The molecular structures and thermal stabilities of PPTA, CNPPTA, and copolymers of the two with different cyano group contents were characterized using FT-IR spectroscopy and thermogravimetric analysis, respectively. The liquid crystalline states and polymer concentration-dependent viscosities of NMP/$CaCl_2$ solutions containing different CNPPTA copolymer concentrations were investigated using polarized optical microscopy and viscometry, respectively. It was found that CNPPTA polymers with higher cyano group contents were more soluble in polar organic solvents, such as NMP, DMAc, and DMF, and that CNPPTA polymer solutions based on the NMP/$CaCl_2$ system formed liquid crystalline structures above certain critical polymer concentrations. In addition, TGA results revealed that, although the initial degradation temperatures of CNPPTA copolymers were quite comparable to that of PPTA, their char yields at $800^{\circ}C$ were far higher.