• Fibers and Polymers
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• 제2권2호
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• pp.75-80
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• 2001

The thermal degradation of poly(ethylene terephthalate-co-isophthalate)s (PETIs) is investigated by using isothermal thermogravimetric analysis at the temperature range of 280-31$0^{\circ}C$. The degradation rate of PETIs is increased as the mole ratio of ethylene isophthaloyl (EI) units in PETIs increases. The activation energies for the thermal degradation of poly(ethylene terephthalate), PETI(5/5), and poly(ethylene isophthalate) are 33.4, 16.6, and 8.9 kcal/mole, respectively. The degradation rate of PETIs is influenced by their volatile cyclic oligomer components formed during the polymerization and the thermal degradation. It is simulated by the rotational isomeric state model that the content of cyclic dimer in PETIs, which is the most volatile cyclic oligomer component, increases with the EI units in PETIs.

• 한국염색가공학회지
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• 제10권1호
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• pp.20-24
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• 1998

Oligomeric extracts of poly(ethylene terephthalate-co-ethylene isophthalate)s [(PET/EI] are analyzed by high performance liquid chromatography(HPLC) and nuclear magnetic resonance spectroscopy (NMR). Existence of separated peaks for small cyclics of trimer and tetramer gives the existence of structural isomeric forms. NMR confirms that cyclization of PET/EI occurs more easily at the site of isophthaloyl unit.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.161-162
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• 2003

The synthesis and properties of aromatic polyesters have been extensively studied recently following the observation of the excellent physical and mechanical properties of thermotropic aromatic polyesters noted in both academia and industry$\^$1∼3/. Most aromatic polyesters are composed entirely of rigid, linear, aromatic ester units and as a result, they have high melting temperatures. (omitted)

• Molecular & Cellular Toxicology
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• 제3권1호
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• pp.53-59
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• 2007

This study was conducted to evaluate the mutagenic potential of dimethyl isophthalate (DMIP) using Ames bacterial reverse mutation test, chromosomal aberration test and mouse lymphoma $tk^{+/-}$ gene assay. As results, in Ames bacterial reversion assay, DMIP was tested up to the concentration of 5,000 ${\mu}g$/plate and did not induce mutagenicity in Salmonella typhimurium strains TA98, TA100, TA1535 and TA1537, and Escherichia coli WP2uvrA with or without metabolic activation (S9 mix). Using cytotoxicity test, the maximal doses of DMIP for chromosomal aberration assay were determined at 1,250 ${\mu}g/mL$, which was a minimum precipitation concentration ($IC_{50}>1,940\;{\mu}g/mL$ or 10 mM) and at 155 ${\mu}g/mL$ ($IC_{50}:155\;{\mu}g/mL$) in the presence and the absence, respectively, of S9 mix. DMIP in the presence of S9 mix induced statistically significant (P<0.001) increases in the number of cells with chromosome aberrations at the dose levels of over 250 ${\mu}g/mL$, when compared with the negative control. However, DMIP in the absence of S9 mix did not caused significant induction in chromosomal aberrant cells. In MLA, DMIP at the dose range of 242.5-1,940 ${\mu}g/mL$ in the presence of S9 mix induced statistically significant increases in mutation frequencies related to small colony growth, whereas any significant mutation frequency was not observed in absence of S9 mix. From these results, it is conclusively suggested that dimethyl isophthalate may be a clastogen rather than a point mutagen.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1991년도 제2차 학술발표초록집
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• pp.33-34
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• 1991

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1996년도 추계 학술발표회
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• pp.280-282
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• 1996

• 한국작물학회지
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• 제51권4호
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• pp.295-297
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• 2006

Potassium (K) distribution in rice (Oryza sativa L.) root was studied by confocal laser microscopy, using potassium sensitive fluorescent dye potassium-binding benzofuran isophthalate (PBFI). Significantly high intensity of K-specific fluorescence was detected at the root cap region followed by meristematic and basal regions. A negligible or fainted fluorescence was observed at the root hairs area. These results suggest that K is heavily distributed in the apical area of rice root, which may be required in higher concentration for division and extension of cells, as it is the rapidly growing region of the root, moreover, may also be involved in water uptake by creating osmotic gradient across membranes.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1999년도 가을 한국섬유공학회 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.517-520
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• 1999

개질제로 1,4-cyclohexandimethanol과 dimethyl isophthalate를 사용하여, PET 규칙적인 분자쇄에 분자유동성이 적은 cyclohexane 구조와 벤젠 unit에 iso형태인 "kink"구조를 도입하여, 개질제의 함량에 따른 공중합물의 열적성질과 그에 따른 morphology를 관찰하였다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.333-334
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• 2003

Poly(trimethylene terephthalate)(PTT)는 결정화 속도가 빠른 결정성 고분자로 최근들어 섬유화에 성공한 이후 활발한 연구가 진행되고 있다. 그러나 U의 빠른 결정화속도와 높은 결정화도 때문에 제품 제조시 곤란을 받고 있다. 한편, PET의 경우 비결정성 고분자인 poly(ethylene isophthalate)(PEI)를 공중합시켜 유리전이온도와 결정화도를 낮추고 결정화속도를 늦추어 PET 섬유의 염색성 및 투명도를 향상시키고, 저온에서의 공정처리를 가능하게 할 수 있다[1-3]. (중략)

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.891-894
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• 2008

Here we describe the new structured electrochromic(EC) materials to improve the three primary colors (RGB). We also report the simply isolated electrochromic unit cell using gel type electrolyte and show cross-talk' free driving of EC display device.