• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.5-8
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• 1998

폴리에스테르 공중합체의 합성에 이용될 수 있는 에스테르 교환 반응은 alcoholysis, acidolysis 및 transesterification 반응들에 의해 복합적으로 진행되며 이 때 각각의 반응 속도를 비교하여 보면 어느 한 쪽 분자쇄의 말단 알코올기가 다른 쪽 분자쇄의 에스테르기를 공격하는 alcoholysis 반응이 가장 빠르고 카르복실기가 에스테르를 공격하는 acidolysis 및 두 고분자 주쇄의 에스테르기 상호간에 발생하는 transesterification 반응들은 alcoholysis 반응에 비해 느린 것으로 알려져 있다. (중략)

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.385-390
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• 2010

Transesterifications of vegetable oils (soybean oil, grapeseed oil, corn oil, canola oil) by ultrasonic energy were examined on various catalysts for biodiesel production. Reaction activities of the transesterifications were evaluated to the ultrasonic energy and thermal energy. The physicochemical properties and product distribution were also investigated to the biodiesels produced from the oils in the reaction using ultrasonic energy. The yields of fatty acid methyl ester (FAME) on the alkali catalysts were higher than those on the acid catalysts. The highest FAME yield was obtained as 83% on potassium hydroxide catalyst in the transesterification. The effective reaction conditions by ultrasonic energy were 1 wt% catalyst loading and 6:1 molar ratio of methanol to vegetable oils. The reaction rate of the transesterification by ultrasonic energy was faster than that by thermal energy. The acid values of the biodiesel products were improved above 30% compared to those of the feedstocks.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.183-186
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• 2001

폴리에스테르/폴리아미드의 블렌드는 두 고분자의 단점을 상호 보완할 수 있을 뿐만 아니라 조성비에 의해 원하는 물성을 부여할 수 있는 장점이 있다. 이들 블렌드 중에서 폴리(에틸렌 테레프탈레이트)(PET)/폴리아미드(PA)의 블렌드의 경우 일반적인 폴리에스테르계의 블렌드에서 일어나는 에스테르 교환반응과 마찬가지로 에스테르-아미드 교환반응이 일어나며 이를 이용하여 두 고분자간의 상용성을 향상시키려는 연구가 보고된 바 있다. (중략)

• Journal of the Korean Chemical Society
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• v.41 no.3
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• pp.157-165
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• 1997

The transesterification reaction could be used to the technical production as it forms an in-situ compatibilizer during the processing of polymer blends. Thus, TR-4,6(poly(tetramethylene-4,4'-terephthaloyldioxydibenzoate-co-hexametylene-4,4'-terephthaloyldioxydibenzoate), one of thermotropic liquid crystalline polymers was synthesized and was blended with PBT(polybutylene terephthalate), one of engineering plastics, to study the transesterification reaction. The transesterification reactions between two components, TR-4,6 and PBT, were monitored by IR, DSC and $^{13}C-NMR$ and analyzed by a statistical treatment method. Also, the reaction rates and the sequence distributions of repeating unit were (calculated and) invesitigated.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.487-492
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• 2013

Transesterifications of waste oils mixed with animal tallows and vegetable oil by ultrasonic energy were examined over various catalysts for biodiesel production. Reaction activities of the transesterification were evaluated to the ultrasonic energy and thermal energy. The physicochemical properties of feedstock and products were also investigated to the biodiesels produced from the oils in the reaction using ultrasonic energy. The highest fatty acid methyl ester (FAME) yield was obtained on the potassium hydroxide catalyst in the transesterification by ultrasonic irradiation. The effective reaction conditions by ultrasonic energy were 0.5 wt% catalyst loading and 6:1 molar ratio of methanol to the mixed oils. The reaction rate of the transesterification by ultrasonic energy was faster than that by thermal energy. The highest yields of FAME were obtained as 80% in 5 min and the reaction equilibrium reached at that time.

• Journal of the Korean Chemical Society
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• v.26 no.1
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• pp.49-57
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• 1982

Transesterification reactions were carried out with myo-inositol and five fatty acid methyl esters such as methyl laurate, methyl myristate, methyl palmitate, methyl stearate and methyl oleate in the dimethylsulfoxide solvent. Their products were separated by both thin layer chromatography and column chromatography, and myo-inositol monoesters were quantitatively separated by counter current distribution. We measured their surface tension, foaming power and emulsifying power, determined critical micelle concentrations by the color method, and evaluated their hydrophilic-lipophilic balance. The results show that myo-inositol monoesters exhibit surface activites.

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.370-375
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• 1996

• Proceedings of the KAIS Fall Conference
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• 2000.10a
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• pp.251-254
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• 2000

실험실에서 합성된 phenylthiazole ester 와 p-chlorophenylthiazole ester 그리고 methoxyphenylthiazole ester 각각의 기질에 대한 백혈구 에스터라제의 활성화 감도 등을 검토한 후, 반응 특이성이 좋고 감도가 높은 기질을 선택하여, 요 중에 존재하는 백혈구 수를 간접적으로 측정함은 물론, 반응 단계에 따라 구분이 가능한 요 중 백혈구 측정용 시험지를 개발에 필요한 조건을 최적화 하고자 하였다. 또한, 상품화된 기존의 아미노산 에스테르 기질과 비교 검토하여 그 차이가 발견되면 간편하고 경제성을 고려한 에스테르 기질을 개발함은 물론, 발색성 효소 기질의 결점을 보완하기 위하여 그 개선책을 검토하였다. 그 결과 Thiazole 유도체와 아미노산 유도체로부터 만들어진 새로운 에스테르인 phenyl thiazole 아미노산 에스테르인 methoxyphenyl thiazole 아미노산 에스테르 기질이 기존의 상품과 비교했을 때 그 효능이 우수하였다.

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.364-369
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• 1996

• Proceedings of the Korean Fiber Society Conference
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• 1992.06b
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• pp.97-98
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• 1992