• 한국군사과학기술학회지
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• 제22권1호
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• pp.35-41
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• 2019

Ferrocene and ferrocene derivatives have been widely used as a burning rate catalyst for composite solid propellants. However, its tendency to migrate through the propellant grain and to crystallize at the surface changes the composition of propellant which results in unpredictable burning rate. To overcome the weakness of ferrocene catalyst, we designed a polymer containing ferrocene, poly(glycidyl azide-co-glycidyl ferrocenyl ether) (GAFP). GAFPs were synthesized from poly(epichlorohydrin-co-glycidyl ferrocenyl ether) (PEGF) which has ferrocenyl ethers in its pendant groups. The structures of GAFPs were confirmed by FT-IR, $^1H$ and $^{13}C$ NMR spectral analyses. Thermal properties of the GAFPs were evaluated using differential scanning calorimeter (DSC). As the contents of ferrocene increased, the glass transition temperature ($T_g$) of the GAFPs shifted to a higher temperature, and the decomposition temperature ($T_d$) decreased because the ferrocene worked as a burning rate catalyst.

• Journal of Preventive Medicine and Public Health
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• 제43권2호
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• pp.131-137
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• 2010

Objectives: Bisphenol A diglycidyl ether (BADGE) is a liquid compound obtained by condensation of two molecules of epichlorohydrin with one molecule of bisphenol A. General and reproductive toxicity with BADGE has been reported higher than 1000 mg/kg/day. This study was performed to show the effects of acute exposure to BADGE below 1000 mg/kg/day on the testis in adult male rats. Methods: BADGE was administered by gastric lavage in a single dose of 500, 750, 1000, and 2000 mg/kg/day in 8-week old male SPF Sprague-Dawley rats. The right testis was processed for light microscopic analysis. The left testis was homogenized and spermatids were counted to determine the daily sperm production and daily abnormal sperm production. The sperm count, sperm motility, and incidence of abnormal sperm were estimated in the epididymis. In testicular sections, the seminiferous tubules were observed for qualitative changes. The progression of spermatogenesis was arbitrarily classified as full-matured, maturing, and immature. The specimen slide was observed at 3 points and 10 seminiferous tubules were evaluated at each point. Results: The male rats exposed to single oral dose of BADGE at 750, 1000, and 2000 mg/kg/day were significantly increased the number of immature and maturing sperm on the testis. There were no significant differences with respect to sperm head count, sperm motility, and sperm abnormality in the BADGE treatment groups. Conclusions: These results suggest that single oral exposure of BADGE 750 mg/kg/day can affect adult male testis development.

• 한국의류산업학회지
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• 제14권2호
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• pp.311-319
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• 2012

The purpose of this study is to investigate the dyeing property of gromwell on modified cotton fabric by chitosan. Modified cotton fabrics were manufactured by crosslinking agent epichlorohydrin in the presence of chitosan. Gromwell colorants were extracted with methanol. Modified cotton fabrics dyed using gromwell were post-mordanted using Al, Fe and Cu. The dyeability (K/S) and color factors (L, a, b, ${\Delta}E$ and h) of modified cotton fabrics were measured by computer color matching. Additionally the fastness to washing and light were also investigated. The dye-uptake of modified cotton fabrics increased with the dyeing time. The saturated dyeing time was about 10minutes at $50^{\circ}C$. The dyeability (K/S) was remarkably increased with increasing content of chitosan because of having a amine group of chitosan. Modified cotton fabrics were dyed yellowish red by non and Fe mordanting, blueish red by Al and Cu mordanting, respectively. The washing fastness of non, Al, Fe and Cu mordant in the presence and absence of chitosan were increased $1{\rightarrow}2$, $3{\rightarrow}4$, $4{\rightarrow}4-5$ and $4{\rightarrow}4-5$ respectively. And light fastness of non, Al, Fe and Cu mordant in the presence and absence of chitosan were increased $1{\rightarrow}1-2$, $1{\rightarrow}1-2$, $1.2{\rightarrow}2.3$ and $1-2{\rightarrow}2$ respectively.

• Journal of Microbiology and Biotechnology
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• 제18권8호
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• pp.1445-1452
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• 2008

An open reading frame (ORF) encoding a putative epoxide hydrolase (EHase) was identified by analyzing the genome sequence of Sphingophyxis alaskensis. The EHase gene (seh) was cloned and expressed in E. coli. To facilitate purification, the gene was fused in-frame to 6$\times$ histidine at the C-terminus. The recombinant EHase (rSEH) was highly soluble and could be purified to apparent homogeneity by one step of metal affinity chromatography. The purified SEH displayed hydrolyzing activities toward various epoxides such as styrene oxide, glycidyl phenyl ether, epoxyhexane, epoxybutane, epichlorohydrin, and epifluorohydrin. The optimum activity toward styrene oxide was observed at pH 6.5 and $35^{\circ}C$. The purified SEH showed a cold-adapted property, displaying more than 40% of activity at low temperature of $10^{\circ}C$ compared with the optimum activity. Despite the catalytic efficiency, the purified SEH did not hydrolyze various epoxides enantioselectively. $K_m$ and $k_{cat}$ of SEH toward (R)-styrene oxide were calculated as 4$\pm$0.3 mM and 7.42$s^{-1}$ respectively, whereas $K_m$ and $k_{cat}$ of SEH toward (S)-styrene oxide were 5.25$\pm$0.3 mM and 10.08$s^{-1}$ respectively.

• 한국응용과학기술학회지
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• 제36권4호
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• pp.1443-1459
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• 2019

리글리세린지방산에스터 비이온계면활성제는 식품 등에 오래전부터 사용해 왔으며 PEG계 비이온계면활성제의 안전성 문제에 대한 대안으로 제시되고 있다. 폴리글리세린지방산에스터 계면활성제는 친수기인 폴리글리세린과 친유기인 지방산을 결합시켜 합성된다. 친수기인 폴리글리세린은 글리세린, 글리시돌, 에피클로로히드린 등을 이용하여 중합되는 데 폴리글리세린 중합반응의 주요 이슈는 분기·환상형태가 아닌 직쇄형태의 폴리글리세린의 함량을 높이고 중합도의 분포를 좁히는 것이다. 친수기인 폴리글리세린에 지방산계 친유기를 결합시키는 방법에는 에스터화 반응 등의 화학적 합성법과 지방분해효소를 이용한 효소 합성법이 있다. 폴리글리세린지방산에스터 합성의 주요 이슈는 에스터화정도를 조절하면서 반응수율을 높이고 부반응을 억제하는 것이다.

• 한국의류산업학회지
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• 제10권5호
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• pp.748-755
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• 2008

The purpose of this study is to investigate the effect of chitosan treatment on the dyeing of cotton fabric using charcoal as colorants. Particle size of charcoal, dyeability(K/S), SEM morphology of dyed fabrics and color fastness were also investigated. In this study, cotton fabrics were treated with a crosslinking agent epichlorohydrin in the presence of chitosan to provide the cotton fabrics the dyeing properties of natural dye by the chemical linking of chitosan to the cellulose structure. The results obtained were as follows; Mean average diameter of charcoal was 1.44 ${\mu}m$. According to various conditions, the dyeing effects of 1% chitosan treatment on the dyeing of cotton fabrics using charcoal were the highest with 10%(owb) of charcoal at $90^{\circ}C$ for 120minutes and non-treatment of cotton fabrics were the highest with 15%(owb) of charcoal at $90^{\circ}C$ for 150minutes. Overall, K/S value of 1% chitosan treatment of cotton fabrics on the natural dyeing using charcoal was higher than non-treatment of cotton fabrics. It was observed the surfaces of cotton fabrics treated with chitosan were adsorbed with charcoal powders of particle size more than a non-treated chitosan fabric by SEM. The cotton fabrics were dyed with blackish gray color by charcoal gradually according to treating chitosan. The K/S value, that is indicative of dye affinity, became higher as the increase of treated chitosan concentration. The color fastness of charcoal, washing and light fastness was excellent as 4-5 grade.

• 한국의류산업학회지
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• 제10권4호
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• pp.552-559
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• 2008

Recent days, various inner wears, sheets and interior goods are manufactured using materials dyed with loess emphasizing its improved blood circulation, metabolism, anti-bacterial, deodorizing properties, and far-infrared ray emissions. The purpose of this study is to investigate the effect of chitosan treatment on the dyeing of cotton fabric using loess as colorants. Particle size of loess, the morphology and dyeability(K/S) of chitosan crosslinked cotton fabrics, and washing durability of loess dyed cotton fabric were investigated. In this study, cotton fabrics were treated with a crosslinking agent, epichlorohydrin, in the presence of chitosan to improve the dyeing properties of cotton fabrics with natural dye by the chemical linking of chitosan to the cellulose structure. This process was applied by means of the conventional mercerizing process. The results obtained were as follows; Mean average diameter of loess was $1.13{\mu}m$. According to various conditions, the optimum dyeing conditions for cotton fabrics pretreated by 1% chitosan treatment was where 10%(owb) of loess was applied at $90^{\circ}C$ for 120minutes, while for cotton fabrics without chitosan treatment was where 15%(owb) of loess was applied at $90^{\circ}C$ for 150minutes. Overall, K/S value of loess dyed cotton fabric pretreated with 1% chitosan was higher than that of cotton fabrics without chitosan treatment. The Color fastness, washing fastness and light fastness of loess were excellent as 4-5grade.

• 한국식품위생안전성학회지
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• 제13권1호
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• pp.34-40
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• 1998

수산계 폐기물로부터 chitin 유도체의 다양한 응용에도 불구하고 chitin 의 상업적 이용은 적절한 용매의 부재와 화학적 제한성으로 인하여 제한적으로 이용되었다. 그러므로 Mima의 방법을 응용하여 NaOH 농도, 반응시간, 온도 등을 조절하여 탈아세틸화반응에 의한 다양한 점도가 다른 chitosan을 제조하였으며, 2종의 각Y제를 이용하여 가교결합에 의한 결정성을 증가시킨 가교 chitosan을 제조하였따. 제조한 점도가 다른 chitosan과 가교 chitosan 유도체를 다양한 분석기기를 이용하여 측정하였다. chitosandmf 제조시 반응시간을 높이거나 반응온도를 높이면 탈아세틸화는 높아지나 분자사슬의 크기, 즉 점도와 분자량은 감소하였다. 반응온도, 반응시간과 알칼리 농도에 따라 활용분야에 맞은 chitosan을 제조할수 있다.

• 공업화학
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• 제3권4호
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• pp.649-656
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• 1992

t-Butyl hydroperoxide(TBHP)에 의한 염화알릴의 에폭시화에 의해서 에피클로로히드린을 합성하는데 실리카에 담지된 몰리브데늄 촉매를 사용하였다. 속도론적 연구는 회분 반응기를 사용하여 $60-80^{\circ}C$, 10기압에서 TBHP/염화알릴의 농도비를 0.01-0.1의 범위내에서 수행하였다. t-butyl alcohol(TBA)에 의해서 염화알릴의 에폭시화 반응이 억제되었고, 반응속도는 Michaelis-Menten 형태의 속도식으로 표현할 수 있었다. 반응기구는 TBHP와 TBA의 가역흡착과 $Mo/SiO_2$에 흡착된 TBHP와 염화알릴의 표면반응으로 설명할 수 있었다.

• 대한화학회지
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• 제19권3호
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• pp.198-206
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• 1975

갇광성 관능기를 갖는 중합체, 이를테면 polyglyceryl phthalate(PG), bisphenol A-epichl-orohydrin 축중합체(BE) 및 polyvuinyl alcohol(PVA)의 naphthoquinone-1,2-diazide-5-sulfonyl esters(PGND, BEND 및 PVAND)를 합성하였다.빙점강하법으로 측정한 모체수지들의 분자량은 PG의 경우 650${\sim}$1500, BE는 780${\sim}$1320이었다. PG, BE 및 PVA를 naphthoquinone-1,2-diazide-5-sulfonyl chloride로 ester화 시켜 얻은 PGND, BEND 및 PVAND의 원소분석의 계산치와 실측치가 잘 일치하고 있는 점으로 보아 모체수지인 PG, BE 및 PVA의 중합도는 ester화 된 경우에도 변하지 않는다는 것을 알 수 있었다.