• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.1
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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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• v.43 no.2
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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.

• Fashion & Textile Research Journal
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• v.14 no.2
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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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• v.18 no.8
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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.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1443-1459
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• 2019

Polyglycerol fatty acid ester nonionic surfactants have been used for a long time in foods and have been suggested as an alternative to the safety problems of PEG based nonionic surfactants. The polyglycerol fatty acid ester surfactants are synthesized by combining a hydrophilic polyglycerin and a lipophilic fatty acid. The hydrophilic polyglycerin is polymerized using glycerin, glycidol, epichlorohydrin, etc. The main issues of the polyglycerol polymerization reaction are to increase the content of the polyglycerol in the form of linear rather than branched or cyclic forms and to narrow the distribution of the degree of polymerization. The method of binding a lipophilic fatty acid group to a hydrophilic polyglycerin includes chemical synthesis such as esterification reaction and enzyme synthesis using lipase enzyme. The main issues of polyglycerin fatty acid ester synthesis are to increase the yield and to control the degree of esterification while reducing side reactions.

• Fashion & Textile Research Journal
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• v.10 no.5
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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.

• Fashion & Textile Research Journal
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• v.10 no.4
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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.

• Journal of Food Hygiene and Safety
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• v.13 no.1
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• pp.34-40
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• 1998

Chitin is known as biodegradable natural polymer. But, in spite of various application of chitin from waste marine sources, commercial use of chitin has been limited due to highly resistance to chemicals and the absense of proper solvents. Therefore, we studied that another viscosity chitosan were prepared from chitin which were deacetylated under various concentration of NaOH solution, reaction time and temperature by the application of Mirna's method. The major parameters for these manufacturing methods were found to be concentration of alkali solution, reaction time and temperature etc. Besides, we studied that various chitosan derivatives were prepared from chitin by crosslinkage with epichlorohydrin and 1,3-dichloropropanol. The effects of these parameters on another viscosity(molecular weight) chitosan and crosslinked chitosan dervatives were investigated by various analysis apparatus. SEM analysis showed that both chitin and chitosan had a particle shaped morphology and another molecular weight chitosan according to the particle size was much smaller than that of chitin.

• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.649-656
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• 1992

The synthesis of epichlorohydrin was carried out by the epoxidation of allyl chloride with tert-butyl hydroperoxide(TBHP) over silica supported molybdenum catalyst. Kinetic study was performed at $60-80^{\circ}C$ and 10 atm with the molar ratio of TBHP/Allyl chloride between 0.01 and 0.1 in a batch reactor. The epoxidation of allyl chloride was inhibited by tert-butyl alcohol and kinetic data could be represented by Michaelis-Meten type rate equation. The reaction mechanism could be explained by the combination of reversible adsorption of TBHP and tert-butyl alcohol accompanied by reaction of allyl chloride with TBHP adsorbed on $Mo/SiO_2$ catalyst.

• Journal of the Korean Chemical Society
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• v.19 no.3
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• pp.198-206
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• 1975

Polymers with photosensitive functional groups, the naphthoquinone-1,2-diazide-5-sulfonyl esters(PGND, BEND and PVAND) of polyglyceryl phthalate(PG), bisphenol A-epichlorohydrin polycondensate(BE) and polyvinyl alcohol(PVA), were prepared. The molecular weights of the starting materials were determined by the cryoscopic method, i.e., in the range of 650${\sim}$1200 for PG and 780${\sim}$1320 for BE, PGND, BEND and PVAND were prepared by esterification of PG, BE and PVA with naphthoquinone-1,2-diazidie-5-sulfonyl chloride, and the replacements of such a functional groups were confirmed by the infrared absorption spectra and elemental analyses. The good agreement between the observed values of elemental analyses (PGND, BEND and PVAND) and the calculated values, indicated that the degree of polymerization did not change in the course of esterification of PG, BE and PVA.