• Title/Summary/Keyword: Epichlorohydrin(ECH)

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Batch Production of Chiral Epichlorohydrin by Enantioselective Hydrolysis Reaction using Rhodosporidium toruloides (Phodosporidium toruloides의 광학선택적 가수분해활성을 이용한 Chiral Epichlorohydrin의 회분식 생산)

  • 이은열;이재화
    • KSBB Journal
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    • v.19 no.1
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    • pp.38-41
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    • 2004
  • Enantioselective hydrolysis for the producing chiral epichlorohydrin from its racemic substrate was investigated using epoxide hydrolase activity of Rhodosporidium toruloides SJ-4. The effects of reaction parameters including pH, temperature, initial substrate concentration on initial hydrolysis rate and enantioselectivity were analyzed and optimized. The addition of detergent, Tween 20, enhanced the hydrolysis rate and enantioselectivity. Chiral (R)-epichlorohydrin with high optical purity (>99% ee) and yield of 25% (theoretically 50% maximum yield) was obtained from its racemate of 20 mM.

A study on the Change of Hand of Chitosan Crosslinked Cotton Fabrics - Effect of Concentration of Epichlorohydrin and Chitosan - (키토산 가교처리된 면직물의 태 변화에 관한 연구 - 에피클로로히드린과 키토산 농도의 영향-)

  • Kim, Min-Ji;Park, Jung-Woo;Lee, Shin-Hee
    • Fashion & Textile Research Journal
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    • v.6 no.5
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    • pp.660-666
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    • 2004
  • This article describes the change of hand value of chitosan crosslinked cotton fabrics. The chitosan crosslinked cotton fabrics were manufactured by mercerizing process using epichlorohydrin(ECH) as crosslinkins agent, 2% aqueous acetic acid as a solvent of chitosan and ECH, and 20% aqueous sodium hydroxide as a mercerizing agent and crosslinking catalyst. Cotton fabrics were dipped in the mixed solution of chitosan and ECH, picked up by mangle, mercerized and crosslinked in NaOH solution, and finally wash and dry. Mechanical and physical properties of the chitosan crosslinked fabric were investigated using Kawabata Evaluation System(KES) and other instruments. Tensile energy and tensile strain were decreased with the increase of the concentration of chitosan. Tensile resilience, compression resilience bending rigidity, bending hysteresis, shear stiffness, shear hysteresis, coefficient of friction, geometrical roughness, compression linearity, compressional energy, and thickness were increased with the increase of the concentration of chitosan. On the other hand, bending rigidity, bending hysteresis, coefficient of friction, geometrical roughness, compressional resilience, and thickness were increased with the increase of the concentration of crosslinking agent(epichlorohydrin).

Synthesis of Glycidyl Azido Copolyetherdiol for Solid Propellant Polyurethane Binder (Glycidyl Azido Copolyetherdiol을 이용한 Polyurethane의 합성과 특성분석)

  • Shin, Bum-Sik;Lee, Bum-Jae;Park, Young-Chul;Hwang, Kab-Sung
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.11a
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    • pp.231-236
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    • 2008
  • The well-defined copolymers derived from Epichlorohydrin(ECH), Tetrahydrofuran(THF) were synthesized by Cationic ring-opening polymerization(CROP) with 1,4-Butandiol, a initiator, and $BF_3THF$ Complex, a catalyst via Activated monomer mechanism, which could lead to hydroxyl-terminated polyethers. The molecular weight of polymers were dependant on the ratio of [monomer]/[diol], Copolymer structures were controlled by monomers feed ratio, ECH and THF added. This polymers were functionalized from Chlorine group to Azide group using $S_N2$ reaction. Synthesized polymers were found to be as the prepolymer for polyurethane. Polyurethane was synthesized in the presence of N-100/IPDI mixture, a curing agent, and TPB(triphenyl bismuth)/MA(Maleic anhydride) mixture, a catalyst system. The curing behavior and mechanical properties of polyurethane after mixing with various prepolymer’s composition and the molecular weight were studied.

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Physical Property and Virtual Sewing Image of Lyocell treated with Epichlorohydrine for the fibrillation control

  • Park, Ji-Yang;Jeon, Dong-Won;Kim, Sin-Hee
    • Journal of Fashion Business
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    • v.12 no.6
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    • pp.46-60
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    • 2008
  • Lyocell is a regenerated cellulosic fiber manufactured by an environmentally friendly process. The major advantages of lyocell are the excellent drape forming property, the genuine bulkiness, smooth surface, and high dry/wet tenacities. However, one drawback of lyocell is its fibrillation property, which would degrade its aesthetic quality and lower the consumer satisfaction. In our previous studies, lyocell was treated with epichlorohydrin, a non-formalin based crosslinker, to reduce its fibrillation tendency. To investigate the changes of physical properties upon ECH-treatment, the hand characteristics of ECH-treated fabric were observed using KES-FB system and the 3D-virtual sewing image of the fabrics were obtained using 3D CAD simulation system in this study. Since epichlorohydrin(ECH) treatment was conducted in the alkaline medium, the weight reduction was observed in all treated lyocell. The treated lyocell became light, smooth and flexible in spite of ECH crosslinker application. LT and RT in tensile property upon the ECH treatment did not change significantly, however, EMT and WT in the tensile property increased. The significant decrease in bending rigidity was resulted in all ECH-treated lyocell, which is the result of the weight loss upon the alkali condition of ECH treatment. The bending rigidity increased again in the ECH 30% treated lyocell, however, the B value is still lower than the original. Therefore, the ECH-treated lyocell would be more stretchable and softer than the original. Shear rigidity was also decreased in all ECH-treated lyocell, which would result in more drape and body fitting when it is made as a garment. The ECH-treated fabric showed the softer smoother surface according to SMD value from KES evaluation. The virtual 3D sewing image of the ECH-treated lyocell did not show a significant change from that of the original except ECH 30% treated lyocell. ECH 30% treated lyocell showed a stiffer and more puckered image than the original.

Mechanical Properties and Degradability of Modified Starch and Polyethylene Blends (변성전분과 폴리에틸렌 혼합물의 물성 및 분해성 평가)

  • Jang, Si-Hoon;You, Young-Sun;Seo, Jong-Chul;Park, Su-Il
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.16 no.2_3
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    • pp.59-65
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    • 2010
  • Starch was modified with epichlorohydrin(ECH) to improve the miscibility with LDPE and LLDPE. Native starch or epichlorohydrin treated starch was mixed with grycerol and LDPE/LLDPE resin using a kneader and extruded using a single screw extruder to make pallets. The pallets were compression-molded at 145 into composite boards to evaluate their color, oxygen permeation, mechanical and thermal properties, and degradability under UV irradiation. Sheets with epichlorohydrin treated starch generally showed higher L-value than that of native starch blend sheets. The hunter b-values in both native starch blends and epichlorohydrin treated starch blends increased with Increasing starch contents. Tensile strength and percent elongation of sheets decreased with increasing starch contents. Tensile strength and percent elongation of sheets decreased with increasing starch contents. The degradability of blends under UV radiation increased with increasing starch contents in both blend types. The results represents that crosslinking of starch with epichlorohydrin may be a good method to improve miscibility of starch with petroleum-based materials.

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The mechanical and antimicrobial properties of chitosan crosslinked rayon fabric - Effect of chitosan and epichlorohydrin(ECH) concentration - (키토산 가교처리된 레이온 직물의 역학적특성과 항균성 - 에피클로로히드린과 키토산 농도의 영향 -)

  • Ahn, Jung-Mi;Kim, Min-Ji;Lee, Shin-Hee
    • Textile Coloration and Finishing
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    • v.18 no.6 s.91
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    • pp.16-24
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    • 2006
  • The purpose of this study is to improve the defects of chitosan crosslinked viscose rayon by ECH and to describe the change of hand of chitosan crosslinked viscose rayon fabrics. The chitosan crosslinked viscose rayon were manufactured by crosslinking process using ECH as crosslinking agent, 2 wt% aqueous acetic acid as a solvent of chitosan and ECH, and 20 wt% aqueous sodium hydroxide as crosslinking catalyst. Viscose rayon were first immersed in the pad bath of the mixed solution of chitosan and ECH, padded up to 100 wt% wet pick-up on weight of fiber(owf), precured on pin frames at $130^{\circ}C$ for 2 minutes, immersed in NaOH solution and finally wash and dry. Antimicrobial properties of the viscose rayon treated with chitosan were measured by the shake flask C.T.M. 0923 test method with staphylococcus aureus(ATCC 6538) as the microorganism. When the concentration of chitosan was increased chitosan crosslinked viscose rayon's LT, WT, B, 2HB and MIU were increased and G, 2HG, SMD, T and $T_m$ were decreased. On the other hand, WT, EM were decreased and RT was increased at $1{\times}10^{-2}M$ ECH. The optimum condition for crosslinking was that ECH concentration was between $1{\times}10^{-2}M\;and\;5{\times}10^{-2}M$. Antimicrobial effects of rayon fabric treated with chitosan was excellent.

A Study on the Change of Hand of Chitosan Crosslinked Cotton Fabrics(II) - Effect of Concentration and Molecular Weight of Chitosan - (키토산 가교 처리된 면직물의 태 변화에 관한 연구(II) - 키토산 농도 및 분자량의 영향 -)

  • Kim, Min-Ji;Lee, Shin-Hee
    • Fashion & Textile Research Journal
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    • v.7 no.4
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    • pp.439-444
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    • 2005
  • This article describes the change in the hand value of chitosan-crosslinked cotton fabrics. The chitosan-crosslinked cotton fabrics were manufactured by mercerizing process using epichlorohydrin(ECH), 2% aqueous acetic acid and 20% aqueous sodium hydroxide. It proposed that the crosslinking and mercerizing were performed with the mixture of four different molecular weight chitosan and ECH in a single step. Cotton fabrics were dipped in the mixed solution of chitosan and ECH, picked up by mangle roller, pre-dried at $130^{\circ}C$, mercerized and crosslinked in NaOH solution and finally washed and dried. Mechanical and physical properties of the chitosan crosslinked fabric were measured on concentration and molecular weight by Kawabata Evaluation System(KES) and other instruments. As the concentration of chitosan solution increased, LT, WT, B, 2HB were increased. WT, B, 2HB, MIU, SMD, $T_0$, $T_m$ were decreased when chitosan was depolymerized. On the other hand, RT was increased when chitosan was depolymerized.

A Study on The Optimization of Pre-treatment for the Brine Wastewater from the Epoxy-resin Process by the Coagulation and Sedimentation Reactions (에폭시수지 생산 공정에서 발생되는 brine 폐수의 전처리를 위한 응집 및 침전 반응의 최적화 연구)

  • Cho, Wook Sang;Lee, Eun Young;Kang, Seong Wook;Lee, Jang Su;Jin, Su Ik
    • Clean Technology
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    • v.11 no.2
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    • pp.57-67
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    • 2005
  • Epoxy resins are produced by the dehydro condensated reaction with ECH (Epichlorohydrin) and BPA(Bisphenol-A) as raw reactants under sodium hydroxide(NaOH) as a catalyst, and from this reaction, salted water named of brine, which contains ECH derivatives in condition of emulsion as likely as glycidol and polymer resins, is produced as an undesired side product. This brine water is alkaline wastewater and causes process fouling problems by plugging and chemically depositing polymer particles on the surface of inner wall of reactors and pipes, and decreases the biodegradable efficiency in the wastewater process. In this study, the optimization of coagulation and sediment reactions, using inorganic and organic polymer coagulants, were performed to remove the causes occurring the process fouling phenomena. And also, based on this study, the methodologies applicable to the commercial processes including economical analysis were presented.

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Time-course response of epichlorohydrin on epididymal histopathology in rats

  • Kim, Kang-Hyeon;Shin, In-Sik;Lim, Jeong-Hyeon;Kim, Sung-Hwan;Park, Na-Hyeong;Moon, Changjong;Kim, Sung-Ho;Shin, Dong-Ho;Kim, Jong-Choon
    • Korean Journal of Veterinary Research
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    • v.49 no.4
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    • pp.279-284
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    • 2009
  • This research aimed to investigate the time-course effect of epichlorohydrin (ECH) on epididymal histopathology in Sprague-Dawley rats. Twenty-four male rats were randomly assigned to four groups with 6 rats in each group and were administered a single oral dose of ECH (70 mg/kg) or its vehicle. Six animals each were sacrificed on days 0 (control), 1, 2, and 7 after treatment. During the study period, clinical signs, body weights, reproductive organ weights, testicular spermatid count, epididymal sperm count, motility and morphology, and histopathology were examined. No treatmentrelated effects on body weights and reproductive organ weights were noted at any time point. On the contrary, sperm motility decreased slightly on days 1 and 2 after treatment and then decreased significantly on day 7 after treatment. The first signs of histological changes were the appearance of cell debris in the ducts and vacuolization of the epithelial cells observed in the proximal caput epididymis on day 1 after treatment. The incidences and grades of the histological changes including cell debris in the ducts, epithelial vacuolization, oligospermia, and epithelial disruption increased on day 2 and then decreased slightly on day 7 after treatment. These results show that a single oral dose of 70 mg/kg ECH to male rats results in cell debris in the ducts and vacuolization of the epithelial cells in the proximal caput epididymis, followed by reversible oligospermia, epithelial disruption, and decreased sperm motility.

Synthesis of Characterization of Poly(alkylene oxide) Copolyols by Catioinc Ring Opening Polymerization and Their Azide Functionalized Copolyols (양이온 개환중합에 의한 폴리알킬렌 옥사이드 코폴리올의 합성과 아지드화 코폴리올의 특성 연구)

  • Lee, Jae-Myung;Seol, Yang-Ho;Kwon, Jung-Ok;Jin, Yong-Hyun;Noh, Si-Tae
    • Applied Chemistry for Engineering
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    • v.31 no.3
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    • pp.267-276
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    • 2020
  • Poly(epichlorohydrin) copolyol series (PECH copolyols) were synthesized via cationic ring-opening copolymerization (ROCP) of oxirane-based monomers and effects of reaction temperature, solvent type, and initiator were studied. As a comonomer, two types of alkylene oxides were used, and polymerization conditions were conducted both with diethylene glycol (DEG) as an initiator in methylene chloride (MC) solvent and tripropylene glycol (TPG) in toluene solvent. In order to induce the active monomer (AM) mechanism in the ring-opening copolymerization reaction, the monomer was injected by an incremental monomer addition (IMA) method using a syringe pump, and the polymerization was performed at -5 ℃. PECH copolyol, a synthesized ephichorohydrin (ECH)-based copolyol, was converted to glycidyl azide-based energy-containing copolyol (GAP copolyol) by azadizing the ECH unit through a substitution reaction. It was confirmed that the synthesized azide copolyol had little effects on changes of the solvent and the initiator. Also, the molecular weight increased 500 after the azide reaction, thereby the GAP copolyol was polymerized as designed. As the content of the comonomer increased, both the Tg and viscosity tended to decrease due to the influence of the alkyl chain length. It is possible to fundamentally prevent CH3N3 amount produced in the azide reaction process, and it is expected that a large-scale process could be achievable.