• Journal of the Korean Wood Science and Technology
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• 제22권3호
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• pp.45-50
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• 1994

This experiment was to investigate the effects of UV radiation and chemical treatments on the color difference in antioxidant (Tris(2,4-di-t-butyl phenoxy) phosphite)-containing polyurethane coats. The results obtained were summerized as follows: 1. The color difference increased as the exposure time of UV radiation increases, but decreased as addition level of antioxidant increaes. 2. After 400 hours exposure to UV radiation, the color difference respectively showed 6.13 and 5.94 at 0.7 % and 1.0 % addition level but appeared more severe below 0.7 % addition level. Thus, antioxidant prevented discoloration effectively. 3. The color difference of films by chemical treatments increased after 8 hours. Color difference of films treated with 5 % acetic acid($CH_3COOH$), 30 % ethyl alchol ($CH_3CH_2OH$) showed 7.31 and 7.30 respectively. 1 % sodium hydroxide treatment showed 1.86 color difference after 8 hours.

• Journal of Electrochemical Science and Technology
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• 제6권4호
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• pp.116-120
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• 2015

Lithium diffusivity of fluorine-free and -doped tin-nickel (Sn-Ni) film model electrodes with improved interfacial (solid electrolyte interphase (SEI)) stability has been determined, utilizing variable rate cyclic voltammetry (CV). The method for interfacial stabilization comprises fluorine-doping on the electrode together with the use of electrolyte including fluorinated ethylene carbonate (FEC) solvent and trimethyl phosphite additive. It is found that lithium diffusivity of Sn is largely dependent on the fluorine-doping on the Sn-Ni electrode and interfacial stability. Lithium diffusivity of fluorine-doped electrode is one order higher than that of fluorine-free electrode, which is ascribed to the enhanced electrical conductivity and interfacial stabilization effect.

• Bulletin of the Korean Chemical Society
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• 제18권8호
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• pp.824-827
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• 1997

Bis(ethylene)rhodium(Ⅰ) chloride dimer reacted with vinylcyclopropane to give σ,η3-allylrhodium(Ⅲ) complex 3. Complex 3 underwent C-C bond cleavage of 8-quinolinyl ethyl ketone 11, to form η3-1,3-dimethylallylrhodium(Ⅲ) complex 8, which was reductively eliminated by trimethyl phosphite to give 8-quinolinyl-1-methylbut-2-enyl ketone (10). More sterically hindered 8-quinolinyl alkyl ketones were allowed to react with complex 3 to afford corresponding alkenes as well as a mixture of complex 8 and η3-1-ethylallyl rhodium(Ⅲ) complex 19, identified as 10 and 8-quinolinyl-pent-2-enyl ketone (20) after reductive elimination. 8-Quinolinyl alkyl ketone bearing a sterically hindered alkyl group showed less reactivity for C-C bond cleavage and higher 20/10 ratio compared with those having a less sterically hindered alkyl group, such as 8-quinolinyl ethyl ketone (11).

• Bulletin of the Korean Chemical Society
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• 제22권6호
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• pp.553-558
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• 2001

A stereoselective synthesis of $1\beta-aminocarbapenems$ (11a-c) starting from-4-acetoxy-2-axetidinone derivative 4 is described. 4-Acetoxy-2-azetidinone derivative (4) was reacted with lithium enolate of benzophenone limine of glycine phenyl ester (5f) to give alkylated product (R)-6f in good yield with high diastereoselectivity. The alkylated procudt (R)-6f was transformed to thioesters (7a-c) by transesterification with thiols, Thioesters (7a-c) were converted to their oxalimides (8a-c), followed by the phosphite-mediated reductive cyclization to give carbapenems (9a-c). Removal of all protecting groups of carbapenems (9a-c) afforded $1\beta-aminocarbapenems$ (11a-c).

• Macromolecular Research
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• 제17권11호
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• pp.901-906
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• 2009

Several aromatic optically active polyamides (PA)s were synthesized from 5-(2-phthalimidiylpropanoylamino)isophthalic acid with various aromatic diamines via direct polycondensation with triphenyl phosphite and pyridine in the presence of calcium chloride and N-methyl-2-pyrrolidone under microwave irradiation and conventional heating conditions. Under the optimized conditions, the reaction mixture was irradiated for 2 min. with a 100% irradiation power (900 W). The resulting polymers were obtained in high yield and moderate inherent viscosity ranging from 0.35 to 0.60 dL/g. All synthesized polymers showed excellent solubility in amide-type solvents. Thermogravimetric analysis revealed a 10% weight loss temperature and char yield at $600^{\circ}C$ in a nitrogen atmosphere of > $350^{\circ}C$ and > 58%, respectively, which suggests that the resulting PAs have good thermal stability.

• 전기화학회지
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• 제20권2호
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• pp.34-40
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• 2017

높은 출력의 장점을 가지는 전기이중층 커패시터 (EDLC: electric double layer capacitors)는 이차 전지와 더불어 차세대 에너지 저장장치로서 각광받고 있으나 낮은 에너지 밀도로 인해 그 사용처가 제한적이다. 본 연구에서는 EDLC의 에너지 밀도 향상 방법 중의 하나인 고전압화 구현 시 적합한 전해액을 연구하기 위해 AN (acetonitrile)용매에 $SBP-BF_4$ (spirobipyrrolidinium tetrafluoroborate), $TEA-BF_4$ (tetraethylammonium tetraflouroborate), $EMI-BF_4$ (1-ethyl-3-methylimidazolium tetrafluoroborate)의 세가지 염을 각각 선정하여 다양한 전해액의 조성에 따른 전기화학 특성을 비교 평가하였다. LSV (linear sweep voltammetry)측정에서 1.5M SBP-BF4/AN 전해액은 넓은 전위영역에서 안정함을 보였고, 고전압의 환경 (3.0 V 이상)에서 다른 조합의 전해액들과 비교하여 가장 우수한 전기화학적 성능을 보였다. 또한, 장기적으로 안정적인 성능을 유지하기 위해 리튬이온전지시스템에서 기능성 첨가제 효과가 입증된 TMSP (tris(trimethylsilyl)phosphite) 첨가제를 적용 했을 때 고전압의 환경 (3.3 V)에서 10,000 cycle 후 93%의 높은 용량 유지율을 얻을 수 있었다.

• 농약과학회지
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• 제3권1호
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• pp.20-28
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• 1999

Chloronicotinyl 유도체의 기본 골격인 3-pyridylmethylamine의 amine기를 phosphite group으로 치환하여 chloronicotinyl 유도체를 합성하였고, 이들의 살충활성과 살균활성을 확인하였다. 살충활성 검정 결과, 500 ppm 에서 phosphonate에 methyl기와 butyl기가 치환된 compound 4와 2개의 butyl, 2,2,2-trifluorotehtyl, 2-ethylhexyl, phenyl기가 치환된 compound 5, 6, 7, 8이 벼멸구에 대해서 90%의 살충활성을 나타내었다. 그러나 이들 화합물들은 배추좀나방과 두점박이응애에 대해서는 낮은 살충활성을 나타내었으며, phosphonate에 halogen이나 heterocycle이 치환된 compound $10{\sim}21$에서도 벼멸구, 배추좀나방, 담배거세미나방, 두점박이응애, 복숭아혹진딧물에 대하여 거의 살충활성을 나타내지 않았다. Chloronicotinyl 유도체의 벼도열병균, 벼문고병균, 오이잿빛 곰팡이병균, 토마토역병균, 밀녹병균, 보리흰가루병균에 대한 살균활성을 검정한 결과, 10 ppm에서 phosphonate에 butyl기와 4-nitrophenyl기가 치환된 compound 10이 벼도열병균에 대해 86%의 살균활성을 보였다. 인 함유 chloronicotinyl 유도체들 중 일부가 높은 살균활성을 나타낸다는 것은 이 유도체들이 신규 살균제로 개발될 가능성이 있다는 것을 시사하고 있다.

• Molecular & Cellular Toxicology
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• 제2권2호
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• pp.89-96
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• 2006

The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is of great concern at present. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of chemicals that possibly threaten the public health. In this respect, to regulate and to evaluate the chemical hazard will be important to environment and human health. The clastogenicity of 11 synthetic chemicals was evaluated in Chinese hamster lung fibroblast cells in vitro. 1-Chloro-3-bromopropane CAS No. 109-70-6) induced chromosomal aberrations with significance at the concentration of $185.0\;{\mu}g/mL\;and\;1,600\;{\mu}g/mL$ both in the presence and absence of metabolic activation system, respectively. Triphenyl phosphite (CAS No. 101-02-0), which is one of the most cytotoxic chemical among 11 chemicals tested revealed no clastogenicity in the range of $95.0-4.9\;{\mu}g/mL$ both in the presence and absence of metabolic activation system. From the results of chromosomal aberration assay with 11 synthetic chemicals in Chinese hamster lung cells in vitro, 1-chloro-3-bromopropane revealed a positive clastogenic result in this study.

• 대한화학회지
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• 제15권5호
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• pp.275-280
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• 1971

Six previously unreported N-acylated-DL-1-amino alkyl phosphonic acids were prepared; N-Acetyl-DL-1-amino-3-methyl butyl phosphonic acidN-Benzoyl-DL-1-amino-2-methyl propyl phosphonic acidN-Benzoyl-DL-1-amino-3-methyl butyl phosphonic acidN-Benzoyl-DL-1-amino-2-methyl butyl phosphonic acidN-Acetyl-DL-1-amino-2-methyl propyl phosphonic acidN-Acetyl-DL-1-amino-2-methyl butyl phosphonic acidThe first four compounds were characterized, and the last two compounds were obtained in the crude oil state. The above three DL-1-amino-alkyl phosphonic acid were synthesized from iso-valeric acid, iso-caproic acid and ${\beta}$-methyl valeric acid using Hell-Volhard-Zelinsky reaction, the condensation reaction with triethyl-phosphite and the modified Curtius Reaction. Iso-caproic acid and ${\beta$-methyl valeric acid were prepared by the conventional methods.

• 한국응용과학기술학회지
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• 제27권2호
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• pp.129-136
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• 2010

A series of noble poly(amide-imide)s and copoly(amide-imide)s bearing 1,2-bis(4-phenoxy)benzene units were synthesized by the direct polycondensation of 1,2-bis(4-trimellitimidophenoxy)benzene[1,2-PTPB] with a combination of commercially available aromatic diamines and diacids such as m-phenylene diamine, p-phenylene diamine(PPD), isophthalic acid and terephthalic acid(TA) in N-methyl-2-pyrrolidone(NMP) using triphenyl phosphite and pyridine as a condensing agent in the presence of dehydrating agent ($CaCl_2$). The resulting polymers had inherent viscosities in the range of 0.37~0.78 dL/g and most of them were soluble m common organic solvents including NMP, dimethylacetamide, dimethylsulfoxide, dimethylformamide, and m-cresol. Wide-angle X-ray diffractograms revealed that the copoly(amide-imide) derived from PPD with mixed acids of 1,2-BTPB and TA, showed crystalline nature, whereas all of the other polymers were found to be amorphous. The glass transition temperatures of the polymers occurred over the temperature range of $270{\sim}323^{\circ}C$ in their differential scanning calorimetry curves and their 10% weight loss temperature, determined by thermogravimetric analysis in air and nitrogen atmosphere, were in the range $465{\sim}535^{\circ}C$, $500{\sim}550^{\circ}C$, respectively, indicating their good thermal stability.