• Title/Summary/Keyword: 용매 분해

Search Result 859, Processing Time 0.021 seconds

A Study on Synthesis of Acrylic Pressure Sensitive Adhesive for Polarizer Film by Solution Polymerization (용액중합에 의한 편광필름용 아크릴 점착제의 합성에 관한 연구)

  • Lim, Chang-Hyuk;Jung, Young-Jae;Cho, Ur-Ryong
    • Elastomers and Composites
    • /
    • v.44 no.2
    • /
    • pp.175-181
    • /
    • 2009
  • The solution polymerization was conducted to synthesize pressure sensitive adhesive for polarizer film using acrylic monomers. 2-Ethylhexyl acrylate, butyl acrylate, acrylic acid were used as acrylic monomers, benzoyl peroxide as initiator, ethyl acetate as solvent. The ratio of monomers was 2-ethylhexyl acrylate: butyl acrylate: acrylic acid = 25:50:3.6 reflecting $-40^{\circ}C$ of glass transition temperature in the pressure sensitive adhesive. The amount of initiator was determined as 0.09% to monomer considering wetting power and initial tackiness. The ratio of monomer to solvent was determined as 1:1.7 considering wetting power and transmissivity. The transmissivity of pressure sensitive adhesive increased with decreasing both viscosity and molecular weight due to reducing of refractive index by low entanglement between molecules. In the measurement of pot life, it was found that the storage stability was good at 1:1.7 of monomer: solvent without large change of viscosity during 200 min.

Characteristics of Hericium erinaceus and its Extracts (노루궁뎅이 버섯 및 추출물의 특성)

  • 최미애;박난영;우승미;정용진;신승렬
    • Food Science and Preservation
    • /
    • v.10 no.4
    • /
    • pp.560-564
    • /
    • 2003
  • The functional properties of Hericium erinaceus were analyzed. The crude protein content was 8.01%. free sugars were mainly composed of glucose(47.09 mg%) and fructose(34.65 mg%), but sucrose and maltose were not detected. The free amino acids were mainly glutamic acid(1,468.12 mg%), alanine(716.07 mg%) and threonine(643.95 mg%) in Hericium erinaceus. It doesn't difference between water and ethanol extract on soluble solid content. Comparing minerals of extracts from Hericium erinaceus, water extract showed higher contents than ethanol extract except for I This tendency is similar to superoxide scavening activity and electron donating activity. But phenolic compounds, ethanol extract was higher than water extract. In comparison of water and ethanol extract of Hericium erinaceus, as a whole water extract was excellent.

The characteristics of a fine O/W emulsion by non-aqueous method (비수유화법에 의한 미세 o/w에멀젼의 특성)

  • Lee, Seong-Jun;Yun, Myeong-Seok;Gang, Se-Hun
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.21 no.1
    • /
    • pp.19-37
    • /
    • 1995
  • A fine oil -in-water (O/W) emulsion using non-aqueous emulsification technique was developed. And the behaviors of POE(25)octyldodecyl ether in non-aqueous polyol/oil systems were studied by observing the surface tension, interfacial tension, turbidity and transition temperature. It was found that POE(25)octyldodecy1 ether hardly existed as the micelle in the non-aqueous polyol system while, in water, it formed micelles very easily. So, when a polyol, like glycerine in which POE(25)octyldodecyl ether has a poor solubility, was added, POE(25)octyldodecyl ether moved to the surface. After saturated at surface, POE(25)octyldodecyl ether began to precitate. The mean particle size of the final emulsion was 230nm. Also, the emulsion system was stable at 0$^{\circ}C$, 25$^{\circ}C$, 40$^{\circ}C$, 50 $^{\circ}C$ and freeze-thaw cycle chamber for a month, while a conventional emulsion system was unstable. It is concluded that, by pertinent combination of polyols, we can improve the adsorption efficiency of surfactant.

  • PDF

Changes of Total Polyphenol Content and Electron Donating Ability of Aster glehni Extracts with Different Microwave-assisted Extraction Conditions (마이크로웨이브 추출조건에 따른 섬쑥부쟁이 추출물의 총 폴리페놀 함량 및 전자공여 작용 변화)

  • Kim, Hyun-Ku;Kwon, Young-Joo;Kim, Kong-Hwan;Jeong, Yoon-Hwa
    • Korean Journal of Food Science and Technology
    • /
    • v.32 no.5
    • /
    • pp.1022-1028
    • /
    • 2000
  • Aster glehni was extracted by microwave-assisted extraction(MAE) and reflux extraction(RE) methods and their extraction efficiencies were compared. A considerable reduction in extraction time was achieved by MAE. When 70% methanol, 50% methanol, 70% ethanol, or 50% ethanol was used, MAE extract contained nearly same amounts of soluble solid and total polyphenol contents as obtained by RE. The optimum MAE conditions for the extraction of Aster glehni were $120{\sim}150$ watts of microwave energy and $4{\sim}8$ minutes of extraction time. No significant changes were found in electron donating ability(EDA) over the variation of microwave energy or extraction time. The use of diluted methanol or ethanol resulted in improving extraction yield(24%), total polyphenol content(2.6%) and EDA(60%).

  • PDF

Quality Properties of Oak Mushroom (Lentinus edodes) Based on Extraction Conditions and Enzyme Treatment (표고버섯(Lentinus edodes)의 추출조건 및 효소처리에 따른 품질 특성)

  • Park, Nan-Young;Jeong, Yong-Jin
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.35 no.9
    • /
    • pp.1273-1279
    • /
    • 2006
  • The quality properties of oak mushroom were investigated using extraction conditions and enzyme treatments. The physiochemical properties were excellent at the extraction temperatures of $20^{\circ}C\;and\;40^{\circ}C$. The quality was increased as the extraction time increased but was best at the extraction time of 10 hr. The physiochemical properties such as soluble solid, reducing sugar and crude protein contents were best at the solvent ratio of 1:100 (w/v) so that it was set at 1:100. Thus, enzyme treatment was done at $50^{\circ}C$ for 2 hr with the solvent ratio of 1:100. The result showed that the best quality was shown using 0.2% protease and 0.2% cellulase. With the enzyme treatment, the essential amino acid contents increased by two folds but no difference was shown in $\beta-glucan$ content.

Reductive Degradation of hexachloroethane by using Iron Minerals: Kinetics studies (철 광물에 의한 헥사클로에탄의 환원적 분해: 반응 속도 연구)

  • Kim, Sung-Kuk;Park, Sang-Won
    • Journal of Soil and Groundwater Environment
    • /
    • v.9 no.2
    • /
    • pp.20-27
    • /
    • 2004
  • Kinetic characteristics dependent on several factors such as iron mineral and organic solvents were investigated. When F $e^{0}$ , FeS and Fe $S_2$ were used as mediators, minerals affecting reaction rate were in the following order : $Fe_{0}$ 0/ > FeS > $FeS_2$ when in contact $C_2$C $l_{6}$ . The more chloride substituted, the higher reaction rate were observed. The reaction rates were dependent on pH, shaking rate, temperature and specific surface area. 1, 10-phenanthroline and EDTA degradation rates were fast, indicating that they adsorbed on the surface of the iron which makes the electron transfer reaction easy. Nitrate which has $\pi$* orbital of molecular can increase electron transfer rate because it is delocalized in its entity. The reaction rates were not affected by hydroquinone. Degradation rates were much enhanced with naturally occurring kaolinite because of the surface corrosion of Fe mineral. However, The reaction rate was not affected by F $e^{2+}$ or S $O_4$$^{2-}$ presented in solution.n.

Quality Characteristics of Domestic Strong Wheat Flour (시판 강력분 우리밀의 품질 특성)

  • Kwak, Han Sub;Kim, Mi Jeong;Kim, Oui-Woung;Kim, Sang Sook
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.46 no.5
    • /
    • pp.616-621
    • /
    • 2017
  • The objective of this study was to investigate the physicochemical properties of domestic strong wheat flour (DSWF). Three commercial DSWFs (D1, D2, and D3) were compared with imported strong wheat flour (ISWF). DSWFs had higher moisture content, crude protein content, lightness, and whiteness than ISWF. DSWFs showed lower solvent retention capacity and water absorption index than ISWF. DSWFs also showed significantly higher water solubility index than ISWF (P<0.05). Setback values by rapid visco analysis were significantly higher in D1 and D2 than in ISWF and D3, which means ISWF and D3 were better in retarding retrogradation. Differential scanning calorimetry results showed that ISWF required 6.2 J/g of energy for phase transition, whereas DSWFs needed 6.67~7.13 J/g. The farinograph results showed that ISWF had higher water absorption, longer dough stability time, and significantly higher softening of dough at 20 min than DSWF (P<0.05). Dough resistance and extensibility were higher in ISWF than in DSWFs.

Competitive Solvent Extraction of Alkali Metal Ions with Azacrown Ether Phosphinic Acids (아자크라운에테르포스피닉산에 의한 알카리금속이온의 경쟁용매추출)

  • Nam, Chong-Woo;Chung, Yeong-Jin;Yang, Il-Woo
    • Applied Chemistry for Engineering
    • /
    • v.3 no.2
    • /
    • pp.266-272
    • /
    • 1992
  • Azacrownoalkyl phenylphosphinic acids were synthesized and their competitive solvent extraction characteristics from water to chloroform layer were investigated. Phosphinic acids were synthesized in good yields by one step reaction of phenylphosphinate, aldehyde, and monoazacrown ether and then basic hydrolysis of the resulting phosphinate dsters. These complexing agents revealed a wide effective pH range in extraction of alkali metal ions from water to the organic phase and total metal ion loading at pH 11 was about 75%. The selectivity of the cation extraction was determined mainly by the cavity size of the azacrown ethers, showing $Na^+$ >> $K^+$ > $Rb^+$ > $Li^+$ > $Cs^+$ for the alkyl phenylphosphinic acid ${\underline{2}}$, containing monoaza-15-crown-5 and $K^+$ >> $Rb^+$ > $Na^+$ > $Cs^+$ > $Li^+$ for the alkyl phenylphosphinic acid, ${\underline{3}}$, containing monoaza-18-crown-6 moiety. Applicable pH range of these azacrown ether phosphinic acids in solvent extraction of alkali metal cations was wider than a crownether carboxylic acid with similar selectivity, showing considerable amount of metal ion loading in slightly acidic or neutral media.

  • PDF

Antibacterial Activity of Sea-mustard, Laminaria japonica Extracts on the Cariogenic Bacteria, Streptococcus mutans (충치균 (Streptococcus mutans)에 대한 다시마 추출물의 항균활성)

  • Kim Ji Hoe;Lee Doo Seog;Lim Chi Won;Park Hee Yeon;Park Jeong Heum
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.35 no.2
    • /
    • pp.191-195
    • /
    • 2002
  • In previous reports the authors have screened the inhibition effects of marine algae extracts on halitosis, and demonstrated that a brown algae, Eisenia bicyclis (' Daehwang') possess not only strong deodorant effect bug also considerable anticariogenic activities. In this study, we screened antibacterial effects of various marine algae, and measured minimum inhibitory concentration (MIC) value of them against mutans streptococci in vitro. Among the 27 species of marine algae, $80\%$ ethanol extract of dried sea-mustard, Laminaria japonica ('Dasima') showed the strongest inhibition activity against Streptococcus mutans KCTC 3300. The extracts of Ulva lactuca ('Galparae'), Codium fragile ('Cheonggak'), Ecklonia cava ('Gamtae'), E. stolonifera ('Gompi') and Undalia Pinnatifida ('Miyeok') showed slightly weaker inhibitory potency than L. japonica. Differences of MIC values in $80\%$ ethanol extract of some species of marine algae were observed depending on test bacterial species, i.e., S. mutans KCTC 3300 or S. sobrinus KCTC 3307. Eighty percent ethanol extract of dried L japonica was fractionated with diethyl ether, chloroform, ethyl acetate, n-buthanol and water successively, The ether-soluble fraction had inhibitory effect on S. mutans KCTC 3300, however the inhibitory effects were not found in the other fractions. The MIC values of $80\%$ ethanol extract and ether fraction were 180 and 105 $\mu$g/mL respectively, while no significant inhibition activity of water-soluble fraction was found even when the fraction was added up to 5,500 $\mu$g/mL.

Content Comparison of Proximate Compositions, Various Solvent Extracts and Saponins in Root, Leaf and Stem of Panax Ginseng (인삼의 근, 엽 및 경의 일반성분, 용매별 엑기스 및 사포닌 함량 비교)

  • 김석창;최강주
    • Journal of Ginseng Research
    • /
    • v.11 no.2
    • /
    • pp.118-122
    • /
    • 1987
  • This study was carried out to investigate the effective components, especially saponins, in aerial parts of Panax ginseng. The contents of methanol and ethanol extracts in ginseng leaf were 35.9% and 27.3%, much higher than 15.4% and 8.37% in ginseng root and 21.7% and 16.3% in ginseng stem. And ginseng stem showed as high content of crude fiber as 39.2% which is very high compared with other two parts of ginseng. The contents of total crude saponin were 4.78%, 2.38% and 19.58% in ginseng root, stem and leaf, respectively. In ginseng leaf seven root ginseno-sides-ginsenoside-Rgl(3.32%), -Re(3.24%), -Rd(2.32 %), -Rc(0.65%), -Rb2(0.92%), -Rbl(0.29%), and -Rf(0.11%)-were analyzed by HPLC, Seven gisneno- sides-ginsenoside-Rgl(0.28%), -Re(0.3%), -Rd(0.05%), -Rf(0.01%), -Rc(trace), -Rb2(trace) and -Rbl(trace)-were detected in ginseng stem. Ginseng leaf contained high percentage of saponin and especially of ginsenoside-Rgl, -Re and -Rd. Therefore, ginseng leaf was good resources for ginsenoside-Rgl, -Re and -Rd.

  • PDF