• 제목/요약/키워드: Polyethyleneglycol

검색결과 65건 처리시간 0.026초

Epoxy-Methacrylate Prepolymer의 合成 및 그의 單位體 混合物의 電子線硬化 (Preparation of Epoxy-Methacrylate Prepolymer and Electron Beam Curing of Its Mixture with Monomers)

  • 변형직;박완빈;김기엽;최규석
    • 대한화학회지
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    • 제21권4호
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    • pp.284-292
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    • 1977
  • 메타크릴酸과 diglycidyl ether 型 低分子量의 에폭시樹脂로부터 에폭시樹脂의 dimethacrylate를 合成하였으며 이 prepolymer와 단위체인 스티렌 및 polyethyleneglycol dimethacrylate 混合物의 電子線硬化에 關하여 檢討하였다. 에스테르化反應은 메타크릴酸에 對하여 約 250∼300ppm以上의 hydroquinone과 $1{\%}$(wt) 以下의 triethanolamine의 添加로서 거의 定量的으로 進行되었다. 空氣中에서 행한 硬化에 있어서는 단위체 濃度10 ∼ $30{\%}$에서 最高의 겔分率을 나타내었으며 겔化速度는 prepolymer의 未反應 에폭시基와 酸의 存在에 의하여 減少되었고 polyethyleneglycol dimethacrylate內의 polyethyleneglycol의 重合度가 增加함에 따라 增加하였다. 窒氣中과 空氣中에서 겔化速度는 별다른 差異가 없었으나 生成物 性質의 差異로 보아 硬化時의 酸素의 影響은 상당히 컸으며 polyethyleneglycol dimethacrylate類를 단위체로 使用時는 더욱 그러하였다.

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The Isosteric Heats of Adsorption of Amines on Paraffin and Polyethyleneglycol

  • 손종락;김종택
    • 대한화학회지
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    • 제16권4호
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    • pp.208-213
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    • 1972
  • Isostric heats of adsorption of amines on paraffin and polyethyleneglycol were measured by gas chromatography. Value with polyethyleneglycol were significantly higher than those with paraffin due to the N-H...O bonding. The contribution of C-H...O bonding to the isosoteric heats of adsorption was negligible. The additional heats of adsorption observed as the sample size increased also increased as the number of amino hydrogen atoms decreased. This tendency was more significant with polyethyleneglycol indicating that strong directing force of amino hydrogen of primary and secondary amines to the surface hinder lateral attractive interaction which could be favored with free orientation.

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한우에 있어서 PEG에 용해시킨 Folltropin-V의 1회 피하주사에 의한 다배란 유기 (Superovulation in Korea Cattle with a Single Subcutaneous Injection of Folltropin-V Dissolved in Polyethyleneglycol)

  • 임석기;우제석;전기준;장선식;강수원;윤상기;손동수
    • 한국수정란이식학회지
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    • 제13권3호
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    • pp.207-212
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    • 1998
  • 본 연구는 한우에 있어서 다배란처리에 의한 체내 정상수정란의 생산효율을 극대화하기 위하여 PEG에 용해한 FSH의 1회 피하주사 방법이 현재 사용하고 있는 1일 2회 4일간 근육 주사방법을 대체할 수 있는지를 결정하기 위하여 실시하였다. 연구결과 다회 근육주사 방법과 비교하여 1회 피하주사 방법이 황체수, 총 회수란수 및 이식가능 수정란수에 있어서 현저히 증가 (P〈0.05)하였다. 따라서 한우에 있어서 PEG에 용해시킨 Folltropin-V의 1회 피하주사 방법이 효과적이라고 사료된다.

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Poly(BMA-co-PEGMA) Microsphere의 합성 및 특성 (Synthesis and Properties of Poly(BMA-co-PEGMA) Microspheres)

  • 전용진;조석형;이건직
    • 한국산학기술학회논문지
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    • 제14권10호
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    • pp.5299-5303
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    • 2013
  • Poly(butyl methacrylate-co-polyethyleneglycol methacrylate)(Poly(BMA-co-PEGMA)) microsphere은 침전중합법으로 에탄올 용액에서 제조하였으며 마이크로스페어의 입자 크기는 모노머인 BMA와 PEGMA의 농도조건에 따라 140-210nm까지 조절 할 수 있었다. PEGMA의 농도가 증가할 수록 마이크로스페어의 크기가 작아지는 반면 BMA의 농도가 증가하면 마이크로스페어의 입자크기가 증가하였다.

Preparation of Crack-free HTS YBCO Films by EPD Method

  • Soh, Dea-Wha;Li Yingmei;Nataly Korobova
    • Transactions on Electrical and Electronic Materials
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    • 제4권5호
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    • pp.6-9
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    • 2003
  • Electrophoretic deposition (EPD) of alcohol YBCO suspensions on the Ag wire electrode is studied. Polyethyleneglycol was coordinated to a structure formed by the EPD process with YBCO particles. The d.c electric fields of 200-300 V/cm are applied for 1-10 min. The optimal condition for the EPD allows modifying the properties and microstructure of the deposited films. Superconducting coatings with nanometer-sized pores and a preferred orientation along the caxis were prepared from the result with chemically modified precursor solution. In contrast, YBCO coatings of submicrometer-sized pores and randomly orientated grains were prepared from the solution without PEG.

Fusarium of oxysporum의 원형질체 융합과 polygalacturonase의 활성 (Protoplast Fusion of Fusarium oxysporum and activity of polygalacturonase)

  • 하경란;민병례
    • 한국균학회지
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    • 제21권3호
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    • pp.195-199
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    • 1993
  • Fusarium oxysporum을 재료로 하여 polygalacturonase 활성능이 좋은 우량 균주를 개발하기 위하여 돌연변이주와 원형질체융합주를 선별하였다. MNNG를 처리하여 6개의 영양요구성 돌연변이주를 유도하였다. 세포벽 분해효소로는 driselase를 이용하고 삼투안정제로 0.6M KCI을 처리하여 돌연변이체로부터 원형질체를 얻었다. polyethyleneglycol 8,000과 $CaCl_2$를 이용하여 영양요구성 돌연변이체의 원형질체 사이에 융합을 시도하여 1개의 융합주를 얻었으며 융합률은 $5.0{\times}10^{-3}$이었다. polygalacturonase 활성도를 수정된 DNS법을 이용하여 측정하였다. 결과적으로, 선별된 융합주와 돌연변이주의 polygalacturonase 활성은 모균주와 비교하여 약 1.5배에서 3.5배가량 증가하였으며 그 중에서도 mutant Fx-2가 가장 높은 활성도를 나타냈다. 그러므로 이 방법은 우량균주개발을 위한 유용한 방법으로 판단되었다.

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양이온성 지질이 포함된 PEG 리포솜의 세포내 이입 및 항암효력 평가 (Intracellular delivery and anti-tumor activity of polyethyleneglycol liposomes containing cationic lipid)

  • 정순화;김성규;정석현;성하수;조선행;신병철
    • Journal of Pharmaceutical Investigation
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    • 제38권3호
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    • pp.163-169
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    • 2008
  • Liposomes are spherical vesicles composed of lipid bilayer membranes. However, the conventional liposomes have been found to be plagued by rapid opsonization and taken up by the reticuloendothelial system (RES), resulting in shortened circulation time and limited intracellular uptake to target cell. In this study, polyethyleneglycol-cationic liposomes (PCL) containing cationic lipid and DSPE-mPEG were prepared by thin film cast-hydration method. The PEG liposomes had approximately $97.0{\pm}1.3\;nm$ of mean particle diameter and $-21.7{\pm}1.2\;mV$ of zeta potential value. PCL had $96.4{\pm}1.8\;nm$ of mean particle diameter and $-8.7{\pm}1.1\;mV$ of zeta potential value with a decrease of about 10 mV compared to the PEG liposomes. Loading of model drug, doxorubicin (DOX), in liposomes were carried out by using remote loading method and the loading efficiency of DOX in liposomes was about $95.0{\pm}1.9%$. Intracellular uptake and cytotoxicity of PCL were higher than that of PEG liposomes to murine B16F10 melanoma cells. In addition, anti-tumor activity of PCL was similar to that of PEG liposomes on growth of A549 human lung carcinoma in BALB/c mice. Consequently, PCL modified with cationic lipid may be applicable as anticancer drug carriers that can increase intracellular uptake and therapeutic efficacy.

Synthesis, Characterization and Cosmetic Application of Self-Assembled Sericin-PEG Nanoparticle

  • E. S. Choung;S. Y. Eom;Kim, J. H.;Kim, K. S.;Kim, K. H.;Lee, K. G.;Lee, Y. W.;C. S. Cho
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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    • pp.501-519
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    • 2003
  • Silk Sericin(SS) is a natural protein extracted from cocoon of bombix mori and shows moisturizing effect to the skin due to a number of hydroxyl groups in the structure. But its application to cosmetics is limited due to its poor solubility in water. In order to solve this drawback and expand its application to cosmetics, polyethyleneglycol(PEG) was conjugated with sericin by reacting activated polyethyleneglycol(ActPEG). Reaction site of sericin is tyrosine residue, which was determined by using $^1$H-NMR. Random coil structure of sericin was transformed to beta-sheet structure by conjugating polyethyleneglycol. It was confirmed that melting point of sericin-PEG conjugate was lowered compared to that of each sericin and PEG due to the interaction between sericin and PEG in crystalline structure. Self-assembled sericin-PEG nanoparticle was obtained by dialyzing with alcohol solution of sericin-PEG conjugate against water. The particle is spherical and has 200-400nm of size. The moisturizing ability of sericin-PEG nanoparticle was much higher than that of sericin itself. Incorporation of vitamin A into sericin-PEG nanoparticle was carried out by diafiltration method. The content of incorporated Vitamin A in sericin-PEG nanoparticle was 8.9 wt%. Releasing behaviour of vitamin A incorporated into nanoparticle was tested in phosphate buffer, pH 7.4 at 37$^{\circ}C$. and half-life of Vitamin A release was 43hrs. Sericin-PEG nanoparticle exhibited higher moisturing effect than sericin itself and distilled water, respectively. No toxicity and irritation were observed in animal tests. It can be expected that the self-assembled sericin-PEG nanoparticle can be developed for cosmetics.

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