• 제목/요약/키워드: Amine groups

검색결과 231건 처리시간 0.025초

固體酸의 非水溶液에서의 吸着메카니즘에 관한 硏究 (Adsorption Mechanism of Solid Acid in Nonaqueous Solution)

  • 권오천
    • 대한화학회지
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    • 제9권4호
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    • pp.185-189
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    • 1965
  • 韓國産 酸性白土類 및 silica gel을 aniline yellow, o-nitro aniline, oil orange 色素 benzene 溶液과 작용시켜 非水溶液에서의 色素吸着率을 측정하였다. 그 吸着率은 silica gel이 酸性白土類보다 컸으며 酸性度에는 무관하였다. 또 上記 色素溶液에 각 10%의 添加溶劑 amine, alcohol, halogen類 化合物등을 加하여 高體酸의 色素吸着率의 변화(吸着阻害率)에 대하여 조사한 결과 위에 적은 順으로 그 영향이 적어지고, 同族體에서는 分子量이 적을 수록 그 영향이 커짐을 알았다. 따라서 非水溶液에서의 吸着은 amine基, 水酸基등과 같은 陰性基를 갖는 化合物은 選擇吸着하고 界面張力에 무관계하여 Traulbe系列의 逆轉現象을 나타내었다. 그 逆轉現象(吸着潮害現象)은 그 順位가 添加溶制의 雙極子能率과 대체적으로 일치하는 것으로 보아 固體酸模體인 活性硅酸과 被吸着體사이의 極盛的化學吸着에 의한 것이라 推定된다. 本實驗結果로부터 固體酸의 非水溶液에서의 吸着메카니즘, Traube 系列의 逆轉現象에 관하여 考察하게 되었다.

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High performance epoxy nanocomposites with amine-functionalized graphenes

  • 박솔몬;김대수
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2010년도 추계학술발표논문집 1부
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    • pp.470-473
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    • 2010
  • Graphene, consisting of a single layer of carbon in a two-dimensional lattice, has been emerging as a fascinating material with many unique physical, chemical and mechanical properties. In this study, graphenes were prepared by a chemical method. To develop high performance polymer nanocomposites reinforced by graphenes, adequate dispersion of the fillers and strong interfacial bonding between the fillers and the polymer matrix are essential. The purpose of this study was to examine the influence of introducing amine groups on the surfaces of graphenes. FT-IR spectroscopy, SEM were used to confirm the functionalization. Epoxy nanocomposites comprising the graphenes were prepared and their characteristics were investigated by DSC, DMA and TMA. Fracture surfaces of the nanocomposites were investigated by SEM. The functionalized graphenes induced strong interfacial bonding than the pristine graphenes and resulted in considerable improvements in the performance of the nanocomposites.

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니트릴에 의해 개질된 가교구조 수지의 특성 (Characteristics of Crosslinked Resin Modified with Nitriles)

  • 심미자
    • 한국재료학회지
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    • 제9권4호
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    • pp.373-377
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    • 1999
  • The cure mechanicsm and cure kinetics of diglycidyl ether of bisphenol A(DGEBA)/4,4'-methylene dianiline(MDA)/nitrile(MN, SN, GN) systems were studied by FT-IR and DSC to develop new applications in the biomedical polymer fields. The network structure of the DGEBA/MDA system was changed to the chain-extended network structure by the addition of nitriles. The reactions contributed to the chain extension were the primary amine-nitrile and hydroxyl-nitrile reactions. The chain-extended network structure could be indirectly proved by the decrement of T\ulcorner and the increment of impact strength with the increasing nitrile content. The cure rate of DGEBA/MDA/nitrile system was lower than that of DGEBA/MDA system due to the disturbance of nitrile group in the reaction of primary amine and epoxide groups.

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2차 아미노기를 갖는 실리카 나노입자와 (메타)아크릴레이트 단량체와의 마이클 부가반응에 대한 분광학적 분석 (Spectroscopic Analysis on the Michael Addition Reaction between Secondary Amino Group Containing Silica Nanoparticles with (Meth)acrylate Monomers)

  • 전하나;하기룡
    • 폴리머
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    • 제36권5호
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    • pp.668-676
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    • 2012
  • 본 연구에서는 실리카 나노입자를 bis[3-(trimethoxysilyl)propyl]amine(BTMA) 실란 커플링제로 표면 개질한 후, 실리카에 도입되는 2차 아미노기인 -NH기와 Michael 부가반응이 가능한 acrylate기를 가지는 trimethylolpropane ethoxylate triacrylate(TMPET)와 3-(acryloyloxy)-2-hydroxypropyl methacrylate(AHM)로 표면 처리를 하여 반응성(meth)acrylate기를 가지는 brush를 도입하는 연구를 수행하였다. 1분자에 Michael 부가반응성이 있는 acrylate기를 3개 갖는 TMPET와 1분자에 반응성이 있는 acrylate기와 반응성이 없는 methacrylate기를 각각 1개씩 갖는 AHM을 사용하여, 처리 몰(mol)수의 변화가 실리카 표면에 도입되는 (meth)acrylate기에 미치는 영향을 Fourier transform infrared spectroscopy(FTIR), elemental analysis(EA) 및 고체 상태 cross-polarization magic angle spinning(CP/MAS) nuclear magnetic resonance spectroscopy(NMR)법을 사용하여 분석하였다. BTMA로 개질된 실리카를 TMPET로 처리하면, 액체상태의 순수 TMPET와 순수 BTMA의 반응과는 달리 TMPET 1분자당 3개씩 결합있는 acrylate기 대부분이 BTMA의 -NH기와 Michael 부가반응이 일어나는 것을 확인하였다. 따라서 BTMA로 처리한 실리카에 Michael 부가반응으로 반응성 (meth)acrylate기를 도입하기 위하여서는 AHM과 같이 Michael 부가반응성이 있는 acrylate기와 Michael 부가반응성이 없는 methacrylate기를 각각 1개씩 가지는 AHM을 사용하는 것이 필요함을 확인하였다.

Resistive Switching Memory Devices Based on Layer-by-Layer Assembled-Superparamagnetic Nanocomposite Multilayers via Nucleophilic Substitution Reaction in Nonpolar Solvent

  • 김영훈;고용민;구본기;조진한
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2011년도 춘계학술발표대회
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    • pp.243.1-243.1
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    • 2011
  • We demonstrate a facile and robust layer-by-layer (LbL) assembly method for the fabrication of nonvolatile resistive switching memory (NRSM) devices based on superparamagnetic nanocomposite multilayers, which allows the highly enhanced magnetic and resistive switching memory properties as well as the dense and homogeneous adsorption of nanoparticles, via nucleophilic substitution reaction (NSR) in nonpolar solvent. Superparamagnetic iron oxide nanoparticles (MP) of about size 12 nm (or 7 nm) synthesized with oleic acid (OA) in nonpolar solvent could be converted into 2-bromo-2-methylpropionic acid (BMPA)-stabilized iron oxide nanoparticles (BMPA-MP) by stabilizer exchange without change of solvent polarity. In addition, bromo groups of BMPA-MP could be connected with highly branched amine groups of poly (amidoamine) dendrimer (PAMA) in ethanol by NSR of between bromo and amine groups. Based on these results, nanocomposite multilayers using LbL assembly could be fabricated in nonpolar solvent by NSR of between BMPA-MP and PAMA without any additional phase transfer of MP for conventional LbL assembly. These resulting superparamagnetic multilayers displayed highly improved magnetic and resistive switching memory properties in comparison with those of multilayers based on water-dispersible MP. Furthermore, NRSM devices, which were fabricated by LbL assembly method under atmospheric conditions, exhibited the outstanding performances such as long-term stability, fast switching speed and high ON/OFF ratio comparable to that of conventional inorganic NRSM devices produced by vacuum deposition.

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Poly(Styrene-co-GMA)의 합성과 in situ Reactive Compatabilizer 로서의 응용 (Synthesis of Poly(Styrene-co-GMA) and its Application as in situ Reactive Compatabilizer)

  • 김주영;서경도
    • 공업화학
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    • 제3권3호
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    • pp.499-506
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    • 1992
  • 모노머의 반응성비가 각각 $r_1=0.53$, $r_2=0.44$반응인 styrene과 GMA(glycidyl methacrylate)를 일정 몰비로 반응시켜서 styrene과 GMA의 공중합체인 PGS를 합성한 후, 에틸렌 디아민을 반응시켜서 공중합체내에 아민기를 도입시켰다. 아민기가 도입된 중합체인 NPGS는 PGMA와 블렌드시에 DSC분석 결과, 단일 Tg를 나타내므로 두 폴리머는 상용 성이 있다는 것이 관찰되었다. 이 NPGS-PGMA의 블렌드를 PS-PGMA블렌드물에 일정무게비로 첨가하여서 이에 따른 상용성의 변화를 관찰하였다. 즉, 비상용성인 PS-PGMA블렌드에, 에폭시기와 아민기와의 화학적 반응에 의하여 상용성을 나타내는 NPGS-PGMA블렌드의 첨가에 따른 상용성의 향상을 DSC분석을 통한 Tg변화와 SEM (Scanning electron microscopy)측정에 의한 morphology변화를 통하여서 관찰하였다. 측정 결과, PS-PGMA 블렌드는 NPGS-PGMA 블렌드가 첨가됨에 따라 Tg변화를 나타내었고, PGMA의 PS내에서의 분산은 향상되었다. 따라서, NPGS-PGMA의 블렌드는 PS-PGMA블렌드의 상용성을 향상시키는 상용화제로서의 작용을 하였다.

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Repairing Damaged Hair Using Pentapeptides of Various Amino Acid Sequences with Crosslinking Reaction

  • Choi, Wonkyung;Son, Seongkil;Song, Sang-Hun;Kang, Nae Gyu;Park, Sun-gyoo
    • Korea Journal of Cosmetic Science
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    • 제2권1호
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    • pp.11-19
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    • 2020
  • The aim of this study is to investigate the effect of various pentapeptides on hair repair depending on the characteristics of comprising amino acids using crosslinking agents in hair. Total ten peptides were synthesized with two kinds of amino acids respectively, of which were previously categorized according to R group of the amino acids contributing to the characteristic of each peptide: STTSS (Ser-Thr-Thr-Ser-Ser), LIILL (Leu-Ile-Ile-Leu-Leu), CMMCC (Cys-Met-Met-Cys-Cys), DEEDD (Asp-Glu-Glu-Asp-Asp), RKKRR (Arg-Lys-Lys-Arg-Arg), TAMRA-STTSS, TAMRA-LIILL, TAMRA-CMMCC, TAMRA-DEEDD, and TAMRA-RKKRR. Pentapeptide alone, or pentapeptides with crosslinking agents such as polymeric carbodiimide (PCI) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) were treated to chemically damaged hair. Hair diameter and break strength (N = 40/case) were measured to calculate tensile strength of hair for computing hair repair ratio, and fluorescence yields (N = 20/case) were collected for hair treated with TAMRA-peptides. The tensile strength of hair treated with pentapeptides alone, or pentapeptides with cross-linking agents is consistent with the fluorescence yield from the microscope images of the cross-sectioned hair in vision and in numerical values. Pentapeptides consisting of hydrophobic amino acids (LIILL), amino acids with sulfur (CMMCC), and basic amino acids (RKKRR) increased the tensile strength in perm-damaged hair. Pentapeptides with no extra carboxyl/amine groups in R group of amino acids resulted in no significant differences in hair strength and fluorescence yield among hairs treated with alone and with crosslinkers. Pentapeptides with extra carboxyl groups or amine groups enabled further strengthening of hair due to increased bonds within the hair after carbodiimide coupling reaction. The hair repairs of pentapeptides with various amino acid sequences were studied using crosslinking. Depending on the physical characteristics of comprising amino acids, the restoration of damaged hair was observed with tensile strength of hair and fluorescence signals upon cross-sectioned hair in parallel to possibly understand the binding tendency of each pentapeptide within the hair.

감염성 질염에 대한 질내 산도측정, Amine 검사 및 현미경 검사의 진단적 가치 (Diagnostic Values of pH of Vaginal Discharge, Amine Test, and Microscopic Examination of Infectious Vaginitis)

  • 최재동;김기득;고민환;이태형;정원형
    • Journal of Yeungnam Medical Science
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    • 제5권2호
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    • pp.129-139
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    • 1988
  • 1987년 5월 1일부터 9월 31일까지 5개월간 영남대학교 의과대학 부속병원 산부인과외래에 내원한 환자 549예를 대상으로 질내 pH 검사, 아민검사, 생리식염수 및 10% KOH습식도말현미경검사를 시행하였다. 질염과 관련된 임상증상 및 소견과 이를 기초로 한 이학적 진단과 비교분석한 결과 다음과 같은 성적을 얻었다. 1. 각 감염성 질염에서의 질산도 측정 및 아민검사와 생리식염수 습식도말검사성적은 세균성 질염 환자군에선 질 pH 5.0 이상이 81.0%, 아만검사 양성이 62.8%, 유산균 감소 소견이 77.4%, 백혈구 감소가 70.1%이었으며, 트리코모나스 질염 환자군은 질 pH 5.0 이상이 93.3%, 아민검사 음성이 90.0%, 유산균 감소가 90.0%, 백혈구 증가가 93.3%이었다. 진균성 질염 환자군은 질 pH 3.0 또는 4.0이 83.2%, 아민검사 음성이 100%, 정상유산균 소견이 89.7% 및 정상백혈구 소견이 72.4%이었다. 2. 생리식염수 및 10% KOH 습식도말검사에 대한 이학적 진단의 정확도는 정상군이 77.6%. 세균성 질염군 26.3%, 진균성 질염군 47.5% 및 트리코모나스 질염군이 70.0%이었다. 질 pH 측정 및 아민검사에 의한 진단의 정확도는 정상 및 진균성 질염군이 83.2%, 세균성 질염군이 60.6%, 트리코모나스 질염군이 83.3%이었다. 3. 세균성 질염군에서 질 pH 3.0 또는 4.0 및 아민검사 음성을 나타낸 23예의 질상피 세포에 대한 clue cell의 비율은 10.0%이하가 12예, 20.0% 및 30.0%가 5예, 50.0%가 4예, 그리고 50.0% 이상이 2예이었다. 이상의 성적으로 외래에서 손쉽게 시행할 수 있는 질내 산도측정과 아민검사는 각 감염성 질염의 감염여부에 대한 screening과 감별진단에 유용한 것으로 사료되며, 생리식염수 및 10% KOH 습식도말검사에 이들 검사를 추가할 경우 진단의 신빙도를 높일 수 있을 뿐만 아니라 배양검사가 요구되는 환자의 선택에 있어서도 가치가 있을 것으로 추정되었다.

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Effect of CQ-amine ratio on the degree of conversion in resin monomers with binary and ternary photoinitiation systems

  • Moon, Ho-Jin;Shin, Dong-Hoon
    • Restorative Dentistry and Endodontics
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    • 제37권2호
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    • pp.96-103
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    • 2012
  • Objectives: This study evaluated the effect of camphorquinone (CQ)-amine ratio on the C=C double bond conversion of resins with binary and ternary photoinitiation systems. Materials and Methods: Two monomer mixtures (37.5 Bis-GMA/37.5 Bis- EMA/25 TEGDMA) with binary systems (CQ/DMAEMA in weight ratio, group A [0.5/1.0] and B [1.0/0.5]) and four mixtures with ternary system (CQ/OPPI/DMAEMA, group C [0.1/1.0/0.1], D [0.1/1.0/ 0.2], E [0.2/1.0/0.1] and F [0.2/1.0/0.2]) were tested: 1 : 2 or 2 : 1 CQ-amine ratio in binary system, while 1 : 1 ratio was added in ternary system. The monomer mixture was cured for 5, 20, 40, and 300 sec with a Demetron 400 curing unit (Demetron). After each exposure time, degree of conversion (DC) was estimated using Fourier transform infrared (FTIR) spectrophotometer (Nicolet 520, Nicolet Instrument Corp.). The results were analyzed by ANOVA followed by Scheffe test, with p = 0.05 as the level of significance. Results: DC (%) was expressed in the order of curing time (5, 20, 40, and 300 sec). Group A ($14.63{\pm}10.42$, $25.23{\pm}6.32$, $51.62{\pm}2.69$, $68.52{\pm}2.77$); Group B ($4.04{\pm}6.23$, $16.56{\pm}3.38$, $37.95{\pm}2.79$, $64.48{\pm}1.21$); Group C ($16.87{\pm}5.72$, $55.47{\pm}2.75$, $60.83{\pm}2.07$, $68.32{\pm}3.31$); Group D ($23.77{\pm}1.64$, $61.05{\pm}1.82$, $65.13{\pm}2.09$, $71.87{\pm}1.17$); Group E ($28.66{\pm}2.92$, $56.68{\pm}1.33$, $60.66{\pm}1.17$, $68.78{\pm}1.30$); Group F ($39.74{\pm}6.31$, $61.07{\pm}2.58$, $64.22{\pm}2.29$, $69.94{\pm}2.15$). Conclusion: All the monomers with ternary photoinitiation system showed higher DC than the ones with binary system, until 40 sec. Concerning about the effect of CQ-amine ratio on the DC, group A converted into polymer more than group B in binary system. However, there was no significant difference among groups with ternary system, except group C when cured for 5 sec only.

도공층 구조 및 도공지의 인쇄적성에 관한 연구(II) - 라텍스 이온기가 도공층 구조에 미치는 영향 - (Studies on the Coating Structure and Printability of Coated Paper(II) - Effect of Ionic Groups of Latices on Coating Structure -)

  • 이용규;박규재
    • Journal of the Korean Wood Science and Technology
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    • 제25권4호
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    • pp.10-16
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    • 1997
  • This study was carried out to improve coating structure by controlling the electrostatic interaction of coating components and by changing the coating structure of coated paper prepared with amphoteric and anionic latices. The results indicated that amphoteric latex copolymerized with carboxylic and amine groups had stronger interaction with other coating components than anionic latex with branched carboxylic group by controlling pH. These properties of amphoteric latex showed positive effects on viscosity rheology, and supernatant sediment of coating color. The coated paper using amphoteric latex had also produced more porous and smoother coverage of the coating layer than that using anionic latex. This porous and smooth coating layer showed better optical properties and printability than those of anionic latex such as opacity, porosity, ink set-off, and wet ink receptivity.

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