• 제목, 요약, 키워드: nitrile-substitution

검색결과 5건 처리시간 0.028초

니트릴작용기의 치환이 몇가지 이온성 액체의 물리적 특성에 미치는 영향 (Effects of Nitrile Group Substitution on the Physical Properties of Some Ionic Liquids)

  • 안범수
    • 한국응용과학기술학회지
    • /
    • v.31 no.2
    • /
    • pp.225-230
    • /
    • 2014
  • Several nitrile-functionalized ionic liquids have been prepared and characterized. An attempt was made to systematically characterize nitrile-functionalized ionic liquids on the basis of a few kinds of cations and anions. The detailed comparison of the differences in physicical characteristics such as UV-Vis spectroscopy, thermal stability, viscosity, solubility property, and electrochemical property before and after incorporation of a nitrile group were studied. The results showed that the incorporation of a nitrile group to cations could result in remarkable changes in these properties.

Effects of the Nitrile Group Substitution on the Gas Separation Properties of Aromatic Polyamide Membranes

  • Park, Ho-Seung;Jo, Won-Ho;Oh, Tae-Jin;Kang, Yong-Soo;Park, Hyun-Chae
    • Fibers and Polymers
    • /
    • v.1 no.2
    • /
    • pp.111-115
    • /
    • 2000
  • The effects of nitrile group substitution onto aromatic polyamide backbone on the gas permeability and permselectivity of the polymers are examined. The gas permeability of aromatic polyamides increase with increasing the content of nitrile group substitution, whereas the permselectivity decreases with increasing the nitrile group contents. The effects of chain linrearity on the permeability and permselectivity are also examined. The non-linearity of the polymers increases the permeability. These behaviors are interpreted in terms of chain packing and crystallinity of the aromatic polyamides.

  • PDF

니트릴기의 가수분해 반응을 이용한 흡수성 아크릴 혼방사의 물성 (Physical Properties of Absorbent Acryl Blended Yarns Prepared by Hydrolysis of Nitrile Groups)

  • 김홍성
    • 한국섬유공학회지
    • /
    • v.39 no.1
    • /
    • pp.56-61
    • /
    • 2002
  • Super-absorbent hydrogel fiber was prepared from polyacrylonitrile(PAN)-based acrylic fiber by hydrolyzing its nitrile groups. Chemical reaction of PAN and physical properties of hydrolyzed acryl/cotton blended yarn were analyzed using FT-IR spectrophotometer, wide angle X-ray diffractometer, differential scanning calorimetry, universal testing machine, and static honestmeter to discuss nitrile group substitution mechanism, microstructure of the hydrolyzed fiber, and other physical properties. Most nitrile groups of PAN were hydrolyzed to ionic groups such as carboxyl group err And the crystalline phase of the acrylic fiber was disrupted to amorphous phase after processing, but the fiber retained its original shape. Water-absorption ratio and antistatic resistance of the hydrolyzed acryl/cotton blended yarn increased greatly, but tensile strength decreased by half.

Bandgap engineering of nanosized carbon dots through electron-accepting functionalization

  • Choi, Jongwan;Kim, Nakjoong;Oh, Jin-Woo;Kim, Felix Sunjoo
    • Journal of Industrial and Engineering Chemistry
    • /
    • v.65
    • /
    • pp.104-111
    • /
    • 2018
  • We report tuning of energy bandgap of nanosized carbon dots by chemical modification with electron-accepting moieties. The carbon dot derivatives were synthesized by oxidation and hydrothermal reaction, followed by addition/substitution reactions, resulting in uniform-sized carbon dots. Structural characterization and photophysical investigation were performed by applying various microscopic and spectroscopic techniques. The bandgap of the carbon dots was controlled by chemical functionalization with nitro and nitrile groups, as evidenced by the red-shift in the absorption and photoluminescence emission spectra. Calculations based on density functional theory were employed to support the observed bandgap tuning via functionalization of the carbon dots.

Cyanoethyl화에 의한 제지용 섬유의 화학적 개질효과에 관한 연구 (A Study on Chemical Modification Effect of Papermaking Fiber by Cyanoethylation)

  • 윤세영;조병묵;오정수
    • 목재공학
    • /
    • v.25 no.1
    • /
    • pp.56-64
    • /
    • 1997
  • Since there are three hydroxyl groups on each anhydroglucose ring of the cellulose, the renewable resources, we can get various functional papers by the chemical modification of cellulose. The reaction involving the introduction of the ${\beta}$-cyanoethyl ($-CH_2-CH_2$-CN) group into organic substances containing reactive hydrogen atoms is known as cyanoethylation. Cellulose reacts with acrylonitrile in the presence of strong alkalis in a typical manner of primary and secondary alcohols to form cyanoethyl ethers. In cyanoethylation, important factors of reaction are temperature, concentration of the NaOH, and addition rate of acrylronitrile. FT-IR spectra of cyanoethyl group was confirmed at $2250cm^{-1}$, which corresponds the introduction of aliphatic nitrile group. Effect of cyanoethyl DS(degree of substitution) on strength properties was resulted that cyanoethylated BKP of DS 0.04 appeared to be the best choice for overall strength properties. Also, excellent thermal stability in aging characteristics was obtained.

  • PDF