• Title/Summary/Keyword: Dicyanovinyl

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Preparation and Thermal Properties of Poly(enaminonitriles-ester)s Derived from Dicyanovinyl-Containing Bis-Hydroxy Monomers

  • 김종태;공명선
    • Bulletin of the Korean Chemical Society
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    • v.18 no.3
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    • pp.328-333
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    • 1997
  • Dicyanovinyl-containing bis-hydroxy monomers, p-bis[1-(4-hydroxypiperidinyl)]-2,2-dicyanovinyl]benzene (2), p-bis[1-[1-(2-hydroxyethyl)piperazinyl]-2,2-dicyanovinyl]benzene (3), p-bis[1-(4-hydroxyphenylamino)-2,2-dicyanovinyl]benzene (4) and p-bis[1-[N-methyl-(N-hydroxyethyl)amino]]-2,2-dicyanovinyl]benzene (5) were prepared from p-bis(1-chloro-2,2-dicyanovinyl)benzene (1) and the corresponding amino alcohol. The poly(enaminonitriles-ester)s with a variety of chemical structures in the main chain were prepared from them. The chemical structure of polymers was confirmed through the syntheses of their corresponding model compounds. The polymers are easily soluble in polar aprotic solvents such as DMF, DMSO and NMP. Brittle and hard films can be cast from DMF solutions of polymers. Most polymers showed a large exotherm in DSC analyses and undergo a curing reaction around 350 ℃ to form insoluble materials. The polymers consisting of rigid aromatic moieties show 80-88% residual weight at 500 ℃ under nitrogen.

Synthesis, Spectral Property and Dyeing Assessment of Azo Disperse Dyes Containing Carbonyl and Dicyanovinyl Groups

  • Choi, Yun Seok;Lee, Kun Su;Kim, Hye Jin;Choi, Jong Yun;Kang, Soon Bang;Lee, Eui Jae;Keum, Gyochang
    • Bulletin of the Korean Chemical Society
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    • v.34 no.3
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    • pp.863-867
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    • 2013
  • A series of azo disperse dyes having dicyanovinyl groups was synthesized by the Knoevenagel condensation with malononitrile from carbonyl substituted phenylazo disperse dyes which were prepared by conventional diazo coupling reaction of aniline derivatives as diazo components. A variety of coupling components such as anilines, an indole and a pyridone were used. The azo disperse dyes were evaluated for their spectral properties and dyeing assessment on the polyester fabrics. The azo disperse dyes containing dicyanovinyl groups showed bathochromic shifts and darker colors due to increased electron withdrawing strength in their azo components and extended conjugation by dicyanovinyl groups than their parent carbonyl substituted azo dyes. The dyes containing 2-acetylamino-5-methoxy substituent in the coupling component exhibited higher wavelength of maximum absorbance (${\lambda}_{max}$) and significant negative solvatochromism than those of other dyes due to intramolecular hydrogen bonding.

Hydroxy-Substituted Polyenaminonitrile as a Soluble Precursor for Rigid-Rod Polybenzoxazole

  • Kim, Ji Heung;Lee, Jae Gwan
    • Bulletin of the Korean Chemical Society
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    • v.22 no.9
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    • pp.999-1004
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    • 2001
  • (1-Chloro-2,2-dicyanovinyl)benzene or 1,4-bis(1-chloro-2,2-dicyanovinyl)benzene was reacted with 2-amino-phenol to give the model compound, hydroxy enaminonitrile, which was found to undergo thermal cyclization reaction to form the corresponding benzoxazole. This intramolecular cyclization reaction is expected to occur through nucleophilic attack to electropositive enamine carbon by ortho-hydroxy group on the phenyl ring, which is accompanied by the release of neutral malononitrile through rearrangement. From each bifunctional monomer, o-hydroxy substituted polyenaminonitrile was prepared and characterized as a new precursor polymer for well-known aromatic polybenzoxazole. Also the unusual macrocyclic dimer formation from the 1,4-bis(1-chloro-2,2-dicyanovinyl)benzene and 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane polymerization reaction system was discussed. The thermal cyclization reactions and the properties of polymers were investigated using FT-IR and thermal analysis (DSC & TGA).

Preparation of Polyenaryloxynitriles from Dicyanovinyl Chloride and Diphenol Derivatives in the Presence of DABCO

  • Geum, Ne Ri;Gong, Myeong Seon
    • Bulletin of the Korean Chemical Society
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    • v.21 no.11
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    • pp.1111-1114
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    • 2000
  • The kinetic study of the enaryloxynitriles via the nucleophilic vinylic substitution reaction of various phenol derivatives with 1-chloro-1-phenyl-2,2-dicyanoethene (1) was conducted in the presence of 1,4-diazabicyclo[2,2,2]octane (DABCO). Nucleo philic vinylic substitution of phenol derivatives with electrophilic olefins carrying sluggish leaving group involves a third-order reaction. The reaction was applied to solution polymerization of diphenol derivatives with p-bis(1-chrolo-2,2-dicyanovinyl)benzene (2), which yielded various polyenaryloxynitriles with moderate molecular weight.

Synthesis of Poly(enaryloxynitriles) Containing Schiff Bases and Their Thermal Properties

  • 김상곤;한양규;공명선
    • Bulletin of the Korean Chemical Society
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    • v.16 no.4
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    • pp.326-331
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    • 1995
  • Poly(enaryloxynitriles) containing Schiff bases were prepared from p-bis(1-chloro-2,2-dicyanovinyl)benzene (2) and various aromatic diols having Schiff base moiety by interfacial polymerization. The chemical structure of the polymers was confirmed through synthesis of their corresponding model compounds. All the polymers were soluble in polar aprotic solvents and their brittle films were cast from DMF solution. They showed a large exotherm around 340 ℃ attributable to the chemical change of dicyanovinyl group. Especially, curing of azomethine group was observed to occur at 390 ℃ by differential scanning calorimetry. According to the thermogravimetric analyses, they exhibited excellent thermal stability with 60-90% residual weight at 500 ℃ in nitrogen.

Preparation of New Polyenaminonitriles Containing Cyclic and Methylene Units and Their Thermal Properties

  • Cho, Jeong-Hyun;Gong, Myoung-Seon
    • Macromolecular Research
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    • v.8 no.5
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    • pp.209-214
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    • 2000
  • Polyenaminonitriles containing cycloaliphatic and aliphatic units were prepared by interfacial or solution polymerization reaction of p-bis(1-chloro-2,2-dicyanovinyl) benzene (1) with 4-aminobenzyl-amine, 1-(2-aminoethyl)piperazine, 2-(aminomethyl)pyrrolidine and 4-(aminomethyl)piperidine. The chemical structure of the polymers was confirmed through a syntheses of the model compound. The resulting polymers possessed inherent viscosities of 0.29∼0.62 dL/g and they were easily soluble in polar aprotic solvents and common organic solvents. Thermal properties of the polymers such as curability and stability were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and infrared spectroscopy. The polymers exhibited a large exotherm in DSC analyses and underwent a curing reaction around 340-370$\^{C}$ to form insoluble materials. The polymers showed 70-80% residual weight at 600 $\^{C}$ under nitrogen.

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Teaching a Known Molecule New Tricks: Optical Cyanide Recognition by 2-[(9-Ethyl-9H-carbazol-3-yl)methylene]propanedinitrile in Aqueous Solution

  • Tang, Lijun;Zhao, Guoyou;Wang, Nannan
    • Bulletin of the Korean Chemical Society
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    • v.33 no.11
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    • pp.3696-3700
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    • 2012
  • The colorimetric and fluorescent cyanide recognition properties of 2-[(9-ethyl-9H-carbazol-3-yl)methylene]-propanedinitrile (1) in $CH_3CN-H_2O$ (2/1, v/v, HEPES 10 mM, pH = 7.0) solution were evaluated. The optical recognition process of probe 1 exhibited high sensitivity and selectivity to cyanide ion with the detection limit of $2.04{\times}10^{-6}$ M and barely interfered by other coexisting anions. The sensing mechanism of probe 1 is speculated to undergo a nucleophilic addition of cyanide to dicyanovinyl group present in compound 1. The colorimetric and fluorescent dual-modal response to cyanide makes probe 1 has a potential utility in cyanide detection.

Preparation of Polyesters Containing Enaryloxynitrile Moiety and Their Thermal Properties

  • Moon Sung-Hee;Lee Seung-Jae;Kim Jin-Bong;Gong Myoung-Seon
    • Bulletin of the Korean Chemical Society
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    • v.15 no.12
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    • pp.1089-1093
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    • 1994
  • Polyesters containing enaryloxynitriles moiety have been newly prepared from p-bis[1-[4-(3-hydroxypropyl)phenoxy]-2,2-dicyano vinyl]benzene (3) and common diols with terephthaloyl chloride. The copolyesters have a good solubility in common organic solvents as well as polar aprotic solvents. They undergo a curing reaction at around 350 $^{circ}C$ and show a 50-60${\%}$ of residual weight at 500 $^{circ}C$. The enhanced thermal stabilities were due to the intramolecular cyclization or intermolecular cross-linking reaction of the dicyanovinyl group incorporated into polyester by copolymerization.