• Title/Summary/Keyword: diglycidyl aniline

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Synthesis of Aniline-Based Azopolymers for Surface Relief Grating

  • Jung, Woo-Hyuk;Ha, Eun-Ju;Chung, Il-Doo;Lee, Jang-Oo
    • Macromolecular Research
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    • v.16 no.6
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    • pp.532-538
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    • 2008
  • Epoxy-based azopolymers were synthesized by the reaction of the diglycidyl ether of bisphenol A (DGEBA) or N,N-diglycidyl aniline (DGA) with disperse orange 3 (DO3) to give poly(DGEBA-co-DO3) or poly(DGA-co-DO3), respectively. Aniline-based azopolymers prepared from poly(DGA-co-An) precursors, synthesized by the reaction of DGA with aniline, were produced by the post-azo coupling reaction with diazonium salts containing various substituents. Holographic gratings were carried out to measure the diffractive efficiencies (DE) for the interference patterns of the $Ar^+$ laser from 50 to $300\;mW/cm^2$ intensity. The shorter repeating unit with higher chromophore density induced deeper surface relief gratings (SRG). Large surface gratings were observed for the aniline-based azopolymers with -COOH substituents, as compared with those for epoxy-based azopolymers. The aniline-based azopolymers with dimerized chromophores and various substituents were also synthesized to observe the effect of chromophore substituents and dimerization on the holography. The dimerized chromophores were more sensitively photoisomerized by the $Ar^+$ laser beam, and demonstrated a larger grating than that with one azo bond.

Time-Temperature-Transition Diagrams with Liquid Crystalline Phase Changes of Liquid Crystalline Epoxy (열경화성 액정 에폭시 수지의 액정상 변화를 포함한 시간-온도-전이 다이어그램)

  • Seung Hyun Cho
    • Composites Research
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    • v.37 no.3
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    • pp.215-218
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    • 2024
  • Liquid crystalline thermosetting epoxy oligomer DD-A was synthesized with Diglycidyl ether of 4,4'-dihydroxy-α-methylstilbene (DGE-DHMS) and aniline in a ratio of 2:1 and cured with a catalytic curing agent, 1-Methyl Imidazole. The gelation times and vitrification times were measured to create Time-Temperature-Transition Diagrams with liquid crystalline phase changes. It was found that the gelation and vitrification times were decreased as the concentration of curing agent increased, and the vitrification curve showing a typical S-shape was confirmed.