• Title/Summary/Keyword: ESU

Search Result 31, Processing Time 0.014 seconds

Synthesis and Properties of Novel Y-type Nonlinear Optical Polyester Containing Cyanovinylthiophene with Enhanced Thermal Stability of Second Harmonic Generation

  • Lee, Ga-Young;Kim, Jin-Hyang;Jang, Han-Na;Won, Dong-Seon;No, Hyo-Jin;Lee, Ju-Yeon;Rhee, Bum-Ku;Choi, Hee-Dok
    • Bulletin of the Korean Chemical Society
    • /
    • v.30 no.3
    • /
    • pp.661-666
    • /
    • 2009
  • 1-{2,4-Di-(2-hydroxyethoxy)phenyl}-2-(2-thienyl)ethene (5) was prepared and condensed with terephthaloyl chloride to yield polyester (6). Polymer 6 was reacted with tetracyanoethylene to give novel Y-type polyester (7) containing 1-(2,4-dioxyethoxy)phenyl-2-{5-(2,2,3-tricyanovinyl)-2-thienyl)}ethenyl groups as NLO-chromophores, which are parts the polymer backbones. Polymer 7 is soluble in common organic solvents such as acetone and N,N-dimethylformamide. It showed thermal stability up to 300 ${^{\circ}C}$ in thermogravimetric analysis with glasstransition temperature obtained from differential scanning calorimetry near 134 ${^{\circ}C}$. The second harmonic generation (SHG) coefficient ($d_33$) of poled polymer film at the 1560 nm fundamental wavelength was around 6.74 x $10^{-9}$ esu. The dipole alignment exhibited high thermal stability up to the glass-transition temperature ($Tg$), and there was no SHG decay below 135 ${^{\circ}C}$ because of the partial main-chain character of polymer structure, which is acceptable for NLO device applications.