Molecular design, synthesis, and properties of Y‐type nonlinear optical polyester containing tricyanovinylthiophene with enhanced thermal stability of second harmonic generation

Abstract

1‐{3,4‐Di‐(2‐hydroxyethoxy)phenyl}‐2‐(2‐thiophenyl)ethene (5) was prepared and condensed with terephthaloyl chloride to yield polyester (6). Polymer 6 was reacted with tetracyanoethylene to give a new Y‐type polyester (7) containing 1‐(3,4‐dioxyethoxy)phenyl‐2‐{5‐(2,2,3‐tricyanovinyl)‐2‐thiophenyl)}ethenyl groups as NLO‐chromophores, which are components of the polymer backbones. Polyester 7 is soluble in common organic solvents such as N,N‐dimethylformamide and acetone. Polymer 7 showed a thermal stability up to 300 °C in thermogravimetric analysis with glass transition temperature (Tg) obtained from differential scanning calorimetry near 126 °C. The second harmonic generation (SHG) coefficient (d33) of poled polymer film at the 1560 nm fundamental wavelength was around 6.57 × 10−9 esu. The dipole alignment exhibited high thermal stability up to the Tg, and there was no SHG decay below 125 °C due to the partial main‐chain character of polymer structure, which is acceptable for NLO device applications. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1911–1919, 2009

Synthesis and Nonlinear Optical Properties of Novel T-type Polyester Containing Thiophene with Enhanced Thermal Stability

“…The resulting polymer 7 shows a thermal stability up to 300 o C from TGA thermograms with T g value near 113 o C. The SHG coefficient (d33) of corona-poled polymer film was 1.85 pm/V. The structural feature of this polymer is that it exhibits a greater thermal stability even at 10 o C higher than T g and no significant SHG decay is observed below 125 o C. This SHG thermal stability is similar with those of Y-type polyesters containing the same NLO chromophores, which are in the range 125 -135 o C. 15,18 This high thermal stability of optical nonlinearity stems from the stabilization of dipole alignment of the NLO chromophores, which constitute a part of the polymer backbone. We are now in the process of extending the polymerization system to the synthesis of other type of NLO polymers and the results will be reported elsewhere.…”

Synthesis and electro-optic properties of novel X-type polyester containing dioxynitrobenzylidenecyanoacetate with highly enhanced thermal stability of dipole alignment

“…Side-chain NLO polymer systems have the advantages such as good solubility, homogeneity and high loading level of NLO chromophores, but they often suffer from poor stability of dipole alignments at high temperatures. Recently, we prepared novel Y-type polyesters containing dioxynitrostilbene [37,38], dioxybenzylidenemalononitrile [39][40][41], dioxybenzylidenecyanoacetate [42,43], tricyanovinylthienylcatechol [44], tricyanovinylthienylresorcinol [45], tricyanovinylthiazolylazoresorcinol [46], and dioxynitroazobenzene [47,48] as NLO chromophores. The resulting polymers exhibit enhanced thermal stability of second harmonic generation (SHG), which stems from the stabilization of dipole alignment of the NLO chromophores.…”

Synthesis and properties of novel X-type nonlinear optical polyester containing nitrophenylazonitroresorcinoxy group with highly enhanced SHG thermal stability

“…Side-chain NLO polymers have the advantages such as good solubility, homogeneity and high loading level of NLO chromophores, but they often suffer from poor stability of dipole alignments at high temperatures. Recently we prepared novel NLO polyesters containing dioxynitrostilbene [25,26], dioxybenzylidenemalononitrile [27e29], dioxybenzylidenecyanoacetate [30,31], tricyanovinylthienylcatechol [32], tricyanovinylthienylresorcinol [33], tricyanovinylthiazolylazoresorcinol [34], and dioxynitroazobenzene [35,36] as NLO chromophores. The resulting polymers exhibit enhanced thermal stability of second harmonic generation (SHG), which stems from the stabilization of dipole alignment of the NLO chromophores.…”