Synthesis and nonlinear optical properties of novel Y-type polyester containing tricyanovinylthiazolylazoresorcinoxy group with enhanced thermal stability of dipole alignment

Abstract

Novel Y-type polyester 4 containing 5-methyl-4-{5-(1,2,2-tricyanovinyl)-2-thiazolylazo}resorcinoxy groups as nonlinear optical (NLO) chromophores, which are parts of the polymer backbone, was prepared, and its NLO properties were investigated. Polyester 4 is soluble in common organic solvents such as N,N-dimethylformamide and dimethylsulfoxide. Polymer 4 shows a thermal stability up to 250 °C from thermogravimetric analysis with glass-transition temperature obtained from differential scanning calorimetry of approximately 94 °C. The second harmonic generation (SHG) coefficient (d33) of poled polymer film at 1560-nm fundamental wavelength is 8.12 × 10−9 esu. The dipole alignment exhibits a thermal stability even at 6 °C higher than glass-transition temperature (Tg), and no significant SHG decay is observed below 100 °C due to the partial main-chain character of polymer structure, which is acceptable for NLO device applications. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011