Synthesis and properties of novel Y‐type nonlinear optical polyimides with high thermal stability of second harmonic generation

Abstract

2,4-Bis-(3,4-dicarboxyphenylcarboxyethoxy)-1-(2,2-dicyanovinyl)benzene dianhydride (4) was prepared and reacted with 4,4 0 -oxydianiline, 4,4 0 -diaminobenzanilide and 4,4 0 -(hexafluoroisopropylidene)dianiline to yield novel Y-type polyimides 5-7 containing 2,4-dioxybenzylidenemalononitrile groups as nonlinear optical (NLO) chromophores, which constitute parts of the polymer backbone. The resulting polyimides 5-7 are soluble in polar solvents such as dimethylsulfoxide and N,N-dimethylformamide. Polymers 5-7 showed a thermal stability up to 330 8C in thermogravimetric analysis thermograms with T g values obtained from differential scanning calorimetry thermograms in the range 179-194 8C. The second harmonic generation (SHG) coefficients (d 33 ) of poled polymer films at the 1064 nm fundamental wavelength were around 5.56 3 10 À9 esu. The dipole alignment exhibited exceptionally high thermal stability even at 20 8C higher than the glass-transition temperature there was no SHG decay below 215 8C because of the partial main-chain character of polymer structure, which is acceptable for NLO device applications. V V C 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: [3078][3079][3080][3081][3082][3083][3084][3085][3086][3087] 2008

Facile synthesis and electro‐optic activities of new polycarbonates containing tricyanofuran‐based nonlinear optical chromophores

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Synthesis and characterization of new poly(ester-imide)s based on 1,3-bis[4,4′-bis(trimellitimido) phenyl]-2-propenone and aromatic diols

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