Abstract
A novel Y-type polyester 4 containing 5-methyl-4-{5-(1,2,2-tricyanovinyl)-2-thiazolylazo}resorcinoxy groups as nonlinear optical (NLO) chromophores was prepared and characterized. Polyester 4 is soluble in common organic solvents such as acetone and N,N-dimethylformamide. It shows a thermal stability up to 250°C from thermogravimetric analysis thermogram with a glass-transition temperature (T g ) obtained from differential scanning calorimetry thermogram of around 94°C. The second harmonic generation (SHG) coefficient (d 33 ) of poled polymer film at 1064 nm fundamental wavelength is 8.12 × 10−9 esu. The dipole alignment exhibits a thermal stability even at 6°C higher than T g and there is no significant SHG decay below 100°C due to the partial main-chain character of the polymer structure, which is acceptable for nonlinear optical device applications.
Acknowledgment
This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (No. 2010–0020951).
Notes
a Polymer film after poling.
b SHG coefficients (d 33) were derived from the analysis of measured Maker-fringes [Citation11].
c Film thickness was determined by the optical transmission technique [Citation10].