| 초록 |
Side-chain NLO polymers have good solubility, but they suffer from lower thermal stability of dipole alignment. Main-chan NLO polymers have good thermal stability of dipole alignments, but they often do not dissolve in organic solvents. In this work, we prepared a novel polyurethane containing 7 containing 1-(2,5-dihydroxyphenyl)-2-{5-(1,2,2-tricyanovinyl)-2-thienyl)ethenes as NLO chromophores, which constitute parts of the polymer backbone. Polyurethane 7 is soluble in common organic solvents such as DMF and DMSO. It shows a thermal stability up to 270 oC from TGA thermogram with Tg value obtained from DSC thermogram near 155 oC. The second harmonic generation (SHG) coefficient (d33) of poled polymer film at 1560 nm fundamental wavelength is 1.50 pm/V. Polymer 7 exhibits a thermal stability even at 5 oC higher than Tg, and no significant SHG decay is observed below 160 oC, which is acceptable for nonlinear optical applications. |
