Synthesis of Novel Y-Type Nonlinear Optical Polyurethane Containing Tricyanovinylthiophene with High Thermal Stability of Dipole Alignment

• Published in: Molecular Crystals and Liquid Crystals Vol. 504; no. 1; pp. 204 - 211
• Main Authors: Jang, Han-Na, No, Hyo Jin, Lee, Ju-Yeon
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis Group 01.01.2009; Taylor & Francis Ltd
• Subjects: differential scanning calorimetry (DSC); NLO; Polymer films; Polyurethane; relaxation of dipole alignment; SHG coefficient; Solvents; thermogravimetric analysis (TGA)
• ISSN: 1542-1406; 1563-5287; 1527-1943
• DOI: 10.1080/15421400902950196

A novel Y-type polyurethane 7 containing 1-(2,4-dioxyethoxy)phenyl-2-{5-(1,2,2-tricyanovinyl)-2-thiophenyl)}ethenyl groups as nonlinear optical (NLO)-chromophores, which are components of the polymer backbones, was prepared. Polyurethane 7 is soluble in common organic solvents such as DMF and DMSO. It showed a thermal stability up to 280°C in TGA thermogram and the T g value obtained from DSC thermogram was around 163°C. The second harmonic generation (SHG) coefficient (d 33 ) of poled polymer film at 1560 nm fundamental wavelength was around 3.72 × 10 −9 esu. The dipole alignment exhibited a thermal stability up to near T g , and there was no SHG decay below 150°C due to the partial main-chain character of the polymer structure, which is acceptable for nonlinear optical device applications.