Synthesis and electroluminescent properties of polyurethane with stilbene dye pendant

A polyurethane (PU) derivative with a stilbene side chain was prepared from 4-cyano-4'-[N,N- bis (2-hydroxyethyl) amino] stilbene and 2,4-tolylene dii socyanate (2,4-TDI). The stilbene dye was synthesized by Wittig reaction of 4 - [N,N-bis (2-hydroxyethyl) amino] benzaldehye with (4-cyanobenzyl) trip henyl phosphonium chloride. The molecular structures were confirmed by elem ental analysis, FT-IR and 1H-NMR spectroscopy and the thermal properties we re investigated by DSC. The PU derivative exhibits strong photoluminescence (PL) in the green spectral region peaking at 510 nm. Single-layer electrol uminescent devices with ITO and MgAg as electrodes were fabricated via spin -coating from PU solution.