Novel nonlinear optical polymers based on poly(1,4-phenylenevinylene)

Abstract

A novel poly(1,4-phenylenevinylene) (PPV) derivative containing a nonlinear optical (NLO) moiety was synthesizedvia the methoxy-precursor pathway to give a highly rigid structure which still maintained good processability. Poly[2-butoxy-5-(2-{ethyl-[4-(4-nitrophenyldiazenyl)phenyl]amino}ethoxy)-1,4-phenylenevinylene] (PBDR1PV), containing a Disperse Red 1 (DR1)-type chromophore, was characterized by conventional spectroscopic methods (UV–VIS, FT-IR, NMR) and by thermal analyses. The synthetic approach has been applied for the preparation of high optical quality films for nonlinear optical applications. PBDR1PV films showed a high resonant d₃₃ value of 50 pm V^–1 when measured using the second harmonic generation (SHG) method. The nonlinearity of PBDR1PV was very stable at 90 °C for a month without detectable loss. In addition to second-order NLO properties, the PBDR1PV film showed third-order NLO properties simultaneously and the measured chi;⁽³⁾ value was found to be 2.5×10^–12 esu.