Synthesis and Photophysical Properties of a Hyperbranched Trimethylsilyl Substituted Poly(phenylene vinylene) Derivative

Abstract

A novel trimethylsilyl substituted hyperbranched conjugated poly(phenylene vinylene) (Hyper-PBTMS-PPV) was synthesized through the Wittig polycondensation polymerization. Hyper-PBTMSPPV has good solubility in common organic solvents and showed good thermal stability up to 402 °C with less than 5 wt% weight loss. The photophysical properties of Hyper-PBTMS-PPV film are investigated and compared with trimethylsilyl-containing linear poly(1,4-phenylene vinylene) (Linear-PBTMS-PPV). An absorption maximum of Hyper-PBTMS-PPV film was determined at 335 nm which was far blue-shifted than that of Linear-PBTMS-PPV (380 nm). Hyper-PBTMS-PPV film showed blue photoluminescence (PL) peak at 449 nm. In addition, Hyper-PBTMS-PPV film exhibited almost no long wavelength emission peaks even the film was annealed at 120 °C for 30 min in air condition. High PL efficiency (Φfilm = 0.80) and no aggregate or excimer emission of Hyper-PBTMS-PPV film are due to the inhibition of intramolecular or intermolecular interaction by the introduction of the hyperbranched network into the trimethylsilyl-containing poly(phenylene vinylene) backbone.