Synthesis of ring-structured polysiloxane as host materials for blue phosphorescent device

A ringed polysiloxane with a side chain of dibenzothiophene groups (BS-PSQ) is successfully synthesized as confirmed by MALDI-TOF MS and H-1-NMR. DSC, TGA, AFM and spectra reveal its good film-forming ability, high thermal and morphological stability, and good miscibility with the dopant FIrpic. In addition, it also has a high triplet energy and a wide band gap. The BS-PSQ may be used as a host for the blue light emitter iridium complex FIrpic. The electrophosphorescent device based on BS-PSQ as the active layer exhibits typical blue emission, and the performance of the device is superior to that of any other POSS-based host material reported and also to some of the small molecular host materials.