Synthesis Of Pyrene And Tetraphenylethene Based Polysiloxane As Blue Phosphorescent Host

Researchers believe that OLEDs will be the next-generation light source for its self-illuminating, eco-friendly and power saving. So it has very important significance for OLEDs material exploration, particularly research on phosphorescent materials, which can improve the luminous efficiency of OLEDs greatly. One method to modify the performance of materials is incorporate photovoltaic materials to the silicon-oxygen bond which was used as a skeleton.Linear polysiloxane with pyrene (PSiPy) and tetraphenylethene (PSiTPE) as side groupsand ladder polysiloxane (Lad-PSiPy) with pyrene side groups were synthesised successfully in this work.PSiPydisplays a high decomposition temperature (Td=343℃) and glass transition temperature (Tg=167℃).It also exhibits good film-forming ability, fine transparency, high morphological stability and high triplet energy level (ET=3.0 eV).UV-Vis absorption spectra shows the absorptionhad slight red-shiftand intensity increase for the decrease of solubility and the increase of solvent polarity. And PL spectra shows emission enhance for AIEE in its nanoparticlestate compared to its solution state. HOMO (-5.123 eV) and LUMO (-2.023 eV) of PSiPy were calculated by CV test. Lad-PSiPy and its monomer also exhibit AIEE property. And the largerintermolecule resistance of Lad-PSiPy results in a weak AIEE than its monomer, while Lad-PSiPydisplays high thermal decomposition temperature (Td=343℃).What’s more, monomer shows a big red shift in its solid state compared to its solution state.These results reveal that using polysiloxane to modify small molecule fluorophores is a promising approach to improve the physical properties while maintaining other properties.