Patent ID: 11525038

Abstract:
A crosslinked polyimide, a polyimide film and a method for preparing thereof, an organic light emitting diode (OLED) device. 4,40-diamino-400-N-carbazolyltriphenylamine and 1,2,4,5-cyclohexanetetracarboxylic dianhydride and a p-xylylenediamine crosslinker are introduced in the present invention. The introduction of a diamine monomer with a large volume of pendant groups increases an asymmetry of the polyimide, destroys a close structure of the polymer, and reduces crystallization properties of the polypolymer, thereby effectively increasing its transmissibility. At the same time, a cross-linked agent, p-xylylenediamine, is introduced, and the cross-linked agent widens a molecular chain spacing, so that the polyimide molecule has a larger free volume. At the same time, the formation of cross-linked is beneficial to reduce a polarizability of the molecule, thereby reducing a dielectric constant of the material. An OLED device with a novel low dielectric constant and high transmittance is prepared in this way.