Abstract: The present invention relates to novel polymers comprising a repeating unit(s) of the formula (I) wherein at least one of the substituents R1, R2, R3, R4, R5, R6 and R7 is a group -(Sp)x1-HEI, wherein Sp is a spacer unit, HEI is a group (HEII), which increases the hole-injection and/or hole-transport properties of the polymers; or a group (HEIII), which increases the electron-injection and/or electron-transport properties of the polymers, or a group (HEIIII), which increases the hole-injection and/or hole-transport properties of the polymers and the electron-injection and/or electron-transport properties of the polymers, x1 is 0, or 1, and their use in electronic devices. The polymers according to the invention have excellent solubility in organic solvents and excellent film-forming properties. In addition, high charge carrier mobilities and high temperature stability of the emission color can be observed, if the polymers according to the invention are used in polymer light emitting diodes (PLEDs).