Thermally Activated Delayed Fluorescent Polymers

The development of organic light emitting diodes (OLEDs) based on fluorescent materials has made a great progress in improving light emitting efficiency and full range colors. But it still encounters the low singlet excitons generation ratio of 25% in device. As a solution to this problem, thermally activated delayed fluorescent (TADF) materials can convert the triplet excitons to the singlet ones, thus achieve theoretically 100% exciton utilization efficiency. Up to now, the small TADF molecules have achieved great breakthrough in realizing high external quantum efficiency and full color range including blue, green, and red. While the OLED devices based on macromolecules possess the inherent advantages of simplicity and lower cost in the rapid deposition of large areas at room temperature, especially on large flexible substrates, it is still relatively difficult to realize TADF effect in macromolecules, although several reports have partially confirmed them promising candidates for practical applications. This review summarizes the recent progress in the field of TADF polymers and their device performances in OLEDs, and also gives some outlooks for the further exploration in this field at the end of this paper.