Key points are not available for this paper at this time.
Keto defect sites play a key role as the source of low-energy emission bands in polyfluorene type materials. The formation of fluorenone defect sites can be regarded as a dominant degradation mechanism in light-emitting devices based on polyfluorenes. The superiority of difunctionalization (see Figure) at the methylene group in –CR2– bridged polyphenylene and polyarylene derivatives is illustrated.
List et al. (Mon,) studied this question.