Oligo- and poly(fullerene)s for photovoltaic applications: Modeled electronic behaviors and synthesis.
Résumé
The atom transfer radical addn. polymn. (ATRAP) of fullerene to give poly(fullerene)s (PFs) for org. electronics is explored. Quantum chem. maps the expected electronic behavior of PFs with respect to common electron acceptors, namely fullerene, phenyl-C61-butyric acid Me ester and its bis-adduct, and mono- and bis-indine-fullerene derivs. Surprisingly, it is found that PFs should demonstrate electron affinities and LUMO energy levels closer to the bis-derivs. than the mono-adducts, even though only one C60 double-bond is used in PF chain formation. A self-consistent library of PFs is synthesized and a correlation between structural characteristics and mol. wts. is found. While comonomers with -OC16H33 linear side-chains lead to the highest known ATRAP mol. wts. of 21000 g mol-1, like-for-like, branched side-chains permit syntheses of higher mol. wts. and more sol. polymers. Of the series, however, PFs with -OC12 side-chains are expected to be of the greatest interest for opto-electronic applications due to their ease of handling and highest regioregularity. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017. [on SciFinder(R)]