The above results drove us to further explore PDI-based TSCT polymer systems, by introducing electron donors of higher electron density. Polycyclic aromatic monomers (PAMs) proved to induce strong charge transfer to imide-based electron acceptors. Using PDI-tetraBr as the initiator, we first polymerized 2-vinylnaphthalene (2VN) as the donor monomer and obtained a homopolymer, PDI-poly2VN (Figure nm for DP 20). These results indicate that the polymeric naphthalene units can provide stronger charge transfer to the PDI scaffold compared to styrenic units. This was further confirmed by the noticeable redshifted absorption spectra of poly2VN in DMF, DMF/H2O = 5/95 (v/v), and of the polymer thin films compared to PDI-tetraPS (Figure ).