Novel conjugated polymers employing the binding of polyfluorene derivatives and C₆₀

New polyfluorene (PF)-based conjugated polymers, PClBEHF, PClBEHF-co-PDEHF, PN₃BEHF, PN₃BEHF-co-PDEHF, PEHPBF, PC₆₀BEHF, PC₆₀BEHF-co-PDEHF, and PEHPBF⁺PCBA^- containing chloro, azido, piperidine, and fullerene (C₆₀) groups as pendants, were synthesized. In the case of PC₆₀BEHF and PC₆₀BEHF-co-PDEHF, the C₆₀ moiety was introduced by using covalent bond formation between the azido group and C₆₀. PEHPBF⁺PCBA^- was synthesized by using ionic bond formation between the piperidinium cation of PEHPBF and carboxylate anion of PCBA. The PL and EL spectra of PClBEHF, PClBEHF-co-PDEHF, PN₃BEHF, PN₃BEHF-co-PDEHF, and PEHPBF exhibited red-shifted and broad peaks caused by the aggregation which was induced by the increasing interchain interaction due to the polar pendants. After binding with C₆₀, covalently and ionically, the photovoltaic properties of PC₆₀BEHF, PC₆₀BEHF-co-PDEHF, and PEHPBF⁺PCBA^- were studied. PL was quenched completely, which indicates photo-induced charge transfer from PF to pendant C₆₀. Even though photovoltaic effects did not occur in short circuit condition, blending with MEH-PPV as the ratio of 1:1 generated the photovoltaic effects.