Synthesis and photophysical properties of a charm-bracelet type C ₆₀-grafted PPV derivative

Synthesis and photophysical properties of a new soluble C ₆₀-grafted PPV polymer have been described. Fluorescence quenching of the PPV moiety in C₆₀-grafted PPV polymer was observed, suggesting the energy- and/or electron transfer within the polymer. The fluorescence decay profiles at around 500 nm of this polymer both in chloroform and benzonitrile display a single exponential decay giving the fluorescence lifetimes of 1.10-1.27 ns, which are slightly shorter than that of PPV (about 1.50 ns). The nanosecond transient absorption band of C₆₀-grafted PPV polymer was observed at 740 nm corresponded to the excited triplet state of C₆₀, which decreased in benzonitrile, indicating the existence of the extra decay path of the singlet excited state of the C₆₀ other than intersystem crossing. Upon heating this polymer exhibits typical semilunar liquid crystalline texture, being closely associated with its polymeric structure with long solubilizing alkoxy side chains.