High Quantum Yield Photoluminescence of New Polyamides Containing Oligo-PPV Amino Derivatives and Related Oligomers

The synthesis and the chemical physical characterization of new photolu- minescent (PL) chromophores and polymers are reported. Chromophores (oligo-PPV symmetric derivatives ending with amino groups) are strong blue emitters with a PL quantum yield of $70% in dioxane solution. They have been used to prepare poly- amides by reaction with aliphatic acyl dichlorides in which emitting and non emit- ting units are alternated. PL properties of the synthesized polyamides have been evaluated in solution and reveal a strong blue emission (PL quantum yield $60%), To increase the solubility of these systems, oligomers have been purposely prepared and then characterized. They show a peculiar white emission when excited in DMF solution; to get insight into this interesting behavior, asymmetric monoacetylated chromophores have been prepared as model compounds for the chromophoric end groups of the polyamide chains. The emission spectra of these compounds reveal a broad excimeric yellow emission which is responsible, along with the blue emission of the inner chromophoric units, of the overall white emission of the oligomers.