Highly fluorescent mono‐substituted poly(arylacetylene)s containing tolane chromophores

<jats:title>Abstract</jats:title><jats:p>A new class of highly fluorescent mono‐substituted polyarylacetylenes (<jats:bold>P1–P3</jats:bold>) has been successfully prepared with good yields and high molecular weights from a series of phenylethynylene‐substituted arylacetylenes (<jats:bold>M1–M3</jats:bold>), using W‐based catalyst. These polymers are readily soluble in common organic solvents (e.g., THF, toluene, and chloroform) and thermally stable up to ∼350 °C. Both <jats:sup>1</jats:sup>H NMR and IR studies confirmed that all the monomers were selectively polymerized at the terminal triple bond. The <jats:sup>1</jats:sup>H NMR results showed that both <jats:bold>P1</jats:bold> and <jats:bold>P2</jats:bold> have essentially <jats:italic>trans</jats:italic>‐polyene backbone structures, while <jats:bold>P3</jats:bold> contains significant amounts of both <jats:italic>cis</jats:italic>‐ and <jats:italic>trans</jats:italic>‐structures. Coincidently, the photoluminescence (PL) intensity of <jats:bold>P3</jats:bold> is also much lower than both <jats:bold>P1</jats:bold> and <jats:bold>P2</jats:bold>. Nevertheless, the PL intensity of <jats:bold>P1–P3</jats:bold> are all much higher than that of <jats:bold>PPA</jats:bold>, suggesting that the introduction of phenylethynylene group to the phenyl rings of <jats:bold>PPA</jats:bold>s have made the in general nonemissive <jats:bold>PPA</jats:bold>s to become highly photoluminescent. Most interestingly, although <jats:bold>P1</jats:bold> did not contain any substituent group on its tolane pendant group, it is already highly soluble in common organic solvent and emitting blue fluorescence (416 nm) with a reasonably good quantum yield (0.36). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5483–5498, 2008</jats:p>