Synthesis, light emission, and photo-cross-linking of luminescent polyacetylenes containing acrylic pendant groups

New poly(1-phenyl-1-alkyne)s bearing acrylic pendants (–{(C6H5)CC[(CH2)mOCOCHCH2]}n–; P1(m), m=3, 9) with high molecular weights are synthesized in high yields by WCl6–Ph4Sn catalyst. The structures and properties of P1(m) are characterized and evaluated by IR, NMR, TGA, UV, and PL analyses. All the polymers are solution-processable and thermally stable (Td≥380 °C). Upon photoexcitation, the polymers emit strong blue lights with emission efficiencies (>40%) comparable to that of poly(1-phenyl-1-octyne), an emissive disubstituted polyacetylene. No excimeric absorption and emission are observed in the thin films of the polymers. The acrylic moieties of P1(m) are readily cross-linked by UV irradiation without harming their optical properties, which may enable them to find high-tech applications in photoresist, luminescent patterning, and light-emitting diodes.