Fullerene Substitution of Donor/Acceptor Branched Disubstituted Polyacetylenes: Significantly Accelerated Polymerization by the C 60 Pendant

A novel type of soluble donor/acceptor branched disubstituted polyacetylene ( PA–C 60 ) bearing C 60 and soft pentyl moieties in side‐chains was synthesized successfully. The product has been characterized by FTIR, 1 H NMR, 13 C NMR, CH COSY, UV‐vis, and fluorescence spectroscopies, confirming its branched polymeric structure comprising polyacetylene chains and covalently bound C 60 cages in side‐chains. Surprisingly, completely different from the conventional metathesis polymerization of acetylenes, it is found for the first time that the disubstituted monomer 4 can be polymerized within a very short reaction time (up to 1.5 min) and the molecular weight of the synthesized PA–C 60 is independent of the reaction time. A plausible interpretation is proposed to understand the rapid polymerization reaction accelerated by the C 60 pendant. The optical properties of PA–C 60 were studied by UV‐vis absorption and fluorescence spectroscopies, which indicated that the fluorescence of PA–C 60 is significantly enhanced compared to monomer 4 , presumably due to its branched structure. SEM studies on the thin film morphology of PA–C 60 in comparison with monomer 4 suggested the successful polymerization of monomer 4 and revealed that PA–C 60 has a much smoother morphology than the aggregated morphology of monomer 4 .