Synthesis of polymer brushes composed of poly(phenylacetylene) main chain and either polystyrene or poly(methyl methacrylate) side chains

Novel cylindrical polymer brushes consisting of a highly cis-transoidal poly(phenylacetylene) main chain and either polystyrene (PS) or poly(methyl methacrylate) (PMMA) side chains were synthesized by the macromonomer method. Two phenylacetylene-terminated macromonomers, namely, M−PS (Mn = 1830) and M−PMMA (Mn = 1860), were prepared by atom transfer radical polymerization (ATRP) of styrene and methyl methacrylate, respectively, using acetylene-functionalized initiators. M−PS and M−PMMA were polymerized successfully with the [(nbd)RhCl]2/Et3N (2,5-norbornadiene) catalyst [Rh-1] to give high molecular weight polymer brushes, poly(M−PS) (e.g., Mw 1660 × 103) and poly(M−PMMA) (e.g., Mw 1480 × 103), respectively, according to GPC−RALLS. Further, well-defined poly(M−PS) (e.g., Mn 47 × 103, Mw/Mn 1.12) and poly(M−PMMA) (e.g., Mn 30 × 103, Mw/Mn 1.16) with narrow MWDs were obtained with an Rh-based living polymerization catalyst [Rh-2]. The present polymer brushes were yellow to orange due to the conjugated main ...