Synthesis and characteristics of polymacromonomers composed of alternating binaphthalene-phenylene main chain and polystyrene side chains

Well-defined polystyrene (PSt) based polymers containing middle- or end-chain 2,5- or 3,5-dibromobenzene moieties, prepared by Atom Transfer Radical Polymerization (ATRP) were implied in Suzuki type couplings with 1-naphthalene boronic acid. The resulting polymers, containing a conjugated sequence with 1-naphthyl groups at the extremities, were used as macromonomers in chemical oxidative polymerization in the presence of anhydrous FeCl₃. Polyarylenes, with a hairy-rod structure, having binaphthyl groups in the main chain and the respective PSt chains as lateral substituents, were obtained.All the starting, intermediate or final polymers were structurally analyzed by spectral methods (¹H NMR, IR) and GPC measurements. Thermal behavior of the macromonomers and final polymers was investigated by Differential Scanning Calorimetry (DSC) analyses. Optical properties of the polymers were followed by UV and fluorescence spectroscopies. The absorption spectra of the polymers indicate only a limited extend of conjugation as compared to the naphthalene functionalized polystyrenes. However, in the emission spectra of the polymers, a bathochromic shift with respect to the monomers was observed in all cases.