Synthesis and photoluminescence of linear and hyperbranched polyethers containing phenylquinoxaline units and flexible aliphatic spacers

Ultrahigh‐molecular‐weight linear polyethers were prepared through a reaction between the phenylquinoxaline monomers 2,3‐bis(4‐hydroxyphenyl)‐6‐fluoroquinoxaline and 2,3‐bis(4‐hydroxyphenyl)‐6‐(α,α,α‐trifluoromethyl)quinoxaline and 1,12‐dibromododecane. A new hyperbranched polyether containing a phenylquinoxaline moiety was also prepared from a new self‐polymerizable AB2 monomer, 2,3‐bis(6‐bromohexyloxyphenyl)‐6‐(4‐hydroxyphenyloxy)quinoxaline. All the polyethers were amorphous and soluble in polar aprotic solvents. Their solution‐cast thin films were light yellow, ductile, and optically transparent. The polymers were thermally stable up to 350 °C and had glass‐transition temperatures in the range of 25–83 °C, which depended on the architecture and monomer structure. The monomers and polymers displayed fluorescence maxima in the blue‐light region in the range of 431–449 nm with relatively narrow peak widths; this indicated that they had pure and intense fluorescence.