Electroactive and conducting star-branched poly(3-hexylthiophene)s with a conjugated core

A new star structured regioregular poly(3-hexylthiophene) with a conjugated hyperbranched poly(triphenylamine) as the core has been shown to be electroactive and able to attain high levels of conduction up to 100 S/cm when doped. A hyperbranched poly(triphenylamine) was synthesized by a Negishi coupling reaction from tris(4-bromophenyl)amine with the terminal bromo group on the hyperbranched polymer subsequently converted to a bromothiophene. This functionalized hyperbranched polymer was used as a core for the synthesis of a star structured regioregular poly(3-hexylthiophene). The star polymer has a fully conjugated system with conjugated arms of poly(3-hexylthiophene) attached to a conjugated core of poly(triphenylamine). The solution, optical, and thermal properties of the polymers were investigated by SEC, UV-vis spectroscopy, TGA, and DSC. The results indicated that with the branched star structure the polymer retained a high degree of structural order as is typical for regioregular poly(3-alkylthiophene)s.