Polystyrene macromonomer with boronic acid propanediol diester functionality prepared by ATRP for synthesis of comb-like polyphenylenes

Denzene-2,5-dibromomethyl-1,4-bis(boronic acid propanediol diester) was used as initiator in Atom Transfer Radical Polymerization (ATRP) of styrene in conjunction with CuBr/2,2'-bipyridine as catalyst. The resulted macromonomer, with a central benzene ring bearing cyclic boronic acid diester groups and polystyrene segments at each side, was used in combination with 1,4-dibromo-2,5-dimethylbenzene for a Suzuki coupling in the presence of Pd(PPh3)(4) as catalyst. The obtained polyphenylene, with alternating polystyrene side chains and methyl groups, has high solubility in common organic solvents at room temperature. The new polymer was characterized by H-1-NMR, IR and UV analysis. Thermal behaviour of the precursor polystyrene macromonomer and the final polyphenylene was investigated by DSC and compared.