Solid-supported synthesis of hyperbranched polymer with beta,beta-diethynylstyryl units

Two novel aromatic polyamide supports bearing aromatic bromine and i ine fu nctionality have been synthesised and tested for the solid-supported polyme rization of AB(2) type monomer 4-(5-hexynyloxy)-beta,beta -dibromostyrene v ia Pd-catalysed cross-coupling of vinyl halides and terminal acetylenes. It was found that the solid-supported polymerization leads to a decrease in m olecular weight and increase in the degree of branching from 17000-18000 g mol(-1) to 8000-4000 g mol(-1) and from 30-35% to 50-65%, respectively, com pared to solution polymerization. All other things being equal, the decreas e in molecular weight of hyperbranched polymer on solid-supported polymeriz ation is a function of the distance between adjacent active sites of the po lymer support. (C) 2001 Society of Chemical Industry