Where are the End-Groups in a Hyperbranched Polymer?

The location of the end-groups in hyperbranched polymers is modelled by considering two synthetic strategies. The first synthesis is to make linear chains, and then link these chains. The second strategy is to sequentially add multifunctional monomers. The first strategy represents hyperbranched polymers synthesized by living radical methods, whereas the second represents polycondensations at low conversion. The high-conversion case is also considered. The present analysis suggests that sequential addition of monomers places more end-groups at the polymer's surface than synthesis by linking chains. If the end-groups are catalysts, synthesis by the addition of monomers should give fewer inaccessible catalysts.