Persistence Length of Dendritic Molecular Brushes

On the basis of mean-field theory, we predict that molecular brushes with dendritic side chains ("dendronized polymers") may exhibit the behavior of semirigid polymers capable of lyotropic odering. The apparent persistence length of these molecular brushes is governed by the interactions between dendritic grafts and may significantly exceed the characteristic brush thickness. Compared to bottle-brushes with linear grafts, manifestation of the induced rigidity in molecular brushes with dendritic branches is expected at smaller degrees of polymerization of the grafts. Under good solvent conditions, the induced rigidity depends solely on the number of side chain monomers per unit length of backbone and the second virial coeffcient of monomer-monomer interactions, irrespective of graft topology.