https://doi.org/10.1351/goldbook.09604
Parameter characterizing the branched architecture of a hyperbranched polymer, which is equal to unity for a polymer that contains no linear or semi-dendritic constitutional repeating unit and is equal to 0 for a polymer that contains no dendritic or semi-dendritic constitutional repeating unit.
Notes:
- Several definitions of the degree of branching have been proposed for hyperbranched polymers obtained by polycondensation of \({\rm{AB}}_2\mbox{-}\rm{type}\) monomers and for those obtained by polycondensation of more complex monomer systems. The definition by Hölter et al. is: \(D_{\rm{br}} = 2 x_{\rm{D}}/(2 x_{\rm{D}} + x_{\rm{L}})\), where \(x_{\rm{D}}\) and \(x_{\rm{L}}\) are the mole fractions of dendritic and linear units, respectively.
- The degree of branching of a dendrimer is equal to one. However, a polymer with the degree of branching equal to one is not necessarily a dendrimer. It can be a hyperbranched polymer, since the degree of branching does not per se take into account the regularity and symmetry of the molecules that compose it.
- The degree of branching of a linear polymer is equal to 0.