Estimating the Polydispersity of GPC Slices Due to Coeluting Comb-Polymers Synthesized by Grafting Monodisperse Side Chains Onto a Backbone Having Broad Molecular Weight Distribution

The molecular weight distribution, polydispersity and the distribution of side chains within a GPC-slice have been calculated for coeluting comb-shaped polymers. It is assumed that the polymers were synthesized by grafting monodisperse side chains onto a backbone having a broad molecular weight distribution. Despite the broad polydispersity of the backbone the polydispersity within a GPC-slice is rather narrow, as is the distribution of side chains. Consequently the effect of polydispersity on properties, which can be obtained by GPC coupled with molar mass sensitive detectors is negligible. However, this result is true only for the specific branching mechanism investigated.