Mean square radius of gyration and hydrodynamic radius of jointed star (dumbbell) and H‐comb polymers

Abstract Equations for the mean square radius of gyration and the hydrodynamic radius for jointed stars (dumbbells) and H‐combs are derived, based on random flight statistics for each subchain. Comparision with literature data on computer simulations and experimental data for H‐combs show good agreement for the g‐value of the mean square radius of gyration even in good solvents. This suggests that for the mean square radius of gyration the relative dimension of a H‐comb relative to the linear molecule of the same degree of polymerization is not altered significantly by long range interactions, as in the case of star polymers. For the hydrodynamic radius the situation is different. Fair agreement is found when comparing our results with viscosity measurements under θ conditions, while in good solvents the viscosity of the branched molecule is more reduced than predicted by our results.