Hydrodynamic properties and unperturbed dimensions of polycyclohexyl and polyphenyl methacrylates in various solvents

Intrinsic viscosity, sedimentation, light scattering and osmotic pressure measurements have been made on dilute solutions of polycyclohexyl (PCy) and of polyphenyl methacrylates (PPh). Relations between (η), (S₀), second virial coefficient and molecular weight have been established. The applicability of the different theories (Stockmayer-Fixman, Kurata-Stockmayer, Fox-Flory, Cowie, Berry, Kamide-Moore) for the determination of the unperturbed dimensions from the viscosity data is discussed; Berry's relation fits best the experimental data. These dimensions calculated from the sedimentation data (Cowie-Bywater) and from the second virial coefficient data (Krigbaum) agree with those obtained by viscosity. The flexibility factor σ obtained for the two polymers is high, 2·5 (PCy) and 2·8 (PPh), confirming previous results on poly-β-naphthyl and polydecahydro-β-naphthyl methacrylates.⁽¹⁾. The fact that the aromatic polymers have higher σ values than the corresponding saturated polymers may be due to a specific interaction between the aromatic groups and to their higher rigidity.