Transport coefficients of helical wormlike chains. 4. Intrinsic viscosity of the touched-bead model

Chain Stiffness and Excluded-Volume Effects in Polyelectrolyte Solutions: Characterization of Sodium Poly(2-acrylamido-2-methylpropanesulfonate) in Aqueous Sodium Chloride

“…The differences were at most a few %; note that ½ 0 is insensitive to q (or q app ) for very short chains, for which excluded-volume effects are negligible. At 0.5 M, q app appreciably decreases only for low M and the effect on [] is insignificant throughout the entire C and the theoretical curves computed from the theory of Yoshizaki et al 23 for unperturbed wormlike touched-bead chains and the QTP theory [12][13][14] (eqs 1-6) for excluded-volume effects. For clarity, the theoretical values (discrete for low molecular weights) at the respective salt concentrations are represented by continuous solid lines and those for one and two beads are connected by dashed straight lines.…”

“…The molecular weight dependence of [] and that of hS 2 i z for Na PAMPS in 0.05 and 0.5 M aqueous NaCl are described by the known expressions [23][24][25][26] for unperturbed wormlike chains and excluded-volume effects in the quasi-two-parameter scheme [12][13][14] with a degree of accuracy similar to that known for nonionic flexible polymers.…”

“…We analyze the viscosity data in Figure 6 by a combination of Yoshizaki et al's theory 23 for the intrinsic viscosity ½ 0 of an unperturbed wormlike touchedbead chain and the QTP theory [12][13][14] for the viscosity expansion factor . The former theory contains three parameters, the (total) persistence length q, the contour length L, and the bead diameter d; L is related to the molecular weight M by M=M L , with M L being the molar mass per unit contour length of the chain.…”

“…If the parameters from [] are used for hS 2 i z , the theoretical line for C s ¼ 0:5 M in Figure 5 shifts downward by about 8%. The resulting discrepancy is plausible, in that Yoshizaki et al's theory 23 in the coil limit, equivalent to the Kirkwood-Riseman theory, 27 overestimates [] (or the Flory viscosity factor) by 3-22%. 28,29 The perfect agreement between the parameter sets from [] and hS 2 i z at C s ¼ 0:05 M may be somewhat fortuitous, even though the theoretical error diminishes as the chain becomes stiff.…”

Fine characterization of oligomers and polymers in dilute solution

“…It may be expected that such a difference is also reflected in the behavior of steady-state transport properties, such as the intrinsic viscosity ½Z and translational diffusion coefficient D. Therefore, we further determine the two transport properties from viscosity and dynamic light scattering measurements for a-PaMS and a-PS, and compare the results with the HW theory in order to confirm whether the above expectation is true or not. We note that for the theoretical evaluation of the transport properties for flexible polymers on the basis of the HW chain model, we need another parameter, i.e., the bead diameter d b , to express the hydrodynamic chain thickness of the HW model in addition to the four basic model parameters [1,15,16]. Fig.…”