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The Structure and Dynamics of Flexible Polyelectrolyte Combs

A. Papagiannopoulos·T. A. Waigh·C. Fernyhough·T. Hardingham·M. Heinrich
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Abstract

The structure and dynamics of a range of polystyrene sulphonate comb polyelectrolytes with well defined chain architectures were examined with static light scattering, dynamic light scattering, small angle neutron/X-ray scattering, particle tracking microrheology and diffusing wave spectroscopy. The chains adopted extended cylindrical conformations in dilute solutions. In semi-dilute solutions a universal behaviour was found for the correlation length (X) on the monomer concentration (c), X=(3.0/b)c^-0.47, independent of the comb architecture (b is the monomer size). The high frequency viscoelasticity (104-106Hz) is found to be in agreement with a model for the Rouse dynamics of the chains and is again independent of the architecture of the combs. However the architecture had a significant impact on the low frequency viscosity of the solutions and the particle tracking data was in good agreement with a dynamic scaling theory for the unentangled dynamics of the combs. Analogous results are found with the biological comb polyelectrolyte aggrecan.

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A. Papagiannopoulos, T. A. Waigh, C. Fernyhough, T. Hardingham, M. Heinrich. 2005-08-27. The Structure and Dynamics of Flexible Polyelectrolyte Combs. https://arxiv.org/abs/cond-mat/0508655

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