Synthesis and solution properties of rodlike polyelectrolytes

The synthesis and the solution behavior of rigid, rodlike cationic polyelectrolytes having (i) poly(p-phenylene) backbones and (ii) main chains composed of 4,4-bis(2,2':6',2-terpyridine)2',5'-dihexyl-p-terphenyl moieties and ruthenium(II) centers are presented. All these polymers are shown to have a homogeneous constitution and degrees of polymerization of up to P n ≃ 70. Their solution properties were analyzed using viscosimetry, small-angle X-ray scattering (SAXS) and osmometry. Pronounced polyelectrolyte effects were found in salt-free solutions using viscosimetry. Small-angle X-ray scattering demonstrated directly the strong correlation of the counterions and the macroions. The osmotic coefficients measured in salt-free solution as function of polyelectrolyte concentration were found to be lower than predicted by the cell model.