For example, oligonucleotides and helical polypeptides of varying lengths are being extensively investigated. The motions of molecules in solutions in which they interact strongly is of great interest in polymer science since most molecules are processed under these conditions. For neutral polymers these interactions occur in the semidilute and concentrated regions. For polyelectrolytes, molecules may interact strongly in low ionic strength solutions at relatively low concentrations because of unshielded electrostatic interactions. Both neutral and charged systems are being studied by theoretical and experimental techniques, including dynamic light scattering, small angle neutron scattering, transient electric birefringence decay and x-ray photon correlation spectroscopy.
Composite liquids are a ubiquitous class of materials which contain polymers, particles and solvent.
They are used, among other things, as ceramic precursors, lubricants, paints and coatings, adhesives and in chromatographic columns. Due to their complexity and the lack of adequate model systems, the interactions between the species in such systems are not well understood. Rod-coil liquids are liquids composed of a rod polymer, a coil polymer and a solvent.