Expanding the structural diversity of polyelectrolyte complexes and polyzwitterions

Charged (macro)molecules are essential components in natural materials and organisms; thus the rational design of biomimetic materials requires a holistic understanding of structure–property relationships in charged systems. We discuss recent progress in uncovering such relationships for polyzwitterions and polyelectrolyte complexes, with emphases on the synthetic strategies that were employed in systematic studies. For polyelectrolytes, discussion is confined to the effects that structural variations in polycation and polyanion structure have on the fundamental phase behavior of the corresponding polyelectrolyte complexes. In the field of polyzwitterions, both fundamental and applied properties are discussed in relation to chemical structure. Finally, we present an overview of promising chemistries that will expand the structural landscape of charged macromolecules with the aim of stimulating new research to further uncover and understand the fundamental design principles for these materials.