Polyelectrolyte Complex Materials

Polyelectrolyte complexation can be used in the self-assembly of a wide range of responsive, bioinspired soft materials ranging from dehydrated thin films, fibers, and bulk solids to dense, polymer-rich liquid complex coacervates. While the phase behavior of liquid-liquid phase separated complex coacervates has been studied for many years, our understanding of how factors like polymer chemistry alter the physical properties of the resulting coacervates is less well developed. Furthermore, a number of reports take advantage of coacervates as a processable liquid phase for fabricating solid films, fibers, etc. upon removal of salt. For these materials, it is an open question as to how the properties of liquid coacervates translate to those of a solid polyelectrolyte complex, and the role that polymer chemistry might play in these systems. We harness model copolymer systems to explore the ways in which polymer chemistry (e.g., backbone chemistry, charge group, neutral comonomers) and physical parameters such as length affect the mechanical response of both liquid and solid complexes, with an eye towards developing these materials for a range of future applications.