Coacervate gel composites: Phase behavior and topologically frustrated dynamical hierarchy

We report the discovery of a novel coacervate gel composite state and experimental results on the phase behavior and dynamics of this state. This state is qualitatively different from the traditional coacervate liquid states composed of oppositely charged macromolecules formed via liquid-liquid phase separation. The cross-linking of one of the components of our system induces a new dynamical state for the oppositely charged guest polymer. In this state, the guest molecule is topologically frustrated exhibiting a hierarchy of internal chain dynamics, and is non-diffusive, although the water content in the coacervate gel is very high. In addition, we find rich phase behaviors as a function of cross-linking of one component, charge stoichiometry, pH, and salt concentration. An interlude of an coacervate-emulsion phase prior to the gel formation and its response to cross-linking at different experimental control variables will be presented.