Viscoelastic Phase Patterning in Artificial Protein Hydrogels

Viscoelastic forces can affect the dynamics of pattern formation during phase separation in polymeric materials. We programmed an artificial protein hydrogel to undergo viscoelastic phase separation above a critical temperature. Highly dynamic phase patterns that coarsened under the influence of viscoelastic stresses spontaneously emerged in these gels. Local oxidative crosslinking promoted by mild photobleaching could be used to initiate phase separation locally, enabling the creation of non-equilibrium patterns that evolved under the influence of surface tension and viscoelastic stresses to yield dynamic structures of controlled size and shape.