Electrostatic complexation of conjugated polyelectrolytes

The development of blends of conjugated polymers is helpful for applications including stretchable electronics, bioelectronics, and electrochemical systems. Electrostatic complex coacervation of oppositely-charged polyelectrolytes has recently emerged as a versatile route to form processable, functional polymer blends of conjugated polyelectrolytes from solution. However, substantial differences in chain stiffness and redox activity among conjugated polyelectrolytes leave the design rules for complex coacervation unresolved. Recent progress towards understanding how electrostatic interactions of conjugated polyelectrolytes can be used to control the properties and processability of blends is presented. The phase behavior of blends of conjugated and non-conjugated polyelectrolytes and the resulting nanostructure in solidified form are discussed. Electrostatic complexation is found to be a powerful tool to tailor the photophysical and electronic transport properties of blends of conjugated polyelectrolytes. The potential space for applications of these processable blends is reviewed by a discussion of recent efforts to form stretchable conductors, battery binders, and bioelectronic devices.