Electrostatic complexation of conjugated and bottlebrush polyelectrolytes forms printable conductive inks

Electrostatic complexation enables blending of otherwise immiscible polymers by liquid–liquid phase separation, forming a polymer-rich phase suitable for processing. We explored design rules for processable complexes using electrically conductive conjugated polyelectrolytes (CPEs) and mechanically tunable bottlebrush polyelectrolytes (BPEs). Sulfonated polythiophene and self-doped sulfonated PEDOT were examined to study how charge fraction influences compatibilization, printability, and properties. The resulting CPE: BPE complexes exhibited rheology suitable for direct ink writing into thick patterned structures. Upon drying, they combined electrical conductivity with elasticity and adhesiveness, enabling applications in soft, thick, semiconducting materials.