UC Santa Barbara

Appropriate deciphering and translation of sequence-dependent function in proteins is inspired by the cation–π interaction that is increasingly implicated in marine adhesives and membraneless organelles. A simplified cation-methylene-phenyl (C-M-P) sequence which enables triggerable poly(ionic liquid) coacervation is reported for the first time. Synthesis of the C-M-P structure motif requires only a one-step quaternization, which is facile compared to the linear sequence of distinct repeating units in model proteins and sequence-controlled polymers. The C-M-P code confers modular coacervation and advanced wet adhesion to task-specific copolymers. It allows for exceptional underwater adhesion to various submerged substrates including glass (≈1 MPa) and porcine skins (140 KPa), paving the way for prospective adhesive applications in physiological saline and underwater marine salvage. This work introduces a powerful code that, in addition to combining the advantageous adaptive adhesive and phase properties of proteins, reduces the complexity in sequence design for programmable coacervates.