An Alternating Copolymer of a Tetrapeptide and a Tetrathiophene Prepared by a Click Reaction: A Study of the Synthesis and Assembly Behavior

Alternating copolymers of an oligopeptide (N₃‐GVGV‐N₃, where G: glycine; V: valine) and an oligothiophene (5,5′‐bis(ethynyl)‐3,3'‐dioctyltetrathiophene) are prepared by click chemistry. The experimental results discover that these copolymers exhibit strong molecular‐weight‐dependent self‐assembly behaviors. The copolymer P1 with the lowest weight‐average molecular weight ( = 7400 g mol^?1), assembles into well‐ordered fibrous nanostructures. P3 ( = 16 980 g mol^?1) assembles into nano­balls. P2, which has the medium between P1 and P3, ( = 14 800 g mol^?1), exhibits more‐complicated self‐assembly behaviors, more like a transition state between the other two. All of the results suggest the self‐assembly ability of these oligopeptide segments might be the major reason for the nano‐structure evolution.