(364f) Spontaneous Self-Assembly and Micellization of Random Copolymers in Organic Solvents

Spontaneous self-assembly of random and statistical copolymers in solution is unusual due to the structural irregularity of the copolymer chain and close proximity of short incompatible segments. This study describes the first observation of supramolecular structures such as micelles and vesicles formed by a random copolymer in organic solvents. Upon dissolution in methanol or tetrahydrofuran, the random copolymer poly(trifluoroethyl methacrylate-random-methacrylic acid) forms small spherical micelles, worm-like assemblies and large vesicles spontaneously. Self-assembly is driven by the high incompatibility between the fluorinated and acidic, partially ionized repeat units. Micelle size can also be altered by the addition of metal ions, which interact with the carboxylic acid groups on methacrylic acid through complexation or Coulombic forces. These findings demonstrate an easy, single-step approach to creating nano-scale structures with tunable size and morphologies in organic solvents from easily synthesized random copolymers, with potential applications in coatings, selective membranes, catalysis, and drug delivery.