Well-Defined Amphiphilic Block Copolymers and Nano-objects Formed in Situ via RAFT-Mediated Aqueous Emulsion Polymerization

A hydrophilic poly(methacrylic acid-co-poly-(ethylene oxide) methyl ether methacrylate) copolymer with a trithiocarbonate reactive group was used in the free-radical, batch emulsion polymerization of styrene. It allowed fast polymerizations and high final conversions to be achieved, and the parameters for a good control over the formation of well-defined amphiphilic diblock copolymers were identified. These diblock copolymers self-assembled in situ into nano-objects of various morphologies upon chain extension. Achieving a good control over the formed diblock copolymers was shown to be an important step toward a better understanding of the parameters that affect the shape and size of the self-assembled objects, the ultimate goal being the ability to predict and fine-tune them on purpose.