Amphiphilic gradient copolymers: synthesis and self-assembly in aqueous solution
Résumé
This chapter reviews the methods that employed to form well‐defined gradient or block‐gradient copolymers. Gradient copolymers with sufficiently sharp gradient profiles can be considered ‘fuzzy’ block copolymers, and they may exhibit self‐organization and nanostructuration both in bulk and in solution. Gradient copolymers can be used potentially in many fields for example, as compatibilizers they help blend immiscible polymers by reducing the interfacial tension of each homopolymer domain, reinforcing agents, damping materials, thermoplastic elastomers, and biocompatible materials. One way of preparing gradient copolymers is by controlled radical polymerization with a reversible addition fragmentation chain transfer (RAFT). Copolymerization conducted under RAFT conditions can generate copolymers with targeted compositions and controlled architectures. Semi‐batch copolymerization, called ‘forced gradient copolymerization’, is employed to tweak the gradient copolymers by continuously introducing one of the comonomers to the polymerization mixture during the reaction, often using syringe pump.