Amphiphilic Surfactants and Amphiphilic Polymers: Principles of Molecular Assembly

Amphiphilic surfactants and polymers display characteristic molecular self-assembly behavior in solutions, at interfaces and in bulk, generating nanoscale structures of different shapes. These nanoscale features determine many characteristics of these amphiphiles, relevant for their practical applications in materials, pharmaceutical and biomedical technologies. The ability to generate desired nanoscale morphologies by synthesizing novel amphiphiles would allow the amphiphilic systems to be tailored for specific applications. Critical to achieving this goal is an understanding of the link between the molecular structure of the amphiphiles and their self-assembly behavior. In this chapter, we review the principles of self-assembly for both conventional low molecular weight surfactants and amphiphilic block copolymers. The main emphasis is on demonstrating how general principles of thermodynamics and considerations of molecular packing together help predict the self-assembled morphologies given the amphiphile molecular structure. The similarity between the behavior of classical surfactants and amphiphilic block copolymers are identified. The self-assembly behavior of novel amphiphiles can be extrapolated from these fundamental principles.