15 Self-Assembled systems

Abstract

This chapter shows how quantitative predictions of the self-assembly behavior can be made, given the molecular structure of the surfactant and the solution conditions. In this chapter, the general principles of self-assembly are discussed without invoking any specific models for the Gibbs energy of aggregation. The chapter summarizes the molecular packing considerations important to the formation of aggregates. The theory of aggregation in aqueous solutions is presented in the chapter. It constitutes the point of departure for all theoretical developments described in the other sections of this chapter. The self-assembly of nonionic surfactants with oligomeric head groups is treated here, the theory of aggregation is extended to binary mixtures of surfactants. The self-assembly of surfactants in non-polar solvents forming reverse micelles is treated next. The aggregation behavior of surfactant molecules in polar organic solvents and in binary mixtures of water and polar organic solvents is examined. A theory of solubilization in aqueous surfactant micelles is formulated in the chapter for hydrocarbons and hydrocarbon mixtures. The chapter develops a thermodynamic treatment of droplet and bicontinuous microemulsions and explicit expressions for the microemulsion characteristics and for the calculation of the interfacial tensions.