Making and assembling materials in surfactant hexagonal phases

I will describe our recent work on polymerization and assembly of particles in surfactant hexagonal mesophases. We have demonstrated that synthesis of condensation polymers in a hexagonal mesophase results in the formation of rod-like colloidal objects.  As the monomer polymerizes, it swells the hexagonal phase, and as the molecular weight increases, it phase separates. This phase separated object is assembled into a rhombohedral object and finally into a rod-like object by matrix mediated interactions.  I will also discuss assembly of particles in the hexagonal mesophase.  We show that the size of the nanoparticulate inclusion, d, in a surfactant mesophase characterized by size, a, determines particle organization in the mesophase. Small particles, viz. d < a, are templated by the mesophase, while for d ~ a, there is a coexistence between a dispersed particle phase and string like particle aggregates. For d > a, the particles organize into networks of string-like aggregates. This behaviour is generic, independent of the particle surface chemistry. We show the formation of networks of inorganic oxides, metals, proteins and polymer hydrogels in hexagonal mesophases.  I will describe our use of this strategy to generate free standing, macroporous materials.