We have been studying the formation of solid polymer-surfactant films at the air-solution interface formed from cationic surfactants with PEI. We wish to use the highly organised mesostructures formed in these membranes as hosts for the polymerisation of hydrophobic monomers in order to prepare polymer nanostructures which will reinforce our films. Previously polymerisation of monomers in swollen micelles has destroyed the mesophase due to the rapid diffusion of surfactant during the reaction. In our films the high viscosity of the hydrogel may prevent rearrangement of the micelles during the reaction. In this experiment we will begin to identify the best surfactants for encapsulation of styrene and methyl methacrylate within our films and to quantify encapsulation of these species and their location within the films using contrast variation of either the surfactant or monomer species.