POLYMER GELS WITH A MICRON-SIZED, LAYER-LIKE ARCHITECTURE BY POLYMERIZATION IN LYOTROPIC COCOGEM PHASES

Polymerization of hydrophilic monomers, such as acrylamide, in the aqu eous lyotropic phases of counterion-coupled gemini surfactants (''coco gems'') results in highly ordered gels with a layerlike architecture b etween the submicrometer and micrometer length scale. The order of suc h gels is preserved even after removing the templating surfactant. The evolution of the gels is monitored using polarized light optical micr oscopy, rheology, small-angle X-ray scattering, and scanning electron microscopy (SEM). The synthesis envokes structural changes of the temp lating lyotropic phase structure as well as demixing of the gelling po lymer and the surfactant phase. The overall gel morphology is, however , still controlled by the anisotropy of the surfactant assembly. Hence , the polymer gel is not a direct cast of the original phase structure , but its growth is indirectly controlled by the ordered arrays. The p ersistence of the lyotropic liquid crystalline phases of cocogems is h igh enough to preserve a layered order, however with the characteristi c size of a demixing structure rather than that of the parental lyotro pic phase. Chemical functionalization of these gels is easily achieved by copolymerizing functional comonomers, such as acrylic acid or dime thylaminoethyl methacrylate. It is expected that these ordered gels, s imple to prepare and inexpensive, will find a number of applications i n various fields of modern materials science, such as for the construc tion of size-selective membranes or high-performance material hybrides .