| Interpenetrating networks consist of two or more networks of different components which are entangled on a molecular scale and cannot be separated without breaking at least one of the networks. They are of great technological interest because they allow the blending of two or more otherwise incompatible properties or functions, and furthermore synergistic effects might arise from the simultaneous operation of the two networks. So far, the preparation of interpenetrating network gels by self-assembly approaches was doomed to fail because the conventional polymers and surfactant building blocks either phase separate or form mixed assemblies, respectively. In this project we will overcome this barrier by making use of the orthogonal self-assembly of low molecular weight (LMW) gelators together with surfactants, to allow for the preparation of interpenetrating networks completely by self-assembly (for a first example see A. Brizard, J. van Esch et al, Angew. Chem., 2008, 47, 2063). These so-called self-assembling interpenetrating networks (SAIN?s) are yet unexplored but are expected to have a number of intriguing properties. For instance, the presence of two coexisting networks will immediately offer new possibilities for compartmentalization, and will allow one to adjust the viscoelastic properties between ?soft? and ?hard? gels. The non-covalent character of SAIN?s makes their formation fully reversible, which can be exploited for dual responsive systems. Most interestingly, SAIN?s can also act as a very primitive, yet unique model for biological interpenetrating networks like the extracellular matrix and the cytoskeleton, and thereby contribute to our understanding of these very complex systems. It is the aim of this project to open up and explore the fascinating field of SAIN?s. The first objective is to investigate the scope of SAIN?s and unravel the selection rules for orthogonal self-assembly of LMW gelator systems and/or surfactants. The second objective is to explore the viscoelastic properties of SAIN?s in relation to its morphology and dynamic self-assembly behavior. With this respect, we aim to understand and utilize the changes in morphology and viscoelastic properties that will be induced by changes in the interactions between the two kinds of networks. |
