Soft materials, constituted by molecules that are held together by weak inter-macromolecular forces, are characterized by complex structures and phase behaviour. Colloidal suspensions and emulsions such as milk and paint, polymeric and biological materials, foam, and liquid crystals are some common examples. The size of the molecules that constitute these materials is typically between a few nanometers and a few micrometers. In contrast to atomic systems whose relaxation times are of the order of picoseconds, soft materials relax on time scales that usually lie between 10-8 and 103 seconds. The structure and dynamics of these materials can therefore be easily studied using relatively simple laboratory techniques. Characterized by elastic constants that are many decades lower than those of traditional atomic solids, soft materials are viscoelastic and can be used in the study of a variety of non-equilibrium phenomena. Inter-constituent interactions can be easily modified in soft materials; a feature that is particularly suitable for engineering new materials with interesting and useful properties. Their structural complexity and mechanical flexibility make soft materials ideal for many applications. Moreover, soft matter systems are a testing ground for theories and models of statistical physics.
The soft condensed matter group at RRI is engaged in research on liquid crystals and their chemical synthesis, colloids, polymers, nano-composites, amphiphilic systems, physics and chemistry of surfaces, and biological physics.