INTRODUCTION TO SOFT MATTER SYSTEMS

The overwhelming part of what is currently considered as soft condensed matter systems consists of organic molecules and sometimes water. Systems range from polymer melts to biomolecules in aqueous solution, they comprise complex fluids like microemulsions, membranes and vesicles, aggregating and non-aggregating polymers in solutions and melts etc. The main elements present in the constituents are H, C, N, O yielding often only poor X-ray contrast. Therfore neutrons turn out to be a unique probe for which contrast is readily at the disposition by H/D replacement. In addition motions on a molecular level are accessible by inelastic neutron spectroscopy. First some general principles are explained which are illustrated by the results of neutron investigation on block-copolymer aggregates in solution and the dynamics of long polymer chains in a melt.