WHATS NEW IN RHEOMETRY AND VULCAMETRY OF RUBBER MATERIALS

This paper discuses current methods for the assessment of theological and curing properties of rubber materials, i.e. raw gum and filled com pounds, with respect to now established aspects of rubber science. By considering how a basic property like the (shear) modulus is likely to evolve along the operations, it is shown that rubber processing can b e considered as a journey on a tridimensional map Modulus - Temperatur e Process stage. With this approach, the scopes of rheometry and vulca metry are clearly identified. The limits and difficulties in assessing the theological properties of rubber materials are seen when consider ing how the viscosity function varies with filler content. This leads to the important observation that rubber compounds cannot readily be t ested in linear viscoelastic conditions. Basic principles of testing m ethods are then considered with respect to peculiar properties of rubb er materials and a few recent novelties in commercial instrumentation are reviewed.