The objective of the Research Unit is to gain a multiscale understanding of fracture processes in reinforced elastomeric blends supported by different modelling approaches which operate on the statistical-mechanical, mesoscopic and continuum mechanical levels. Besides the establishment of durability predictions applicable in Finite Element Analysis, fundamental material specific problems, e.g. the influence of pre-deformation, strain-induced anisotropy and fractal nature of reinforcement on crack propagation behaviour, should be investigated.
Technical elastomers are highly filled, cross-linked and topologically entangled polymeric blends. Due to their adjustable elastic and viscous properties, these systems are widely used in industry and technology, for example in tires, drive systems and print rollers. Dynamical operation conditions put extremely high demands on performance and stability of these materials. The required service life is usually decreased due to material damage as a result of wear processes such as abrasion and wear fatigue, mostly caused by crack formation and propagation.
The scientific importance of this fundamentally oriented project is due to a novel combination of experimental methods of fracture mechanical characterization and new modelling techniques with a special focus on the multiscale structural features of reinforced elastomeric blends.
The project covers structural aspects of filled heterogeneous polymer networks within the range from nanometres to millimetres and connects these aspects with the constitutive properties of elastomers. The objective is to obtain reliable lifetime and durability predictions based on new fracture mechanical and material-theoretical methods implemented in finite element simulations. The use of this theoretical-numerical approach allows a realistic description of complex geometrical and loading conditions where the peculiarities of the mechanical behaviour of elastomeric materials are included. So, large deformations, non-linear elasticity with softening effects, velocity and frequency dependent as well as frequency independent dissipative properties should be taken into account.
The multiscale research concept represents an ambitious interdisciplinary challenge at the interface between the engineering and natural sciences, especially physics. Convergence is expected by considering problems from two points of view: using the phenomenological approach on the macroscopic scale and the structural approach on the microscopic or nanoscopic scale.
Various exemplary elastomeric blends modified with nanoscale fillers such as carbon black, precipated silica as well as an organic nanodisperse layered silica are considered within the research unit. Such materials become more and more important in elastomeric compounds used in industrial applications. To understand the specific aspects of elastomeric nanocomposites, a special emphasis is placed on the interface topic.
The constellation of the scientists involved in the project favours a comprehensive treatment of the topic, i.e. the development of basics and strategies for the transfer onto technical applications, with engineering as well as scientific, in particular physical methods.
Deutsches Institut für
für Polymerforschung Mainz
Institut für allgemeinen Maschinenbau
Institut für Statik und
Dynamik der Tragwerke