Mikromechanisch motivierte Modelle zur Beschreibung finiter Deformationen gummiartiger Polymere Physikalische Modellbildung und numerische Simulation

The thesis proposes a new micromechanical-based model for the description of elastic and viscoelastic behaviour of rubber-like polymers at large strains. In the first part classic models of elasticity of single polymer chains are compared within a consistent model frame of statistical mechanics. Furthermore a micromechanical-based model of single polymer chains is proposed which explains the viscoelastic behaviour by entangling and disentangling processes of single chains during deformation. The new model of viscoelasticity of single polymer chains is one of the crucial points of the thesis. The second part treats the macroscopic modelling of a rubberlike polymer as a three-dimensional interacting network of chains. The developed one-dimensional models of single chains are used further on by using a new directly evaluated micro-to-macro-transition in a discrete direction space. For the description of three-dimensional viscoelasticity of rubber materials no tensorial but only scalar internal variables are used what relieves the numerical implementation substantially. The used scalar internal variables are associated with the viscous deformation on a sphere. The new directly evaluated micro-to-macro-transition in a discrete direction space forms the second crucial point of the proposed material model of viscoelasticity of rubberlike polymers. In the last part of the thesis the efficiency of the new material model is demonstrated by a comparison between experimental data and numerical simulation. (orig.)SIGLEAvailable from TIB Hannover: RR 7199(9) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman