This work is concerned with the material characterisation and the phenomenological modelling of acrylic bone cement during polymerisation as well as with the implementation of the model into a numerical CFD-code in order to apply it to the specific issues of vertebroplasty. Based on the study of the reaction kinetics the thermodynamic properties of acrylic bone cement are analysed with respect to their dependence on temperature and the progress of polymerisation. The mechanical behaviour is significantly influenced by two processes, on the one hand by the dissolution of the two mixing components of acrylic cement, the polymer powder and the liquid monomer, and on the other hand by the radical polymerisation. Thereby the decisive influence of both processes on the mechanical behaviour can be considered chronologically separated. The experimental investigations provide a basis for developing a thermomechanical-chemically coupled material model which can describe the observed thermodynamic and mechanical behaviour, like heat release and shrinkage in volume by means of suitable evolution equations for the dissolution and polymerisation. In addition, appropriate functionals and a power law allow the model to represent the viscoelastic and shear-thinning characteristics. The thermodynamic consistency of the material model is provided by deriving the constitutive material equations in consideration of the second law of thermodynamics. Moreover, the parameters of the material model are determined on the basis of the obtained experimental data by linearising the material equations and applying established numerical methods. The model is implemented into a CFD-Code for two-phase flow which offers the possibility to include the geometrical and physical boundary conditions of a porous bone structure of a vertebral body as it is typical for the clinical application of vertebroplasty. Concluding example simulations as well as a comparison of an experimental and a numerical identically depicted injection process of acrylic bone cement into a porous structure prove the capabilities and the performance of the presented approach.
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