The combined use of two or more materials in one composite part is nowadays necessary for the product development of polymer parts in order to get an integration of function and design. Furthermore, a growing cost pressure enforces a reduction of production steps, e.g. realized by multi-component injection moulding. Especially the automotive engineering turns his attention for the integration of sealing and damping functions as well as for weight reduction to composite parts made of a hard thermoplastic and a soft rubber material. To ensure an everlasting operation of such composite parts, a strong adhesion between these components is necessary. This thesis deals precisely with the direct material bonding of thermoplastics and peroxide cross-linked rubbers. Using the combination PA6.6 and HNBR, the influence of rubber compound ingredients and process parameters on the adhesion strength is determined and evaluated based on analytical results. Additionally, by using basic rubber compounds and simplifying boundary conditions conclusions on the bonding mechanisms can be drawn.