The main objective of this research is to investigate the use of colloidal Boehmite rods as reinforcement filler for polymer nanocomposites and to introduce them as an alternative to the well-known clay systems. Since Boehmite rods have been studied for many years as a model nematic system, the motivation was to explore some additional properties which could arise from their nematic behaviour in a polymer matrix. The Boehmite system was expected to retain the nematic behavior in the polymer matrix, giving rise to unusual optical properties and a discontinuous mechanical response such that the storage modulus of the matrix polymer would jump to higher values after the isotropic-nematic phase transition. Although such a discontinuity in mechanical properties has not been observed, Boehmite particles have affected dramatically the thermal and mechanical properties as well as the crystal morphology of the polymer system. It has been proven that the Boehmite rods show nematic behavior also in the polymer matrix and increase the storage modulus of the polymer.Applied Science