In this thesis, zinc oxide nanoparticles () were used for the preparation of polycaprolactone (PCL)?based nanocomposites (NCs), by solvent casting and ultrasonic-assisted method. In the first step, the NP surfaces were modified with biosafe molecules like poly(vinyl alcohol), citric acid and vitamin B 1 . The non?covalent interactions of the with the organic molecules were responsible for their successful modifications. The after the modifications displayed uniform size distributions and better dispersion in the organic solvent. According the thermogravimetric analysis of the modified , 80-90 wt% of the organic molecule were loaded on the ZnO NP surfaces. The functionalized ZnO with different weight percentages (2, 4 and 6 wt%) were exploited as nanofillers for fabrication of PCL-based NC films, under ultrasonic method. The fabricated films showed enhanced mechanical strength, ultraviolet-visible absorption and wettability, compared to the pure PCL. Transition electron microscopic images of the NCs verified their steady dispersion and no sign of agglomerations in the matrix. In-vitro bioactivity test of the NCs by immersing them in the simulated body fluid solution showed that the ZnO incorporation can drastically increase the hydroxy apatite growth on the films and decrease the solution pH, because of the solution hydroxyl waster for the hydroxyl apatite formation. Between all the nanocomposites, PCL/ZnO-VB1 NCs showed the highest bioactivity and dispersion in organic media. By thermogravimetric analysis of the NCs, it was noticed that the can promote the thermal degradation of the NCs, therefore the thermal stability of the nanocomposites is decreased.
