sviluppo di nuovi bio-nano-compositi a matrice polimerica per sostituti ossei

The recent development in scientific understanding, particularly in the area of material science and biological science, has enabled an impressive progress in attempts to develop new biomaterials. Polymers (HDPE, PTFE, PMMA, etc.) are widely used in biomedical applications, because of their better mouldability, availability, as well as for their low-cost, if compared to metals and ceramics employed in biomedical field. In the last few decades, substantial research efforts were invested to develop bioactive composites as bone analogue replacement by reinforcing bioinert high-density polyethylene (HDPE) matrix with different bioactive molecules. It has been recognized that low elastic modulus (1.5-4.3 GPa) and low strength (17-23 MPa) restrict the use of HDPE composite in major load bearing application, such as bone replacement material (cortical bones: E-modulus ~7-30 GPa and tensile strength ~60- 160 MPa). The above mentioned discussion signifies that polymer-based new functional biomaterials for load bearing hard tissue application (bone, teeth, joint, etc.) are still awaited. For all these reasons, the aim of this proposal is the development of a novel HDPE composite material to be used in load bearing hard tissue applications (bone, teeth, joint, etc.). Chitosan nanofibers and Zirconia (ZrO2) nanoparticles will be used as reinforcement materials for increasing both mechanical properties and osseointegration. The novel fiber reinforced polymer composite materials will exhibit simultaneously high strength together with bioactivity and will provide an alternative choice to overcome many shortcomings of homogenous materials such as metal and ceramic materials.