The influence of nanohydroxyapatite on selected properties of polyurethane-based bone scaffold

Polyurethanes (PUs) are defined as a big group of synthetic polymers that contain repeated urethane linkage in the backbone. The obtained polymer can differ in shape and properties, depending on the components and the synthesis process. That is why PUs are widely used in a big range of applications. Due to their good biocompatibility, it is possible to manufacture polyurethane-based biomaterials as well. Another big advantage of polyurethanes is the ease of modification, using many types of fillers.

One of the most commonly used fillers in biomedical applications is hydroxyapatite (HAp), a calcium phosphate mineral. HAp-like compounds build around 65% of a bone, therefore HAp is a good alternative for a synthetic bone modifier. PU-based materials with an addition of HAp can exhibit not only enhanced osteogenesis but also improved mechanical properties such as tensile strength and Young modulus.

In this work, polyurethane-based bone scaffolds manufactured in the two-step bulk polyaddition process were presented. The influence of various HAp content was investigated. The chemical structure of the samples was checked using spectroscopy (FTIR). Mechanical properties were evaluated by a compression test. Bioactivity of the material was investigated based on SEM images before and after incubation in SBF solution.