Organic-Inorganic Films with Anticorrosive and Bactericidal Properties for Titanium Implants

This study seeks to synthesize, by the sol-gel method, an organic-inorganic hybrid coating of polyurethane, siloxane and silver nanoparticles to cover titanium prostheses, aiming to act as an anticorrosive protection barrier, inhibiting the release of metallic ions in the human body. In this context, a hybrid based on the TEOS (tetraethyl orthosilicate) alkoxide precursor was used to carry out the acid hydrolysis/condensation process. Then, silver nanoparticles were added, and the mixture was done with the incorporation of polycaprolactone diol, followed by the addition of hexamethylene diisocyanate, to form polyurethane. The hybrid coatings were applied on titanium plates, and morphological, physical-chemical and electrochemical characterizations were carried out, as well as the evaluation of bactericidal and antifungal activity, in order to evaluate the performance of the coatings and the influence of diferente concentrations of silver nanoparticles (10 mL, 20 mL and 40 mL). The results showed that although Híbrido 10 (lowest concentration of silver nanoparticles, 10 mL) presented the best morphological characteristic without cracks and with satisfactory roughness to obtain the best bacterial behavior, the Híbrido 20 sample presented the best electrochemical performance.

Keywords:
Polyurethane; Silver nanoparticle; Coating; Sol-gel; Titanium prostheses; Corrosion