Mechanical, chemical and acoustic properties of new hybrid ceramic-polymer varnishes for musical instruments

Novel ceramic–polymer hybrid varnishes were designed to protect the wood surface of musical instruments. These hybrid coatings consist of chemically functionalized silica nanoparticles and synthetic solvent-based acrylic- and alkyd–polyurethanes. The nanoparticles were added to increase the abrasion resistance. An alkoxide was used to increase the number and reactivity of OH’s groups on the wood surface improving the adhesion with the coating through a chemical link between them. The properties of the synthetic coatings were compared with those of a traditional varnish (based on alcohol and natural resins) to obtain a better performance. Two types of woods were used: maple and spruce. The samples were characterized by UV–Vis, mechanical and abrasion tests, water’s absorption, acoustic properties, chemical resistance and SEM.