Use of nanoindentation and nanoscratch experiments to reveal the mechanical behavior of sol–gel prepared nanocomposite films on polycarbonate

Sol–gel based UV cured hybrid coatings were prepared by combining different silanes with various urethane acrylate monomers. Effects of precursor concentration and inorganic to organic weight ratio were investigated. Nano indentation, nanoscratch and Taber tests were utilized to assess the behavior of the coatings. It was revealed that lower acrylic silane content and higher inorganic to organic weight ratios improved hardness, elastic modulus and scratch resistance. Increasing inorganic phase increased elastic modulus and hardness. Higher elastic modulus enhanced elastic recovery and scratch resistance of the films. Moderate level of hardness was found to perform better in abrasion resistance.