Abrasion resistance of acrylic polyurethane coatings reinforced by nano-silica.

Graphical abstract Highlights • Abrasion resistance of polyurethane clearcoats is significantly enhanced by nano-silica additives. • Scratch, abrasion, SEM & TEM results are presented. • The effect of different weight fractions and applied abrasion forces is evaluated. • Abrasion resistance improvement is discussed using wear mechanisms. • Much more economical coatings can be fabricated using precipitated type of nano-silica reinforcement. Abstract Nano-particulate reinforced polymer composites are recently being used in many laboratory and industrial applications such as automotive manufacturing industries. However, still further studies are demanded to enhance tribological and mechanical properties leading to achieve as the best resilience as possible required for severe loading or harsh environmental conditions. The purpose of the current paper is studying the scratch and abrasion resistance of the acrylic-based polyurethane nano-particulate clearcoats reinforced by the two types of fumed and precipitated nano-silica reinforcements. To do this, scanning electron microscope (SEM), transmission electron microscope (TEM), scratch and pin-on-disc abrasion resistance experiments were carried out. It was found that the nano-silica additives considerably enhance tribological and mechanical properties of the examined coatings. It was also found that the precipitated type of nano-silica clearcoat is hard enough, tough, and very resistant against wear and environmental conditions and therefore can be considered instead of the too expensive fumed type of nano-silica. [ABSTRACT FROM AUTHOR]