(Courtesy: Shutterstock/xpixel) People have been using reinforced rubber for nearly a century, but we still don’t know why it’s so strong. Researchers at the University of South Florida (USF) in the US now say they may have the answer thanks to advanced molecular dynamics simulations. Their work could make it possible to design new materials that are safer and have even better mechanical properties. Reinforced rubber is made by adding a nanoparticle filler – typically carbon black or silica – to elastic polymers (elastomers). The presence of this nanofiller explains why tyres, industrial seals and many other everyday rubber products tend to be black in colour. More importantly, the nanofiller makes the material robust to heat and able to withstand millions of cycles of deformation, meaning that objects can last for years, or even decades, without deteriorating. One property that may play a central role in the materials’ mechanical performance is the stickiness of the nanofillers’ surfaces.…