Experimental study and numerical simulation of the vertical bounce of a polymer ball over a wide temperature range

The dependence to temperature of the rebound of a solid polymer ball on a rigid slab is investigated. An acrylate polymer ball is brought to a wide range of temperatures, covering its glass to rubbery transition, and let fall on a granite slab while the coefficient of restitution, duration of contact, and force history are measured experimentally. The ball fabrication is controlled in the lab, allowing the mechanical characterization of the material by classic dynamic mechanical analysis. Finite element simulations of the rebound at various temperatures are run, considering the material as viscoelastic and as satisfying a WLF equation for its time-temperature superposition property. A comparison between the experiments and the simulations shows the strong link between viscoelasticity and time-temperature superposition properties of the material and the bounce characteristics of the ball.