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This paper studies the competition between electric and mechanical force fields simultaneously applied to a polar elastomer that can lead to electric breakdown. The analysis of the system, performed assuming that the free energy of the elastomer is simply the addition of polarizing and stretching energies leads to the classical “thermodynamic” (in this case “electromechanical”) stability.

Understanding the thermal behaviour of lignin is crucial in order to realise its valorisation as an engineering polymer.

Artificial turf is increasingly being used in the construction of football pitches. One of its characteristics is an infill of sand and rubber granules. At present, different materials and layer thicknesses, as well as grain sizes are used for the sand and mainly for the rubber, but they are chosen with little scientific evidence about their influence on the mechanical and biomechanical properties of the pitch. Based on knowledge from materials science, it is reasonable to suggest that grain morphology may have a large influence on pitch performance. This paper presents research conducted to assess the influence of different parameters related to infill grain morphology on the mechanical properties of artificial turf (force reduction (%), vertical deformation (mm) and vertical ball bounce (m)), as well as on their wear with use, measured according to the F ed eration Internationale de Football Association (FIFA) procedures. The results show a significant reduction of pitch performance with use and a significant influence of grain morphology in mechanical response of artificial turf with respect to impact forces and ball rebound.