Expanded polystyrene (EPS) is a material that is widely used in energy absorbing applications, especially in helmets, despite its non-renewable origin. Cork and its derivatives, however, are proposed as a substitute for polystyrene foam (EPS) due to their renewable origin and their easy recyclability. In spite of the low-environmental footprint of cork and its derivatives, there is insufficient data on their mechanical behaviour. Consequently, under dynamic and quasi-static loads, four different-density EPS, a natural cork material and five different cork products with different grain sizes and heat treatments were tested. They were compared in terms of their stress–strain and specific stress–strain curve, their volumetric capability to absorb energy, their specific energy, average decelerations and peak deceleration. Finally, EPS foams cannot recover their initial shape upon deformation due to their low resilience capability. This is especially important in applications such as helmets, which are bound to be subjected to multiple impacts. However, cork and its products could have this capability for resilience and would therefore be more suitable for certain applications.

膨胀聚苯乙烯（EPS）是一种材料，尽管其来源不可再生，但仍广泛用于能量吸收应用，尤其是头盔。然而，由于它们的可再生来源和易于回收利用，建议将软木及其衍生物替代聚苯乙烯泡沫（EPS）。尽管软木及其衍生物的环境足迹很小，但有关其机械性能的数据却不足。因此，在动态和准静态负载下，测试了四种不同密度的EPS，一种天然软木材料和五种不同晶粒度和热处理的软木产品。比较了它们的应力-应变曲线和比应力-应变曲线，吸收能量的体积能力，比能量，平均减速度和峰值减速度。最后，EPS泡沫由于其低回弹能力而无法在变形时恢复其初始形状。这在头盔等必定会遭受多次撞击的应用中尤其重要。但是，软木及其产品可能具有这种弹性，因此更适合某些应用。