The Crashworthiness of Biodegradable Inserts of Sport Helmet

Today, the development of biodegradable polymers has gained significant attention as a promising solution to address the environmental concerns associated with conventional plastics. Biodegradable polymers, also known as biopolymers, are designed to break down naturally over time (maximum of 6 months), reducing their impact on ecosystems and minimizing pollution.<br/>The following article explores the possibility of using dedicated biodegradable composites for injection molding of thin-walled structures used in sports helmets. The paper presents several composites based on a PLA matrix with the addition of other biodegradable plastics such as PBS and PBAT. The article describes the author's production method, which is based on injecting thin-walled structures into an innovative form patented by the authors. The crashworthiness of the energy-absorbing structures obtained this way was then tested using a spring drop hammer. The test conditions replicated the collision of an athlete wearing a helmet with a rigid stationary obstacle. During the test, the dynamic crushing force and displacement were recorded using acceleration sensors and by tracking the position of markers mounted prior to the test on the spring drop hammer tup.<br/>The results are presented as force-displacement crushing curves and images from a high-speed camera. Additionally, the energy absorption of the structures is presented in the form of diagrams. The results were then analyzed, and the two most useful materials were selected in the context of their possible use for the injection molding of thin-walled, energy-absorbing structures used for constructing sports helmets.<br/>The article demonstrates that it is possible to address the environmental challenges and produce energy-absorbing structures made of biodegradable materials that can be successfully used to construct sports helmets of all kinds, replacing the previously used expanded polystyrene. These structures have several advantages. First, users can easily replace them after a crash, restoring 100% of the helmet's protective properties. Second, these structures can be disposed of by composting. Third, the structures provide better protective properties because they utilize a previously unused mechanism of plastic folding instead compression of polystyrene elements