# Recovered Foam Impact Absorption Systems
## 1 Introduction
Moreover, PU foam is highly versatile, with different formulations allowing for customization based on specific application requirements, ranging from soft cushioning to more rigid impact protection [18]. This versatility makes polyurethane more adaptable for a broader range of applications compared to other materials, and its widespread use ensures a large amount of waste material available for repurposing [11]. By focusing on polyurethane, this study addresses a significant waste stream while leveraging the material's technical advantages for reuse in protective systems. Table 1 highlights various types of materials previously applied in impact absorption or protective systems, categorized by material type, common applications, and key properties relevant to impact absorption. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Material Type** & **Common Applications** & **Key Properties for Impact Absorption** \\ \hline
**Polyurethane (PU) Foam** & Automotive interiors, packaging, leisure & Lightweight, flexible, excellent energy \\  & facilities, sports equipment & absorption, customizable densities [19] \\ \hline
**Expanded Polystyrene (EPS)** & Helmets, packaging, construction insulation & Rigid, good energy dissipation, low density, \\  & & brittle under repeated impact [20] \\ \hline
**Polyethylene (PE) Foam** & Sports mats, automotive, protective packaging & Lightweight, resilient, durable, excellent \\  & & cushioning, closed-cell structure [21] \\ \hline
**Neoprene Rubber** & Wetsuits, sports equipment, industrial & Elastic, good impact resistance, high durability, \\  & & moisture resistance [22] \\ \hline
**Ethylene Vinyl Acetate (EVA) Foam** & Footwear, sports equipment, protective & Soft, flexible, shock-absorbing, good recovery \\  & & padding & after compression [23] \\ \hline
**Theroplastic Polyurethane (TPU)** & Footwear, mobile device protection, automotive components & Highly elastic, excellent impact resistance, \\  & & good wear and abrasion resistance [24] \\ \hline
**Silicone Rubber** & Medical devices, electronic protection, sports & Flexible, temperature resistant, good shock \\  & & equipment & absorption, durable [25] \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Materials applied in impact absorption or protective systems. The problem arises from the deterioration of foam over time, especially when used in contact with people in leisure facilities, leading to a need for periodic replacement to ensure safety and maintain aesthetic quality. This waste, primarily consisting of spent polyurethane foam, is often disposed of in landfills, contributing to environmental pollution due to the lack of viable recycling options [26]. Given the substantial volumes of PU foam used across multiple sectors, the potential for reusing this material is vast, provided that appropriate methods are developed to recover and repurpose the foam's impact absorption capabilities. The primary objective of this study is to develop a technological application for repurposing spent foam materials and textile elements from leisure facilities into impact absorption systems. This development aims to facilitate the reuse of waste generated within these facilities, thereby reducing global environmental impact by utilizing the materials' inherent technical characteristics and addressing the specific environmental impact of materials such as polyurethane. To achieve this objective, this study will proceed in several phases. First, a knowledge base will be established to understand the impact absorption capacity of foam after its lifecycle in leisure systems. This phase will explore its potential reintegration into impact absorption elements, either as part of broken resistant elements or new protections. Subsequently, the behavior foam for developing new anti-impact systems will be explored. Further phases will focus on enabling the reuse of contaminating elements such as textiles and foam in leisure-related applications, ensuring impact protection and energy absorption to guarantee the safety of the facilities.