Increasing production rates of rubber products combined with a lack of effective recycling methods have led to an exponential growth of rubber waste in landfills and incineration, inducing severe environmental problems. Due to the crosslinking of rubbers, recycling via melt processing cannot be used to process emerging rubber waste. One way to recycle cross-linked rubber is the mechanical recycling into rubber particles (ground vulcanized tire rubber waste, GTR). This elastic filler can be used to produce thermoplastic elastomers (TPE). These composites are prepared by melt mixing of a thermoplastic polymer and GTR particles. The mechanical properties of GTR particle filled thermoplastics decrease proportionally to the percentage of recycled GTR particles due to low interfacial adhesion between the composite components. Recent studies have shown, that surface activation as well as the application of gamma ray-induced interfacial crosslinking did not enable the multiple recycling of GTR based TPE while improving its comparably low mechanical properties. Hence, innovative methods are crucially needed to enable and strengthen circular economy. A promising way is the application of electron beam treatment to produce recyclable TPE based on recycled polyethylene and/or polypropylene as well as GTR particles.

In this study, life cycle analysis was done to compare the environmental impacts of the cascade of mechanical recycling of rubber and mixed polyolefin waste on the one hand, and the conventional production of virgin rubber and polyolefin on the other hand. Under application of the LCA software Umberto, real industry data was combined with environmental database information. The results of this study will contribute to the understanding of current and future recycling processes and will help guide future research towards innovative solutions of the global plastic waste problem.