Abstract

Elastomeric composite materials are widely used in multiple applications, especially in the automotive industry; however, they have the drawback of being difficult to recycle, generating a significant environmental impact. For this reason, in recent years there has been an increase in research for the development of self-healing and biodegradable materials that minimize this impact by extending their lifetime. In this context, the aim of this work is to design a new generation of self-healing elastomeric composite materials using additives of natural origin. For this, epoxidized natural rubber (ENR) and cellulose propionate (CP) were used as matrix, reinforced with cellulose fibers. Self-healing was achieved by combining the flow of the thermoplastic (CP) phase (extrinsic mechanism) and the formation of hydrogen bonds between the ENR and the CP (intrinsic mechanism). A promising repair efficiency of 95% was obtained, as well as an increase in tensile strength in the presence of cellulose fibers, without affecting the healing capacity of the material. Therefore, this work overcomes the well-known dichotomy between mechanical performance and self-healing and constitutes a new contribution in the field of self-healing elastomeric composites using bio-based additives.

Abstract

This work presents ionically vulcanized carboxylated nitrile rubber (XNBR) compounds reinforced with conventional and sustainable fillers. The impact of adding traditional fillers, such as carbon black and silica, as well as sustainable options, such as cellulose and ground tire rubber from end-of-life tires (GTR), on the rubber's mechanical, thermal, self-healing, and recyclability properties is carefully analyzed. The results demonstrate that the incorporation of sustainable fillers achieves a favorable balance between repairability, recyclability, and mechanical performance. In particular, the compound with GTR exhibits reinforcement levels comparable to those of silica-based compounds, while maintaining full reprocessing and repairability. This study highlights the potential of using sustainable and recycled materials in the rubber industry, significantly contributing to the development of environmentally friendly elastomeric compounds.