Effect of Epoxidized Natural Rubber as A Compatibilizer in Thermoplastic Polyurethane/Natural Rubber Blends

This study investigates the influence of epoxidized natural rubber (ENR) as a compatibilizer in thermoplastic polyurethane (TPU)/natural rubber (NR) blends, which were prepared through an internal mixer and compression molding. The mixing condition and mechanical properties optimization of the blends were examined following the variation of ENR concentrations. The mixing torque during blending was used to assess the homogeneity degree and processing characteristics based on the incorporation of the ENR. Mechanical properties in terms of tensile properties and impact strength were investigated to elucidate the role of ENR in enhancing the strength of the blends. The modulus and tensile strength increased by adding ENR, reaching an optimal concentration at 3 phr. Also, impact strength confirms the beneficial effects of ENR by exhibiting increased toughness and resistance to impact-induced failure at an appropriate amount of ENR to prevent aggregation when the quantity is excess. These findings highlight the ability of ENR to promote compatibility and enhancing the mechanical properties of TPU/NR blends at 3 phr of ENR loading, offering insights into the development of high-performance elastomeric materials. The presented homogeneous TPU/NR and ENR combination enables the blend for various applications, particularly filament fabrication and 3D printing product development.