Mechanical Properties of Dynamically Vulcanized Thermoplastic Polyurethane (TPU)/Polybutadiene Rubber (BR) Blends

To obtain thermoplastic polyurethane (TPU) with low hardness, dynamically vulcanized TPU/polybutadiene rubber(BR)(70/30) blends were prepared. The effect of dicumyl peroxide (DCP) content and stabilizers on the tensile strength and elongation at break of the dynamically vulcanized blends was examined. The tensile strength and elongation at break of the dynamically vulcanized blends decrease with increasing content of DCP. The addition of optimal content of stabilizer leads to the improvement of tensile strength and elongation at break of the blends. Also, the effect of sulfur cure systems and accelerators on the tensile strength and elongation of the blends was investigated. The tensile strength and elongation at break of all the dynamically vulcanized TPU/BR (70/30) blends using 1-step processing are not higher than those of simple TPU/BR (70/30) blends. However, the tensile strength and elongation of the dynamically vulcanized blends prepared at 8 min (mixing time) using 2-step processing are higher than those of the simple blends.