Role of interfacial adhesion and fiber length on the mechanical performance fiber reinforced thermoplastic elastomers

Abstract Thermoplastic elastomers combine inherent benefits such as the processability and recyclability of thermoplastics and the elasticity, toughness, and flexibility of elastomers. In this work, polyester based thermoplastic elastomers have been reinforced with carbon and poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers of similar strength and stiffness. Testing of the respective mechanical properties revealed that the PBO reinforced composites yielded higher tensile strength. Single fiber pullout testing was also performed to evaluate the respective interfacial and mechanical properties where it was found that the apparent interfacial shear strength for carbon fibers was two to three times greater than their PBO counterparts. Further analysis revealed that the fiber length of the PBO composites was much greater than for carbon fiber, resulting in superior strength of the PBO reinforced elastomers.