Optimizing mechanical properties of multi-walled carbon nanotube reinforced thermoplastic polyurethane composites for advanced athletic protective gear

Abstract

This study investigates the mechanical properties of thermoplastic polyurethane (TPU) composites reinforced with multi-walled carbon nanotubes (MWCNTs) for application in athletic protective gear. The objectives were to (1) systematically evaluate the effects of MWCNT loading level and alignment on the tensile, compressive, hardness, and impact properties; (2) identify an optimal MWCNT content range for balanced enhancements; and (3) explore scalable fabrication methods. MWCNT/TPU composites with 0.5-4 wt% loading were prepared by solution mixing and compression molding. Mechanical testing revealed significant improvements, with 62 MPa tensile strength (+19%), 507 MPa modulus (+23%), and 10% higher impact energy absorption achieved at 1-4 wt% MWCNT. MWCNT alignment further enhanced the properties, while loadings above 2 wt% showed some embrittlement. Microstructural characterization evidenced good MWCNT dispersion and interfacial bonding. The results demonstrate that low MWCNT additions can substantially enhance the strength, stiffness, and impact resistance of TPU. This indicates great potential for developing advanced, lightweight athletic protective equipment like helmets and pads with improved energy absorption and durability. Future work will focus on optimizing composite processing and design for specific gear applications.