Examining Tribological and Mechanical Properties of PLA/TPU Blends for Footwear Applications

The current study focusses on examining the tribological behavior of polymer blends fabricated using a single screw extruder followed by fused deposition modeling techniques. For polymer blending, the loading of polymers such as polylactic acid (PLA) and thermoplastic polyurethane (TPU) was varied in the ranges of 30%, 50%, 70%, and 100%. All these samples underwent a dry sliding wear test, with velocities ranging from 0.5 to 1.5 m/s. The applied load was consistently maintained at 200 N, and a sliding distance of 2000 m was used. Results reported that the coefficient of friction (COF) of pure PLA and TPU samples increased with an increase in velocity. Concerning polymer blending, the 50:50 and 30:70 (PLA/TPU) loaded samples exhibited lesser COF values with increasing velocities. Specifically, the 50:50 loaded samples showed COF values of 0.609, 0.439, and 0.381 at 0.5 m/s, 1 m/s, and 1.5 m/s, respectively. In the case of 30:70 loaded samples, the COF values were 0.292, 0.186, and 0.136 at 0.5 m/s, 1 m/s, and 1.5 m/s, respectively. Regarding the mechanical properties, the 70:30 (PLA/TPU) samples exhibited improved properties in tensile, flexural, and compressive properties. For instance, the tensile, flexural, and compressive strength values were 42.53 MPa, 61.85 MPa, and 46.12 MPa, respectively.