Structural, Mechanical, and Tribological Properties of Oriented Ultra-High Molecular Weight Polyethylene/Graphene Nanoplates/Polyaniline Films

Polymers (Basel). 2023 Feb 2;15(3):758. doi: 10.3390/polym15030758.

Abstract

Preparing high-strength polymeric materials using an orientation drawing process is considered one of the most urgent topics in the modern world. Graphene nanoplates/polyaniline (GNP/PANI) were added to the commercial grade UHMWPE (GUR 4120) matrix as a filler with antifriction properties. The effect of GNP/PANI addition on the structure, the orientation process, the void formation (cavitation), the mechanical, and tribological properties was studied using differential scanning calorimetry (DSC), dynamical mechanical analysis (DMA), and scanning electron microscopy (SEM). The paper's findings indicated an increase in the cavitation effect of 120-320% after the addition of GNP/PANI to the UHMWPE polymer matrix. This increase, during the process of the oriented films' thermal orientation hardening, led, in turn, to a decrease in the tensile strength during the process of the oriented films' thermal orientation hardening. Furthermore, the decrease in the coefficient of friction in the best samples of oriented UHMWPE films was two times greater, and the increase in wear resistance was more than an order of magnitude. This process was part of the orientation hardening process for the UHMWPE films containing PE-wax as an intermolecular lubricant, as well as the presence of GNP/PANI in the material, which have a high resistance to abrasive wear.

Keywords: UHMWPE; cavitation; coefficient of friction; films; graphene nanoplates; lamellar structure; mechanical properties; orientation hardening; polyaniline; polyethylene wax; wear; work of fracture.