A new insight into the influence of atomic motion on the mechanical properties of polyethylene chains

Abstract

To investigate the potential mechanism affecting the mechanical properties of polyethylene (PE) are beneficial to its practical application. In this paper, the atomic motion is decomposed to reveal the underlying mechanisms of how PE mechanical properties are affected by temperature, strain rate, and inter-chain interaction, using molecular dynamics (MD) simulations. It is found that the underlying mechanism of temperature affecting mechanical properties of PE chains is further demonstrated to closely relate with the radial motion of PE atoms. The increasing motion range of PE atoms in the radial direction would result in a decrease of breaking stress and breaking strain of PE chains in the axial direction. In addition, the strain rates would suppress the radial movement range of the PE atoms, which strengthens the mechanical properties of the PE chain. In contrast, the introduction of interaction between PE chains by increasing the chain number causes the radial motion of atoms to be more intense, which reduces the strength of the polyethylene chains. These simulation results are highly expected to provide novel insight to understand the mechanism of materials' mechanical properties.