Thermal‐oxidative aging and tribological properties of carbon nanotube/nitrile butadiene rubber composites with varying acrylonitrile content: Molecular dynamics simulations

Abstract

Nitrile butadiene rubber (NBR), a common material used in the stator rubber of screw pumps, usually undergoes severe thermal‐oxidative aging and wear at various temperatures and pressures. In this study, 1,2‐dihydro‐2,2,4‐trimethylquinoline (antioxidant RD) and carbon nanotubes (CNTs) were introduced into NBR to improve its thermal‐oxidative aging performance and reduce its wear. The thermal‐oxidative aging and mechanical and tribological properties of NBR composites with acrylonitrile (ACN) contents of 28%, 33%, and 41% were investigated via molecular dynamics simulations, and the interaction mechanisms of four composites: RD/N28, CNT/RD/N28, CNT/RD/N33, and CNT/RD/N41, were investigated at the atomic level. A three‐layer model (Fe–Composites–Fe) was developed to simulate the wear process of the composites. CNT/RD/N41 exhibited better thermal‐oxidative aging and tribological properties than those exhibited by CNT/RD/N28 and CNT/RD/N33. This was attributed to an increase in the polar–polar interactions of the nitrile (CN) groups with an increasing ACN content. During friction, a larger frictional force existed between the CNT/RD/N41 molecules, which effectively maintained the stability of the matrix. This study provides a scientific reference for the preparation of high‐performance NBR at the microscopic scale, which may extend the service life of screw pumps.

Molecular Dynamics Simulation on Polymer Tribology: A Review

“…Chen et al calculated the bulk, shear, and Young's modulus of carbon nanotube (CNT)/ nitrile butadiene rubber (NBR) composites by the constant-strain method (Figure 1). The results indicated that the increase in acrylonitrile content improved the mechanical properties of the composite at constant CNT content, which is attributed to the polar interactions between the -CN groups [42]. Similarly, the elastic modulus of polymer/polymer composites such as Eucommia ulmoides gum (EUG)/natural rubber (NR), polyamide 66 (PA66)/graphene (GE), and polyimide (PI)/lanthana can be calculated with the assistance of MD simulation [43][44][45].…”

“…properties of the composite at constant CNT content, which is attributed to the polar in teractions between the -CN groups [42]. Similarly, the elastic modulus of polymer/poly mer composites such as Eucommia ulmoides gum (EUG)/natural rubber (NR), polyamide 66 (PA66)/graphene (GE), and polyimide (PI)/lanthana can be calculated with the assis tance of MD simulation [43][44][45].…”

Molecular dynamics simulation of epoxy resin modified by polyimide grafted graphene oxide

“…20 With the development of theoretical calculations, molecular dynamics (MD) simulation provides a new way to study the prediction of material properties and modification mechanisms, which can explore the properties of materials at the molecular level, while saving time. [21][22][23] Jang et al 24 explored the elastic and plastic properties of epoxy resin through MD simulations, revealing the deformation-to-failure mechanism of epoxy resin. Taking inspiration from the successful utilization of MD simulations in exploring material properties, our goal is to use this methodology to explore and predict the impact of physically blending PI with GNS and grafting PI onto GO on the performance of epoxy resin.…”

Polydopamine in‐situ polymerized on graphene oxide for nitrile butadiene rubber with high strength, elasticity and aging resistance

“…It is a promising channel to prepare the high‐performance rubber composites by nanofiller, such as nano marble, 12 nano silica, graphene, hydrotalcite, carbon nanotubes, zirconium phosphate and so on 13–15 . These nanofillers with excellent properties can make outstanding contributions to certain aspects of rubber properties such as mechanical properties, 16,17 thermal stability 18,19 and aging resistance 20 . However, in general, the elasticity of rubber will be greatly reduced after adding with the reinforced nanofillers 21,22 .…”