Atomistic molecular dynamics simulations of the tensile strength properties of polymer-calcite systems

Abstract

The production of solids can occur in poorly consolidated carbonate rock reservoirs, leading to equipment damage and environmental waste. This issue can be mitigated by injecting formation-strengthening chemicals, and the performance of these chemicals can be assessed in terms of their tensile strength and interfacial interaction with calcite, the main component of carbonate formations. This study aims to investigate the tensile deformation behaviour of polymer-calcite systems. Classical atomistic molecular dynamics (MD) simulations are utilised to model the interaction of polyacrylamide-based polymer additives, including pure polyacrylamide (PAM), hydrolysed polyacrylamide (HPAM), and sulfonated polyacrylamide (SPAM) with a calcite (1 0 4) structure. Uniaxial tensile simulations demonstrate that the interfacial strength of the polymer-calcite system is significantly stronger than the corresponding bulk polymer strength, resulting in strong polymer adhesion at the calcite surface during deformation. HPAM exhibits high bulk polymer and interfacial strength, presumably due to the presence of the acrylate monomer in ionised form, making it an excellent formation-strengthening agent.