Investigation of the mechanical characteristics and thermal behavior of a polymer matrix by addition of different graphene oxide nanosheets: A molecular dynamics simulation

Molecular dynamics simulation (MDS) was applied to examine the effect of graphene oxide nanosheets (GONs) with different edges (armchair and zig-zag edges) on the mechanical behavior (MB) and thermal behavior (TB) of the base polymer matrix (PM). The physical quantities, such as the maximum stress on the samples, stress–strain diagram, ultimate strength (US), Young's modulus (YM), the order parameter (OP), and length changes (LC) were measured for 10 ns. Lennard-Jones (LJ), Tersoff, and Coulomb potentials were used. The PM's maximum stress, US, and YM values were 0.26, 0.22, and 2.23 GPa, respectively. After 10 ns, the OP of PM decreased from 0.79 to 0.52. In studying the PM, the LC was 17 Å when increasing structure temperature to 350 K. The TB and MB of zig-zag nanosheet were higher than for the armchair type. By adding GONs with an atomic ratio of 1% to PM, maximum stress, US, and YM values in structures with armchair nanosheets were 0.34, 0.28, and 2.78 GPa, respectively, and for samples with zig-zag nanosheets were 0.35, 0.30, and 2.96 GPa. After 10 ns, LC increased from 10 to 11 Å for the sample with a zig-zag edge, and from 10 to 12 Å for an armchair edge. This atomic behavior indicated that the atomic structure of Detda and Dgeba matrixes with GONs with a zig-zag edge had higher thermal stability.