Directional Control of the Mechanical Properties of a Resin-Cross-Linking System: A Molecular Dynamics Study

Although thermosetting resins have good physical and chemical stabilities, their deformation ability is limited and fatigue fracture can easily occur. To overcome the defects of thermosetting resins, we propose introducing an aromatic heterocyclic helical macromolecule chain into a thermosetting resin-cross-linked network. The effect of the helical structure on the thermomechanical properties of the thermosetting resin-cured system is quantitatively and qualitatively analyzed using a molecular dynamics method. Results show that the helical structure can affect the mechanical properties of the thermosetting resin-cross-linked system along the pitch direction. The introduction of a helical macromolecule chain reduces the density of the cross-linking points and weakens the heat resistance of the cured system to some extent; however, the influence is insignificant. Nevertheless, we are expected to gain some deep insights into the directional control of the mechanical properties of the resin-curing system and microstructure of the cross-linking network by introducing a helical structure.