The effects of urea and caprolactam on the molecular mechanisms and elastic modulus of polyvinyl alcohol (PVA): A molecular dynamics simulation study

The interaction mechanism in modified poly(vinyl alcohol) (PVA) with urea and caprolactam were investigated by molecular dynamics (MD) simulation method. Five simulation models of PVA composites with different plasticizer content were constructed to investigate the variation of the intermolecular interaction as well as its effect on the elastic modulus of PVA. The results indicated the interaction between polar functional groups and surrounding hydrogen atoms in PVA was hydrogen bonds. With the increasing of urea and caprolactam contents in PVA system, the elastic modulus of the specimens decreased due to the comparable weak intermolecular and intramolecular interaction, although the modified PVA showed good compatibility with the compounding urea and caprolactam.