Molecular dynamics simulations of solvent evaporation-induced repolymerization of covalent adaptable networks

YG Sun and H Yang and YF Guo, COMPUTATIONAL MATERIALS SCIENCE, 192, 110412 (2021).

DOI: 10.1016/j.commatsci.2021.110412

Covalent adaptable networks (CANs) can be decomposed in suitable solvents via bond exchange reactions. Repolymerization can occur by heating the decomposed solution and evaporating the solvent. This solventassisted decomposition and repolymerization approach can be used to recycle CANs. In this study, the solvent evaporation from decomposed CAN solutions along with the repolymerization of decomposed chain segments are investigated using molecular dynamics simulations. The evolution of density profiles and chain segment lengths are presented to characterize the solvent evaporation and network repolymerization. The effects of solvent molecule size and evaporation rate on the evaporation and repolymerization processes are analyzed. Our results show that a polymer-rich layer at the solution surface quickly forms when evaporating into a vacuum. The polymer-rich layer significantly inhibits the evaporation of solvent molecules with larger size. Molecules have sufficient time to diffuse when evaporating at a slow rate, thus a more homogenous density distribution can be achieved.

Return to Publications page