Molecular Dynamics Study of the Photodegradation of Polymeric Chains.

The development of reusable polymeric materials inspires an attempt to combine renewable biomass with upcycling to form a biorenewable closed system. It has been reported that 2,5-furandicarboxylic acid (FDCA) can be recovered for recycling when incorporated as monomers into photodegradable polymeric systems. Here, we conduct density functional theory (DFT) studies with periodic boundary conditions on microscopic structures involved in the photodegradation of polymeric chains incorporating FDCA and 2-nitro-1,3-benzenedimethanol. The photodegradation process of polymeric chains is studied using time-dependent excited-state molecular dynamics (TDESMD) in vacuum and aqueous environments. Changes in the photophysical properties for reaction intermediates are characterized by ground-state observables. The distribution of reaction intermediates and products is obtained from TDESMD trajectories using cheminformatics techniques. Results show that a higher degree of polymeric chain degradation is achieved in the vacuum environment. Additionally, one finds that the FDCA molecule is recoverable in the aqueous environment, in qualitative agreement with experimental findings.