An Application of MALDI-MS and Reactive Molecular Dynamics in Determining the Mechanisms of Char-Formation During the Thermal and Oxidative Degradation of Polymers
Marc R. Nyden, William E. Wallace, W H. Awad
The mechanisms by which polymers form carbonaceous chars as a result of thermal and oxidative degradation is an interesting scientific problem, which has important commercial (formation of carbon fibers and nanostructures) and public safety implications (materials flammability). In general, chars are thought to form from reactions involving polyene precursors, which in turn are produced by the abstraction and elimination of hydrogen atoms and functional groups from the polymer backbone. Many of these intermediates are amenable to standard metal cationization treatments and can, therefore, be monitored by MALDI-MS.In previous papers,1,2 we have reported progress in using Reactive Molecular Dynamics (RMD) to model the thermal decomposition chemistries of polymers. In this technique, a reactive force field, which accounts for the dissociation and formation of covalent bonds is employed in conjunction with standard methods for solving the classical equations of motion. It is computationally efficient compared to electronic structure calculations and, therefore, can be used to simulate chemical reactions in large molecular systems while still accounting for the effects of inter-molecular interactions in condensed phases. In this talk, we will report progress in using our RMD code (MD_REACT) in conjunction with MALDI-MS and FTIR analyses of pyrolysis residues to investigate mechanisms of char formation in vinyl polymers.
, Wallace, W.
and Awad, W.
An Application of MALDI-MS and Reactive Molecular Dynamics in Determining the Mechanisms of Char-Formation During the Thermal and Oxidative Degradation of Polymers, PMSE Preprints of the American Chemical Society, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=861195
(Accessed February 29, 2024)