Abstract
The thermal decomposition of polyphenolic resins was studied by reactive molecular dynamics (RMD) simulation at elevated temperatures. Atomistic models of the polyphenolic resins to be used in the RMD were constructed using an automatic method which calls routines from the software package Materials Studio. In order to validate the models, simulated densities and heat capacities were compared with experimental values. The most suitable combination of force field and thermostat for this system was the Forcite force field with the Nosé–Hoover thermostat, which gave values of heat capacity closest to those of the experimental values. Simulated densities approached a final density of 1.05–1.08 g/cm3 which compared favorably with the experimental values of 1.16–1.21 g/cm3 for phenol-formaldehyde resins. The RMD calculations were run using LAMMPS software at temperatures of 1250 K and 3000 K using the ReaxFF force field and employing an in-house routine for removal of products of condensation. The species produced during RMD correlated with those found experimentally for polyphenolic systems and rearrangements to form cyclopropane moieties were observed. At the end of the RMD simulations a glassy carbon char resulted.
Highlights
The field of reactive molecular dynamics of polymers has progressed considerably since the review by Lyon et al in 2003 that studied models consisting of 20 monomer chains of the polymers under investigation [1]
Banerjee, and Mohanty [2] studied the combustion and pyrolysis of brown coal by reactive molecular dynamics (RMD), and they concluded that hydrogen was abstracted to form water and that the levels of simulated formaldehyde agreed with the experimental literature
Most relevant to this work, Liu at al. [5] studied the pyrolysis of high-density polyethylene using RMD and a model of 7000 atoms and they found that the reaction time for 90% of the loss of structure agreed with the experimental values
Summary
The field of reactive molecular dynamics of polymers has progressed considerably since the review by Lyon et al in 2003 that studied models consisting of 20 monomer chains of the polymers under investigation [1]. There have been several papers on reactive molecular dynamics (RMD) of bituminous coal in particular. Banerjee, and Mohanty [2] studied the combustion and pyrolysis of brown coal by RMD, and they concluded that hydrogen was abstracted to form water and that the levels of simulated formaldehyde agreed with the experimental literature. Zan et al [3] studied the initial reaction of sub-bituminous coal using RMD and Illinois no. [5] studied the pyrolysis of high-density polyethylene using RMD and a model of 7000 atoms and they found that the reaction time for 90% of the loss of structure agreed with the experimental values. An interesting study [7] used RMD to probe the oxidation resistance in hydrogen peroxide of ultra-high molecular weight polyethylene and polyoxymethylene.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
