Simulating the Initial Stage of Phenolic Resin Carbonization via the ReaxFF Reactive Force Field

Pyrolysis of phenolic resins leads to carbon formation. Simulating this resin-to-carbon process atomistically is a daunting task. In this paper, we attempt to model the initial stage of this process by using the ReaxFF reactive force field, which bridges quantum mechanical and molecular mechanical methods. We run molecular dynamics simulations to examine the evolution of small molecules at different temperatures. The main small-molecule products found include H2O, H2, CO, and C2H2. We find multiple pathways leading to H2O formation, including a frequent channel via β-H elimination, which has not been proposed before. We determine the reaction barrier for H2O formation from the reaction rates obtained at different temperatures. We also discuss the relevance of our simulations to previous experimental observations. This work represents a first attempt to model the resin-to-carbon process atomistically.