Atomistic analysis of PBO carbonization process with ReaxFF Reactive Force Field*

There is a constant need for an alternative precursor polymer for the carbon fibers (CFs) production with lowering the costs without compromising CFs mechanical properties. We report an atomistic simulation of a direct carbonization of poly(p-phenylene-2,6-benzobisoxazole) (PBO) that can be transform into high strength carbon fiber. The possibility of using various heating rates is considered and observed gaseous molecules as well as 6-membered all-carbon ring production analyzed. Based on our ReaxFF atomistic-scale reactive molecular dynamics simulations of the direct carbonization of the PBO we proposed a mechanism that might be responsible for an improvement of the mechanical characteristics of the PBO-based CFs with ultrafast heating rate treatment observed in experiment.