Identifying the role of the acidic comonomer in poly(acrylonitrile-co-itaconic acid) during stabilization process through low temperature electron beam irradiation

The stabilization behavior of poly (acrylonitrile-co-itaconic acid) (PAI) by using electron beam irradiation (EBI) was investigated to identify the role of itaconic acid (IA). EBI was employed as a tool to generate radicals, which induced a “cold” stabilization reaction at room temperature and excluded ionic and thermally induced radical-mediated stabilization reactions. Fourier transform infrared spectroscopy was employed to quantitatively track the structural evolution of the PAI during stabilization. The stabilization reactions of the PAIs successfully progressed with higher EBI dosages at room temperature. More efficient cyclization reactions were observed for the PAIs with increased amounts of IA, because of the increased amorphous regions of the PAIs with a higher level of IA. The extents of the cyclization values of the PAIs normalized to their crystallinity values were similar to each other regardless of the IA contents, indicating the absence of an ionic initiation mechanism of IA at room temperature. In addition, the incorporation of IA units in PAIs increased the polarity and oxophilicity of the PAIs, thereby inducing facilitated oxygen uptake reactions, as evidenced by the high concentrations of conjugated carbonyl groups in the stabilized structures. [Display omitted] •The role of itaconic acid (IA) in precursor for carbon material is investigated.•Electron beam irradiation is used to isolate radical-mediated stabilization at RT.•FT-IR is employed to quantitatively track the structural evolution of precursor.•IA facilitates stabilization by increasing amorphous content/polarity of precursor.