Curing kinetics of composites based on benzoxazine resin and microcrystalline cellulose modified by phosphorus salt

A comprehensive investigation into the curing kinetics of composites based on bisphenol A aniline benzoxazine resin (BA-a) and microcrystalline cellulose (MCC) modified by phosphorylation (MCC-pH), was conducted in this study. For this purpose, differential scanning calorimetry (DSC) analysis, at different heating rates, was used to examine the curing process. The kinetic parameters as a function of conversion were determined using isoconversional approaches, i.e., iterative Kissinger-Akahira-Sunose (it-KAS), Trache-Abdelaziz-Siwani methodology (TAS), and Vyazovkin methodology. The incorporation of MCC-pH reduced considerably the curing temperatures, indicating their catalytic effect. A combination of isoconversional methods and multi-step kinetic fitting was done to elucidate the effect of adding MCC-pH on BA-a curing. The reported data exhibited the enhanced reactivity of the composite systems, which was associated with the acceleration of the regular polymerization reaction. The possible pathway of the polymerization in the presence of phosphorylated cellulose was also discussed.