Non-isothermal degradation kinetics of Ethylene-Vinyl Acetate Copolymer nanocomposite reinforced with modified Bacterial Cellulose Nanofibers using advanced isoconversional and master plot analyses

The non-isothermal degradation kinetics of Ethylene-Vinyl Acetate (EVA) Copolymer containing modified Bacterial Cellulose Nanofibers (MBC) was reported to determine its service temperature. The apparent activation energies are estimated using advanced isoconversional and various model-free methods, which indicate the two-stage degradation mechanism. The kinetic mechanisms are determined using the differential f(α) and combined Z(α) master plots by comparing the experimental plot with the theoretical master curves. The results on 'FZ master plots' reveal that the degradation proceed via D2 mechanism in the range of (α ≤ 0.3) exhibiting that the simultaneous acetate groups and MBC degradations is controlled by two-dimensional diffusion of the volatiles. However, for (α ≥ 0.3) there is a gradual change to F1 mechanism that means the scission of the residual main chains of EVA is performed by random nucleation with one nucleus on the individual particle. The calculated kinetic triplets are used to predict the lifetime.