Kinetic analysis of poly(ethylene oxide)/lithium montmorillonite nanocomposites

Abstract

Poly(ethylene oxide)/lithium montmorillonite (PEO/LiMMT) nanocomposites were prepared by melt intercalation method. The degradation of PEO/LiMMT nanocomposites was performed by non-isothermal thermogravimetry in nitrogen atmosphere at four heating rates (2.5, 5, 10 and 20 °C min−1). The obtained data were used for the kinetic analysis of the degradation process. Kinetic analysis was performed using the isoconversional Friedman method in combination with the multivariate nonlinear regression method. Kinetic analysis revealed the complexity of the thermal degradation process for both pure PEO and all PEO/LiMMT nanocomposites. The contribution of the each individual degradation stage was determined, and each of them was independently analyzed. Kinetic parameters (activation energy, pre-exponential factor and kinetic model) were also calculated for each degradation stage of all investigated samples.