Degradation kinetics of epoxidized soybean oil composites filled with sisal fiber

Abstract

AbstractEpoxidized soybean oil (ESO) composites were cured with methyl tetrahydrophthalic anhydride (MTHPA) and 2,4,6‐tris(dimethylaminomethyl)phenol (DEH 35) as a catalyst, sisal fibers were added at 10% and 30% of percent per weight. Composites curing was monitored using Fourier transform infrared spectroscopy, whereas the thermal stability and the degradation kinetics were investigated using thermogravimetry (TG). ESO/MTHPA/DEH35/S10 and ESO/MTHPA/DEH35/S30 composites displayed curing temperatures approximately 100°C lower related to ESO/MTHPA/DEH35, as well as higher degree of conversion. Sisal addition improved the thermal stability, shifting the weight loss shifting the weight loss onset to higher temperature (from 82 to 120°C). Thermal degradation energy was determined using Friedman, Kissinger‐Akahira‐Sunose and Ozawa‐Flynn‐Wall models. Sisal significantly increased , especially in the intermediate phase (α = 0.2 and 0.8). The degradation kinetics was investigated by TG, and the degradation mechanisms modeled using Kamal‐Sourour, Sestack‐Berggren, and 1st order (F1), showed excellent fit, with R2 > 0.99. Acquired results demonstrate that sisal fiber addition benefited the curing process and increased the thermal stability of ESO composites.