• activation energy;
  • composites;
  • mechanical properties


High-density polyethylene (HDPE)/jatropha deoiled cake (JOC) composites were fabricated by melt compounding; the molded specimens were tested for their tensile properties and water absorption. The thermal properties were investigated with thermogravimetry (TG) analysis, differential scanning microscopy (DSC), and limiting oxygen index testing. The degradation kinetic parameters were calculated with the Friedman and Freeman–Carroll models. The morphology of the tensile fractured composites was investigated by scanning electron microscopy. The results show that the introduction of JOC significantly reduced the tensile strength, percentage elongation at break, and modulus. On the one hand, JOC increased the water uptake. The TG and differential TG of JOC showed that the thermal degradation took place in two stages. The neat HDPE revealed a single degradation stage, whereas the blend showed three degradation stages. The composites' initial degradation temperature decreased; however, the residue chars increased with increasing JOC content. The activation energies (Ea's) were lower in the case of the blends than that corresponding to HDPE. The DSC results showed decreases in the melting temperature and degree of crystallinity of the composites. A considerable enhancement of the flame-retardant properties was observed for the composites. These experimental results suggest a synergetic effect caused by the coprocessing of the two materials together. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012