Thermal degradation of natural rubber/ZNO nanocomposites

Nanoparticies have been widely used to enhance the properties of natural rubber (NR). In the present paper a novel nanocomposite was developed by blending nano-ZnO slurry with prevulcanized NR latex, and the thermal degradation process of pure NR and NR/ZnO nanocomposites with different nano-ZnO loading was studied with a Perkin Elemer TGA-7 thermogravimetric analyzer. The thermal degradation parameters of NR/ZnO (2 parts ZnO per hundred dlY rubber) at different heating rates (<i>B</i>s) were studied. The results show that the thermal degradation of pure NR and NR/ZnO nanocomposites in nitrogen is a one-step reaction. The degradation temperatures of NR/ZnO nanocomposite increase with an increasing <i>B</i>. The peak height (<i>R</i>_p) on the differential thermogravimetric curve increases with the increase of <i>B</i>. The degradation rates are not affected significantly by<i> B</i>, and the average values of thermal degradation rate <i>C</i>_<i>p</i> and <i>C</i>_f are 44.42 % and 81.04 %, respectively. The thermal degradation kinetic parameters are calculated with Ozawa-Flynn-Wall method. The activation energy (<i>E</i>) and the frequency factor (<i>A</i>) vary with ecomposition degree, and can be divided into three phases corresponding to the volatilization of low-molecular-weight materials, the thermal degradation ofNR main chains and the decomposition of residual carbon.<br />