Study on the Thermooxidative Degradation Kinetics of Tetrafluoroethylene-Ethylene Copolymer Filled with Rice Husks Ash

The thermooxidative degradation kinetics of tetrafluoroethylene-ethylene copolymer (TFE-E) and its composites filled with 10 mass% black rice husks ash (BRHA), white rice husks ash (WRHA) or Aerosil A200 Degussa (AR) in air was studied using the Coats-Redfern calculation procedure. The thermooxidative degradation of these composites occurs in two stages and their most probable kinetic mechanisms were established, as well as the values of the activation energy E, frequency factor A in the Arrhenius equation and the changes of Gibbs free energy Δ G ^≠, enthalpy Δ H ^≠ and entropy Δ S ^≠ for the formation of the activated complex from the reagents, respectively. The thermooxidative degradation of the samples studied was accompanied by kinetic compensation effect. The lifetime values were calculated at different temperatures to conclude that the use of BRHA as filler reduced lifetime to the highest extent.