Thermal decomposition kinetics and mechanism of low-temperature hydrogenated acrylonitrile butadiene rubber composites with sodium methacrylate

Thermal decomposition processes and mechanism of low-temperature grade hydrogenated acrylonitrile butadiene rubber(LTG-HNBR) composites with sodium methacrylate(NaMAA) were investigated by thermogravimetric analysis(TGA) and Fourier transform infrared spectroscopy(FTIR) coupling technology in this article. The results of TGA demonstrate that the addition of NaMAA can enhance the thermal decomposition temperature of the rubber. Moreover, it was found that the composites spent more activation energies to decompose than pure rubber by the calculations of multiply heating rate method. Time-resolved FTIR spectra show that NaMAA affects the initial decomposition of the composites. But in the following process, the composites maintained a similar behavior to the matrix. During the decomposition, PNaMAA nanostructures, in-situ generated by NaMAA, helped reduce the diffusion speed of decomposition products and thus improved the thermal stability of the composites. We believe that these findings can provide some guides to direct the applications of LTG-HNBR composites with unsaturated metal methacrylates.