Fig. 4 shows the thermogravimetric analysis of the samples in
nitrogen atmosphere. The control NR sample degrades in a single
step with a strong weight loss centered at 379 C. The addition of
3 phr of TRGO slightly improves the thermal stability of natural
rubber, showing a shift of the curve to higher temperatures, about
3–4 C. In the case of nanocomposite with TRGO dispersed in SDS,
two stages of decomposition are observed, the first at 230 C with a
weight loss of about 3% related to the degradation of the surfactant
and a second weight loss at 382 C associated with the polymeric
matrix. On the other hand, it is observed that only a fraction of
SDS is decomposed at the degradation temperature corresponding
to this surfactant. This could be likely due to the partial entrapment
of this compound in the polymer matrix.