3.1.2. Thermogravimetric Analyses (TGA)

Figure 9 shows the thermogravimetric curves of the ECC, ECC-R-120, and ECC-R-160 samples in air and nitrogen flow.

**Figure 9.** Thermogravimetric curves of ECC sample and the rubber functionalized mixtures ECC-R-120 and ECC-R-160 in air and nitrogen flow.

Comparing the TGA curves of the ECC-R-120 and ECC-R-160 samples with that of sample ECC, it is evident that the thermal stability of the functionalized samples is higher than that of the unfunctionalized resin ECC. Table 2 shows data from TGA analyses performed in air and nitrogen flow for the ECC, ECC-R-120, and ECC-R-160 samples. The initial degradation temperature (Td5%), expressed as temperature corresponding to a weight loss of 5 wt%, presents an increase of about 20 ◦C and 30 ◦C for the samples ECC-R-120 and ECC-R-160, respectively. The behaviour in nitrogen flow is the same as observed in air; in this last case, the initial degradation temperature (Td5%) of the samples ECC-R-120 and ECC-R-160 manifests an increase of 13 ◦C and 7 ◦C, respectively, with respect to the ECC sample.

**Table 2.** Data of TGA analyses performed in air and nitrogen flow for ECC, ECC-R-120, and ECC-R-160 samples.


\*Td5%: temperature corresponding to a weight loss of 5 wt%.

Considering the more reactive environment, the tests performed in air, the functionalized precursor presents a higher thermal stability than the raw precursor.

The functionalization reaction obtained at 160 ◦C allows for obtaining a modified precursor with greater thermal stability achieving a Td5% value up to 220 ◦C.
