## 3 Results and Discussion  
The LOI and UL-94 tests results are summarized in Table 3 where it can be seen that adding solely 15% FR to the reABS affected the nanocomposites LOI, by increasing it by 7%. Pure reABS showed an HB type behavior (i.e., slow burning) at burning and a LOI value of 18.5%, which is in agreement with the studies conducted by [PERSON] et al. [1] and [PERSON] et al. [6]. When the FR content was as low as 15 wt%, the LOI value increased to 25.5% indicating a significant influence of FR on LOI (Limiting oxygen index). \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Specimen**} & \multirow{2}{*}{**LOI [\%]**} & **Behavior at Burning after** & \multirow{2}{*}{**Drop Type**} & \multirow{2}{*}{**UL 94**} \\  & & **First Ignition** & & \\ \hline reABS & 18.5 & burnt completely & burning drops & HB \\ reABS 15\% FR & 25.5 & burned 10 s & burning drops & V-2 \\ reABS 1% OMT & 20.8 & burnt completely & burning drops & HB \\ reABS 15\% OMT & 15\% FR & 25.8 & burned 9 s & no burning drops & V-1 \\ reABS 15\% OMT 18\% FR & 27.7 & burned 2 s & no drops & V-0 \\ reABS 15\% OMT 20\% FR & 28 & burned 0 s & no drops & V-0 \\ reABS 2\% OMT & 22 & burnt completely & burning drops & HB \\ reABS 2\% OMT 15\% FR & 27 & burned 1 s & no drops & V-0 \\ reABS 2\% OMT 18\% FR & 28.3 & burned 0 s & no drops & V-0 \\ reABS 2\% OMT 20\% FR & 28.7 & burned 0 s & no drops & V-0 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Limiting Oxygen Index (LOI) and UL 94 tests results. The maximum LOI value observed, 28.7%, was for the nanocomposites reABS 2% OMT 20% FR. Thereafter, the LOI value for the nanocomposite with 18-20 wt% FR was nearly constant while the influence of OMT is rather important. In addition, as can be seen from Table 3, the material composition plays an important role and there is a synergy between adding OMT and FR as is reported in the literature [13]. Adding just one component, OMT or FR, does not give a clear advantage on burning rate, as can be seen from Table 3, where better results in terms of burning are obtained for the samples with both OMT and FR. Furthermore, it can be noted that the addition of OMT maintains the reABS behavior at burning (i.e., HB--slow burning [6]), while the addition of 15% FR gets a V-2 rating. On the other hand, when the percentage of FR increases, the burning rate increased to V-0. The only exception is reABS 1% OMT 15% FR that obtained a V-1 score for the burning rate, even though the LOI result was rather good. In this context, the addition of both OMT and FR to enhance the reABS behavior at burning can clearly be recommended. The cone calorimeter is the most significant bench scale tool in the fire testing area being the most helpful for fire safety researchers to quantitatively examine the materials flammability [7; 8]. In this research, cone calorimetric tests were run with a heat flux of 50 kW/m\({}^{2}\) to investigate the fire performance of reABS and the respective configurations are reported in Table 2. The cone-calorimeter tests results are summarized in Table 4 and Figures 1-6, where:  
* TTI is the time taken for the specimen to ignite at 50 kW/m\({}^{2}\) flux;
* THR is the total heat released per unit area during the entire test for the tested thickness of product;
* PHRR is the peak heat release rate;
* Residue is measured as percentage;
* Effective heat of combustion is the energy produced per kg of the product. It is averaged over the length of the test;
* FIGRA is the growth rate of the burning intensity, HRR, during a test and is calculated as the maximum value of the function (heat release rate)/(elapsed test time). In Table 4, the average standard deviation of all measured mass loss calorimeter values are TTI = \(\pm\)3 s; PHRR = \(\pm\)30 kW/m\({}^{2}\); time of PHRR = \(\pm\)5 s; and residue = \(\pm\)0.2%. From Table 4 an improvement of the peak heat release rate (PHRR) is visible when the FR and OMT, or both, were added to the polymer.