# Fire Behavior of Wood-Glass and Jute-Glass Hybrid Laminates Manufactured by Vacuum Infusion
## 3 Results and Discussion
The residue appears to be around 60% of the original weight entirely attributable to the glass mat, as can also be seen from the photograph in Figure 3. The combustion time was almost halved with respect to the neat resin (161 s), and the peak of heat release appeared earlier (TTP 94 \(\pm\) 12 s vs. 166 \(\pm\) 3 s). The opposite formulation \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Sample** & **TTI (s)** & **TTP (s)** & **pHRR** & **THR** & **TSR** & **SEA w.** & **MARHE** & **FIGRA** & **Residue** \\  & & **(kW/m\({}^{2}\))** & **(MJ/m\({}^{2}\))** & **(m\({}^{2}\)/m\({}^{2}\))** & **(m\({}^{2}\)/kg)** & **(kW/m\({}^{2}\))** & **(kW/m\({}^{2}\)\(\times\)s)** & **(\%)** \\ \hline Polyester & \(58\pm 1\) & \(166\pm 3\) & \(971\pm 103\) & \(116\pm 12\) & \(7361\pm 839\) & \(1227\pm 8\) & \(492\pm 3\) & \(5.8\pm 0.5\) & \(0.1\pm 0.1\) \\ G5 & \(55\pm 15\) & \(94\pm 12\) & \(322\pm 6\) & \(25.1\pm 23\) & \(1365\pm 191\) & \(825\pm 92\) & \(141\pm 11\) & \(3.5\pm 0.4\) & \(62.4\pm 2.3\) \\ J5 & \(45\pm 1\) & \(105\pm 6\) & \(794\pm 45\) & \(53.0\pm 7.6\) & \(2484\pm 216\) & \(825\pm 31\) & \(332\pm 23\) & \(7.5\pm 0.6\) & \(0.5\pm 0.1\) \\ GJGJG & \(64\pm 3\) & \(121\pm 8\) & \(395\pm 7\) & \(40.2\pm 5.1\) & \(1860\pm 49\) & \(835\pm 90\) & \(191\pm 8\) & \(3.3\pm 0.2\) & \(34.7\pm 1.9\) \\ WGWGW & \(53\pm 3\) & \(165\pm 8\) & \(453\pm 43\) & \(76.5\pm 5.8\) & \(2873\pm 188\) & \(697\pm 31\) & \(270\pm 13\) & \(2.7\pm 0.3\) & \(1.9\pm 1.1\) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Main data and standard deviations measured of combustion in the cone calorimeter tests. sample, the J5 one, composed of resin and organic material, presented a behavior similar to the neat resin, with an even sharper peak at 794 \(\pm\) 45 kW/m\({}^{2}\) and a TTP of 105 \(\pm\) 6 s. The entire combustion process appeared to be the fastest of the samples examined, with an average combustion phase of around 115 s. The two samples containing the hybrid layers between the glass and organic substances presented similar behavior to each other, with the presence of a first small peak in the first stages of combustion (20-30 s from starting of flame), probably due to the resin's presence. Subsequently, in both cases, there was a protective layer formation phase, which could be made of glass or carbonized organic material or their combination. During this period, the HRR curve essentially remained constant or decreased significantly. This phase lasted for a shorter time for the GJGJG sample, which then presented the HRR peak of 395 \(\pm\) 7 kW/m\({}^{2}\) at 121 \(\pm\) 8 s, while it lasted longer for the WGWGW sample and caused a higher-in-intensity peak of 453 \(\pm\) 43 kW/m\({}^{2}\), postponed until 165 \(\pm\) 8 s. Probably, the WGWGW compared to the GJGJG sample is able to produce a good-quality protective shield and, therefore, postpone the occurrence of the peak. However, by having a larger quantity of organic content than the GJGJG, it produces a slightly higher peak. Figure 3: Appearance of the samples before and after the cone calorimeter tests. Figure 2: Heat release rate as a function of time for each group analyzed (**A**) and the average values of the heat release rate and confidence interval of 95% (**B**). Different letters above the errors in each group represent a statistical difference. Finally, it is important to note that the WGWGW hybrid laminate, predominantly composed of wood veneers, especially in its surface layer, exhibited a heat release time that ranged on average from 53 s to 255 s. This range is significantly higher compared to the other laminates, showing fire resistance and delayed carbonization. These results highlight the effectiveness of hybrid laminates in improving their properties when exposed to heat, especially those wherein the hybridization chosen was with wood and glass [24; 26].