## 4 Conclusions  
Two series of foams with cinnamon extract were obtained: one with flame retardant (C_0t) and the other without flame retardant (CU_0t). The results of this research showed an improvement of some properties of foams with biofililler. The measurement of the color indicates an increase in the red color of foams subjected to conditioning (accelerated degradation conditions) and an increase in the color of blue in thermostated foams (for 48 hours in an exhaust dryer). In cinnamon-modified RPU/PIR foams with and without flame retardants was observed decrease in compressive strength from 251.63 kPa (W_0t foam) to 147.29 kPa (C15_0t foam) and from 361.39 kPa (WU_0t) to 91.93 kPa (CU15_0t). The observed decrease of brittleness was from 13% to 11% (in C series) and an increase from 16% to 45% in CU series of foams. In addition, increasing amount of cinnamon extract in the C series (from 5% to 15%) increased the H\({}_{1}\) enthalpy at a temperature of about 80 \({}^{\circ}\)C-95 \({}^{\circ}\)C (from 25.75 J/g, W0t to 36.53 J/g, C15_0t, and to 54.94 J/g, CU15_0t). The oxygen index was between 18.5% and 20.2% (C series) and between 23.7% and 24.7% (CU series). The combustion residue (CR) after the burning of foams containing cinnamon extract and flame retardant (series C_0t) increased by about 10% in relation to the foam without biofililler (W_0t). For a series without flame retardant (CU_0t), the CR increased by about 30% in relation to the CR of the reference foam WU_0t. The difference in CR between reference foams W_0t and WU_0t was about 40%. W_0t foam, containing Antiblaze TMCP, had a CR of 83.44 and WU_0t was 37.72%. The addition of cinnamon extract contributed to increasing the foams' CR to 91.68% for C15_0t and to 63.33% for CU15_0t. Cinnamon-based filler showed synergism with Antiblaze TMCP in reducing flammability. Foams containing flame retardant and cinnamon extract (C_0t series) were characterized by the highest combustion residue. Conditioning caused decrease in compressive strength for C_1t series of foam by about 20 kPa (in comparison to the C_0t series). Destruction of characteristic bonds (e.g., cracking urethane bond) occurred was a result of a combined effect of temperature, humidity, and UV radiation in the conditioner. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Foam Symbol**} & **Cell/Hole Height (\(\mu\)m)** & **Cell/Hole Width (\(\mu\)m)** & **Anisotropy Coefficient** & **Cell/Hole Surface Area (mm\({}^{2}\))** & **Content of Cell/Hole per Area Unit (cell/mm\({}^{2}\))** \\ \hline W\_0t & 606.6 \(\pm\) 2 & 540.7 \(\pm\) 2 & 1.12 \(\pm\) 0.00 & 0.258 \(\pm\) 0.001 & 3.88 \(\pm\) 0.01 \\ C5\_0t & 399.0 \(\pm\) 1 & 326.4 \(\pm\) 1 & 1.22 \(\pm\) 0.00 & 0.102 \(\pm\) 0.001 & 9.80 \(\pm\) 0.01 \\ C15\_0t & 325.3 \(\pm\) 1 & 322.4 \(\pm\) 1 & 1.01 \(\pm\) 0.00 & 0.084 \(\pm\) 0.001 & 11.92 \(\pm\) 0.03 \\ W\_1t & 367.7 \(\pm\) 1 & 340.9 \(\pm\) 1 & 1.08 \(\pm\) 0.00 & 0.098 \(\pm\) 0.001 & 10.20 \(\pm\) 0.03 \\ C5\_1t & 359.7 \(\pm\) 2 & 348.1 \(\pm\) 1 & 1.05 \(\pm\) 0.00 & 0.085 \(\pm\) 0.001 & 11.77 \(\pm\) 0.03 \\ C15\_1t & 260.4 \(\pm\) 2 & 249.0 \(\pm\) 2 & 1.04 \(\pm\) 0.00 & 0.051 \(\pm\) 0.001 & 19.69 \(\pm\) 0.04 \\ C15\_0t & 598.4 \(\pm\) 2 & 613.0 \(\pm\) 2 & 0.98 \(\pm\) 0.00 & 0.288 \(\pm\) 0.001 & 3.47 \(\pm\) 0.01 \\ C15\_0t & 563.8 \(\pm\) 2 & 558.2 \(\pm\) 2 & 0.97 \(\pm\) 0.00 & 0.255 \(\pm\) 0.001 & 3.52 \(\pm\) 0.01 \\ CU5\_1t & 981.1 \(\pm\) 2 & 978.2 \(\pm\) 2 & 1.00 \(\pm\) 0.00 & 0.754 \(\pm\) 0.001 & 1.33 \(\pm\) 0.00 \\ CU15\_1t & 980.3 \(\pm\) 2 & 916.4 \(\pm\) 2 & 1.06 \(\pm\) 0.00 & 0.705 \(\pm\) 0.001 & 1.42 \(\pm\) 0.00 \\ \hline \hline \end{tabular}
\end{table} 
Table 12: Results of SEM micrograph analysis. **Author Contributions:** Conceptualization: [PERSON]; methodology: J.L., M.I., and K.M. ; software: [PERSON]; validation: [PERSON]; formal analysis: [PERSON] and M.B. ; investigation, J.L. ; data curation: [PERSON]; writing--original draft preparation: [PERSON]; visualization: [PERSON]; supervision: [PERSON].