Material description

Material ID: OTH01

Material type: Predominantly organic composition rich in aromatics, such as cellulose-based and/or phenolic polymers, with an inorganic filler.

Polymer: Phenolic binder and cellulose (95%)

Additives (fire retardants, fillers or traces of inorganic elements): Phosphorus (4%), traces of other elements (<1%)

Core thickness: 9.22mm

 

Table 1. Estimated mass concentration of compounds.
CompoundMass Concentration (%)
Phenolic binder and cellulose (-)95
Phosphorus (P)4
Traces of calcium (Ca)<1
Traces of silicon (Si)<1
Traces of sulfur (S)<1
Traces of magnesium (Mg)<1
Traces of iron (Fe)<1
Traces of sodium (Na)<1
Traces of potassium (K)<1

A. Material composition identification

A.1 Attenuated total reflection – Fourier transform infrared spectroscopy (ATR-FTIR)

Table 2. FTIR compound identification.
Identified Compounds
Phenolic binder and cellulose (-)
...
Figure 1 . FTIR spectra: Absorbance percentage versus wavenumber from the sample.
...
Figure 2. FTIR spectra: Absorbance percentage versus wavenumber from the sample and the identified compounds.

A.2 Energy Dispersive X-Ray Fluorescence (EDXRF)

Table 2. Inorganic elements and their mass concentration identified with EDXRF.
ElementMass Concentration (%)
P4
Ca<1
Si<1
S<1
Mg<1
Fe<1
Na<1
K<1
...
Figure 3. EDXRF spectra. Counts vs energy. Identified elements are shown as vertical lines.

B. Thermogravimetric analysis

Table 3. Mass fraction of residue after thermal decomposition.
ConditionFraction of mass residue at 800°C
Non-oxidative (nitrogen)0.46
Oxidative (air)0.08
Table 4. Temperature and amplitude of main peaks in non-oxidative conditions.
Peak IDTemperature peak (°C)Amplitude of peak (°C-1)
Peak 12868.11 x 10-3
Table 5. Temperature and amplitude of main peaks in oxidative conditions.
Peak IDTemperature peak (°C)Amplitude of peak (°C-1)
Peak 12859.02 x 10-3
Peak 25462.63 x 10-3
...
Figure 4. Normalised mass (solid line) and derivative of the normalised mass (dashed line) in 150 ml min-1 of nitrogen and a heating rate of 20°C min-1.
...
Figure 5. Normalised mass (solid line) and derivative of the normalised mass (dashed line) in 150 ml min-1 of air and a heating rate of 20°C min-1 .

C. Gross Heat of Combustion

Table 7. Gross Heat of Combustion individual results for sample.
TrialΔHc [kJ g-1]
Trial 119.70
Trial 219.75
Trial 319.81
Average19.75
Std dev0.06

D. Ignition parameters

Table 8. Summary of ignition parameters for sample.
Critical heat flux for ignitionIgnition temperatureTotal heat transfer coefficient of lossesApparent thermal inertia
q̇″cr [kW m−2]Tig [°C]hr [W m-2 K-1]kρc [kW2 m-4 K-2 s]
47.5050252.301.613
...
Figure 6. Time-to-ignition vs incident radiant heat flux for samples.

E. Burning behaviour

Table 9. Summary of key burning behaviour metrics.
Heat fluxTestTime to ignitionFraction of mass residuePeak heat release rateTotal energy released
q̇″inc [kW m-2] tig [s]mres [-]q̇″p [kW m-2]Qt [MJ m-2]
35 kW m-2
Test 16080.4683.6041.97
Test 26530.4598.5943.04
Avg6300.4591.0942.51
50 kW m-2
Test 12790.41105.7565.81
Test 23570.42112.4886.35
Avg3180.41109.1276.08
60 kW m-2
Test 1490.39140.30132.95
Test 2650.8371.816.02
Avg570.61106.0669.48
80 kW m-2
Test 1----
Test 2----
Avg----
...
Figure 7. Normalised mass loss over time for samples tested with 35, 50, 60 and 80 kW m-2.
...
Figure 8. Heat release rate per unit area over time for samples tested with 35, 50, 60 and 80 kW m-2.
Table 10. Effective Heat of Combustion individual results for sample.
TestΔHc [kJ g-1]
35 kW m-2 (Test 1)5.87
35 kW m-2 (Test 2)5.97
50 kW m-2 (Test 1)8.57
50 kW m-2 (Test 2)10.88
60 kW m-2 (Test 1)16.10
60 kW m-2 (Test 2)2.61
80 kW m-2 (Test 1)-
80 kW m-2 (Test 2)-
Average8.33
Std dev4.72

F. Flame Spread

Table 11. Minimum heat flux for flame spread rate and minimum flame spread rate for sample.
Orientationq̇″min.spread [kW m-2]Vf.min [mm s-1]
Horizontal360.40
Vertical100-
...
Figure 9. Lateral flame spread rate versus heat flux.
...
Figure 10. Vertical flame spread rate versus heat flux.
Table 12. Flame spread parameter results for sample.
OrientationTrial(kρcpΦh2)12 [m32 s12 kW-1]Φ [kW2 m-3]
Horizontal1100-
Horizontal2100-
Vertical1100-
Vertical2100-
Additional information:

Sample ignited but had insufficient spread to apply flame spread theory.