The growth of the use of polymer composite materials has been a phenomenon since 1960, with diverse applications in spacecraft, aircraft, boats, ship, automobiles, civil infrastructure, sporting goods, and consumer products. In addition, the use of composites will continue to grow in the coming years with emerging end-use such as large bridge structures, engine machinery, offshore platforms, computer hardware, and biomedicals devices. However, a critical challenge facing the growing use of polymer composites is their high combustibility.
Over the years, researchers have made several attempts to come up with solutions to the problems associated with the use of polymer composite materials. The most successful attempt reported in the literature is the strategy of incorporating a novel chemical substance known as a fire retardant into the polymer matrix to suppress fire (heat release and temperature) and minimise the gas emission species that could be a source of toxicity via the mechanism of the solid phase and gaseous phase phenomena [4,8,9,10].
The aim of this review is to carry out an extensive study on the various classes of thermal/fire facilities used for the characterisation of polymer composite materials and to examine different test parameters with respect to their gaseous emission properties. This will be achieved via the following specific objectives: Collection of data from top five publishers; Classification of thermal and fire testing facilities; Evaluation of various thermal/fire parameters of polymer composites; Gas emission assessment of some composite materials.
Regardless of the scale used, it is vital to ensure that the fire reaction tests are carried out in conditions that precisely reproduce the type of fire in which the composite materials will be subjected.
At high temperatures, the residue does not emit any dangerous gas and acts as an effective insulation layer on the sample’s surface, protecting the underlying material from fire.
Researchers have performed quite a number of studies on the fire behaviour and the protection of polymer composite materials used especially as vital components in the transport sectors and building element under fire condition [109]. The bench-scale platform of the medium scale has provided significant fire testing parameters that indicate the fire reaction and fire resistance of the materials assessed (as shown in Table 3 , Table 4 , Table 5 and Table 6 ) e.g., a cone calorimeter test (CCT), limiting oxygen index (LOI), and underwriter’s laboratories (UL-94). Thus, the results have been a useful guide in the evaluation of the fire hazard risk and the smoke and toxic gases examination.
Specimens (Codes) | pHRR (kW/m2) | THR (MJ/m2) | TTI (s) | pHHR/tig (kWm2s1) | Residual Mass (%) | TSP (m2/kg) | TSR (m2/m2) | SEA (m2/kg) | CO Yield (g/kg) | CO2 Yield (kg/kg) | LOI | UL-94 | Citations |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
A-10 | 361 | 67 | 31 | 16.2 | - | 20.9 | - | 762 | 0.128 | - | 25.4 | HB | |
B-10 | 429 | 60 | 54 | 8.1 | - | 20.4 | - | 838 | 0.199 | - | 25.0 | HB | |
AS-5 | 348 | 63 | 58 | 6.0 | - | 21.8 | - | 918 | 0.333 | - | 26.4 | HB | |
BS-5 | 335 | 59 | 60 | 5.6 | - | 19.1 | - | 756 | 0.053 | - | 27.7 | HB | [26] |
BS-0 | 433 | 66 | 60 | 8.2 | - | 17.7 | - | 505 | 0.074 | - | 28.0 | HB | |
B1S-5 | 306 | 55 | 60 | 5.1 | - | 18.9 | - | 728 | 0.268 | - | 28.8 | HB | |
B1S-10 | 416 | 63 | 59 | 5.8 | - | 16.7 | - | 614 | 0.279 | - | 29.0 | HB | |
Pure PLA | 752 | 171.1 | 37 | 209 | −3.66 | 40.8 | - | - | 0.037 | - | 21.5 | NR | |
MX0.5 | 920 | 170.4 | 32 | 209 | −0.30 | 47.5 | - | - | 0.030 | - | 20.0 | NR | |
MX1.0 | 803 | 167.7 | 32 | 207 | 0.00 | 41.0 | - | - | 0.028 | - | 20.0 | NR | |
MX2.0 | 715 | 178.9 | 35 | 254 | 0.53 | 20.8 | - | - | 0.035 | - | 20.5 | NR | [27] |
F12.0 | 431 | 136.3 | 41 | 246 | 4.04 | 457.4 | - | - | 0.097 | - | 30.0 | V-1 | |
F11.5MX0.5 | 263 | 144.5 | 39 | 389 | 5.86 | 178.1 | - | - | 0.062 | - | 33.0 | V-0 | |
F11.0MX1.0 | 266 | 142.7 | 35 | 415 | 7.82 | 244.3 | - | - | 0.059 | - | 34.5 | V-1 | |
F10.0MX2.0 | 410 | 149.6 | 30 | 252 | 6.36 | 282.0 | - | - | 0.072 | 28.0 | V-1 | ||
Pure WPC | 347 | 191 | 26 | - | 16.4 | - | - | - | - | - | - | - | |
WPC + 3wt% FR | 323 | 179 | 23 | - | 22.9 | - | - | - | - | - | - | - | [28] |
WPC +10wt% FR | 311 | 175 | 22 | - | 25.2 | - | - | - | - | - | - | - |
Calorimeter (irradiance, 50 kW/m2), LOI and UL-94 results. TSP: total smoke production, TSR: total smoke release SEA: specific extinction area.
Specimens (Codes) | pHRR (kW/m2) | THR (MJ/m2) | TTI (s) | pHRR/tig (s) | Residual Mass (%) | TSP (m2/kg) | TSR (m2/m2) | SEA (m2/kg) | CO Yield (g/kg) | CO2 Yield (kg/kg) | LOI | UL-94 | Citations |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
AcF20 (2 mm) | 285.7 | 19.6 | 30 | - | 35.5 | - | - | - | 0.04 | 1.68 | - | - | |
AcF40 (4 mm) | 280.4 | 39.9 | 49 | - | 28.2 | - | - | - | 0.10 | 1.50 | - | - | |
AcF3 (3 plies) | 161.3 | 4.5 | 9 | - | 26.1 | - | - | - | 0.51 | 1.29 | - | - | |
AcF5 (5 plies) | 162.0 | 13.2 | 17 | - | 35.0 | - | - | - | 0.36 | 1.49 | - | - | [1] |
AcF7 (7 plies) | 144.0 | 15.5 | 24 | - | 39.0 | - | - | - | 0.65 | 1.16 | - | - | |
AcF8 (8 plies) | 169.4 | 11.1 | 27 | - | 28.9 | - | - | - | 0.21 | 1.19 | - | - | |
AcF9 (9 plies) | 175.3 | 15.9 | 31 | - | 17.2 | - | - | - | 0.47 | 1.63 | - | - | |
Cotton | 100 | 10.0 | 22 | 73 | 0.0 | 2.2 | - | - | - | - | - | ||
Cotton4/alginat1 | 89 | 9.40 | 28 | 86 | 2.7 | 0.2 | - | - | - | - | - | ||
Cotton5/alginat5 | 68 | 7.20 | 42 | 87 | 8.4 | 0.2 | - | - | - | - | - | [18] | |
Cotton1/alginat4 | 46 | 9.70 | 71 | 97 | 10.4 | 1.9 | - | - | - | - | - | ||
Alginate | 49 | 3.50 | 103 | 123 | 23.9 | 0.9 | - | - | - | - | - | ||
PP | 1620 | 110 | 24 | - | - | - | 980 | - | 36.6 | 3.16 | - | - | |
PP/MWNT | 931 | 102 | 17 | - | - | - | 1310 | - | 44.2 | 2.89 | - | - | |
PB | 1420 | 111 | 35 | - | - | - | 1090 | - | 36.4 | 3.01 | - | - | [3] |
PB/MWNT | 830 | 108 | 18 | - | - | - | 1545 | - | 40.5 | 2.90 | - | - | |
PE | 1700 | 125 | 39 | - | - | - | 1075 | - | 30.3 | 3.36 | - | - | |
PE/MWNT | 920 | 111 | 37 | - | - | - | 1315 | - | 35.1 | 3.14 | - | - |
TSP: total smoke production, TSR: total smoke release, SEA: specific extinction area.
Specimens (Codes) | pHRR (kW/m2) | THR (MJ/m2) | TTI (s) | pHRR/tig (s) | Residual Mass (%) | TSP (m2/k) | TSR (m2/m2) | SEA (m2/k) | CO Yield (kg/kg) | CO2 Yield (kg/kg) | LOI | UL94 | Citations |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
GRPBT | 417 | 53.6 | 49 | - | 35.5 | 354 | - | 520 | 0.052 | 1.64 | - | - | |
GRPBT/AHP | 121 | 40.5 | 30 | - | 28.2 | 222 | - | 388 | 0.144 | 1.15 | - | - | [4] |
GRPBT/LHP | 105 | 43.7 | 36 | - | 26.1 | 320 | - | 475 | 0.128 | 1.52 | - | - | |
GRPBT/CHP | 101 | 42.8 | 38 | - | 35.0 | 198 | - | 249 | 0.122 | 1.42 | - | - | |
PPO | 467 | 110 | 97 | - | 26 | - | 1303 | - | 0.14 | - | 29 | V-0 | |
PPO-30AlPi | 130 | 102 | 125 | - | 52 | - | 1994 | - | 0.18 | - | 43 | V-0 | |
TPU | 613 | 111 | 84 | - | 6 | - | 1229 | - | 0.04 | - | 24 | HB | |
TPU-30AlPi | 447 | 108 | 70 | - | 13 | - | 3029 | - | 0.16 | - | 24 | V-0 | [60] |
PP | 480 | 125 | 66 | - | 2 | - | 1305 | - | 0.04 | - | 17 | HB | |
PP-30AlPi | 524 | 111 | 73 | - | 10 | - | 2310 | - | 0.16 | - | 27 | HB | |
EP | 1063 | 76.1 | 59 | 130 | 11.9 | 71.4 | - | - | - | - | 26.2 | NR | |
EP/10APP | 754 | 42.8 | 63 | 105 | 45.7 | 30.6 | - | - | - | - | 30.2 | NR | [110] |
EP/7.5APP/2.5BPOPA | 576 | 42.6 | 61 | 100 | 47.2 | 25.9 | - | - | - | - | 33.1 | V-0 | |
EP | 1063 | 114 | 76 | - | 3 | - | 3626 | 829 | - | - | HB | ||
20HS | 729 | 106 | 63 | - | 3 | - | 2768 | 636 | - | - | HB | ||
20LHP | 166 | 37 | 59 | - | 50 | - | 1016 | 459 | - | - | HB | [111] | |
15HS/5LHP | 577 | 80 | 57 | - | 13 | - | 2441 | 624 | - | - | HB | ||
5HS/15LHP | 169 | 35 | 59 | - | 54 | - | 899 | 435 | - | - | HB |
TSP: total smoke production, TSR: total smoke release SEA: specific extinction area.
Samples | pHRR (kW/m2) | THR (MJ/m2) | TTI (s) | pHRR/tig (s) | Residual Mass (%) | TSP (m2/kg) | TSR (m2/m2) | SEA (m2/kg) | CO Yield (g/kg) | CO2 Yield (kg/g) | LOI | UL-94 | Citations |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
GF30-PBT | 345 | 118 | 30 | 105 | 35.5 | - | 3987 | - | - | - | 20.0 | NR | |
GF30-PBT10 | 136 | 82 | 49 | 65 | 28.2 | - | 3958 | - | - | - | 23.2 | NR | |
GF30-PBT15 | 113 | 74 | 9 | 60 | 26.1 | - | 3548 | - | - | - | 27.0 | V-0 | [59] |
GF30-PBT20 | 107 | 75 | 17 | 60 | 35.0 | - | 2747 | - | - | - | 28.5 | V-0 | |
GF30-PBT25 | 105 | 71 | 24 | 60 | 39.0 | - | 2101 | - | - | - | 32.5 | V-0 | |
Neat Furan | 682 | 30.9 | 98 | - | 44.0 | - | 117 | - | 0.0203 | 1.37 | - | - | |
F/AS-40 amino | 554 | 24.4 | 103 | - | 50.5 | - | 109 | - | 0.0249 | 1.42 | - | - | |
F/AS-40 isocy | 556 | 30.7 | 104 | - | 50.9 | - | 108 | - | 0.0277 | 1.41 | - | - | [108] |
F/PT-40AS isocy | 507 | 23.8 | 100 | - | 49.7 | - | 96 | - | 0.0241 | 1.30 | - | - | |
F/PT-40AS amino | 569 | 26.9 | 95 | - | 50.2 | - | 92 | - | 0.0239 | 1.31 | - | - |
TSP: total smoke production, TSR: total smoke release SEA: specific extinction area.
Furthermore, the remarkable decreased smoke and toxic gas release revealed by the alternating composite in the cause of the combustion process is extremely important to reduce the harm to people in case of fires.
In order to improve the fire behaviour of the polyester resin, different phosphate fire retardants, ammonium polyphosphate (APP), silane-coated ammonium polyphosphate (S-APP), and melamine pyrophosphate (MPP) were dispersed within the resin.
This review has successfully explored the application of the various classes of the thermal and combustion state-of-the-art facilities deployed for the evaluation of the flammability and thermal stability of polymer composites.
Summarily, the small-scale facilities (such as TGA, MCC, etc.) provide detailed understanding and mastery of the thermal reaction properties of the composites. While with the medium scale, extended fire reaction parameters, which are the key indicators of the fire safety performance such as the pHRR, THR, TTI, TSP, CO/CO 2, etc. can be determined.
Furthermore, novel polymer composite materials, particularly from bio-sources (because of their environmental friendliness, economic concerns, and acceptable fire safety performance) could be designed and tested as a potential substitute for synthetic composites in the transportation sector.
In finality, this paper seeks to provide a new perspective that will encourage more research efforts in this scientific domain, especially at the large scale.
This entry is adapted from the peer-reviewed paper 10.3390/en14217070