Table 2.
Flame retardant PP materials containing nitrogen-based (N) flame retardants. Data are extracted from the literature: cone calorimetry parameters (TTI, pHRR, THR), LOI, and UL-94 values. The FRI values were calculated by authors of the present review. The name and the percentage of flame retardants are provided in separate columns. “wt.%” was used for loading level of additives, while “―” stands for the systems free of additive or the neat PP. * FR means flame retardant. Since all comparisons were made in terms of FRI, classification of polymers in terms of their flame-retardant properties was not surveyed based on the chemistry of additives, heat flux, sample thickness, etc.
| PP Containing Nitrogen-Based (N) FR * | wt.% | TTI (s) |
pHRR (kW·m−2) |
THR (MJ·m−2) |
Irradiance (kW·m−2) |
Sample Thickness (mm) | FRI | LOI | UL-94 | Ref. |
|---|---|---|---|---|---|---|---|---|---|---|
| ― | 44 | 1175 | 106 | 35 | 3 | ― | ― | ― | [63] | |
| Melamine phosphate (MP) | 40 | 39 | 296 | 78 | 35 | 3 | 4.78 | ― | ― | [63] |
| ― | 54 | 930 | 140 | 35 | 4 | ― | ― | NR | [64] | |
| Melamine salt of pentaerythritol phosphate kaolinite (MPPK) | 15 | 30 | 208 | 70 | 35 | 4 | 4.96 | ― | NR | [64] |
| MPPK | 20 | 28 | 148 | 42 | 35 | 4 | 10.86 | ― | V-0 | [64] |
| MPPK | 25 | 34 | 130 | 33 | 35 | 4 | 19.10 | ― | V-0 | [64] |
| ― | 30 | 929 | 134 | 50 | 3 | ― | 17 | NR | [65] | |
| Melamine salt of tripentaerythriol phosphate (MTP) | 15 | 22 | 480 | 101 | 50 | 3 | 1.88 | ― | ― | [65] |
| MTP | 20 | 22 | 267 | 91 | 50 | 3 | 3.75 | 28 | V-1 | [65] |
| MTP | 25 | 22 | 226 | 73 | 50 | 3 | 5.53 | 32 | V-0 | [65] |
| MTP | 30 | 22 | 219 | 72 | 50 | 3 | 5.78 | 35 | V-0 | [65] |
| Methyl hydrogen siloxane modified MTP (m-MTP) | 30 | 21 | 253 | 72 | 50 | 3 | 4.78 | 30 | V-0 | [65] |
| ― | 65 | 1417 | 128.5 | 35 | 3 | ― | ― | NR | [57] | |
| Melamine pyrophosphate (MPyP) | 30 | 36 | 437 | 103.1 | 35 | 3 | 2.23 | ― | NR | [57] |
| ― | 34 | 1727 | 112 | 35 | 3 | ― | 17 | NR | [66] | |
| MPyP | 30 | 19 | 511 | 83 | 35 | 3 | 2.54 | 25.5 | NR | [66] |
| Triazine-based charring foaming agent: synthesized by reaction of cyanuric chloride and ethanolamine and ethylenediamine (TA-CFA) | 30 | 13 | 584 | 96 | 35 | 3 | 1.31 | 24 | NR | [66] |
| ― | 48 | 988 | 88.3 | 35 | 3 | ― | 17 | NR | [39] | |
| Triazine-based CFA: synthesized by reaction of cyanuric chloride and piperazine (TA-CFA) | 30 | 34 | 468 | 86.6 | 35 | 3 | 1.52 | 20.5 | V-1 | [39] |
| ― | 50 | 1350 | 91.2 | 35 | 3 | ― | 17 | NR | [40] | |
| Triazine-based CFA: synthesized by polycondensation of 2-chloro-4,6-di-(2-hydroxyethylamino)-s-triazine (TA-CFA) | 30 | 38 | 518 | 86.7 | 35 | 3 | 2.08 | 23.5 | NR | [40] |
| ― | 45 | 759.2 | 98.8 | 35 | 3 | ― | 17 | NR | [37] | |
| Triazine-based CFA: synthesized from a macromolecular triazine derivative containing hydroxyethylamino and triazine rings and ethylenediamino groups (TA-CFA) | 25 | 34 | 487.4 | 91.6 | 35 | 3 | 1.26 | 21.9 | NR | [37] |
| ― | 20 | 809 | 96 | 50 | 3 | ― | 17.6 | NR | [32] | |
| Triazine-based CFA: Poly[N4-bis(ethylenediamino)-phenyl phosphonic-N2, N6-bis(ethylenediamino)-1,3,5-triazine-N-phenyl (TA-CFA) | 25 | 12 | 529 | 88 | 50 | 3 | 1.00 | 20.6 | NR | [32] |
| ― | 18 | 1457 | 156 | 50 | 3 | ― | 19 | NR | [29] | |
| Triazin-based CA—Zinc oxide (TA-CA-ZnO) | 25 | 17 | 694 | 149 | 50 | 3 | 2.07 | 18.3 | NR | [29] |
| ― | 41 | 840.3 | 115.7 | 35 | 3 | ― | 16.4 | NR | [67] | |
| Triazin-based CA: Poly(ethanediamine-1,3,5-triazine-p-4-amino-2,2,6,6-tetramethylpiperidine) (TA-CA) | 25 | 30 | 684 | 106.7 | 35 | 3 | 0.97 | 17.8 | NR | [67] |
| ― | 48 | 1351 | 107 | 35 | 3.2 | ― | 18.5 | NR | [27] | |
| Triazin-based CA: compound containing pentaerythritol and triazine structure (TA-CA) | 20 | 42 | 994 | 98 | 35 | 3.2 | 1.29 | 22 | NR | [27] |
| ― | 66 | 633 | 44.2 | 35 | 3 | ― | 17 | NR | [23] | |
|
Triazin-based CA: synthesized by
reaction of tris (2-hydrooxyethyl) isocyanurate and 2-carboxyethyl (phenyl) phosphinic acid (TA-CA) |
20 | 31 | 417 | 37.6 | 35 | 3 | 0.83 | 22 | NR | [23] |
| ― | 31 | 1239 | 123.6 | 50 | 3 | ― | 18.5 | NR | [68] | |
|
Triazin-based IFR: synthesized by
reaction of tris(2-hydroxyethyl) isocyanurate and polyphosphoric acid and melamine (TA-IFR) |
20 | 18 | 289.9 | 89 | 50 | 3 | 3.44 | 29.3 | V-0 | [68] |
| ― | 48 | 988 | 88.3 | 35 | 3.2 | ― | 17 | NR | [31] | |
|
Triazin-based IFR: synthesized by
reaction of cyanuric chloride and N-amino ethylpiperazine (TA-IFR) |
25 | 38 | 504 | 86.6 | 35 | 3.2 | 1.58 | 23 | V-1 | [31] |
| ― | 20 | 904.4 | 126.2 | 50 | 3 | ― | 18 | NR | [69] | |
|
Piperazine-based FR: synthesized by
reaction of diphenylphosphinyl chloride and piperazine (PI-FR) |
25 | 58 | 487.7 | 87.5 | 50 | 3 | 7.75 | 27 | V-0 | [69] |
| ― | 45 | 1269 | 146.4 | 50 | 3 | ― | 17.5 | NR | [70] | |
| Piperazine-based IFR: Piperazine spirocyclic phosphoramidate (PI-IFR) | 30 | 17 | 240.4 | 120.2 | 50 | 3 | 2.42 | 30.5 | V-0 | [70] |
| ― | 47 | 802 | 104 | 35 | 3 | ― | 18 | NR | [71] | |
|
Piperazine-based IFR: synthesized by
reaction of phosphorus chloride and 2,6,7-trioxa-l-phosphabicyclo[2,2,2]-octane-4-methanol and anhydrous piperazine (PI-IFR) |
20 | 36 | 275 | 78 | 35 | 3 | 2.97 | 24 | NR | [71] |
|
Piperazine-based IFR: synthesized by
reaction of phosphorus chloride and 2,6,7-trioxa-l-phosphabicyclo[2,2,2]-octane-4-methanol and anhydrous piperazine (PI-IFR) |
30 | 37 | 209 | 74 | 35 | 3 | 4.24 | 27 | NR | [71] |
|
Piperazine-based IFR: synthesized by
reaction of phosphorus chloride and 2,6,7-trioxa-l-phosphabicyclo[2,2,2]-octane-4-methanol and anhydrous piperazine (PI-IFR) |
40 | 37 | 162 | 60 | 35 | 3 | 6.75 | 29 | V-0 | [71] |
| ― | 36 | 799.3 | 170.9 | 35 | 4 | ― | 18 | NR | [72] | |
| N-alkoxy hindered amine (NOR116) | 0.5 | 44 | 738.8 | 156.5 | 35 | 4 | 1.44 | 19 | NR | [72] |
| ― | 36 | 799 | 170 | 35 | 4 | ― | 17.5 | NR | [73] | |
| NOR116 | 0.3 | 44 | 738 | 156 | 35 | 4 | 1.44 | 19.5 | NR | [73] |
| ― | 42 | 831 | 112 | 35 | 3 | ― | 18 | NR | [50] | |
| Polyurethane containing Phosphorus-based CA (PPU-CA) | 25 | 27.3 | 475 | 83 | 35 | 3 | 1.53 | 29 | NR | [50] |
| ― | 42 | 1025 | 137.7 | 35 | 4 | ― | ― | ― | [74] | |
| Nitrogen-based FR: compound containing Nitrogen (27.5.wt.%) and Phosphorus (15.6 wt.%) (N-FR) | 22 | 22 | 170 | 50.3 | 35 | 4 | 8.64 | 32 | V-1 | [74] |
| Nitrogen-based FR: compound containing Nitrogen (27.5 wt.%) and Phosphorus (15.6 wt.%) (N-FR) | 25 | 21 | 160 | 49.1 | 35 | 4 | 8.98 | 34 | V-0 | [74] |
| ― | 30 | 1093 | 108.2 | 50 | 3 | ― | 18 | NR | [75] | |
| Nitrogen-based IFR: Poly (diallyldimethylammonium) and polyphosphate polyelectrolyte complexe-based IFR (N-IFR) | 5 | 28 | 968.5 | 103.4 | 50 | 3 | 1.10 | 20.2 | NR | [75] |
| Nitrogen-based IFR: Poly (diallyldimethylammonium) and polyphosphate polyelectrolyte complexe-based IFR (N-IFR) | 10 | 25 | 626.2 | 97.1 | 50 | 3 | 1.62 | 22 | NR | [75] |
| Nitrogen-based IFR: Poly (diallyldimethylammonium) and polyphosphate polyelectrolyte complexe-based IFR (N-IFR) | 15 | 23 | 543.1 | 94.3 | 50 | 3 | 1.76 | 24.4 | NR | [75] |
| Nitrogen-based IFR: Poly (diallyldimethylammonium) and polyphosphate polyelectrolyte complexe-based IFR (N-IFR) | 20 | 21 | 443.9 | 90.1 | 50 | 3 | 2.06 | 26.3 | NR | [75] |
| Nitrogen-based IFR: Poly (diallyldimethylammonium) and polyphosphate polyelectrolyte complexe-based IFR (N-IFR) | 25 | 18 | 335.3 | 83.9 | 50 | 3 | 2.52 | 27.5 | V-2 | [75] |
| ― | 25 | 874.1 | 89.3 | 50 | 3 | ― | 18 | NR | [76] | |
| Nitrogen-based IFR: compound containing Nitrogen (23%) and Phosphorus (21%) (N-IFR) | 25 | 12 | 94.9 | 68.2 | 50 | 3 | 5.78 | 33 | V-0 | [76] |
| ― | 29 | 980 | 136 | 50 | ― | ― | 18.5 | ― | [56] | |
| Phosphorus and Nitrogene based IFR | 30 | 22 | 229 | 93 | 50 | ― | 4.74 | 36.3 | ― | [56] |