FLAME-RETARDED THERMOPLASTIC POLYURETHANE

Abstract

A composition contains a thermoplastic polyurethane, a first flame retardant (F1) selected from ammonium phosphate and ammonium polyphosphates, and a phosphorus-containing flame retardant (F2) selected from derivatives of phosphinic acid, derivatives of phosphonic acid, and derivatives of phosphoric acid. The composition according to the present invention is useful for the production of cable sheathings.

Claims

1-14. (canceled)

15: A composition, comprising: (i) a thermoplastic polyurethane, (ii) a first flame retardant (F1), which is an ammonium polyphosphate with an average molecular weight in a range of from 20,000 Da to 150,000 Da, wherein the first flame retardant (F1) has a particle size (d50) in a range from 0.1 to 100 μm, and (iii) a phosphorus-containing flame retardant (F2) selected from the group consisting of a derivative of phosphinic acid, a derivative of phosphonic acid, and a derivative of phosphoric acid.

16: The composition according to claim 15, wherein the first flame retardant (F1) is has a coating.

17: The composition according to claim 15, wherein the first flame retardant (F1) has a solubility in a range of from 0.0001 to 1.0 g/l.

18: The composition according to claim 15, wherein the phosphorus-containing flame retardant (F2) is the derivative of phosphinic acid.

19: The composition according to claim 15, wherein the composition comprises a further phosphorus-containing flame retardant (F3), which is a derivative of phosphoric acid.

20: The composition according to claim 15, wherein a proportion of a sum of the first flame retardant (F1) and the phosphorus-containing flame retardant (F2) in the composition is in a range from 2% to 50% by weight, based on a total composition.

21: The composition according to claim 15, wherein a proportion of the first flame retardant (F1) is in a range from 1% to 40% by weight, based on an overall composition.

22: The composition according to claim 15, wherein a proportion of the phosphorus-containing flame retardant (F2) in the composition is in a range from 2% to 25% by weight, based on an overall composition.

23: The composition according to claim 19, wherein a proportion of the further phosphorus-containing flame retardant (F3) in the composition is in a range from 1% to 30% by weight, based on an overall composition.

24: The composition according to claim 15, wherein the thermoplastic polyurethane has an average molecular weight (Mw) in a range from 60,000 to 500,000 Da.

25: The composition according to claim 15, wherein a proportion of the thermoplastic polyurethane in the composition is in a range from 50% to 95% by weight, based on a total composition.

26: A method, comprising: producing a cable sheathing with the composition according to claim 15.

Description

EXAMPLES

[0171] The examples show that the properties are comparable for the inventive mixtures and common flame-retardant TPU based on melamine cyanurate. The inventive mixtures have the advantage of a low corrosivity and a low smoke toxicity and appear more transparent.

1. Example 1 (Starting Materials)

[0172] Elastollan 1185A10: TPU of Shore hardness 85 A from BASF Polyurethanes GmbH, Elastogranstrasse 60, 49448 Lemforde, based on polytetrahydrofuran polyol (PTHF) having a molecular weight of 1000, butane-1,4-diol, MDI.

[0173] Melapur MC 15 ED: Melamine cyanurate (1,3,5-triazine-2,4,6(1H,3H,5H)-trione, compound with 1,3,5-triazine-2,4,6-triamine (1:1)), CAS #: 37640-57-6, BASF SE, 67056 Ludwigshafen, GERMANY, particle size D99%<1=50 μm, D50%<=4.5 μm, water content % (w/w)<0.2.

[0174] Melapur 200/70: Melaminpolyphosphat (nitrogen content 42-44 wt %, phosphorous content 12-14 wt %)), CAS #: 218768-84-4, BASF SE, 67056 Ludwigshafen, GERMANY, particle size D99%</=70 μm, average particle size D50%<=10 μm, water content % (w/w)<0.3.

[0175] Fyrolflex RDP: Resorcinol bis(diphenylphosphate), CAS #: 125997-21-9, Supresta Netherlands B.V., Office Park De Hoef, Hoefseweg 1, 3821 AE Amersfoort, the Netherlands, phosphorous content 10.7%, viscosity at 25° C.=700 mPas, acid number<0.1 mg KOH/g, water content % (w/w)<0.1.

[0176] Exolit OP 1230: Aluminum diethylphosphinate, CAS #: 225789-38-8, Clariant Produkte (Deutschland) GmbH, Chemiepark Knapsack, 50351 Hurth, average particle size D50%=20-40 μm, water content % (w/w)<0.2.

[0177] Exolit AP 423: Ammoniumpolyphosphate, CAS #: 68333-79-9, Clariant Produkte (Deutschland) GmbH, Chemiepark Knapsack, 50351 Hurth, phosphorus content % (w/w) about 31-32 (photometry after oxidizing dissolution); nitrogen content (% wt) about 14-15 (elemental analysis), viscosity @ 25° C. (10% aqueous suspension)<100 mPas; pH value (5.0-7.5) (potentiometry in 10% aqueous suspension); decomposition temperature, initial evolution of ammonia >275° C.; average particle size, d50=8 μm; bulk density; 0.7 g/cm3, solubility in water (% w/w)<1.0; gravimetry after filtration of a 10% aqueous suspension at 25° C., water content % (w/w)<0.5

[0178] FR Cross 486: Ammoniumpolyphosphate (phase II) with coating (3-Aminopropyltriethoxysilan, CAS 919-30-2), CAS #: 68333-79-9, Budenheim Ibérica S.L.U., Extramuros, s/n, 50784 La Zaida ES, P2O5 content % (w/w) about 72; nitrogen content (% wt) about 14, pH value (6.0-7.5); decomposition temperature >250° C.; average particle size, d50=18 μm; bulk density; 600 g/l, solubility in water (0.1 g/100 cm3)<0.1.

[0179] Budit 383: Ammoniumpolyphosphate (phase II) with coating, CAS #: 68333-79-9, Budenheim Ibérica S.L.U., Extramuros, s/n, 50784 La Zaida ES, P2O5 content % (w/w) about 68; nitrogen content (% wt) about 18, pH value (approx. 7.5); decomposition temperature >300° C.; average particle size, d50=20 μm; solubility in water (0.1 g/100 cm3)<0.1.

2. Example 2 (Compositions)

[0180] The tables below list compositions in which the parts by weight (PW) of the individual starting materials have been stated. In each case, the mixtures were produced in a ZE 40 A twin-screw extruder from Berstorff with screw length of 35 D, divided into 10 barrel sections. Granules were obtained using an underwater pelletizing unit of Gala.

TABLE-US-00001 TABLE 1 1 (CE) 2 (CE) 3(IE) 4 (IE) 5 (IE) Elastollan 1185A10 70 55 70 70 70 Exolit OP 1230 30 10 20 20 20 Melapur MC 15 ED 30 Melapur 200/70 15 Fyrolflex RDP 5 Exolit AP 423 10 FR Cross 486 10 Budit 383 10

TABLE-US-00002 TABLE 2 6 7 8 9 10 11 12 13 14 (CE) (IE) (IE) (IE) (IE) (IE) (IE) (IE) (IE) Elastollan 1185A10 67.5 85 85 73 73 73 70 70 70 Fyrolflex RDP 7.5 5 5 5 5 5 5 Exolit OP 1230 10 10 2 2 2 15 15 15 Melapur MC 15 ED 25 Exolit AP 423 5 20 10 FR Cross 486 5 20 10 Budit 383 20 10

3. Example 3 (Mechanical Performance)

[0181] The mixtures were extruded with an Arenz single-screw extruder having a three-zone screw with a mixing section (screw ratio 1:3) to give films having a thickness of 1.6 mm.

[0182] Density, Shore hardness, tensile strength, tear propagation resistance, abrasion and elongation at break of the corresponding test specimens were measured. All compositions have good mechanical properties. The results are compiled in Table 3 and Table 4.

TABLE-US-00003 TABLE 3 1 2 3 4 5 (CE) (CE) (IE) (IE) (IE) Density [g/cm.sup.3] DIN EN ISO 1183-1, A 1.26 1.25 1.21 1.21 1.21 Shore [D] DIN ISO 7619-1 93 91 91 91 91 hardness Tensile [MPa] DIN EN ISO 527 11 17 15 14 17 strength Elongation [%] DIN EN ISO 527 490 550 570 580 590 at break Tear [kN/m] DIN ISO 34-1, B (b 53 55 49 44 52 strength Abrasion [mm.sup.3] DIN ISO 4649 170 80 130 145 110 Extrusion good very good good good processing good

TABLE-US-00004 TABLE 4 a 6 7 8 9 10 (CE) (IE) (IE) (IE) (IE) Density [g/cm.sup.3] DIN EN ISO 1183-1, A 1.23 1.17 1.17 1.23 1.23 Shore [D] DIN ISO 7619-1 89 86 84 88 87 hardness Tensile [MPa] DIN EN ISO 527 34 23 22 30 32 strength Elongation [%] DIN EN ISO 527 590 620 590 660 650 at break Tear [kN/m] DIN ISO 34-1, B (b 60 48 47 50 49 strength Abrasion [mm.sup.3] DIN ISO 4649 40 82 91 80 75 Extrusion very good good very very processing good good good b 11 12 13 14 (IE) (IE) (IE) (IE) Density [g/cm.sup.3] DIN EN ISO 1183-1, A 1.23 1.23 1.23 1.23 Shore [D] DIN ISO 7619-1 88 87 85 86 hardness Tensile [MPa] DIN EN ISO 527 34 14 14 17 strength Elongation [%] DIN EN ISO 527 670 630 630 640 at break Tear [kN/m] DIN ISO 34-1, B (b 52 42 39 44 strength Abrasion [mm.sup.3] DIN ISO 4649 72 65 72 62 Extrusion very very very very processing good good good good

4. Example 4 (Flame Retardancy)

[0183] In order to evaluate flame retardancy, a test specimen of thickness 5 mm is tested horizontally with radiation of intensity 35 kW/m.sup.2 in a cone calorimeter in accordance with ISO 5660 part 1 and part 2 (2002-12). The test specimens for the cone measurements with dimensions 100×100×5 mm were injection molded using an Arburg 520 with screw diameter 30 mm. The key parameters for the cone measurements for the different materials are given in Table 5 and Table 6. The inventive examples show similar THE and PH RR in comparison to the comparative examples.

TABLE-US-00005 TABLE 5 1 2 3 4 5 (CE) (CE) (IE) (IE) (IE) Total Heat [MJ/m.sup.2] 135 128 151 153 150 Release (THR) Peak of heat [kW/m.sup.2] 210 265 237 255 235 release (PHRR) Time to ignition [s] 65 60 58 54 59 Initial mass [g] 67.0 63.8 64.8 64.9 64.9 Total mass loss [g] 52.8 52.2 52.7 52.2 52.5

TABLE-US-00006 TABLE 6 6 7 8 9 10 11 12 13 14 (CE) (IE) (IE) (IE) (IE) (IE) (IE) (IE) (IE) Total Heat [MJ/m.sup.2] 143 139 145 133 140 138 139 142 138 Release (THR) Peak of heat [kW/m.sup.2] 450 485 435 338 378 360 356 365 349 release (PHRR) Time to ignition [s] 80 60 60 57 59 59 78 76 74 Initial mass [g] 61.9 61.9 62.4 66.0 66.0 66.0 65.0 65.0 65.0 Total mass loss [g] 55.2 56.2 55.9 50.9 50.1 50.4 54.3 53.8 54.5

5. Example 5 (Conductivity and Toxicity of the Smoke Gases)

[0184] The conductivities determined using DIN EN 60754-2 (2015) were found to be much lower for the inventive examples. Therefore, the inventive mixtures appear to be much less corrosive compared to the comparative mixtures. Also, it was found that the inventive examples form less hydrocyanic acid (HCN) during combustion than the comparative mixtures. The ITC value determined using the NF X 70-100 Part 1+2 (2006) is much smaller than found for the comparative examples. The results are given in Table 7 and Table 8.

TABLE-US-00007 TABLE 7 1 2 3 4 (CE) (IE) (IE) (IE) pH - value DIN EN 60754-2 (2015) 8.8 9.0 7.2 7.0 conductivity [μS/mm] DIN EN 60754-2 (2015) 24 48 10 11 ITC NF × 70-100 Partie 1 + 2 (2006) 32 62 23 18 HCN [mg/g) NF × 70-100 Partie 1 + 2 (2006) 11.3 25.0 7.2 6.1

TABLE-US-00008 TABLE 8 6 7 8 10 12 (CE) (IE) (IE) (IE) (IE) pH - value DIN EN 60754-2 (2015) 9.0 7.0 7.1 8.3 6.6 conductivity [μS/mm] DIN EN 60754-2 (2015) 50 7 9 15 7 ITC NF × 70-100 Partie 1 + 2 (2006) 35 19 18 18 21 HCN [mg/g) NF × 70-100 Partie 1 + 2 (2006) 17.4 5.9 5.5 5.4 6.6

7. Method Example 1

[0185] The water solubility of the compounds used was studied. To this end, 50 g of each flame retardant was shaken with 200 g of water for 1 hour at 20° C., followed by filtering and determination of the dry residue from the filtrate.

LITERATURE CITED

[0186] EP 0 617 079 A2 [0187] WO 2006/121549 A1 [0188] WO 03/066723 A2 [0189] US 2013/0059955 A1 [0190] US 2013/0081853 A1 [0191] WO 97/00916 A1 [0192] WO 03/066723 A1 [0193] WO 2006/121549 A1 [0194] U.S. Pat. No. 4,347,334 [0195] U.S. Pat. No. 4,467,056 [0196] U.S. Pat. No. 4,514,328 [0197] U.S. Pat. No. 4,639,331 [0198] Kunststoffhandbuch, volume VII, edited by Vieweg and Höchtlen, Carl Hanser Verlag, Munich 1966 (p. 103-113) [0199] EP 0 922 552 A1 [0200] DE 101 03 424 A1 [0201] WO 2006/072461 A1