FLAME RETARDANT-STABILIZER COMBINATION FOR THERMOPLASTIC POLYMERS

Abstract

The invention provides a flame retardant-stabilizer combination for thermoplastic polymers, comprising as component A 20% to 99.7% by weight of phosphinic salt of the formula (I), (I), in which R.sub.1 and R.sub.2 are each ethyl, M is Al and m is 3; as component B 0.2% to 16% by weight of aluminium salts of ethylbutylphosphinic acid, of dibutylphosphinic acid, of ethylhexylphosphinic acid, of butylhexylphosphinic acid and/or of dihexylphosphinic acid; as component C 0.1% to 80% by weight of a salt of phosphorous acid having the general formula (II) [HP(═O)O.sub.2].sup.2−M.sup.m+(II) in which M is Zn and m is 2; as component D 0% to 80% by weight of a salt of phosphorous acid having the general formula (III) [HP(═O)O.sub.2].sup.2−.sub.3 M.sup.m+.sub.2 (III) in which M is Al and m is 3; as component E 0% to 30% by weight of a nitrogen-containing synergist and/or of a phosphorus-containing and/or nitrogen-containing flame retardant; as component F 0% to 10% by weight of an inorganic synergist selected from zinc borate, zinc stannate, boehmite and/or hydrotalcite; as component G 0% to 3% by weight of an organic phosphonite and/or a mixture of an organic phosphonite and an organic phosphite and as component H 0% to 3% by weight of an ester and/or salt of long-chain aliphatic carboxylic acids (fatty acids) typically having chain lengths of C.sub.14 to C.sub.40, where the sum total of the components is always 100% by weight.

##STR00001##

Claims

1. Flame retardant-stabilizer combination for thermoplastic polymers, comprising as component A 20% to 97.8% by weight of phosphinic salt of the formula (I) ##STR00004## in which R.sub.1 and R.sub.2 are each ethyl, M is Al and m is 3; as component B 0.2% to 16% by weight of aluminium salts of ethylbutylphosphinic acid, of dibutylphosphinic acid, of ethylhexylphosphinic acid, of butylhexylphosphinic acid and/or of dihexylphosphinic acid; as component C 1% to 80% by weight of a salt of phosphorous acid having the general formula (II)
[HP(═O)O.sub.2].sup.2−M.sup.m+  (II) in which M is Zn and m is 2; as component D 1% to 80% by weight of a salt of phosphorous acid having the general formula (III)
[HP(═O)O.sub.2].sup.2−.sub.3M.sup.m+.sub.2  (III) in which M is Al and m is 3; as component E 0% to 30% by weight of a nitrogen-containing synergist and/or of a phosphorus-containing and/or nitrogen-containing flame retardant; as component F 0% to 10% by weight of an inorganic synergist selected from zinc borate, zinc stannate, boehmite and/or hydrotalcite; as component G 0% to 3% by weight of an organic phosphonite and/or a mixture of an organic phosphonite and an organic phosphite; and as component H 0% to 3% by weight of an ester and/or salt of long-chain aliphatic carboxylic acids (fatty acids) typically having chain lengths of C.sub.14 to C.sub.40, where the sum total of the components is always 100% by weight.

2. (canceled)

3. Flame retardant-stabilizer combination according to claim 1, comprising: 20% to 97.6% by weight of component A, 0.2% to 16% by weight of component B, 1% to 50% by weight of component C, 1% to 50% by weight of component D, 0% to 30% by weight of component E, 0% to 10% by weight of component F, 0.1% to 2% by weight of component G, and 0.1% to 2% by weight of component H, where the sum total of the components is always 100% by weight.

4. (canceled)

5. Flame retardant-stabilizer combination according to claim 1, comprising: 20% to 96.6% by weight of component A, 0.2% to 16% by weight of component B, 1% to 50% by weight of component C, 1% to 50% by weight of component D, 1% to 10% by weight of component E, 0% to 10% by weight of component F, 0.1% to 2% by weight of component G, and 0.1% to 2% by weight of component H, where the sum total of the components is always 100% by weight.

6. Flame retardant-stabilizer combination according to claim 1, comprising: 20% to 96.6% by weight of component A, 0.2% to 16 by weight of component B, 1% to 50% by weight of component C, 1% to 50% by weight of component D, 0% to 10% by weight of component E, 1% to 10% by weight of component F, 0.1% to 2% by weight of component G, and 0.1% to 2% by weight of component H, where the sum total of the components is always 100% by weight.

7. Flame retardant-stabilizer combination according to claim 1, wherein component B comprises the Al salts of ethylbutylphosphinic acid, of dibutylphosphinic acid and/or of ethylhexylphosphinic acid.

8. (canceled)

9. (canceled)

10. Flame retardant-stabilizer combination according to claim 1, wherein component E comprises condensation products of melamine and/or reaction products of melamine with polyphosphoric acid and/or reaction products of condensation products of melamine with polyphosphoric acid or mixtures thereof; and/or melamine cyanurate.

11. Flame retardant-stabilizer combination according to claim 10, wherein component E comprises melem, melam, melon, dimelamine pyrophosphate, melamine polyphosphate, melem polyphosphate, melam polyphosphate, melon polyphosphate, and/or mixed polysalts thereof and/or nitrogen-containing phosphates of the formulae (NH.sub.4).sub.yH.sub.3-yPO.sub.4 or (NH.sub.4PO.sub.3).sub.z, where y is 1 to 3 and z is 1 to 10 000.

12. Use of a flame retardant-stabilizer combination according to claim 1 as flame retardant in or as flame retardant for clearcoats and intumescent coatings, in or as flame retardant for wood and other cellulosic products, in or as reactive and/or nonreactive flame retardant for polymers, for production of flame-retardant polymer moulding compounds, for production of flame-retardant polymer mouldings and/or for rendering polyester and pure and blended cellulose fabrics flame-retardant by impregnation, and/or as synergist and/or as synergist in further flame retardant mixtures.

13. Flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres comprising 2% to 50% by weight of flame retardant-stabilizer combination according to claim 1, 50% to 98% by weight of thermoplastic or thermoset polymer or mixtures thereof, 0% to 50% by weight of additives and 0% to 60% by weight of filler or reinforcing materials, where the sum of the components is 100% by weight.

14. Flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres comprising 7% to 30% by weight of flame retardant-stabilizer combination according to claim 1, 30% to 91% by weight of thermoplastic or thermoset polymer or mixtures thereof, 1% to 30% by weight of additives and 1% to 40% by weight of filler or reinforcing materials, where the sum of the components is 100% by weight.

15. Flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres comprising flame retardant mixtures according to claim 1, characterized in that the polymer comprises thermoplastic polymers of the HI (high-impact) polystyrene, polyphenylene ether, polyimide, polyester or polycarbonate type, and blends or polymer blends of the ABS (acrylonitrile-butadiene-styrene) or PC/ABS (polycarbonate/acrylonitrile-butadiene-styrene) or PPE/HIPS (polyphenylene ether/HI polystyrene) polymer type.

16. Flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres according to claim 13, wherein the additives are antioxidants, UV absorbers, light stabilizers, metal deactivators, peroxide-destroying compounds, polyamide stabilizers, basic costabilizers, nucleating agents, further flame retardants and/or other additions.

17. Flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres according to claim 13, wherein the fillers and reinforcers are calcium carbonate, silicates, glass fibres, asbestos, talc, kaolin, mica, barium sulfate, metal oxides and hydroxides, carbon black, graphite and/or other suitable substances.

18. Use of the flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres according to claim 13 in or for plug connectors, current-bearing components in power distributors (residual current protection), circuit boards, potting compounds, power connectors, circuit breakers, lamp housings, LED lamp housings, capacitor housings, coil elements, ventilators, grounding contacts, plugs, in/on printed circuit boards, housings for plugs, cables, flexible circuit boards, charging cables, motor covers, textile coatings and other products.

19. Flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres according to claim 14, wherein the additives are antioxidants, UV absorbers, light stabilizers, metal deactivators, peroxide-destroying compounds, polyamide stabilizers, basic costabilizers, nucleating agents, further flame retardants and/or other additions.

20. Flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres according to claim 14, wherein the fillers and reinforcers are calcium carbonate, silicates, glass fibres, asbestos, talc, kaolin, mica, barium sulfate, metal oxides and hydroxides, carbon black, graphite and/or other suitable substances.

21. Flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres according to claim 15, wherein the additives are antioxidants, UV absorbers, light stabilizers, metal deactivators, peroxide-destroying compounds, polyamide stabilizers, basic costabilizers, nucleating agents, further flame retardants and/or other additions.

22. Flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres according to claim 15, wherein the fillers and reinforcers are calcium carbonate, silicates, glass fibres, asbestos, talc, kaolin, mica, barium sulfate, metal oxides and hydroxides, carbon black, graphite and/or other suitable substances.

23. Flame-retardant thermoplastic or thermoset polymer moulding compound or polymer mouldings, films, filaments and/or fibres according to claim 16, wherein the fillers and reinforcers are calcium carbonate, silicates, glass fibres, asbestos, talc, kaolin, mica, barium sulfate, metal oxides and hydroxides, carbon black, graphite and/or other suitable substances.

Description

EXAMPLE 1

[0172] To an initial charge of 8763.6 g of zinc sulfate heptahydrate and 736.2 g of demineralized water was added 5235.8 g of disodium phosphite solution (39.3%) within 2 h, and then 370 g of demineralized water. The resultant zinc phosphite was crystallized at 150° C. for 5 h. Subsequently, the slurry was discharged and filtered three times in a suction filter with five times the mass of demineralized water, and the filter cake was dried at 130° C. in a drying cabinet. This results in 2096 g of product (97% yield). The x-ray powder diffractogram shows reflections at angles of 2 theta 18.2°/d value 4.86 ångström, and 20.5°/4.33 Å, 23.8°/3.75 Å, 30.3°/2.95 Å, 31.0°/2.88 Å, 32.5°/2.76 Å, 33.0°/2.72 Å.

EXAMPLE 2

[0173] The same chemical doses are used as in Example 1. The zinc phosphite was crystallized at 150° C. for 0.5 h and washed and dried as in Example 1. This results in 2090 g of product (97% yield). The x-ray powder diffractogram shows the same reflections as in Example 1.

EXAMPLE 3

[0174] The same chemical doses are used as in Example 1. The zinc phosphite was crystallized at 115° C. for 5 h and washed and dried as in Example 1. This results in 2098 g of product of composition Na.sub.2Zn.sub.3(HPO.sub.3).sub.4(97% yield).

[0175] The x-ray powder diffractogram shows reflections at angles of 2 theta 10.0°/d value 8.82 ångström, and 0.0°/4.67 Å, 20.15°/4.41 Å, 21.3°/4.17 Å, 22.8°/3.89 Å, 27.8°/3.21 Å, 28.1°/3.17 Å.

EXAMPLE 4

[0176] The same chemical doses are used as in Example 1. The zinc phosphite was crystallized at 100° C. for 1 h and washed and dried as in Example 1. This results in 2095 g of product of composition ZnHPO.sub.3*1.5H.sub.2O (97% yield).

[0177] The x-ray powder diffractogram shows reflections at angles of 2 theta 12.1°/d value 7.33 ångström, and 19.3°/4.60 Å, 22.8°/3.89 Å, 23.6°/3.77 Å.

Examples with Polymers

[0178] 1. Components used

[0179] Commercial polymers (pellets):

[0180] Nylon-6,6 (PA 6,6-GR): Ultramid® A27 (from BASF AG, Germany)

[0181] Nylon-6T/6,6: Zytel® HTN FE 8200 (from DuPont, USA) polybutylene terephthalate (PBT): Ultradur® B4500 (from BASF AG, Germany)

[0182] PPG HP 3610 EC 10 4.5 mm glass fibres (from Nippon Electric Glass, the Netherlands)

[0183] PPG HP 3786 EC 10 4.5 mm glass fibres (from Nippon Electric Glass, the Netherlands)

[0184] Flame Retardant (Component A):

[0185] aluminium diethylphosphinate, aluminium salt of diethylphosphinic acid prepared in analogy to example 1 of DE 196 07 635 A1.

[0186] Flame Retardant (Component B1):

[0187] aluminium salt of diethylphosphinic acid containing

[0188] 1.7 mol % of aluminium ethylbutylphosphinate (examples B7, B11, B15, B16, B18, B20, B22, B23, B25, B27, B28, B29) or

[0189] 1.3 mol % (B5, B13, B21, B26)

[0190] 5.3 mol % (B12)

[0191] 7.3 mol % (B6, B17)

[0192] 0.7 mol % (B8, B10, B14, B19, B24)

[0193] prepared by the process according to U.S. Pat. No. 7,420,007 B2

[0194] Flame Retardant (Component B2):

[0195] aluminium salt of diethylphosphinic acid containing

[0196] 0.7 mol % of aluminium dibutylphosphinate (B9)

[0197] 1.7 mol % of aluminium dibutylphosphinate (B22)

[0198] prepared by the process according to U.S. Pat. No. 7,420,007 B2

[0199] Flame Retardant (Component B3):

[0200] aluminium salt of diethylphosphinic acid containing

[0201] 1.7 mol % of aluminium ethylhexylphosphinate (B23)

[0202] prepared by the process according to U.S. Pat. No. 7,420,007 B2

[0203] Flame Retardant (Component C):

[0204] zinc salt of phosphorous acid, referred to hereinafter as PHOPZN

[0205] Flame Retardant (Component D):

[0206] aluminium salt of phosphorous acid, referred to hereinafter as PHOPAL

[0207] Synergist (Component E):

[0208] melamine polyphosphate (referred to as MPP), Melapur® 200 (from Ciba SC, Switzerland)

[0209] melamine cyanurate (referred to as MC), Melapur® MC50 (from Ciba SC, Switzerland)

[0210] melem, Delacal® 420, Delacal® 360 (from Delamin Ltd, UK)

[0211] Component F:

[0212] zinc borate, Firebrake® ZB and Firebrake® 500, from Borax, USA Boehmite: Apyral AOH 180, from Nabaltec, Germany

[0213] Stabilizers (Component G):

[0214] Irgafos 168/Irganox 1098 1:1 for nylon-6,6, Ultranox 626/Irganox 1076 1:1 for PBT; PEP-Q

[0215] Wax Components (Component H):

[0216] Licomont® CaV 102, Clariant Produkte (Deutschland) GmbH, Germany (Ca salt of montan wax acid)

[0217] Licowax® E, from Clariant Produkte (Deutschland) GmbH, Germany (esters of montan wax acid)

[0218] 2. Production, Processing, and Testing of Flame-Retardant Polymer Moulding Compounds

[0219] The flame retardant components were mixed with the phosphonite, lubricants, and stabilizers in the ratio specified in the table and incorporated via the side intake of a twin-screw extruder (Leistritz ZSE 27/44D) into PA 6,6 at temperatures of 260 to 310° C., and into PBT at 250-275° C. The glass fibres were added via a second side intake. The homogenized polymer strand was drawn off, cooled in a water bath, and then pelletized.

[0220] After sufficient drying, the moulding compounds were processed into test specimens on an injection-moulding machine (Arburg 320 C Allrounder) at melt temperatures of 250 to 300° C., and tested and classified for flame retardancy using the UL 94 test (Underwriter Laboratories).

[0221] The UL 94 fire classifications are as follows: [0222] V-0 afterflame time never longer than 10 sec, total of afterflame times for 10 flame applications not more than 50 sec, no flaming drops, no complete consumption of the specimen, afterglow time for specimens never longer than 30 sec after end of flame application. [0223] V-1 afterflame time never longer than 30 sec after end of flame application, total of afterflame times for 10 flame applications not more than 250 sec, afterglow time for specimens never longer than 60 sec after end of flame application, other criteria as for V-0. [0224] V-2 cotton indicator ignited by flaming drops, other criteria as for V-1.

[0225] Not classifiable (ncl): Does not conform to fire classification V-2.

[0226] D Smoke Density

[0227] Optical smoke gas density was determined according to standard ISO 5659 in an NBS smoke chamber from Fire Testing Technologies, UK. Specimens produced by injection moulding with dimensions of 75 mm×75 mm and a thickness of 2 mm. The specimens were clamped horizontally and irradiated with 25 kW/m.sup.2 in the presence of a pilot flame for 40 min. The attenuation of a light beam by the smoke is measured with a photodetector. Smoke gas density is inversely proportional to the attenuation of light.

[0228] The flowability of the moulding compounds was determined by establishing the melt volume flow rate (MVR) at 275° C./2.16 kg. A sharp rise in the MVR value indicates polymer degradation.

[0229] For comparability, all tests in the respective series, unless stated otherwise, were performed under identical conditions (temperature programs, screw geometries, injection moulding parameters, etc.).

[0230] The amounts stated in the tables which follow are parts by weight.

[0231] Table 1 shows how the addition of zinc phosphite and aluminium phosphite reduces the smoke gas density of nylon-6,6 with aluminium diethylphosphinate, aluminium butylethylphosphinate and aluminium dibutylphosphinate. PHOPZN results in a lower smoke gas density. Only the use of aluminium diethylphosphinate, aluminium butylethylphosphinate and aluminium dibutylphosphinate, PHOPZN and PHOPAL together achieves the UL 94 V-0 fire class together with a low smoke gas density.

TABLE-US-00001 TABLE 1 PA 6,6 GF 30 test results. V1-V2 are comparative examples; B5 to B11 are flame retardant-stabilizer mixtures according to the invention V1 V2 B5 B6 B7 B8 B9 B10 B11 Nylon-6,6 50 50 50 50 50 50 50 50 50 3610 glass fibres 30 30 30 30 30 30 30 30 30 A: aluminium 20 17.5 17.27 15.15 15.98 16.15 14.9 14.9 12.29 diethylphosphinate B1: aluminium 0.23 1.1 0.27 0.11 0.1 0.21 butylethylphosphinate B2: aluminium 0.1 dibutylphosphinate C: PHOPZN 2.5 2.5 2.5 2.5 2.5 2.5 5 D: PHOPAL 2.5 1.25 1.25 1.25 2.5 2.5 2.5 UL 94 0.8 mm V-1 V-0 V-1 V-0 V-0 V-0 V-0 V-0 V-0 Opt. smoke gas high high average low low low low low low density

[0232] Table 2 shows comparative examples V4 and V5 in which a flame retardant-stabilizer combination based on aluminium diethylphosphinate and aluminium butylethylphosphinate, MPP, PHOPZN or PHOPAL was used.

[0233] The results in which the flame retardant-stabilizer mixture according to the invention was used are listed in examples B12 to B15. All amounts are reported as % by weight and are based on the polymer moulding compound including the flame retardant-stabilizer combination and additives.

TABLE-US-00002 TABLE 2 PA 6,6 GF 30 test results. V2 to V4 are comparative examples; B12 to B15 are flame retardant-stabilizer mixture according to the invention V2 V4 B12 B13 B14 B15 Nylon-6,6 49.55 49.55 49.55 49.55 49.55 49.55 3610 glass fibres 30 30 30 30 30 30 A: aluminium 13 15 15 14.81 13.4 14.75 diethylphosphinate B1: aluminium 0.75 0.19 0.1 0.25 butylethylphosphinate C: PHOPZN 2 2.5 2.5 1 D: PHOPAL 2 2.5 2 3 E: MPP 7 3 3 2 1 H: Licowax E 0.25 0.25 0.25 0.25 0.25 0.25 G: 168/1098 1:1 0.20 0.20 0.20 0.20 0.20 0.20 UL 94 0.8 mm V-0 V-0 V-1 V-0 V-0 V-0 MVR 275° C./2.16 kg 19 13 12 5 9 7 Opt. smoke gas high high average low low low density

[0234] It is apparent from examples B12-15 that the mixture according to the invention of the aluminium diethylphosphinate and aluminium butylethylphosphinate, PHOPZN, PHOPAL and optionally MPP components achieves the UL 94 V-0 fire class, low MVR (little polymer degradation) and low optical smoke gas density.

TABLE-US-00003 TABLE 3 PBT GF 25 test results. V5-V6 are comparative examples; B16-B25 are flame retardant-stabilizer mixture according to the invention V5 V6 B16 B17 B18 B19 B20 B21 B22 B23 B24 B25 PBT 54.55 54.55 54.55 54.55 54.55 54.55 54.55 54.55 54.55 54.55 54.55 54.55 3786 glass fibres 25 25 25 25 25 25 25 25 25 25 25 25 A: aluminium 13 12 11.8 13.98 11.8 11.92 18.69 15.2 11.8 11.8 15.3 9.83 diethylphosphinate B1: aluminium 0.2 1.02 0.2 0.08 0.31 0.2 0.1 0.17 butylethylphosphinate B2: aluminium 0.2 dibutylphosphinate B3: aluminium 0.2 ethylhexylphosphinate C: PHOPZN 5 2.5 2 2 0.5 0.3 2 2 0.3 9 D: PHOPAL 5 2.5 2 2 0.5 0.3 2 2 0.3 E1: MC 7 3 3 4 4 1 E2: MPP 4 4 4 4 H: Licowax E 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 G: P-EPQ 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 UL 94 0.8 mm V-1 V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-1 Solution viscosity 1185 1235 1279 1375 1350 1238 1320 1290 1255 1370 1335 1235 SV* Opt. smoke gas high high average low low low average average low low average low density *in dichloroacetic acid, pure PBT (uncompounded) gives 1450

[0235] The incorporation of aluminium diethylphosphinate and MC results in a high smoke gas density and only a UL 94 V-1 fire class. The combination of aluminium diethylphosphinate, PHOPAL and MC leads to UL 94 V-0 and high smoke gas density. Only by the inventive incorporation of aluminium diethylphosphinate, aluminium butylethylphosphinate, aluminium dibutylphosphinate, aluminium ethylhexylphosphinate, PHOPZN or PHOPAL and PHOPZN, and MC or MPP, achieves a V-1N-0 fire class and reduced smoke gas density.

[0236] The inventive combination of aluminium diethylphosphinate, aluminium butylethylphosphinate, aluminium dibutylphosphinate, aluminium ethylhexylphosphinate with PHOPZN and PHOPAL and optionally the further additives additionally virtually completely suppresses polymer degradation, as discernible from the low SV number.

TABLE-US-00004 TABLE 4 PA6T/6,6 GF 30 test results. V7-V8 are comparative examples; B26-B29 are flame retardant-stabilizer mixture according to the invention V7 V8 B26 B27 B28 B29 Nylon-6T/6,6 54.55 54.55 54.55 54.55 54.55 54.55 3610 glass fibres 30 30 30 30 30 30 A: aluminium 15 13 13 12 12 12 diethylphosphinate B1: aluminium 0.2 0.2 0.2 0.2 butylethylphosphinate C: PHOPZN 2 2.5 1.5 1 D: PHOPAL 2 2.5 1.5 1 F: boehmite 2 3 H: CaV 102 0.25 0.25 0.25 0.25 0.25 0.25 G: P-EPQ 0.20 0.20 0.20 0.20 0.20 0.20 UL 94 0.8 mm V-0 V-1 V-1 V-0 V-0 V-0 Opt. smoke gas high high average low low low density

[0237] Table 4 shows that the inventive combination of aluminium diethylphosphinate, aluminium butylethylphosphinate, PHOPZN and PHOPAL achieves a V-1N-0 classification with reduced smoke gas density than without PHOPZN or the combination of PHOPZN and PHOPAL.