POLYAMIDES WITH PHOSPHOROUS AND AL-PHOSPHONATES

Abstract

Described herein are thermoplastic molding materials including components:

A) 10 to 98.5 wt % of a thermoplastic polyamide,
B) 1 to 20 wt % of red phosphorus,
C) 0.5 to 15 wt % of an aluminum salt of phosphonic acid,
D) 0 to 55 wt % of a fibrous or particulate filler or mixtures thereof,
E) 0 to 30 wt % of further additives,
wherein the weight percentages of the components A) to E) sum to 100%.

Claims

1. A thermoplastic molding material comprising components: A) 10 to 98.5 wt % of a thermoplastic polyamide, B) 1 to 20 wt % of red phosphorus, C) 0.5 to 15 wt % of an aluminum salt of phosphonic acid, D) 0 to 55 wt % of a fibrous or particulate filler or mixtures thereof, and E) 0 to 30 wt % of further additives, wherein the weight percentages of the components A) to E) sum to 100%.

2. The thermoplastic molding material according to claim 1, comprising the components: A) 20 to 97.5 wt % of the thermoplastic polyamide, B) 1 to 10 wt % of the red phosphorus, C) 0.5 to 15 wt % of the aluminum salt of phosphonic acid, D) 1 to 50 wt % of the fibrous or particulate filler or mixtures thereof, E) 0 to 25 wt % of the further additives, wherein the weight percentages of the components A) to E) sum to 100%.

3. The thermoplastic molding material according to claim 1 in which the component C) is constructed from
[Al2(HPO.sub.3).sub.3.x(H.sub.2O)q  (formula I) where q is in the range of 0 to 4 or
Al.sub.2M.sub.a(HPO.sub.3).sub.b(OH).sub.cx(H.sub.2O).sub.d  (formula II) where M represents alkali metal ions a is in the range of 0.01 to 1.5 b is in the range of 2.63 to 3.5 c is in the range of 0 to 2 d is in the range of 0 to 4 or
Al.sub.2(HPO.sub.3).sub.e(H.sub.2PO.sub.3).sub.fx(H.sub.2O).sub.g  (formula III) where e is in the range of 2 to 2.99 f is in the range of 2 to 0.01 g is in the range of 0 to 4 or
mixtures of aluminum phosphites and aluminum oxide of the type Al.sub.2(HPO.sub.3).sub.3 x 0.1 to 30 Al.sub.2O.sub.3 x 0 to 50 H.sub.2O  (formula IV)
or
primary aluminum phosphonate[Al(H.sub.2PO.sub.3).sub.3]  (formula V)
or
basic aluminum phosphonate[Al(OH)H.sub.2PO.sub.3)x.2H.sub.2O]  (formula VI) or mixtures thereof

4. The thermoplastic molding material according to claim 1 containing as the component C) compounds of formula II in which M represents at least one of sodium and potassium.

5. The thermoplastic molding material according to claim 1 in which the component C) is constructed from
secondary aluminum phosphonate[Al2(HPO.sub.3).sub.3]  (formula Ia)
or
aluminum phosphonate tetrahydrate[Al.sub.2(HPO.sub.3).sub.3.4H.sub.2O]  (formula Ib) or mixtures thereof

6. The thermoplastic molding material according to claim 1 in which the component C) is constructed from mixtures of aluminum phosphites and aluminum oxide of the type Al.sub.2(HPO.sub.3).sub.3 x 0.2 to 20 Al.sub.2O.sub.3*0 to 50 H.sub.2O (formula IV).

7. The thermoplastic molding material according to claim 1 in which the component C) is constructed from compounds of formula II in which a is in the range of 0.15 to 0.4 and b is in the range of 2.80 to 3 and c is in the range of 0.01 to 0.1.

8. The thermoplastic molding material according to claim 1 in which the component C) is selected from compounds of formula III in which e is in the range of 2.834 to 2.99 and f is in the range of 0.332 to 0.03 and g is in the range of 0.01 to 0.1.

9. A method for producing fibers, films, and moldings, the method comprising using the thermoplastic molding material according to claim 1 for the production of fibers, films and moldings.

10. A fiber, film or molding obtainable from the thermoplastic molding material according to claim 1.

Description

EXAMPLES

[0158] The following components were used:

[0159] Component A1:

[0160] Polyamide 66 having an intrinsic viscosity IV of 150 ml/g, measured as a 0.5 wt % solution in 96 wt % sulfuric acid at 25° C. according to ISO 307 (Ultramid® A27 from BASF SE was employed.)

[0161] Component B:

[0162] 50% concentrate of red phosphorus having an average particle size (d50) of 10 to 30 μm in an olefin polymer E1):

[0163] 59.8 wt % ethylene, 35 wt % n-butyl acrylate, 4.5 wt % acrylic acid and 0.7 wt % maleic anhydride having a melt index MFI (190/2.16) of 10 g/10 min.

[0164] The copolymer was produced by copolymerization of the monomer at elevated temperature and elevated pressure.

[0165] Component C:

[0166] Aluminum salt of phosphonic acid (produced according to WO 2013/083247 A1, example 4) Aluminum phosphite of formula (II):

[0167] 2958 g of water are initially charged into a 16 l high-pressure stirred vessel, heated to 155° C. and stirred. 3362 g of the aluminum sulfate solution and 2780 g of sodium phosphite solution are then added simultaneously over 30 min. The resulting suspension is discharged and at 80° C. filtered, washed with hot water, redispersed and washed once again. The filtercake was dried in a dryer at 220° C. An alkali metal-aluminum mixed phosphite according to the invention having very high thermal stability was obtained in 85% yield. By atomic spectrometry the reaction product comprises 18.3% Al, 32.0% P, 0.3% S and 0.07% Na. The residual moisture content of 0.1% water was determined by Karl-Fischer titration.

[0168] Component C1V:

[0169] Aluminum diethylphosphinate (Exolit® OP1230 from Clariant Produkte GmbH).

[0170] Component D:

[0171] Standard chopped glass fibers for polyamides, length=4.5 mm, diameter=10 μm

[0172] Component E2:

[0173] In all examples in each case

[0174] 0.35 wt % Irganox® 1098 and

[0175] 0.55 wt % commercially available calcium stearate as lubricant and

[0176] 0.70 wt % of commercially available zinc oxide

[0177] Component E3:

[0178] 30% concentrate of a gas black having a specific BET surface area (measured according to DIN 66131) of 180 m.sup.2/g in polyamide 6.

[0179] Production of Molding Materials

[0180] To demonstrate the improvements described according to the invention corresponding plastic molding materials were manufactured by compounding. The individual components were mixed in a twin-screw extruder (Berstorff ZSK 26) at a throughput of 20 kg/h and about 270° C. at a flat temperature profile, discharged as a strand, cooled until pelletizable and pelletized.

[0181] The test specimens for the investigation set out in table 1 were injection molded on an Arburg 420C injection molding machine at a melt temperature of about 270° C. and a mold temperature of about 80° C.

[0182] The test specimens for the stress tests were produced according to ISO 527-2:/1993 and the test specimens for the impact strength measurements were produced according to ISO 179-2/1 eA.

[0183] The MVR measurements were performed according to ISO 1133.

[0184] The flame retardancy of the molding materials was on the one hand determined by the UL94-V method (Underwriters Laboratories Inc. Standard of Safety, “Test for Flammability of Plastic Materials for Parts in Devices and Appliances”, p. 14 to p. 18, Northbrook 1998).

[0185] The glow wire resistance GWFI (glow wire flammability index) on sheets was performed according to IEC 60695-2-12. The GWFI is a general suitability test for plastics in contact with voltage-conducting parts. The highest temperature at which one of the following conditions has been met in 3 consecutive tests was determined: (a) no ignition of the sample or (b) afterburn time or afterglow time 30 s after termination of the glow wire exposure time and no ignition of the sub-strate.

[0186] The proportions of the components A) to E) in table 1 sum to 100 wt %.

TABLE-US-00003 TABLE 1 C1 #6842 (405694 C2 C3 Ex1 Ex2 Ex3 Components (wt %) 67J0) #8048 #8179 #5212 #5074 #2268 A 60.4 57.4 49.73 57.4 50.2 46.87 B + E1 12 12 10.2 10.2 E1 6 6 D 26 26 26 26 36 36 C 9 3 3 2 2 C1V 13.67 E2 1.6 1.6 1.6 1.6 1.6 1.6 E3 3.33 Analytical results Viscosity number/[cm3/g] 154 159 158 145 — — Elastic modulus/[MPa] 8325 8415 8190 8454 11154 11675 Tensile stress at break/ 137 117 120 136 158 162 [MPa] Elongation at break/[%] 3.5 3.2 3.0 3.4 3.1 2.9 Charpy impact strength/ 69 57 57 70 78 74 [kJ/m2] Charpy notched impact 8.2 7.0 6.8 7.7 — — strength/[kJ/m2] MVR 275° C./5 kg/ 30 26 14 29 18 20 [cm3/10 min] UL94/0.8 mm V-0 n.c. n.c. V-0 V-0 V-0 UL94/1.6 mm V-0 n.c. n.c. V-0 V-0 V-0 GWFI960/1.0 mm - met not met not met met met met burn times on 3 test 58/57/55 >60/>60/>60 >60/>60/>60 39/38/47 39/38/47 39/38/47 speciments/sec C1 to C3: Comparative examples Ex 1 to Ex 3: inventive examples

[0187] It is apparent from the data of table 1 that the inventive, synergistic composition exhibits mark-edly shorter burn times in the glow wire test compared to the prior art—especially for thin wall thicknesses.