FLAME RETARDANT MIXTURE

Abstract

The invention relates to a mixture containing as component A at least one organic phosphinic acid salt and as component B at least one alkali metal stannate (M′.sub.2SnO.sub.3), alkali metal hydroxyl stannate (M′.sub.2Sn(OH).sub.6), alkaline earth metal stannate (M″SnO.sub.3) and/or alkaline earth metal hydroxy stannate (M″Sn(OH).sub.6). The invention relates also to the use of such a mixture.

Claims

1. A mixture containing as component A at least one organic phosphinic acid salt and as component B at least one alkali metal stannate (M′.sub.2SnO.sub.3), alkali metal hydroxyl stannate (M′.sub.2Sn(OH).sub.6), alkaline earth metal stannate (M″SnO.sub.3) and/or alkaline earth metal hydroxy stannate (M″Sn(OH).sub.6).

2. A mixture as claimed in claim 1, wherein M′ is one of Na or K and M″ is one of Mg, Ca or Ba.

3. A mixture as claimed in claim 1, wherein the at least one organic phosphinic acid salt corresponds to formula (I) ##STR00007## wherein R.sup.1, R.sup.2 are the same or different and are each H, C.sub.1-C.sub.18-alkyl, linear or branched, C.sub.6-C.sub.18-aryl, C.sub.7-C.sub.18-arylalkyl or C.sub.7-C.sub.18-alkylaryl, or R.sup.1 and R.sup.2 form one or more rings with each other, M is Mg, Ca, Al, Sb, Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K and/or a protonated nitrogen base; m is from 1 to 4.

4. A mixture as claimed in claim 1, wherein R.sup.1, R.sup.2 are the same or different and are each methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl, 2-pentyl, 3-pentyl, 2-methylbutyl, 3-methylbutyl (iso-mentyl), 3-methylbut-2-yl, 2-methylbut-2-yl, 2,2-dimethylpropyl (neopentyl), hexyl, heptyl, octyl, nonyl, decyl, cyclopentyl, cyclopentylethyl, cyclohexyl, cyclohexylethyl, phenyl, phenylethyl, methylphenyl und/oder methylphenylethyl.

5. A mixture as claimed in claim 3, wherein M is a calcium, aluminum, zinc, titanium or iron ion.

6. A mixture as claimed in claim 1, wherein component B has a surface area of 20 to 200 m.sup.2/g BET

7. A mixture as claimed in claim 1, containing 40 to 99.9% by weight of component A and 0.1 to 60% by weight of component B.

8. A mixture as claimed in claim 1, containing 70 to 99.9% by weight of component A and 0.1 to 30% by weight of component B.

9. A mixture as claimed in claim 1, containing 80 to 99% by weight of component A and 1 to 20% by weight of component B.

10. A mixture as claimed in claim 1, containing as further component C 0 to 79.9% by weight of a nitrogen-containing synergist and/or a phosphorus/nitrogen flame retardant and/or phosphorus containing synergist or flame retardant which comprises a salt of phosphorous acid having the formula (II)
[HP(═O)O.sub.2].sup.2−M′″.sup.m+  (II) in which M′″ is Mg, Ca, Al, Sb, Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na and/or K, as further component D 0 to 3% by weight of a phosphonite or of a mixture of a phosphonite and a phosphite, as further component E 0 to 3% by weight of an ester or salt of long-chain aliphatic carboxylic acids (fatty acids), which typically have chain lengths of C.sub.14 to C.sub.40, the sum of the components always being 100% by weight, and as further component F, from 0 to 20% by weight of telomeric phosphinic acid salts.

11. A mixture as claimed in claim 10, wherein the mixture comprises to 98.9% by weight of component A, 1 to 39.9% by weight of component B, 0.1 to 59% by weight of component C, 0 to 2% by weight of component D, 0 to 2% by weight of component E, and 0 to 20% by weight of component F.

12. A mixture as claimed in claim 11, wherein the mixture comprises 50 to 94.5% by weight of component A, to 39.5% by weight of component B, 0.5 to 45% by weight of component C, 0 to 2% by weight of component D, 0 to 2% by weight of component E, and 0 to 20% by weight of component F.

13. A mixture as claimed in claim 12, wherein the mixture comprises 60 to 94% by weight of component A, to 30% by weight of component B, 1 to 35% by weight of component C, 0 to 2% by weight of component D 0 to 2% by weight of component E, and 0 to 20% by weight of component F.

14. A mixture as claimed in claim 13, wherein the mixture comprises 60 to 89.7% by weight of component A, to 20% by weight of component B, to 20% by weight of component C, 0.1 to 2% by weight of component D 0.1 to 2% by weight of component E, and 0.1 to 20% by weight of component F.

15. A mixture as claimed in claim 10, wherein component C comprises reaction products of phosphorous acid with aluminum compounds.

16. A mixture as claimed in claim 10, wherein component C comprises aluminum phosphite [Al(H.sub.2PO.sub.3).sub.3], secondary aluminum phosphite [Al.sub.2(HPO.sub.3).sub.3], basic aluminum phosphite [Al(OH)(H.sub.2PO.sub.3).sub.2*2 aq], aluminum phosphite tetrahydrate [Al.sub.2(HPO.sub.3).sub.3*4 aq], aluminum phosphonate, Al.sub.7(HPO.sub.3).sub.9(OH).sub.6(1,6-hexanediamine).sub.1.5*12H.sub.2O, Al.sub.2(HPO.sub.3).sup.3*xAl.sub.2O.sub.3*nH.sub.2O with x=1-2.27 and n=1-50 and/or Al.sub.4H.sub.6P.sub.16O.sub.18, or comprises aluminum phosphites of the formulae (III), (IV) and/or (V), where formula (III) comprises: Al.sub.2(HPO.sub.3).sub.3 x (H.sub.2O).sub.q and q is 0 to 4; formula (IV) comprises Al.sub.2.00M.sub.z(HPO.sub.3).sub.y(OH).sub.vX(H.sub.2O).sub.w and M is alkali metal ions, z is 0.01 to 1.5, y is 2.63 to 3.5, v is 0 to 2, and w is 0 to 4; formula (V) comprises Al.sub.2.00(HPO.sub.3).sub.u(H.sub.2PO.sub.3).sub.t x (H.sub.2O).sub.s and u is 2 to 2.99 and t is 2 to 0.01 and s is 0 to 4, or the aluminum phosphite comprises mixtures of aluminum phosphite of the formula (III) with sparingly soluble aluminum salts and nitrogen-free foreign ions, mixtures of aluminum phosphite of the formula (IV) with aluminum salts, mixtures of aluminum phosphites of the formulae (IV) to (V) with aluminum phosphite [Al(H.sub.2PO.sub.3).sub.3], with secondary aluminum phosphite [Al.sub.2(HPO.sub.3).sub.3], with basic aluminum phosphite [Al(OH)(H.sub.2PO.sub.3).sub.22 aq], with aluminum phosphite tetrahydrate [Al.sub.2(HPO.sub.3).sub.3*4 aq], with aluminum phosphonate, with Al.sub.7(HPO.sub.3).sub.9(OH).sub.6(1,6-hexanediamine).sub.1.5*12H.sub.2O, with Al.sub.2(HPO.sub.3).sub.3*xAl.sub.2O.sub.3*nH.sub.2O with x=1-2.27 and n=1-50 and/or with Al.sub.4H.sub.6P.sub.16O.sub.18.

17. A mixture as claimed in claim 10, wherein component C 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; or comprises melem, melam, melon, dimelamine pyrophosphate, melamine polyphosphate, melem polyphosphate, melam polyphosphate, melon polyphosphate and/or mixed polysalts thereof; or comprises nitrogen-containing phosphates of the formulae (NH.sub.4).sub.y H.sub.3-y PO.sub.4 and/or (NH.sub.4PO.sub.3).sub.z, where y is 1 to 3 and z is 1 to 10000.

18. A mixture as claimed in claim 10, wherein the phosphonites (component D) are of the general structure
R—[P(OR.sub.1).sub.2].sub.m  (VI) where R is a mono- or polyvalent aliphatic, aromatic or heteroaromatic organic radical and R.sub.1 is a compound of the structure (VII) ##STR00008## or the two radicals R.sub.1 form a bridging group of the structure (VIII) ##STR00009## where A is direct bond, O, S, C.sub.1-C.sub.18-alkylene (linear or branched), C.sub.1-C.sub.18-alkylidene (linear or branched), in which R.sub.2 independently at each occurrence is C.sub.1-C.sub.12-alkyl (linear or branched), C.sub.1-C.sub.12-alkoxy and/or C.sub.5-C.sub.12-cycloalkyl, and n is 0 to 5, and m is 1 to 4.

19. A mixture as claimed in claim 10, wherein component E comprises alkali metal, alkaline earth metal, aluminum and/or zinc salts of long-chain fatty acids having 14 to 40 carbon atoms and/or reaction products of long-chain fatty acids having 14 to 40 carbon atoms with polyhydric alcohols, such as ethylene glycol, glycerol, trimethylolpropane and/or pentaerythritol.

20. A mixture as claimed in claim 10, wherein the telomeric phosphinic acid salts (component F) are metal salts of ethyl butyl phosphinic acid, dibutyl phosphinic acid, ethyl hexyl phosphinic acid, butyl hexyl phosphinic acid, ethyl octyl phosphinic acid, sec-butyl ethyl phosphinic acid, 1-ethylbutyl-butyl-phosphinic acid, ethyl-1-methylpentyl-phosphinic acid, di-sec-butyl phosphinic acid (di-1-methyl-propyl phosphinic acid), propyl-hexyl phosphinic acid, dihexyl phosphinic acid, hexyl-nonyl phosphinic acid, propyl-nonyl phosphinic acid, dinonyl phosphinic acid, dipropyl phosphinic acid, butyl-octyl phosphinic acid, hexyl-octyl phosphinic acid, dioctyl phosphinic acid, ethyl cyclopentylethyl phosphinic acid, butyl cyclopentylethyl phosphinic acid, ethyl cyclohexylethyl phosphinic acid, butyl cyclohexylethyl phosphinic acid, ethyl phenylethyl phosphinic acid, butyl phenylethyl phosphinic acid, ethyl 4-methylphenylethyl phosphinic acid, butyl 4-methylphenylethyl phosphinic acid, butyl cyclopentyl phosphinic acid, butyl cyclohexylethyl phosphinic acid, butylphenyl phosphinic acid, ethyl 4-methylphenyl phosphinic acid and/or butyl 4-methylphenyl phosphinic acid and wherein the metal is minimum one of the group Mg, Ca, Al, Sb, Sn, Ge, Ti, Fe, Zr, Zn, Ce, Bi, Sr, Mn, Li, Na and/or K.

21. The use of a mixture as claimed in claim 1 as a binder, as a crosslinker or accelerator in the curing of epoxy resins, polyurethanes or unsaturated polyester resins; as polymer stabilizers, as crop protection compositions, as sequestrants, as a mineral oil additive, as an anticorrosive, in washing and cleaning composition applications and in electronics applications.

22. The use of mixtures as claimed in claim 1 as a flame retardant, especially as a flame retardant for clearcoats and intumescent coatings, as a flame retardant for wood and other cellulosic products, as a reactive or nonreactive flame retardant for polymers, for production of flame-retardant polymer molding compositions, for production of flame-retardant polymer moldings and/or for rendering polyester and pure and blended cellulose fabrics flame-retardant by impregnation, and as a synergist.

23. A flame-retardant thermoplastic or thermoset polymer molding composition or polymer molding, film, filament, fiber or polymer shaped body comprising 0.5 to 45% by weight of mixtures as claimed in claim 1, 55 to 99.5% by weight of thermoplastic or thermoset polymer or mixtures thereof, 0 to 55% by weight of additives and 0 to 55% by weight of filler or reinforcing materials, where the sum of the components is 100% by weight.

24. A flame-retardant thermoplastic or thermoset polymer molding composition or polymer molding, film, filament, fiber or polymer shaped body comprising 1 to 30% by weight of mixtures as claimed in claim 1, 10 to 95% by weight of thermoplastic or thermoset polymer or mixtures thereof, 2 to 30% by weight of additives and 2 to 30% by weight of filler or reinforcing materials, where the sum of the components is 100% by weight.

25. A flame-retardant thermoplastic or thermoset polymer molding composition or polymer molding, film, filament, fiber or polymer shaped body as claimed in claim 23, polymer comprises polyesters, polyamides, thermoplastic elastomers, thermoplastic polyurethanes, thermoplastic polyester elastomers, styrenics, polyketones, polyolefins, polyacrylates and/or polymer blends comprising polyamides or polyesters or other blends and the thermoset polymers are based on epoxies, acrylates, vinylesters, unsaturated polyesters and/or phenolics.

26. A flame-retardant plastics molding composition, film, filament, fiber or polymer shaped body as claimed in claim 23 which comprises the flame retardant-stabilizer combination in an amount of from 10 to 30% by weight, based on the plastics molding composition.

27. A flame-retardant plastics molding composition, film, filament, fiber or polymer shaped body as claimed in claim 23 for the use in or for connectors, power wetted parts in current distributors (RCCB), boards, potting compounds, power connectors, circuit breakers, lamp housing, LED housing, condenser housing, bobbins and fans, protection contacts, connectors, in/on circuit boards, casings for connectors, cables, flexible circuit boards, charger for mobile phones, engine covers, textile coatings, moldings in the form of components for the electrical/electronics sector, in particular for parts of printed circuit boards, housings, films, cables, switches, distribution boards, relays, resistors, capacitors, coils, lamps, diodes, LEDs, transistors, connectors, controllers, memories and sensors, in the form of large-area components, in particular housing parts for cabinets and in the form of elaborately designed components with sophisticated geometry.

Description

EXAMPLES

[0163] 1. Components Used

[0164] Commercial polymers (pellets):

[0165] Polyamide 6.6 (PA 6.6-GV): Ultramid® A27 (from BASF, D)

[0166] Polyphthalamide (PPA): Vestamid® HT plus M1000 and M3000 (from Evonik, D)

[0167] Polybutylenterephthalate (PBT): Ultradur B4500 (from BASF, D)

[0168] Glass fibers, PPG HP 3610 EC 10 4.5 mm (from PPG Ind. Fiber Glass, NL)

[0169] Zinc borate Firebrake® 500, from Borax, USA

[0170] Zinc stannate Flamtard® H and Flamtard® S, from William Blythe, UK

[0171] Component A:

[0172] Aluminum salt of diethylphosphinic acid, referred to hereinafter as DEPAL1

[0173] Component A with Component F:

[0174] Aluminum salt of diethylphosphinic acid with 0.1% Telomers, referred to hereinafter as DEPAL2

[0175] Aluminum salt of diethylphosphinic acid with 2.5% Telomers, referred to hereinafter as DEPAL3

[0176] Component B:

[0177] Calcium stannate from William Blythe, UK,

[0178] Magnesium stannate

[0179] Barium stannate

[0180] Component C:

[0181] Aluminum salt of phosphorous acid, referred to hereinafter as PHOPAL

[0182] Melamine polyphosphate (referred to as MPP), Melapur® 200 (from BASF, D)

[0183] Component D:

[0184] Sandostab® P-EPQ, from Clariant GmbH, D

[0185] Hostanox 010, from Clariant GmbH, D

[0186] Component E:

[0187] Licowax® E, from Clariant Produkte (Deutschland) GmbH, D (ester of montan wax acid)

[0188] 2. Production, Processing, and Testing of Flame-Retardant Polymeric Molding Compositions

[0189] The flame retardant components were mixed with the phosphonite, the 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., into PPA at 300-340° C., and into PBT at 230-260° C. The glass fibers were added via a second side intake. The homogenized polymer strand was drawn off, cooled in a water bath and then pelletized. Processability was rated according to strand breakage which could happen during compounding.

[0190] After sufficient drying, the molding compositions were processed to test specimens on an injection molding machine (Arburg 320 C Allrounder) at melt temperatures of 230 to 340° C., and tested and classified for flame retardancy using the UL 94 test (Underwriter Laboratories).

[0191] The UL 94 fire classifications are as follows: [0192] 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 [0193] 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 [0194] V-2: cotton ignited by flaming drops, other criteria as for V-1

[0195] Not classifiable (ncl): does not comply with fire classification V-2.

[0196] The flowability of the molding compositions was determined by finding the melt volume flow rate (MVR) at 275° C./2.16 kg. A sharp rise in the MVR value indicates polymer degradation. MVR is also affected by fillers.

[0197] Tensile strength (N/mm.sup.2), elongation at break, and breaking strength were measured according to DIN EN ISO 527 (%), impact strength [kJ/m.sup.2] and notched impact strength [kJ/m.sup.2] in accordance with DIN EN ISO 179.

[0198] Colour of specimen was rated visually. Reference was the colour of nature polyamide which was processed with flame retardant and glass fibers as described above. Any change in colour was noted as slight, medium, heavy brownish discoloration.

[0199] The corrosion was investigated by means of the platelet method. The platelet method, developed at the OKI (Deutsches Kunststoffinstitut now Fraunhofer LBF, Darmstadt, Germany), serves for the model investigations for comparative evaluation of metallic materials and, respectively, the corrosion intensity and wear intensity of plastifying molding compositions. In this testing, two specimens are arranged in pairs in the die, so as to form a rectangular gap of 12 mm in length, 10 mm in width, and with a height of 0.1 up to a maximum of 1 mm adjustable height for the passage of the polymeric melt (FIG. 1). Through this gap, polymeric melt from a plastifying assembly is extruded (or injected), with large local shear stresses and shear rates occurring in the gap.

[0200] One parameter of wear is the weight loss of the specimens, which is determined by differential weighing of the specimens using an A&D analytical “Electronic Balance” with a deviation of 0.1 mg. The mass of the specimens was determined before and after the corrosion test, with 25 kg of polymer throughput on 1.2379 steel or 10 kg on CK 45 steel.

[0201] After a previously defined throughput (generally 25 or 10 kg), the sample platelets are demounted and are cleaned physically/chemically to remove the adhering polymer. Physical cleaning is accomplished by removing the hot polymer mass by rubbing it off with a soft material (cotton). Chemical cleaning is done by heating the specimens for 20 minutes at 60° C. in m-cresol. Polymeric composition still adhering after the boiling operation is removed by being rubbed off with a soft cotton pad.

[0202] All tests in the particular series, unless stated otherwise, were conducted under identical conditions (temperature programs, screw geometries, injection molding parameters, etc.) on account of comparability.

[0203] All quantities are reported as % by weight and are based on the polymeric molding composition including the flame retardant combination and adjuvants.

TABLE-US-00001 TABLE 1 Phosphinates and stannates in PA 66 GF (glass fiber reinforced polyamide 66). C1 C2 B1 B2 B3 B4 Polyamide 66 49.4 48.7 49.4 48.7 49.7 49.7 Glass fibers 30 30 30 30 30 30 Component A: DEPAL1 11.5 16 11.5 16 16 16 Component C: MPP 6.5 6.5 Component C: PHOPAL 2 2 3 3 Firebrake 500 1 1 Flamtard H 1 Flamtard S 3 Component B: Mg-stannate 1 Component B: Ca-stannate 1 3 1 Component E: Licowax E 0.3 0.3 0.3 0.3 0.3 0.3 Component D: P-EPQ + O10 0.3 0.3 Strand breakage rare rare no no no no UL 94 1.6 mm V-0 V-0 V-0 V-0 V-0 V-0 UL 94 0.8 mm V-1 V-1 V-0 V-0 V-0 V-0 Corrosion on 1.2379 steel [%] yes no no no no no Discoloration slight slight no no no no

[0204] Table 1 shows examples of flame retarded PA 66 molding compositions. C1 and C2 are comparative compositions which reveal the state of the art. The inventive compositions are shown as B1 to B4. Using Ca-stannate or Mg-Stannate (component B) resulted in a significant benefit in reducing corrosion. There was not any measureable corrosion. The compositions B1 to B4 showed also an improvement in flame retardancy. The highest UL 94 classification V-0 could be achieved also with thin specimen. Processing of inventive mixtures (B1 to B4) was smoother and reduction of strand breakage could give a more economical processing. Since no discoloration happened during processing of inventive mixtures (B1 to B4) application area gets broader and pigmenting or dying will be easier.

TABLE-US-00002 TABLE 2 Phosphinates and stannates in PPA GF30 (glass fiber reinforced polyphthalamide). C3 C4 B5 B6 B7 B8 B9 PPA 55 55 55 55 55 55 55 Glass fibers 30 30 30 30 30 30 30 Component A: 12 11 12 11 DEPAL1 Component A 13 13 13 and component F: DEPAL3 Component C: 1 1 PHOPAL Flamtard S 3 3 Component B: 3 3 2 Ca-stannate Component B: 2 Mg-stannate Component B: 2 Ba-stannate Corrosion on no no no no no no no 1.2379 steel [%] Strand breakage yes yes no no no no no UL 94 0.8 mm V-1 V-1 V-0 V-0 V-0 V-0 V-0 UL 94 1.6 mm V-0 V-0 V-0 V-0 V-0 V-0 V-0 Impact strength 67 60 67 68 66 not not [kJ/m.sup.2] deter- deter- mined mined Notched impact 6.8 6.3 6.9 7 6.8 not not strength [kJ/m.sup.2] deter- deter- mined mined Discoloration heavy heavy no no no no no of specimen

[0205] Table 2 shows examples of flame retarded semi aromatic polyamide molding compositions. C.sub.3 and C.sub.4 are comparative compositions which reveal the state of the art. The inventive compositions are shown as B5 to B9. All of the mentioned stannates are very good in preventing corrosion. The benefit of B5 to B9 over comparative compositions can be seen in the discoloration. While the formulation with Flametard S shows a heavy discoloration which limits application due to a lack of color choice, the inventive alkaline earth metals surprisingly did not show any discoloration of the injection molded parts. There was also an improvement in flame retardancy and the highest UL 94 class V-0 could be fulfilled in all thicknesses. Comparing C.sub.4 to B6 an improvement in impact and notched impact strength could be seen with the inventive mixture.

[0206] The molding compositions with the inventive flame retardant mixtures B5 to B9 comply with exacting fire protection requirements in accordance with UL 94, and exhibit good mechanical properties and did not show any corrosion during processing and do not show any discoloration of compounds.

TABLE-US-00003 TABLE 3 Phosphinates and stannates in PBT GF30 (glass fiber reinforced polybutylentherephthalate). C5 B10 PBT 50 50 Glass fibers 30 30 Component A and component F: 14 13 DEPAL2 Component C: MPP 7 6.5 Component B: Ca-stannate 0.5 Corrosion on CK45 steel [%] high no UL 94 0.8 mm V-0 V-0 UL 94 1.6 mm V-0 V-0 Elongation at break [%] 1.6 1.7 Tensile strength [N/mm.sup.2] 111 111

[0207] Table 3 shows examples of flame retarded polybutylenterephthalate molding compositions. C5 shows a state of the art flame retardant formulation. During processing high corrosion of processing tools could be noticed. The molding composition of the invention B10 shows no corrosion and meets exacting fire protection requirements in accordance with UL 94 VO as well as mechanical performance.