Flame retardant-stabilizer combination for thermoplastic polymers

Abstract

The invention relates to a novel flame retardant-stabilizer combination for thermoplastic polymers, comprising, as component A, from 25 to 99.9% by weight of a phosphinic acid salt of the formula (I) wherein R.sup.1, R.sup.2 are the same or different and are each C.sub.1-C.sub.8-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.sub.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; as component B, from 0 to 75% by weight of a synergist or of a phosphorus/nitrogen flame retardant and, as component C, from 0.1 to 30% by weight of telomeric phosphinic acid salts as component D, from 0 to 20% by weight of organo phosphonic acid salt, as component E, from 0 to 5% by weight of phosphonic acid salt, the sum of the components always being 100% by weight, and wherein the angle of repose of said flame retardant-stabilizer combination is between 5° and 45°. ##STR00001##

Claims

1. A flame retardant-stabilizer combination for thermoplastic polymers, comprising, as component A, from 25 to 99.7% by weight of a phosphinic acid salt of the formula (I) ##STR00007## wherein R.sup.1, R.sup.2 are the same or different and are each methyl, ethyl, n-propyl or isopropyl, 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; as component B, from 0.1 to 75% by weight of a synergist or of a phosphorus/nitrogen flame retardant selected from the group consisting of: a) condensation products of melamine, b) reaction products of melamine with polyphosphoric acid, reaction products of condensation products of melamine with polyphosphoric acid and mixtures thereof, as component C, from 0.1 to 10% by weight of telomeric phosphinic acid salts of formula (XIII)
H—(C.sub.wH.sub.2w).sub.kP(O)(OMe)(C.sub.xH.sub.2x).sub.l—H  (XIII) where, in formula (XIII), independently from each other, k is from 1 to 3, l is from 1 to 3, w is from 2 or 3, x is from 2 or 3, Me is minimum one of the cations of the group Mg, Ca, Al, Sb, Sn, Ge, Ti, Fe, Zr, Zn, Ce, Bi, Sr, Mn, Li, Na and/or K, as component D, from 0.1 to 5% by weight of organo phosphonic acid salt, and as component E, from 0 to 1% by weight of phosphonic acid salt, the sum of the components always being 100% by weight, and wherein the angle of repose of said flame retardant-stabilizer combination is between 5° and 45°, and wherein the tap density of said flame retardant-stabilizer combination is between 200 g/L and 1100 g/L.

2. The flame retardant-stabilizer combination as claimed in claim 1, wherein the angle of repose of said flame retardant-stabilizer combination is between 20° and 40°.

3. The flame retardant-stabilizer combination as claimed in claim 1, wherein M is a calcium, aluminum, zinc, titanium or iron ion.

4. The flame retardant-stabilizer combination as claimed in claim 1, wherein component B is melamine polyphosphate.

5. The flame retardant-stabilizer combination as claimed in claim 1, wherein Me is a cation of the group Al, Ti, Fe and/or Zn.

6. The flame retardant-stabilizer combination as claimed in claim 1, wherein component D is alkyl phosphonate according to formula (II) ##STR00008## wherein R.sup.3 is an ethyl, propyl and/or butyl group, M is Mg, Ca, Al, Zn or Fe and m is from 1 to 4.

7. The flame retardant-stabilizer combination as claimed in claim 1, wherein component E is a phosphite according to formula (IX); ##STR00009## wherein R.sup.3 is H, M is Mg, Ca, Al, Zn or Fe and m is from 1 to 4.

8. The flame retardant-stabilizer combination as claimed in claim 1, wherein the residual moisture content of said flame retardant-stabilizer combination is between 0.01 wt.-% and 10 wt.-%.

9. The flame retardant-stabilizer combination as claimed in claim 1, wherein the residual moisture content of said flame retardant-stabilizer combination is between 0.1 wt.-% and 1 wt.-%.

10. The flame retardant-stabilizer combination as claimed in claim 1, wherein the bulk density of said flame retardant-stabilizer combination is between 100 g/L and 1000 g/L.

Description

EXAMPLES

(1) 1. Component s Used

(2) Standard Commercial Polymers (Granules):

(3) PA 6,6 GF: Durethan® AKV 30 (Bayer AG, D), contains 30% glass fibers.

(4) PBT GF: Celanex® 2300 GV1/30 (Ticona, D), contains 30% glass fibers.

(5) PA 6: Ultramid® B 27 E

(6) PA 6,6: Ultramid® A 27 E (BASF)

(7) Glass fiber: PPG Glass fiber HP 3610 EC 10 4.5 mm

(8) Flame Retardant Components (Pulverulent):

(9) Component A: Aluminum salts of diethylphosphinic acid, referred to hereinbelow as DEPAL. Component B: Melapur® 200 (melamine polyphosphate, MPP), from BASF Component B: Aluminiumphosphite (AP) according to DE-A-102014001222 Component C1: Butylethyl phosphinic acid, aluminium salt Component C2: Dibutyl phosphinic acid, aluminium salt Component C3: Ethyl-phenylethyl phosphinic acid, aluminium salt Component D1: Ethyl phosphonic acid, aluminium salt Component D2: Butyl phosphonic acid, aluminium salt Component E1: Phosphonic acid, aluminium salt
2. Production, Processing and Testing of Flame-Retardant Plastics Molding Compositions

(10) The flame-retardant component s were mixed with the polymer granules, lubricants and stabilizers in the ratio specified in the tables and incorporated in a Leistritz LSM 30/34 double-screw extruder at temperatures of from 260 to 310° C. (GFR PA-6,6) or from 240 to 280° C. (GFR PBT). The homogenized polymer strand was drawn off, cooled in a water bath and then granulated.

(11) After sufficient drying, the molding compositions were processed to give test specimens on a Arburg 320 C Allrounder injection molding machine at temperatures of from 270 to 320° C. (GFR PA-6,6) or from 260 to 280° C. (GFR PBT) and, with the aid of the UL 94 test (Underwriter Laboratories), were tested for flame resistance and classified.

(12) The flowability of the molding composition was determined by determining the melt volume index (MVR) at 275° C./2.16 kg. A sharp rise in the MVR value indicated polymer degradation.

(13) The processing properties in polyester were assessed with reference to the specific viscosity (SV). After sufficient drying, the plastics molding composition granules were used to prepare a 1.0% solution in dichloroacetic acid and the SV value was determined. The higher the SV value is, the lower was the polymer degradation during the incorporation of the flame retardant.

(14) Unless stated otherwise, all experiments of a particular series were carried out under identical conditions (temperature program, screw geometries, injection molding parameters, etc.) for the purpose of comparability.

(15) Thus, for the inventive flame retardant-stabilizer combinations of components A, B, C, D and E an improvement in the angle of repose can be detected.

(16) One can obtain an improvement in the angle of repose if only components A and C are used in the inventive flame retardant-stabilizer combination.

(17) Unless stated otherwise, the amounts quoted are always in percent by weight.

(18) In the present invention, angle of repose were used to evaluate the flowability of said dialkylphosphinate. For example, to measure the angle of repose, the powder sample was poured through a funnel and dropped down to a round plate with a radius of r. The powder was continuously poured into the funnel and accumulated into a cone-shaped pile growing up until the height of the pile did not increase. The height of the pile, h, was measured and the angle of repose, a, was calculated according to formula (1)
tgα=h/r  (1)

(19) The smaller α is, the better the flowability of the powder is. Generally, when α is smaller than 30°, the powder can flow freely; when α is between 30° and 40°, the powder can meet the processing requirements; when α is greater than 40°, the powder cannot meet the processing requirements.

Example 1 (Comparison)

(20) A sample produced according to CN-A-104059101 was tested for its angle of repose. The result is listed in table 1.

Example 2

(21) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and component C1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 3

(22) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and component C1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 4

(23) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and component D1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 5

(24) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and component D1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 6

(25) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and component E1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 7

(26) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and component E1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 8

(27) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and components C1 and D1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 9

(28) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and components C2 and D2 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 10

(29) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and components C1 and E1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 11

(30) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and components C2 and E1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 12

(31) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and components C1, D1 and E1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 13

(32) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate and components C3, D2 and E1 in types and amounts according to table 1. It was tested for its angle of repose, the result is listed in table 1 and is better than comparative example 1.

Example 14

(33) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate, component B and component C1 in types and amounts according to table 1. It was tested for its angle of repose, the very good result is listed in table 1.

Example 14a (Comparison)

(34) A flame retardant-stabilizer combination was mixed from 66.5 wt.-% aluminiumdiethylphosphinate and 33.8 wt.-% component B. It was tested for its angle of repose of 35 degrees, which was worse than pure aluminiumdiethylphosphinate.

Example 15

(35) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate, component B and component C1 in types and amounts according to table 1. It was tested for its angle of repose, the very good result is listed in table 1.

Example 16

(36) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate, component B, component C1, component D1 and component E1 in types and amounts according to table 1. It was tested for its angle of repose, the very good result is listed in table 1.

Example 17

(37) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate, component B, component C1, component D2 and component E1 in types and amounts according to table 1. It was tested for its angle of repose, the very good result is listed in table 1.

Example 18

(38) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate, component B, component C1 and component D1 in types and amounts according to table 1. It was tested for its angle of repose, the very good result is listed in table 1.

Example 18a (Comparison)

(39) A flame retardant-stabilizer combination was mixed from 82.1 wt.-% aluminiumdiethylphosphinate and 17.9 wt.-% component B. It was tested for its angle of repose of 30 degrees, which was worse than pure aluminiumdiethylphosphinate.

Example 19

(40) A flame retardant-stabilizer combination according to the invention was mixed from aluminiumdiethylphosphinate, component B, component C1 and component D2 in types and amounts according to table 1. It was tested for its angle of repose, the very good result is listed in table 1.

(41) TABLE-US-00001 TABLE 1 Compositions of flame retardant-stabilizer combinations and angles of repose Alu- Angle minium- phos- component of pinate B C D E repose Example [wt.-%] [wt.-%] [wt.-%] [wt.-%] [wt.-%] [°]  1 (Com) 100 — — — — — — — — 25  2 99.9 — — C1 0.1 — — — — 23  3 80 — — C1 20 — — — — 24.9  4 99.99 — — — — D1 0.01 — — 22.9  5 95 — — — — D1 5 — — 24  6 99.99 — — — — — — E1 0.01 23.2  7 95 — — — — — — E1 5 24.5  8 99.69 — — C1 0.3 D1 0.01 — — 24.1  9 93 — — C2 5 D2 2 — — 24.7 10 99.69 — — C1 0.3 — — E1 0.01 24.2 11 94.7 — — C2 5 — — E1 0.3 24.5 12 99.68 — — C1 0.3 D1 0.01 E1 0.01 24.3 13 97.75 — — C3 2 D2 0.05 E1 0.2 24.5 14 66.2 MPP 32.6 C1 1.2 — — — — 27 15 63.7 MPP 31.4 C1 5 — — — — 30 16 66.2 MPP 32.6 C1 1.2 D1 0.03 E1 0.01 26 17 62.5 MPP 30.9 C1 5 D2 1.5 E1 0.2 27 18 81.5 AP 17.9 C1 0.6 D1 0.05 — — 26 19 80.0 AP 17.6 C1 1.4 D2 1 — — 26

Example 20

(42) An inventive flame-retardant molding composition comprising the combination of aluminiumdiethylphosphinate, component B, component C1 and zinc borate in glass fiber-reinforced PA-6 was produced in the composition according to table using a melt temperature on injection molding of 290° C.

Example 21

(43) An inventive flame-retardant molding composition comprising the combination of aluminiumdiethylphosphinate, component C3, component D2, component E1 and zinc borate in glass fiber-reinforced PA-6,6 was produced in the composition according to table using a melt temperature on injection molding of 300° C.

Example 22

(44) An inventive flame-retardant molding composition comprising the combination of aluminiumdiethylphosphinate, component B, component C1, component D1, component E1 in glass fiber-reinforced PA-6,6 was produced in the composition according to table using a melt temperature on injection molding of 300° C.

Example 23

(45) An inventive flame-retardant molding composition comprising the combination of aluminiumdiethylphosphinate, component B, component C1, component D1, component E1 in glass fiber-reinforced PA-6,6 was produced in the composition according to table using a melt temperature on injection molding of 300° C.

Example 24

(46) An inventive flame-retardant molding composition comprising the combination of aluminiumdiethylphosphinate, component B, component C1, component D1, component E1 in glass fiber-reinforced PA-6,6 was produced in the composition according to table using a melt temperature on injection molding of 300° C.

Example 25

(47) An inventive flame-retardant molding composition comprising the combination of aluminiumdiethylphosphinate, component B and component C in glass fiber-reinforced PBT was produced in the composition according to table using a melt temperature on injection molding of 275° C.

(48) TABLE-US-00002 TABLE 2 Compositions of flame-retardant molding compositions and test results Glas fiber Zinc Flame retard.-stab. UL 94 class Polymer (calc.) borate comb (0.8 mm) Example Type [wt.-%] [wt.-%] [wt.-%] acc. to exp. [wt.-%] [-] 20 PA 6 52 30 0.72 14 18 V-0 21 PA 6, 6 80 0 0.8 13 20 V-0 22 PA 6, 6 72 10 — 16 18 V-0 23 PA 6, 6 GF 82 (24.6) — 18 18 V-0 24 PA 6, 6 42 40 — 16 18 V-0 25 PBT GF 82 (24.6) — 16 18 V-0

(49) In general the angle of repose of aluminiumdiethylphosphinate plus components C and/or D and/or E are better than of pure aluminiumdiethylphosphinate (comparison example).

(50) The angle of repose of aluminiumdiethylphosphinate plus components B and C and/or D and/or E are better than of aluminiumdiethylphosphinate plus components B (comparison example 14a, 18a).