DEOXYBENZOIN CONTAINING FLAME RETARDANT POLYMER COMPOSITIONS

Abstract

The present invention relates to specific deoxybenzoin containing flame retardant polyesters and flame retardant thermoplastic polymer molding compositions comprising deoxybenzoin containing flame retardant polyesters as well as their preparation and use for producing moldings, fibers or foils.

Claims

1. A flame retardant thermoplastic polymer molding composition, comprising a) 0.1 to 99.8 wt.-% of at least one thermoplastic polymer, different from component B, as component A, b) 0.1 to 99.9 wt.-% of at least one thermoplastic polyester containing 1,2-bis[4-(2-hydroxyethoxy)phenyl]ethanone units, the thermoplastic polyester being based on at least one aromatic dicarboxylic acid, 1,2-bis[4-(2-hydroxyethoxy)phenyl]ethanone and at least one further diol, as monomers, wherein the molar ratio of 1,2-bis[4-(2-hydroxyethoxy)phenyl]ethanone to further diol is in the range of from 0.1:0.9 to 0.95:0.05 as component B, c) 0.1 to 50 wt.-% of at least one flame retardant additive, selected from phosphorus containing flame retardant additives and halogen containing flame retardant additives, as component C, d) 0 to 25 wt.-% of at least one flame retardant synergist, different from component C, selected from nitrogen compounds, metal borates, metal stannates and metal oxides, as component D, e) 0 to 60 wt.-% of glass fibers as component E, f) 0 to 30 wt.-% of at least one further additive, as component F, wherein the total amount of components A to F is 100 wt.-%.

2. The molding composition of claim 1, wherein component A is present in an amount of from 0.1 to 80 wt.-%, the total amount of components A to F being 100 wt.-%.

3. The molding composition of claim 1, wherein component B is present in an amount of from 5 to 50 wt.-%, the total amount of components A to F being 100 wt.-%.

4. The molding composition of claim 1, wherein component C is present in an amount of from 1 to 35 wt.-%, the total amount of components A to F being 100 wt.-%.

5. The molding composition of claim 1, wherein component D is present in an amount of from 0.1 to 25 wt.-%, the total amount of components A to F being 100 wt.-%.

6. The molding composition of claim 1, wherein component B is a polyester based on at least one aromatic dicarboxylic acid, 1,2-bis[4-(2-hydroxyethoxy)phenyl]ethanone and at least one aliphatic C.sub.2-12-diol, as monomers.

7. The molding composition of claim 1, wherein component C is an aluminum salt of phosphinic acid or di-C.sub.1-6-alkyl phosphinic acid, or wherein C is a brominated polystyrene, brominated polybenzyl acrylate or brominated Bisphenol-A-containing polymer.

8. The molding composition of claim 1, wherein component D is melamine polyphosphate or melamine cyanurate.

9. The molding composition of claim 1, wherein component A is at least one polyamide or polyester.

10. A process for the preparation of the molding composition of claim 1, comprising mixing the components of the molding composition.

11. A method for the production of moldings, fibers or foils, comprising processing a molding composition of claim 1 into the desired form.

12. A molding, a fiber, or a foil comprising the thermoplastic molding composition of claim 1.

13. A thermoplastic polyester based on at least one aromatic dicarboxylic acid, 1,2-bis[4-(2-hydroxyethoxy)phenyl]ethanone and at least one further diol, as monomers, wherein the molar ratio of 1,2-bis[4(2-hydroxyethoxy)phenyl]ethanone to further diol is in the range of from 0.1:0.9 to 0.95:0.05.

14. The thermoplastic polyester of claim 13, wherein the dicarboxylic acid is terephthalic acid.

15. A process for producing the thermoplastic polyester of claim 13 by polycondensation of at least one aromatic dicarboxylic acid, 1,2-bis[4-(2-hydroxyethoxy)phenyl]ethanone and at least one further diol, or chemical derivatives thereof as monomers or by transesterification of an ester containing one of the monomers with the other monomers.

16. The molding composition of claim 1, wherein the at least one further diol is a C.sub.2-12-diol.

17. The process of claim 15, wherein the at least one further diol is a C.sub.2-12-diol.

Description

EXAMPLES

[0278] Starting materials

[0279] Polyamide 6—Ultramid® B24 of BASF SE [0280] Polybutyleneterephthalate having a VZ of 120 cm3/g—Ultradur® B4500 of BASF SE [0281] Glass fiber—“PPG 3786” [0282] Glass fiber—“D1110” [0283] Red phosphorus, Italmatch Chemicals [0284] Aluminumdiethylphosphinate (DEPAL)—Exolit® OP 1240 of Clariant AG [0285] Aluminumhypophosphite CAS: 7784-22-7 [0286] Melamine polyphosphate—Melapur® M200 of BASF SE [0287] Melamine cyanurate—Melapur® MC25 of BASF SE [0288] Poly(pentabrombenzylacrylate) (PBBA) [0289] Zinkborate (ZnB) [0290] eBHDB, CAS 1190418-40-6 was prepared according to the disclosures in US2013/0102754

[0291] Compounding was performed on an DSM Xplore 15 micro-compounder. The extruder was operated with a temperature of 260° C. and a twin screw-speed of 80 min.sup.−1. The residence time for the polymers in the extruder was 3 min. For forming moldings, the polymer melt was fed to the injections molding machine Xplore micro-injection molding machine 10 cc. A mold temperature of 60° C. was employed. The injection molding was performed in three stages at 16 bar for 5 s, 16 bar for 5 s and 16 bar for 4 s. Shoulder sticks according to ISO527-2/1BA/2 were obtained in three stages at 14 bar for 5 s, 14 bar for 5 s and 14 bar for 4 s.

[0292] The flame retardancy of the molding materials was determined by method UL94-V (Underwriters Laboratories Inc. Standard of Safety, “Test for Flammability of Plastic Materials for Parts in Devices and Appliances”, pages 14 to 18, Northbrook 1998.

[0293] Thermogravimetric analysis was conducted in a nitrogen atmosphere on a TA Instruments Q50001R using a heating rate of 10° C./min. Char yields were determined by TGA from the mass of the residue remaining at the indicated temperatures.

Example 1

[0294] Polycondensation of terephthalic acid with 1,2-bis[4-(2-hydroxyethoxy)phenyl]ethanone (eBHDB) and butanediol to form poly(eBHDB-BD-terephthalate).

[0295] Transesterification of dimethylterephthalate 60.58 g (50 mol-%), 1,4-butanediol 19,68 g (35 mol-%), eBHDB 49,99 g (25 mol-%) and tetrabutylortotitanate 0.07 g was performed under nitrogen at 180 to 200° C. for 70 min. Subsequently, methanol was distilled off. The temperature of this intermediate product was increased to 240° C. in a stepwise manner and reduced pressure of 1 mbar was applied for 50 min. to obtain higher molecular weights upon polycondensation. The polymer had a molecular weight M.sub.w of 53,200 g/mol (determined by SEC).

Example 2

[0296] Polycondensation of terephthalic acid with 1.2-bis[4-(2-hydroxyethoxy)phenyl]ethanone (eBHDB) to give poly(eBHDB-terephthalate) and ethylene glycol.

[0297] The transesterification of dimethylterephthalate 30.29 g (50 mol-%), ethylene glycol 1.94 g (10 mol-%), eBHDB 49.99 g (50 mol-%) and tetrabutylorthotitanate 0.05 g was performed under nitrogen at 180 to 200° C. for min. Subsequently, methanol and ethylene glycol were distilled off. The temperature of this intermediate product was increased to 240° C. in a stepwise manner and reduced pressure of 1 mbar supplied for 50 min. in order to achieve higher molecular weights. The polymer obtained had a molecular weight M.sub.w of 14,200 g/mol, determined by SEC.

[0298] It was shown by NMR that a ratio of terephthalic acid:ethylene glycol:deoxybenzoin of 1:2:1 was achieved, corresponding to the polyester formed by terephthalic acid and eBHDB.

Example 3

[0299] The procedure of example 1 was followed using different ratios of the educts in order to obtain a series of copolymers with various ratios of butylene versus eBHDB in the polyester structure. Table A lists the ratios obtained, with the respective molecular masses, glass transition temperatures and residue after thermal decomposition.

[0300] Table A shows that higher molecular masses can be achieved through addition of butane diol (BDO) as a second diol component as compared to Example 2.

[0301] Further, FIG. 1 shows that the char yield of the polyesters formed with eBHDB and BDO is higher than the expected values. The latter can be calculated by applying the sum rule using the mass fractions of eBHDB and BDO with the char yield of PBT as the lower limit and the char yield of the polymer of example 1 as the upper limit. This is surprising, given the fact that PBT-type polyesters are generally known to have a very low char yield due to the use of BDO. The increased amount of char observed for the eBHDB and BD containing polyesters is believed to result from the improved polymerization of eBHDB in the presence of BD.

TABLE-US-00002 TABLE A Experimental composition [molar ratio vs. eBHDB [% w/w] Residual mass Residual mass Example dimethylterephthalate] (1H-NMR).sup.1 (NMR) M.sub.W (SEC).sup.2 Tg.sup.3 (TGA, N2, 650° C.) (TGA, N2, 850° C.) 3.1 0.9 BDO:0.08 eBHDB 10% 42700 50 11.48 3.2 0.8 BDO:0.18 eBHDB 20% 52300 53 16.55 3.3 0.7 BDO:0.28 eBHDB 28% 71000 56 21.26 3.4 0.6 BDO:0.37 eBHDB 35% 78900 61 26.34 1 0.5 BDO:0.5 eBHDB 42% 53200 66 30.24 3.6 0.25 BDO:0.73 eBHDB 56% 88000 74 33.43 2 0 BDO:1.0 eBHDB 68% 14200 75 35.48 30.9 .sup.1H-NMRs are measured at 400 Hz with trimethylsilane as standard. Example 1 and 2 were dissolved in deuterated chloroform, all other examples were dissolved in hexafluoro-2-propanol. .sup.2Analysis of the molecular mass was conducted by SEC. The chromatography was carried out with three columns (HFIP-LG Guard and 2x PL HFIPGel) at 40° C. with a flow of 1 ml/min of the eluent hexafluoro-2-propanol (+0.05% potassium trifluoro acetate). PMMA standards (by PSS) with a molecular weight of M = 800-1,820,000 g/mol were used for calibration. The samples were solved in the eluent (1.5 mg/ml) and filtrated via Millipore Millex FG (0.2 μm). .sup.3The glass transition temperature (Tg) was determined by differential scanning calorimetry (DSC). DSC was conducted using a TA Instruments Q2000 using sample amouns between 8 mg and 10 mg. A heating rate of 20° C./min was used to initially heat the sample to 280° C. Tg was determined upon cooling of the melt with a rate of 20° C./min.

[0302] FIG. 1 shows the residual mass (on the y axis) of the polymers listed in Table A, as determined by TGA at a temperature of 650° C. using a heating rate of 10° C./min. Squares denote the measured char yield, circles the sum rule.

Example 4

[0303] The compositions according to the following table 1 were prepared and the flame retardancy was established.

[0304] Compositions and determination according to UL94 at 1.6 mm for two samples

TABLE-US-00003 TABLE 1 Example C 4.1 4.2 4.3 Ultradur B4500 64.5 44.5 44.5 Glass fiber PPG 3786 25 25 25 poly(eBHDB-BD-terephthalate) - Ex. 1 0 20 poly(eBHDB-terephthalate) - Ex. 2 20 C1 DEPAL 8 8 8 D1 Melapur M200 2.5 2.5 2.5 Ranking V-2 V-0 V-0 burning t1 + t2 [s] 20 6 6 Floor wadding inflamed yes no no residue [%, TGA N2, 10° C./min to 600° C.] 27.7 38.2 43.2

[0305] Table 1 shows that by adding 20 wt.-% of component B the burning times are significantly reduced and a better flame retardant ranking according to UL94 could be achieved. Furthermore, the residue formed in the TGA experiment is increased by approximately 11%.

Example 5

[0306] The compositions according to table 2 were prepared and analyzed according to UL94 at 1.6 mm for two samples.

TABLE-US-00004 TABLE 2 Example C 5.1 5.2 C5.3 5.4 Ultradur B4500 58.1 36.1 55.6 35.6 Glass fiber PPG 3786 25 25 25 25 poly(eBHDB-terephthalate) - Ex. 2 0 20 0 20 C2 PBBA 16.9 16.9 16.9 16.9 D1 Melapur M200 2.5 2.5 ZnB 2 Ranking V-2 V-0 V2 V0 burning t1 + t2 [s] 25 6 18 2 Floor wadding inflamed yes no yes no

[0307] In these examples the component B of example 2 was employed. Despite the lack of butanediol units, the polymers could be mixed with PBT via extrusion, and homogeneous samples were obtained. According to the high eBHDB amount, the carbon formation was very efficient.

Example 6

[0308] The compositions according to following table 3 formed and tested according to UL94 at 1.6 mm for two samples.

TABLE-US-00005 TABLE 3 Example C 6.1 6.2 Ultradur B4500 57 37 Glass fiber PPG 3786 25 25 C1 AIHP 11.4 11.4 D1 Melapur MC25 6.6 6.6 poly(eBHDB-BD-terephthalate) - Ex. 1 20 ranking V2 V0 burning t1 + t2 [s] 11 8 Floor wadding inflamed yes no residue [%, TGA N2, 10° C./min to 600° C.] 40.3

Example 7

[0309] Tensile test according to ISO527-2/1BA/2 (5 samples)

TABLE-US-00006 TABLE 4 Example C 7.1 7.2 Ultradur B4500 75 55 Glass fiber PPG 3786 25 25 poly(eBHDB-BD-terephthalate) - Ex. 1 0 20 E-module (E-t) [Mpa] 7808 6989 maximum stress (δ_M) [Mpa] 104.7 100.3 break stress (δ_B) [Mpa] 103.2 98.3 elongation at break (ε_B) [%] 3.7 3.6

[0310] Table 4 shows that the mechanical properties are not significantly impaired by adding poly(eBHDB-BD-terephthalate).

TABLE-US-00007 TABLE 5 Example C 7.3 7.4 Ultradur B4500 75 55 Glass fiber PPG 3786 25 25 poly(eBHDB-terephthalate) - Ex. 2 0 20 E-module (E-t) [Mpa] 7845 8833 maximum stress (δ_M) [Mpa] 106.4 113 break stress (δ_B) [Mpa] 105.1 113 elongation at break (ε_B) [%] 3.3 2.1

[0311] The mechanical data show that the mixture according to the invention has a higher stiffness and a higher maximum stress when poly(eBHDB-terephthalate) is added, whereas elongation at break is reduced in comparison to poly(eBHDB-BD-terephthalate).

Example 8

[0312]

TABLE-US-00008 Example C8.1 C8.2 C8.3 poly(eBHDB-BD-terephthalate) - Ex. 3.3 64.5 0 0 poly(eBHDB-BD-terephthalate) - Ex. 1 0 69.0 0 Ultradur B4500 0 0 69.0 Glass fiber PPG 3786 25 25.0 25.0 Exolit OP 1240 8.0 6.0 6.0 Melapur 200 2.5 0 0 ranking V0 V0 V- burning t1 + t2 [s] 5 10 Floor wadding inflamed nein nein

[0313] The comparison of C7.1 to C3.1 shows that use of poly(eBHDB-BD-terephthalate)—Ex. 3.3 in stead of PBT results in superior flame resistance.

Example 9

[0314]

TABLE-US-00009 Example C9.1 C9.2 C9.3 C9.4 Ultramid B24 65.8 51.8 70.0 60.0 poly(eBHDB-BD-terephthalate) - Ex. 3.6 0 20.0 0 0 poly(eBHDB-BD-terephthalate) - Ex. 2 0 0 0 10.0 Glass fiber DS 1110 21.6 15.6 25.0 25.0 Aluminumhypophosphite 12.6 12.6 0 0 Exolit OP1240 0 0 0 0 Melapur 200 0 0 0 0 Red phosphorus 0 0 5.0 5.0 ranking V- V0 V- V-1 burning t1 + t2 [s] 8 23 Floor wadding inflamed no no

[0315] Example 9 shows that melt blending of PA6 with eBHDB based co-polyester can significantly improve flame retardancy. C9.2 shows a V0 rating and was easy to process. C9.4 shows how the FR effect of red phosphorus, usually used in PA66 not PA6, is improved by melt blending PA6 with the product of Example 2.