IMPACT-RESISTANT THERMOPLASTIC POLYURETHANES, PRODUCTION AND USE THEREOF

Abstract

The present invention relates to polyester-based hard thermoplastic polyurethane systems which are impact-resistant at low temperatures, and to the production and use thereof.

Claims

1-10. (canceled)

11. A thermoplastically processable polyurethane elastomer (TPU) having a hardness of 56 to 85 Shore D (according to ISO 7619-1: 2012-02) obtained from the reaction of the components a) one or more substantially linear polyester polyols having a number-average functionality of 1.8 to 2.2 and a number-average molecular weight of 500 to 4000 g/mol based on dicarboxylic acids selected from the group consisting of adipic acid, succinic acid, terephthalic acid and derivatives thereof, and based on dialcohols selected from the group consisting of ethanediol, 1,4-butanediol, 1,3-propanediol, 1,6-hexanediol and neopentyl glycol, and optionally 0% to 60% by weight of polycarbonate diol based on 1,6-hexanediol, b) one or more substantially linear polyether polyols having a number-average functionality of 1.9 to 2.1 and a number-average molecular weight of 4000 to 20 000 g/mol based on propylene oxide or propylene oxide/ethylene oxide mixtures, c) one or more linear organic diisocyanates, d) one or more dials having a number-average molecular weight of 60 to 250 g/mol, in the presence of e) optionally catalysts, f) optionally auxiliary and/or additive substances, g) optionally monofunctional chain terminators, wherein the molar ratio of NCO groups to OH groups is from 0.9:1 to 1.1:1 and the weight ratio of the polyether polyols (b) to the polyester polyols (a) is from 5:95 to 30:70.

12. The thermoplastically processable polyurethane elastomer as claimed in claim 11, wherein the component (a) is a linear polyester polyol having a number-average molecular weight of 900 to 2500 g/mol and/or a polycarbonate diol having a number-average molecular weight of 1000 to 4000 g/mol.

15. The thermoplastically processable polyurethane elastomer as claimed in claim 11, wherein component (b) is a linear polyether polyol having a number-average molecular weight of 4000 to 12 000 g/mol, preferably of 4000 to 8500 g/mol.

14. The thermoplastically processable polyurethane elastomer as claimed in claim 11, wherein component (c) consists of one or more diisocyanates selected from the group consisting of 4,4-diphenylmethane diisocyanate, 4,4-dicyclohexylmethane diisocyanate and 1,6-hexamethylene diisocyanate.

15. The thermoplastically processable polyurethane elastomer as claimed in claim 11, wherein component (d) consists of one or more diols selected from the group consisting of 1,4-butanediol, 1,3-propanediol, 1,2-ethylene glycol, 1,6-hexanediol and hydroquinone monomethyl ether.

16. The thermoplastically processable polyurethane elastomer as claimed in claim 11, wherein component (a) is selected from one or more compounds from the group consisting of 1,4-butanediol polyadipates, 1,6-hexanediol polyadipates, ethanediol 1,4-butanediol polyadipates, 1,6-hexanediol neopentyl glycol polyadipates, 1,6-hexanediol 1,4-butanediol polyadipates, component (b) is selected from polypropylene oxides or polyethylene/polypropylene oxides having molecular weights of 4000 to 12 000 g/mol, component (c) is selected from 4,4-diphenylmethane diisocyanate and/or hexamethylene diisocyanate and component (d) is selected from 1,4-butanediol, ethanediol and/or 1,6-hexanediol.

17. A process for continuous production of a thermoplastically processable polyurethane as claimed in claim 11, wherein components (a), (b), (c) and (d) and optionally (e) to (g) are metered into a reaction extruder and while passing through the extruder react to afford the polyurethane.

18. A method comprising utilizing the TPU as claimed in claim 11 for producing a molded article that are subjected to low temperatures (<0 C.).

19. The method of the TPU as claimed in claim 18, wherein the molded article is a ski shoes.

20. A method comprising utilizing a polyether polyols (b) having a number-average functionality of 1.9 to 2.1 and a number-average molecular weight of 4000 to 20 000 g/mol based on propylene oxide or propylene oxide/ethylene oxide mixtures as a low-temperature impact modifier in the production of thermoplastically processable polyurethanes.

Description

EXAMPLES

Raw Materials Employed

[0035] Tyzor AA105: titanium catalyst from Dorf Ketal

[0036] Polyether LP112: polypropylene glycol having a molecular weight of 1000 g/mol, commercially available product from Covestro AG

[0037] Irganox 1010: antioxidant from BASF SE

[0038] Licowax E: demolding agent from Clariant

[0039] Baysilone M1000: silicone oil from Momentive

[0040] Stabaxol I: hydrolysis stabilizer from Rheinchemie

FM Formulation Example 1:

[0041]

TABLE-US-00001 Polybutanediol 1,4-adipate (molecular weight 36.30% by weight about 2250 g/mol): 1,4-Butanediol; 14.62% by weight 1,6-Hexanediol: 0.91% by weight 4,4-Diphenylmethanediisocyanate (4,4-MDI): 46.57% by weight 0.1% solution of Tyzor AA 105 in polyether 0.15% by weight LP112: Irganox 1010: 0.24% by weight Licowax E: 0.30% by weight Stearyl alcohol 0.24% by weight Baysilon M1000: 0.02% by weight Triphenylphosphine: 0.47% by weight Stabaxol I: 0.18% by weight

Example 1 (Production of TPU 1)

[0042] 36.30% by weight of polybutanediol 1,4-adipate (molecular weight about 2250 g/mol) were initially charged in a reaction vessel. 0.24% by weight of Irganox 1010, 0.3% by weight of Licowax E, 0.24% by weight of stearyl alcohol, 0.02% by weight of Baysilon M1000 0.47% by weight of triphenylphosphine and 0.18% by weight of Stabaxol I were dissolved therein. After heating to 180 C., 46.6% by weight of 4,4-diphenylmethane diisocyanate (MDI) were added with stirring and the reaction was carried out using 10 ppm of Tyzor AA105 (based on the polyol amount).

[0043] Once the reaction was complete 14.6% by weight of 1,4-butanediol and 0.9% by weight of 1,6-hexanediol were added with stirring and the NCO/OH ratio of all components was 1.0. The polymer melt was subjected to intensive mixing up to the maximum stirrable viscosity and then poured onto a tray. The polymer melt was subsequently heat-treated at 120 C. for 30 minutes.

Production of TPU 2 to 11

[0044] Production was carried out analogously to example 1, but instead of polybutanediol 1,4-adipate the mixtures of polybutanediol 1,4-adipate and the corresponding amount in weight percent of polyether polyol reported in table 1 were employed.

Measurements

[0045] Hardness was measured according to ISO7619-1: 2012-02 and tensile measurements were carried out according to ISO 53504: 2009-10.

Charpy Impact Strength Testin

[0046] Charpy impact strength tests were carried out on injection molded test specimens according to DIN EN ISO179/1eA: 2010 at 20 C. The test specimen has dimensions of: 802 mm length, 10.00.2 mm breadth and 4.00.2 mm thickness. The test specimen is notched. The notch base radius r.sub.N is 0.250.05 mm (see FIG. 1)

[0047] The measured properties of the examples are described in table I which follows:

TABLE-US-00002 TABLE 1 Composition and properties of the TPU of examples 1 to 11 10% 100% Charpy Average value Amount of modulus modulus and type of break Example polyether polyal Hardness [MPa] [MPa] [KJ/m.sup.2] 1.sup. 0% by weight 64 Shore D 16.60 27.70 4.99 s.sup.+) 2*.sup.) 10% by weight 64 Shore D 18.90 28.80 8.29 s.sup.+) Acclaim 4200.sup.1) 3*.sup.) 15% by weight 64 Shore D 20.10 28.90 10.76 s.sup.+) Acclaim 4200.sup.1) 4*.sup.) 20% by weight 64 Shore D 20.90 28.60 13.26 s.sup.+) Acclaim 4200.sup.1) 5*.sup.) 10% by weight 64 Shore D 19.0 29.40 5.98 s.sup.+) Acclaim 8200.sup.2) 6*.sup.) 10% by weight 64 ShoreD 19.2 31.9 8.19 s.sup.+) Acclaim 12200.sup.3) 7*.sup.) 10% by weight 64 Shore D 19 31.6 7.06 s.sup.+) Acclaim 18200.sup.4) 8.sup. 10% by weight 64 ShoreD 16.5 29.6 4.4 s.sup.+) Acclaim 2200.sup.5) 9.sup. 20% by weight 64 ShoreD 19.0 29.4 5.89 s.sup.+) Acclaim 2200.sup.5) 10.sup. 10% by weight 64 ShoreD 16.7 29.5 6.49 s.sup.+) Terathane 2000.sup.6) 11.sup. 10% by weight 64 ShoreD 15.7 28 7.16 s.sup.+) Terathane 2900.sup.7) *.sup.)Inventive example .sup.1)Acclaim 4200 is a linear polypropylene ether polyol (commercially available product from Covestro Deutschland AG, molecular weight about 4000) .sup.2)Acclaim 8200 is a linear polypropylene ether polyol (commercially available product from Covestro Deutschland AG, molecular weight about 8000) .sup.3)Acclaim 12200 is a linear polypropylene ether polyol (commercially available product from Covestro Deutschland AG, molecular weight about 12 000) .sup.4)Acclaim 18200 is a linear polypropylene ether polyol (commercially available product from Covestro Deutschland AG, molecular weight about 18 000) .sup.5)Acclaim 2200 is a linear polypropylene ether polyol (commercially available product from Covestro Deutschland AG, molecular weight about 2000) .sup.6)Terathane 2000 is a linear polytetramethylene ether glycol (commercially available product from Invista, molecular weight about 2000) .sup.7)Terathane 2900 is a linear polytetramethylene ether glycol (commercially available product from Invista, molecular weight about 2900) .sup.+)type of break: s = brittle and z = tough

[0048] It is apparent that in the inventive examples containing polypropylene ether polyols having molecular weights of 4000 to 20 000 g/mol the Charpy values are considerably higher than in example 1 which contains no polyether polyol and in examples 8 to 11 which do not contain the polyether polyols according to the present invention. Accordingly the impact strength of the inventive TPU (examples 2 to 7) is better than that of the TPU from comparative examples 1 and 8 to 11.