ALIPHATIC THERMOPLASTIC POLYURETHANES, PRODUCTION AND USE THEREOF

Abstract

The present invention relates to aliphatic, lightfast thermoplastic polyurethanes having improved blooming behaviour, good heat resistance and fast industrial processability, and the preparation and use thereof.

Claims

1.-14. (canceled)

15. An aliphatic, light-stable thermoplastic polyurethanes obtained from A) an isocyanate component consisting of a1) from 100 to 70 mol % of 1,10-diisocyanatodecane and/or 1,12-diisocyanatododecane, a2) 0-30 mol % of one or more aliphatic, cycloaliphatic and/or aromatic diisocyanates with the exception of 1,10-diisocyanatodecane and 1,12-diisocyanatododecane, B) at least one polyol component selected from the group consisting of polyester polyols, polyether polyols, polyether ester polyols, polycarbonate polyols and polyether carbonate polyols, in each case having number average molecular weights of from 500 to 8000 g/mol, C) at least one chain extender component, selected from the group consisting of ethanediol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1,2-dodecanediol, 1,4-cyclohexanediol, bis(hydroxymethyl)cyclohexane, 1,4-di(hydroxyethyl)hydroquinone, neopentyl glycol, 1,4-butenediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, dibutylene glycol, bis(ethylene glycol) terephthalate, bis(1,3-propanediol) terephthalate, bis(1,4-butanediol) terephthalate, ethoxylated bisphenols, ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, N-methylpropylenediamine, N,N-dimethylethylenediamine, isophoronediamine, 2,4-toluylenediamine, 2,6-toluylenediamine, 3,5-diethyl-2,4-toluylenediamine, 3,5-diethyl-2,6-toluylenediamine, and 2-hydroxyethylamine, D) optionally monofunctional chain terminators in the presence of E) optionally catalysts, F) from 0.05 to 5% by weight, based on the thermoplastic polyurethane, of oxidation and/or light stabilizers, G) optionally further additives and/or auxiliaries, where the ratio of the isocyanate groups from A) to the groups which are reactive toward isocyanate groups from B), C) and D) is from 0.9:1 to 1.1:1.

16. The aliphatic, lightfast thermoplastic polyurethanes according to claim 15, wherein the isocyanate component A) consists of a1) from 100 to 70 mol % of 1,10-diisocyanatodecane and/or 1,12-diisocyanatododecane, a2) from 0 to 30 mol % of one or more aliphatic and/or cycloaliphatic diisocyanates, with the exception of 1,10-diisocyanatodecane and 1,12-diisocyanatododecane.

17. The aliphatic, lightfast thermoplastic polyurethanes according to claim 15, wherein the isocyanate component A) consists of a1) from 100 to 70 mol % of 1,10-diisocyanatodecane and/or 1,12-diisocyanatododecane, a2) from 0 to 30 mol % of one or more aliphatic diisocyanates, with the exception of 1,10-diisocyanatodecane and 1,12-diisocyanatododecane.

18. The aliphatic, lightfast thermoplastic polyurethanes according to claim 15, wherein the isocyanate component A) consists of a1) from 100 to 70 mol % of 1,10-diisocyanatodecane and/or 1,12-diisocyanatododecane, a2) 0-30 mol % of 1,6-diisocyanatohexane.

19. The aliphatic, lightfast thermoplastic polyurethanes according to claim 15, wherein the polyols of component B) each have number average molecular weights of from 750 to 6000 g/mol.

20. The aliphatic, lightfast thermoplastic polyurethanes according to claim 15, wherein the polyols of component B) each have number average molecular weights of from 900 to 4200 g/mol.

21. The aliphatic, lightfast thermoplastic polyurethanes according to claim 15, wherein component C) is one or more chain extenders selected from the group consisting of ethanediol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1,2-dodecanediol, 1,4-cyclohexanediol, bis(hydroxymethyl)cyclohexane, 1,4-di(hydroxyethyl)hydroquinone, neopentyl glycol, diethylene glycol, dipropylene glycol, dibutylene glycol, bis(ethylene glycol) terephthalate, ethylenediamine, isophoronediamine, 2,4-toluylenediamine and 2-hydroxyethylamine.

22. The aliphatic, lightfast thermoplastic polyurethanes according to claim 15, wherein component C) is one or more chain extenders selected from the group consisting of ethanediol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol and 1,4-di(hydroxyethyl)hydroquinone.

23. A process for the continuous preparation of the aliphatic, lightfast thermoplastic polyurethanes according to claim 15, comprising i) mixing the polyol component B) and the chain extender component C) forming a mixture, ii) reacting the mixture from step i) with the isocyanate component A), iii) the reaction is completed in a discharge vessel, and the product is optionally pelletized, with the addition of the component F) being able to be carried out at any point in steps i) and ii).

24. The process for the continuous preparation of the aliphatic, lightfast thermoplastic polyurethanes according to claim 15, wherein i) the isocyanate component A) and the polyol component B) are continuously mixed and reacted, ii) the resulting reaction product from step i) is reacted with the chain extender component C), iii) the reaction is completed in a discharge vessel, and the product is optionally pelletized, with the addition of the component F) being able to be carried out at any point in steps i) and ii).

25. Use of the aliphatic, lightfast thermoplastic polyurethanes according to claim 15 for producing extrudates and injection-moulded parts.

26. A method comprising utilizing the aliphatic, lightfast thermoplastic polyurethanes according to claim 15 as sinterable powder for producing sheet-like structures and hollow bodies.

27. Mouldings, films or sheets obtained from the thermoplastic polyurethanes according to claim 15.

28. A sinterable powder obtained from the thermoplastic polyurethanes according to claim 15.

Description

EXAMPLES

[0060] Abbreviations used in the following:

[0061] PE225B: Polybutylene adipate having an OH number of 50 mg KOH/g

[0062] Acclaim 2220N: Polyether (C3/C2 mixed ether) having an OH number of 50 mg KOH/g

[0063] Desmophen C2201: Polycarbonate diol having an OH number of 56 mg KOH/g

[0064] HDI: 1,6-diisocyanatohexane

[0065] HDO: 1,6-hexanediol

[0066] DDI: 1,10-diisocyanatodecane

[0067] T2000: Polytetrahydrofuran having an OH number of 56 mg KOH/g

[0068] Irganox 245: Antioxidant from BASF SE

[0069] Tinuvin 234: Light stabilizer based on a benzotriazole from BASF SE

[0070] Stabaxol P200: Hydrolysis inhibitor from Rhein Chemie GmbH

[0071] DBTL: Dibutyltin dilaurate

[0072] General Description of the Preparation of the TPUs:

[0073] A mixture of the respective polyol or polyol mixture (in the case of PE225B, 1% by weight of Stabaxol P200 was added 3 hours before commencement of the experiment), HDO, Irganox 245 (0.5% by weight) based on TPU), Tinuvin 234 (0.2% by weight based on TPU) and 80 ppm of DBTL (based on the amount of polyol) was heated to 120 C. while stirring. The respective diisocyanate was then added. The mixture was subsequently stirred until the maximum possible viscosity increase had occurred and the TPUs were then cast to give a cast TPU plate. The plates were then thermally after-treated at 80 C. for 30 minutes. They were then cooled to room temperature. The molar compositions of the TPUs prepared are shown in Table 1.

TABLE-US-00001 TABLE 1 Molar composition of the TPUs prepared Acclaim Desmophen Exam- PE225B 2220N C2201 T2000 HDO DDI HDI ple [mol] [mol] [mol] [mol] [mol] [mol] [mol] 1 0.7 0.3 2.04 3.04 2* 0.7 0.3 2.04 3.04 3 0.5 0.5 4.95 6.95 4* 0.5 0.5 4.95 6.95 *not according to the invention

[0074] The cast TPU plates obtained were cut and pelletized. The pellets were processed using an Arburg Allrounder 470S injection-moulding machine in a temperature range from 180 to 230 C. and in a pressure range from 650 to 750 bar at an injection rate of from 10 to 35 cm.sup.3/s to give bars (mould temperature: 40 C.; bar size: 80104 mm) or plates (mould temperature: 40 C.; size: 125502 mm).

[0075] The melt flow index (MVR) and the mechanical properties (100% modulus, 300% modulus, ultimate tensile strength, elongation at break and Shore A hardness), the solidification rate, the abrasion and the blooming behaviour were determined on the TPU products produced.

[0076] Test Conditions:

[0077] 1) Melt Flow Index (MVR):

[0078] The MVR measurements were carried out at 170 C. (Examples 1+2) and 200 C. (Examples 3+4) under a load of 10 kg (98N) with a preheating time of 5 min. in accordance with ISO 1133 using an MVR instrument from Gttfert, model MP-D.

[0079] 2) Tensile Test:

[0080] The tensile test was carried out on Si bars (corresponds to test specimens type 5 in accordance with EN ISO 527, stamped out from injection-moulded plates) in accordance with DIN 53455 at a strain rate of 200 mm/min.

[0081] 3) Hardness:

[0082] The measurement of the hardness was carried out in accordance with DIN 53505.

[0083] 4) Solidification Rate:

[0084] To determine the solidification rate, the development of hardness of round mouldings (diameter 30 mm, height 6 mm) was measured after processing by injection moulding (setting of the injection-moulding machine: 25 s cooling time and 25 s pressure dwell time). Here, the hardness of the test specimens in accordance with DIN 53505 was measured immediately after removal from the mould (0 s), after 60 s and after 300 s.

[0085] 5) Abrasion:

[0086] The measurement of abrasion was carried out in accordance with DIN ISO 4649

[0087] 6) Blooming Behaviour:

[0088] The blooming behaviour was determined on injection-moulded plates. For this purpose, the plates were stored under various conditions (at 25 C. ambient air, at 45 C. under water and at 60 C./90% atmospheric humidity in an air conditioned cabinet). After a storage time of 4 weeks, the test plates were assessed visually.

[0089] The measured values for the melt flow index (MVR) and those of the tensile test (mechanics) are shown in Table 2 below.

TABLE-US-00002 TABLE 2 Ultimate 100% 300% tensile MVR modulus modulus strength Elongation at Shore A TPU from [ml/10 min.] [MPa] [MPa] [MPa] break [%] hardness Example 1 41.4 6.4 10.1 22.5 814 88 Example 2* 90.1 5.7 9.0 21.5 863 85 Example 3 29.5 8.1 24.3 196 93 Example 4 6.4 7.9 25.6 128 93 *not according to the invention

[0090] The measured values for the solidification rate and the abrasion are shown in Table 3 below.

TABLE-US-00003 TABLE 3 Shore A Shore A Shore A hardness after hardness hardness after Abrasion TPU from 0 s after 60 s 300 s [mm.sup.3] Example 1 50 78 82 47 Example 2* 31 73 79 70 Example 3 91 93 93 18 Example 4* 81 90 93 36 *not according to the invention

[0091] The blooming behaviour was determined on Examples 1 and 2. The visual assessments are shown in Table 4 below.

TABLE-US-00004 TABLE 4 60 C./90% TPU from 25 C. air 45 C. under water atmospheric humidity Example 1 No coating Slight bloom Slight bloom Example 2* No coating Much white coating Much white coating *not according to the invention

[0092] The mechanical data of the TPUs from Examples 1 to 4 (Table 2) are at a comparable level. The MVR values are different, which is attributed to the different polymer compositions but is not relevant to the performance of a TPU.

[0093] The solidification rate and the abrasion values (Table 3) display significant advantages of the TPUs according to the invention compared to the TPUs which are not according to the invention. Thus, the abrasion values in mm.sup.3 of the TPUs of the invention are significantly lower than the abrasion values of the TPUs which are not according to the invention. The solidification rate of the TPUs according to the invention after processing by injection moulding is faster than that of the TPUs which are not according to the invention, which can clearly be seen from, in particular, the higher Shore A hardnesses after 0 and 60 seconds (faster increase in hardness).

[0094] In the tests for determining the blooming behaviour, the TPUs according to the invention display significant advantages on storage under water at 45 C. and on storage in an air conditioned cabinet at 60 C. and 90% atmospheric humidity. At 25 C. in ambient air, no formation of a coating is observed for the test plates tested.