HARD-PHASE-MODIFIED THERMOPLASTIC POLYURETHANE

Abstract

A thermoplastic poly urethane can be obtained by a process involving a reaction of a thermoplastic polyester (PE-1) with a diamine (D1), to obtain a composition (Z1) containing an amide (PA-1), and a reaction of the obtained composition (Z1) with an isocyanate composition (I1), containing at least one polyisocyanate, and a polyol composition (P1). The diamine (D1) has a molecular weight in the range from 50 g/mol to 700 g/mol. A process can produce such a thermoplastic polyurethane, and shaped articles can be made containing the thermoplastic polyurethane.

Claims

1: A thermoplastic polyurethane, obtainable or obtained by a process comprising: reacting at least one diamine (D1), having a molecular weight in the range from 50 g/mol to 700 g/mol, with a thermoplastic polyester (PE-1), to obtain an amide (PA-1), and reacting an isocyanate composition (I1) comprising at least one polyisocyanate, the amide (PA-1), and a polyol composition (P1).

2: The thermoplastic polyurethane according to claim 1, wherein the process comprises (i) and (ii): (i) reacting the thermoplastic polyester (PE-1) with the at least one diamine (D1), to obtain a composition (Z1) comprising the amide (PA-1), (ii) reacting the composition (Z1) obtained in (i) with the isocyanate composition (I1) comprising at least one polyisocyanate, and the polyol composition (P1).

3: The thermoplastic polyurethane according to claim 1, wherein the at least one diamine (D1) is selected from the group consisting of compounds of formula (I) or (II): ##STR00022## wherein R1 and R2 are independently of one another selected from the group consisting of O—CH.sub.3, CH.sub.2CH.sub.3, S—CH.sub.3, NH—CH.sub.3, N(CH.sub.3).sub.2, and H, or ##STR00023## wherein a) X.sub.1═X.sub.2═Y.sub.1═Y.sub.2═H, b) X.sub.1═X.sub.2═Y.sub.1═Y.sub.2═CH.sub.3, c) X.sub.1═X.sub.2═Y.sub.1═Y.sub.2=isopropyl, d) X.sub.1═X.sub.2═Y.sub.1═Y.sub.2═C.sub.2H.sub.5, e) X.sub.1═X.sub.2═Y.sub.1═Y.sub.2=butyl, f) X.sub.1═X.sub.2═Y.sub.1═Y.sub.2=tert-butyl, g) X.sub.1═X.sub.2═H and Y.sub.1═Y.sub.2═CH.sub.3, h) X.sub.1═X.sub.2═H and Y.sub.1═Y.sub.2=isopropyl, i) X.sub.1═X.sub.2=Hand Y.sub.1═Y.sub.2═C.sub.2H.sub.5, j) X.sub.1═X.sub.2═H and Y.sub.1═Y.sub.2=butyl, or k) X.sub.1═X.sub.2═H and Y.sub.1═Y.sub.2=tert-butyl; and Z is selected from the group consisting of CH.sub.2, CHCH.sub.3, C(CH.sub.3).sub.2, O, and S.

4: The thermoplastic polyurethane according to claim 1, wherein the at least one diamine (D1) has the formula (III): ##STR00024## wherein R1=R2=S—CH.sub.3 or R1=R2═CH.sub.2CH.sub.3.

5: The thermoplastic polyurethane according to claim 1, wherein the polyol composition (P1) comprises at least one polycarbonate polyol (PC1).

6: The thermoplastic polyurethane according to claim 1, wherein the thermoplastic polyester (PE-1) has a molecular weight in the range from 1500 g/mol to 60000 g/mol.

7: The thermoplastic polyurethane according to claim 1, wherein the thermoplastic polyester (PE-1) is selected from the group consisting of a polyalkylene terephthalate and poly-L-lactic acid.

8: The thermoplastic polyurethane according to claim 1, wherein the thermoplastic polyester (PE-1) has a molecular weight in the range from 1000 g/mol to 5000 g/mol.

9: The thermoplastic polyurethane according to claim 1, wherein the at least one polyisocyanate is selected from the group consisting of methylene diphenyl diisocyanate and an aliphatic diisocyanate.

10: The thermoplastic polyurethane according to claim 1, wherein the thermoplastic polyurethane has a Shore hardness in the range from Shore 45 A to Shore 78 D.

11: A process for producing a thermoplastic polyurethane, the process comprising: reacting at least one diamine (D1), having a molecular weight in the range from 50 g/mol to 700 g/mol, with a thermoplastic polyester (PE-1), to obtain an amide (PA-1), and reacting an isocyanate composition (I1) comprising at least one polyisocyanate, the amide (PA-1), and a polyol composition (P1).

12: The process for producing a thermoplastic polyurethane according to claim 11, the process comprising (i) and (ii): (i) reacting the thermoplastic polyester (PE-1) with the at least one diamine (D1), to obtain a composition (Z1) comprising the amide (PA-1), (ii) reacting the composition (Z1) obtained in (i) with the isocyanate composition (I1) comprising at least one polyisocyanate, and the polyol composition (P1).

13: A shaped article, comprising the thermoplastic polyurethane according to claim 1.

14: The shaped article according to claim 13, wherein the shaped article is selected from the group consisting of a film, a molding, a wheel/roller, a fiber, an automotive trim, a hose, a cable plug, a bellow, a trailing cable, a cable sheathing, a seal, a belt, and a damping element.

15: A shaped article, comprising the thermoplastic polyurethane obtained by the process according to claim 11.

16: The shaped article according to claim 15, wherein the shaped article is selected from the group consisting of a film, a molding, a wheel/roller, a fiber, an automotive trim, a hose, a cable plug, a bellow, a trailing cable, a cable sheathing, a seal, a belt, and a damping element.

Description

EXAMPLES

1. Input Materials

[0276] PC polyol: Polycarbonate polyol [0277] E1195 A: Standard TPU (benchmark), Elastollan 1195 A, thermoplastic polyether-based polyurethane, available from BASF Polyurethanes [0278] 785 A HPM: Standard HPM TPU (Benchmark), Elastollan 785 A HPM, thermoplastic polyether-based polyurethane, available from BASF Polyurethanes [0279] Ethacure 300 dimethylthiotoluenediamine (E300) [0280] Ethacure 100 diethyltoluenediamine (E100)

2. General Production Example

[0281] 2.1 Synthesis is carried out by reactive extrusion in a self-cleaning twin-screw extruder according to the process described in EP1419188B1. The twin-screw extruder having a ratio of screw length to screw diameter of 48 achieves residence times of at least 40 s, preferably more than 60 s. The polymer melt obtained after transamidation and subsequent chain synthesis is processed into pellet materials by underwater or strand pelletization.
2.2 Various samples were investigated in respect of their mechanical properties. Compositions comprising thermoplastic polyurethanes and dimethylthiotoluenediamine/diethyltoluenediamine were produced in a one-shot process or by means of a prepolymer process. [0282] The one-shot process comprised employing all components (diisocyanates (a), polyol (b), chain extender (c) and catalyst (e)) in a first zone of the extruder. The temperature was adjusted to a range from 150° C. to 230° C. at 200 rpm. After commixing of the components and reaction for at least 40 s, preferably at least 60 s, a pellet material was obtained from the polymer melt by strand granulation or underwater pelletization. [0283] The semi-prepolymer process comprised initially employing diisocyanates (a), polyol (b), chain extender (c) and catalyst (e) in a first zone of the extruder. After commixing and pre-reaction of these input materials further chain extender was added in the third or fifth zone. After reaction for at least 40 s, preferably at least 60 s, a pellet material was obtained from the polymer melt by strand pelletization or underwater pelletization.
2.3 Conditions for aging [0284] SI test specimens were stored in a convection oven for the specified time at the appropriate temperature. After the heat treatment they were removed and cooled to room temperature. The mechanical examinations were carried out on the thus-treated samples. [0285] The examination with respect to aging shows that the thermoplastic polyurethanes according to the invention having a different hard segment proportion and produced using dimethylthiotoluenediamine or diethyltoluenediamine were dimensionally stable after storage at 180° C., 190° C. and 200° C. for 6 hours and the flexibility of the material was retained. They moreover retained even more than 50% of their original breaking elongation after storage at 150° C. for 3000 hours. The materials thus meet the requirements of the T4 standard for applications in the automotive sector.

3. Examples

[0286] 3.1 Production of the examples specified hereinbelow was carried out in a ZSK58 MC twin-screw extruder from Coperion, having a processing length of 48 D (12 barrels). The melt was discharged from the extruder by means of a gear pump. After melt filtration the polymer melts were processed by underwater pelletization into pellets which were continuously dried to water contents of below 0.03% in a heated fluidized bed at 60-90° C. [0287] The polybutylene terephthalate Ultradur B4500 from BASF SE was metered into the first zone. Once the PBT had melted the reagent for transamidation, for example Etacure 100, and optionally a catalyst were supplied in the third zone. Once transamidation was complete the further reaction components, such as diisocyanate and polyols, were added in the fifth zone. The addition of further additives was carried out in zone 8. Melt discharging and underwater pelletization were carried out at melt temperatures of 220-230° C. [0288] The barrel temperatures for the feed section, zone 1, are 150° C. Melting and transesterification, zones 2-5, are carried out at temperatures of 250-300° C. Synthesis of the polymer in zones 6-12 is carried out at barrel temperatures of 240-210° C. The screw speed is between 180 and 240 rpm. The throughput is in the range of 180-220 kg/h.

3.2 Compositions

[0289] Example 1 E1195 A with BDO [0290] Example 2 Polycarbonate polyol HPM TPU+E100, (97 A) [0291] Example 3 785 A HPM TPU with BDO [0292] Example 4 Polycarbonate polyol HPM TPU+E100, (92 A) [0293] Example 5 Aliphatic HPM with E100, (86 A) [0294] Beispiel 6 Polycarbonate polyol aromatic TPU+E300

4. Results

[0295] 4.1 Overview of aging characteristics for cable applications (class D):

TABLE-US-00001 Breaking Tensile Aging Aging Aging Aging elongation strength at at at at after before 150° C./ 150° C./ 150° C./ 150° C./ aging aging Sample 3000 h 3000 h 3000 h 3000 h >50% A20 MPa Example 1 − − − − − + Example 2 + + + + + + Example 3 + + − − − +
4.2 Overview of aging characteristics for cable applications (class E, 240° C., 6 hours):

TABLE-US-00002 Breaking elongation before Breaking elongation after Sample aging (%) aging (%) Example 2 430 80 Example 3 620 melted

5. Results after Storage

[0296] 5.1 Storage at 150° C., 3000 hours

TABLE-US-00003 Tensile Breaking strength Breaking elong- before Tensile elongation ation aging strength before aging after Composition Sample (MPa) after aging (%) aging aromatic: HPM Example 4 31 16  40 150 with E100 aromatic HPM Example 2 35 20 430  90 with E100 aliphatic HPM Example 5 16  5 360 110 with E100 785A HPM Benchmark 45 11 620 100
5.2 Storage at 175′ C, 85% R.H., 10 days

TABLE-US-00004 Breaking Tensile elong- Breaking strength Tensile ation elong- before strength before ation aging after aging after Composition Sample (MPa) aging (%) aging E1195A with Standard 55 melted 600 melted BDO reference PC polyol Example 6 13 10 360 200 TPU + Ethacure 300 + MD aromatic HPM Example 4 31 14 450 230 E100 aromatic HPM Example 2 35 16 430 150 with E100 aliphatic (HDI) Example 5 16  3 360  80 HPM with E100 785A HPM mil Benchmark 45 20 620 190 BDO
5.3 Storage at 200° C., 6 hours

TABLE-US-00005 Breaking Tensile elong- Breaking strength Tensile ation elong- before strength before ation aging after aging after Composition Sample (MPa) aging (%) aging E1195A with Standard 55 melted 650 melted BDO Ref Comparison 1 Reference  9 3 680 1020 with E100 1 Comparison 2 Reference 14 7 440 680 with E100 2 Comparison 3 Reference 15 6 360 310 with E100 3 PC polyol Example 6 13 8 360 100 TPU + Ethacure 300 +MDI aromatic: HPM Example 4 31 10 450 300 E100 aromatic HPM Example 2 35 13 430 290 with E100 aliphatic HPM Example 5 16 9 360 190 with E100 785A HPM with Benchmark 45 melted 620 melted BDO
5.4 Storage at 85° C., 85% R.H., 3000 hours

TABLE-US-00006 Tensile Breaking strength Tensile elongation Breaking before strength before elongation Shore Com- aging after aging after hard- position Sample (MPa) aging (%) aging ness aromatic Example 4 31 6 450 80 92A HPM with E100 aromatic Example 2 35 8 430 80 97A HPM with E100 aliphatic Example 5 16 5 360 80 86A HPM with E100 785A Benchmark 45 3 620 30 85A HPM

6. The Following Properties of the Polyurethanes Obtained were Determined by the Methods Specified

[0297] Shore hardness: DIN ISO 7619-1 [0298] Tensile strength and elongation at break: DIN 53504 [0299] Tear propagation resistance: DIN ISO 34-1. B (b) [0300] Abrasion measurement: DIN ISO 4649 [0301] Density: DIN EN ISO 1183-1, A [0302] Compression set DIN ISO 815

CITED LITERATURE

[0303] Kunststoffhandbuch, volume VII, edited by Vieweg and Höchtlen, Carl Hanser Verlag, Munich 1966 (p. 103-113) [0304] EP 1 419 188 B1