Thermoplastic polyurethane composition with high mechanical properties, good resistance against UV radiation and low blooming and fogging

Abstract

A composition contains thermoplastic polyurethane, which is the reaction product of a pentamethylene diisocyanate, a polycarbonate diol, and a chain extender. The composition is useful for producing articles. A production process for producing a filled composition involves adding glass to the composition. Articles can be derived from the composition and the filled composition.

Claims

1. A composition comprising: thermoplastic polyurethane, which is a reaction product of the following components; i. diisocyanate, ii. compound reactive toward isocyanate, and iii. chain extender wherein the diisocyanate is pentamethlyene diisocyanate and the compound reactive toward isocyanate comprises polycarbonate diol.

2. The composition according to claim 1, wherein the chain extender comprises ethanediol, 1,3-propanediol, 1,4-butanediol, or 1,6-hexanediol, or comprises a mixture thereof.

3. The composition according to claim 1, wherein the composition has a hardness of less than 95 Shore A, determined according to DIN ISO 7619-1: 2016.

4. The composition according to claim 1, wherein the composition further comprises an additive.

5. The composition according to claim 4, wherein the additive is glass and wherein the glass is in form of a fiber or a sphere.

6. The composition according to claim 1, wherein the isocyanate, the polycarbonate diol, or the chain extender, or a mixture thereof is bio-based.

7. A method comprising: producing an article with the composition according to claim 1, by injection moulding, calendering, powder sintering, or extrusion.

8. A process for the production of a filled composition the process comprising: adding glass to the composition according to claim 1.

9. An article, produced from the composition according to claim 1.

10. The composition according to claim 2, wherein the chain extender comprises 3-propanediol, 1,4-hutanediol, or a mixture thereof.

11. The composition according to claim 3, wherein the composition has a hardness of less than 85 Shore A, determined according to DIN ISO 7619-1: 2016.

12. The composition according to claim 4, wherein the additive is glass.

13. The composition according to claim 6, wherein the isocyanate is bio-based

14. An article, produced from the filled composition obtained by the process according to claim 8.

Description

Example 2 Preparation of Polymers by Hand Casting

[0124] The polyols were placed in a container at 80° C. and mixed with the components according to the amounts given above under vigorous stirring in a reaction vessel. The isocyanate was added at last component. As soon as a reaction temperature of 110° C. was reached or the foam-level exceeded 80% of the reaction vessel volume. The reaction mixture was poured on a heating plate (120° C.) forming a slab. The slab was cured onto the plate for 10 min, afterwards tempered at 80° C. for 15 h, crushed and extruded into granules.

[0125] The extrusion was carried out on a twin-screw extruder with a strand diameter of approx. 2 mm. Extruder: co-rotating twin screw extruder, APV MP19

[0126] Temperature profile: [0127] Heating zone HZ1 (feeding zone) 175° C. to 185° C. [0128] Heating zone HZ2 180° C. to 190° C. [0129] Heating zone HZ3 185° C. to 195° C. [0130] Heating zone HZ4 185° C. to 195° C. [0131] Heating zone HZ5 (nozzle) 180° C. to 190° C. [0132] Screw speed: 100 rpm [0133] Pressure: approx. 10 to 30 bar [0134] Strand cooling: Water bath (10° C.)

[0135] The obtained granulate was reshaped by injection molding into 2 mm thick test plates. The temperature of the melt during the production of the test plates did not exceed 250° C.

Example 3: Description of the Storage Testing

[0136] Deposits on the surface (blooming) are unacceptable for many applications. Storage tests can help to predict whether deposits will be formed or not.

[0137] Storage test 1: The specimens, heated at 100° C. for 20 h were stored under standard conditions of temperature and humidity (23° C., 50% r.h.).

[0138] Storage test 2: The unheated specimens were stored under standard conditions of temperature and humidity (23° C., 50% r.h.).

[0139] Storage test 3: The specimens, heated at 100° C. for 20 h were stored in an oven at 80° C.

[0140] Storage test 4: The unheated specimens were stored in an oven at 80° C.

Example 4: Results of the Storage Testing

[0141]

TABLE-US-00001 1 2 3 4 5 6 7 8 9 10 11 TPU (VB (VB) (VB) (EB) (EB) (EB) (EB) (EB) (EB) (EB) (EB) Shore Hardness 90 90 80 90 90 80 90 95 88 90 90 Polyesterol 2000 X X PTHF 1000 X X X X X X X X Eternacoll PH 200D X 1,4-Butanediol mol- 100 100 100 100 100 100 100 100 100 85 100 1,3-Propanediol mol- 0 0 0 0 0 0 0 0 0 15 0 % PDI X X X X X X X X HDI X X X Chopvantage HP3550 % 10 20 EC10-3,8 (glas fiber) iMK16 % 10 (glas bubbles Storage test 1 21 d D. D. D. W. D. W.D. W. D. W. D. W. D. W. D. W. D. W. D. Storage test 1 42 d D. D. D. W. D. W. D. W. D. W. D. W. D. W. D. W. D. W. D. Storage test 2 21 d D. D. D. W. D. W. D. W. D. W. D. W. D. W. D. W. D. W. D. Storage test 2 42 d D. D. D. W.D. W. D. W. D. W. D. W. D. W. D. W. D. W. D. Storage test 3 21 d D. D. D. W. D. W. D. W. D. W. D. W. D. W. D. W. D. W. D. Storage test 3 42 d D. D. D. D. D. W. D. W. D. W. D. W. D. W. D. W. D. Storage test 4 21 d D. D. D. W. D. W. D. W. D. W. D. W. D. W. D. W. D. W. D. Storage test 4 42 d D. D. D. D. D. W. D. W. D. W. D. W. D. W. D. W. D: D.: deposit W. D.: without deposit

[0142] TPU 1-2 (comparative example VB) are based on HDI with a hardness of 90 Shore A. All storage tests show deposits.

[0143] TPU 3 (VB) is based on HDI with a reduced Shore hardness of 80A. All storage tests show deposits.

[0144] TPU 4-5 (inventive example EB) are based on PDI with a hardness of 90 Shore A and show reduced blooming compared to TPU 1-3.

[0145] TPU 6 (EB) is based on PDI with a hardness of 80 Shore A. The reduced hardness compared to TPU 4 and 5 results in a further reduced blooming.

[0146] TPU 7-9 (EB) are based on TPU 6. Fillers (glass fiber and glass bubbles) were added to increase the hardness. TPU 7-9 have an increased Shore hardness of 90 Shore A but show reduced blooming compared to TPU 1 and 2.

[0147] TPU 10 (EB) is based on PDI with a hardness of 90 Shore A. In comparison to TPU 5 this TPU is based on a mixture of chain extenders. TPU 10 shows reduced blooming, compared to TPU 5.

[0148] TPU 11 (EB) are based on PDI and with a hardness of 90 Shore A. In comparison to TPU 5 this TPU is based on a polycarbonate polyol. TPU 11 shows reduced blooming, compared to TPU 5.