Hard transparent thermoplastic polyurethane

Patent metadata

Field	Value
Publication number	US-11414543-B2
Application number	US-201716349798-A
Country	US
Kind code	B2
Filing date	Dec 22, 2017
Priority date	Dec 23, 2016
Publication date	Aug 16, 2022
Grant date	Aug 16, 2022

Abstract

The present invention relates to a thermoplastic polyurethane obtainable or obtained by converting a polyisocyanate composition, a one chain extender, and a polyol composition, wherein the polyol composition comprises a polyol (P1) which has a molecular weight Mw in the range from 500 to 2000 g/mol and has at least one aromatic polyester block (B1), wherein the hard segment content in the thermoplastic polyurethane is <75%. The present invention further relates to a process for producing a shaped body comprising such a thermoplastic polyurethane, and to shaped bodies obtainable or obtained by a process of the invention.

First claim

The invention claimed is:

1. A thermoplastic polyurethane, comprising, in reacted form:
a polyisocyanate;
a chain extender; and
a polyol (P1),
wherein the thermoplastic polyurethane is obtained by polymerizing a mixture comprising (i) a polyisocyanate composition, (ii) the chain extender, and (iii) a polyol composition comprising: the polyol (P1), which has a molecular weight Mw in a range of from 500 to 2000 g/mol, and comprises an aromatic polyester block (B1),
the polyol (P1) is prepared here by reacting the aromatic polyester with dicarboxylic acids and diols and the aromatic polyester used has a higher molecular weight than the blocks (B1) present in the polyol (P1), and
a hard segment content in the thermoplastic polyurethane is<75%.

2. The polyurethane of claim 1 , wherein the polyester polyol (P1) comprises 20 to 70 wt. % of the aromatic polyester block (B1), based on an overall weight of polyester polyol (P1).

3. The polyurethane of claim 1 , wherein the aromatic polyester block (B1) is a polyester of an aromatic dicarboxylic acid and an aliphatic diol.

4. The polyurethane of claim 1 , wherein the aromatic polyester block (B1) is a polybutylene terephthalate block.

5. The polyurethane of claim 1 , wherein the aromatic polyester block (B1) is a polyethylene terephthalate block.

6. The polyurethane of claim 1 , wherein the polyol (P1) has a molecular weight Mw in a range of from 750 to 1500 g/mol.

7. The polyurethane of claim 1 , wherein the chain extender is a diol having a molecular weight <220 g/mol.

8. The polyurethane of claim 1 , wherein the chain extender and the polyol (P1) are present in the polyol composition in a molar ratio in a range of from 40:1 to 1:10.

9. The polyurethane of claim 1 , wherein the polyol composition further comprises a second polyol which is a polyetherol, a polyesterol, a polycarbonate alcohol, or a hybrid polyol.

10. The polyurethane of claim 1 , wherein the polyisocyanate is an aliphatic diisocyanate.

11. The polyurethane of claim 1 , wherein the hard segment content in the thermoplastic polyurethane is in a range of from 10% to 75%.

12. A process for producing a shaped body, the process comprising:
(a) preparing a thermoplastic polyurethane comprising, in reacted form, (i) polyisocyanate composition; (ii) a chain extender; and (iii) a polyol composition, the polyol composition comprising a polyol (P1) having a molecular weight Mw in a range of from 500 to 2000 g/mol and comprising an aromatic polyester block (B1), and a hard segment content in the thermoplastic polyurethane being<75%,
wherein the polyol (P1) is prepared here by reacting the aromatic polyester with dicarboxylic acids and diols and the aromatic polyester used has a higher molecular weight than the blocks (B1) present in the polyol (P1): and
(b) producing a shaped body from the thermoplastic polyurethane.

13. The process of claim 12 , wherein the producing comprises extruding, injection molding, sintering, or solution processing the polyurethane to form the shaped body.

14. A shaped body, obtained by the process of claim 12 .

15. The shaped body of claim 14 , which is a consumer article.

16. The shaped body of claim 15 , wherein the consumer article is a toothbrush, a razor, a domestic article housing , a display, a computer part, a phone part, a plug, an automobile interior trim part, or a footwear part.

17. The polyurethane of claim 1 , wherein the polyisocyanate is an aromatic diisocyanate.

18. The polyurethane of claim 1 , wherein the hard segment content in the thermoplastic polyurethane is in a range of from 29.2% to 60%.

19. The polyurethane of claim 1 , wherein the polyol (P1) has an acid number<1 mg KOH/g.

20. The polyurethane of claim 1 , having an elongation at break in a range of over 300% to 410%.

21. The polyurethane of claim 1 , wherein a number of repeat units in an aromatic system is greater than 2 in series.

Assignees

• Basf Se

Inventors

• Tomovic Zeljko
• Richter Sebastian
• Schaefer Frank

Classifications

• C08G18/3206 Primary

  aliphatic · CPC title

• C08G18/4216 Primary

  from mixtures or combinations of aromatic dicarboxylic acids and aliphatic dicarboxylic acids and dialcohols · CPC title

• C08G18/425

  the polyols containing one or two ether groups · CPC title

• C08G18/664 Primary

  with compounds of group C08G18/3203 · CPC title

• C08G2140/00

  Compositions for moulding powders · CPC title