Transparent hard thermoplastic polyurethanes

Patent metadata

Field	Value
Publication number	US-12077628-B2
Application number	US-201917252929-A
Country	US
Kind code	B2
Filing date	Jun 18, 2019
Priority date	Jun 19, 2018
Publication date	Sep 3, 2024
Grant date	Sep 3, 2024

Abstract

The present invention relates to a thermoplastic polyurethane obtainable or obtained by reacting a polyisocyanate composition, a chain extender, and a polyol composition, wherein the polyol composition comprises at least one polyol (P1) which has a molecular weight Mw in the range from 500 to 2500 g/mol and has at least one aromatic polyester block (B1), wherein the polyol (P1) includes 20% to 70% by weight of the aromatic polyester blocks (B1), based on the overall polyester polyol (P1). 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, obtained by reacting at least the following components (i) to (iii):
(i) a polyisocyanate composition,
(ii) a chain extender, and
(iii) a polyol composition,
wherein the polyol composition comprises a polyol (P1) having a molecular weight Mw in a range of from 500 to 2500 g/mol and having an aromatic polyester block (B1),
wherein the polyol (P1) comprises 20% to 70% by weight of the aromatic polyester block (B1), based on an overall weight of the polyol (P1), and
wherein the molecular weight Mw is calculated according to the formula:
Mw=1000 mg/g·[( z ·56.106 g/mol)/(OHN [mg/g])],

where z=2,
wherein a hard segment content in the thermoplastic polyurethane is in a range of from 75% to 99%, and
wherein the thermoplastic polyurethane is transparent.

2. The thermoplastic polyurethane of claim 1 , wherein a molar ratio of the chain extender of (ii) to the polyol (P1) present in the polyol composition is in a range from 100:1 to 1:1.

3. The thermoplastic polyurethane of claim 1 , wherein the polyol (P1) comprises 25% to 65% by weight of the aromatic polyester block (B1), based on the overall weight of the polyol (P1).

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

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

6. The thermoplastic polyurethane of claim 1 , wherein the polyol (P1) has a molecular weight Mw in a range of from 500 to 2300 g/mol.

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

8. The thermoplastic polyurethane of claim 1 , wherein a molar ratio of the chain extender of (ii) to the polyol (P1) present in the polyol composition is in a range from 80:1 to 5:1.

9. The thermoplastic polyurethane of claim 1 , wherein the polyol composition comprises a further polyol selected from the group consisting of a polyetherol, a polyesterol, a polycarbonate alcohol and a hybrid polyol.

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

11. A process for producing a shaped body (SC), the process comprising:
(a) preparing a thermoplastic polyurethane, wherein the preparing comprises reacting at least the following components (i) to (iii):
(i) a polyisocyanate composition,
(ii) a chain extender, and
(iii) a polyol composition,
wherein the polyol composition comprises a polyol (P1) having a molecular weight Mw in a range of from 500 to 2500 g/mol and having an aromatic polyester block (B1),
wherein the polyol (P1) comprises 20% to 70% by weight of the aromatic polyester block (B1), based on an overall weight of the polyol (P1), and
wherein the molecular weight (Mw) is calculated according to the formula:
Mw=1000 mg/g·[( z ·56.106 g/mol)/(OHN [mg/g])],

where z=2,
wherein a hard segment content in the thermoplastic polyurethane is in a range of from 75% to 99%, and wherein the thermoplastic polyurethane is transparent; and
(b) producing a shaped body (SC) from the thermoplastic polyurethane.

12. The process of claim 11 , wherein the shaped body (SC) is produced in (b) by extrusion, injection molding or sintering methods or from solution.

13. A shaped body, obtained by the process of claim 11 .

14. The shaped body of claim 13 , wherein the shaped body is a film.

Assignees

• Basf Se

Inventors

• Richter Sebastian
• Tomovic Zeljko
• Zarbakhsh Sirus

Classifications

• C08J5/18

  Manufacture of films or sheets · CPC title

• C08G18/7671 Primary

  containing only one alkylene bisphenyl group · CPC title

• C08G18/664 Primary

  with compounds of group C08G18/3203 · CPC title

• C08G18/4216

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

• C08G18/4213

  from terephthalic acid and dialcohols · CPC title