Thermoplastic polyurethane

1. A foam bead based on polyurethane, obtained from a polyurethane, wherein the polyurethane is obtained by reacting at least components (i) to (ii):

(i) a polyisocyanate composition; and

(ii) a polyol composition, comprising

(ii.1) a polyester diol or polyether diol having a number-average molecular weight in a range from 500 to 3,000 g/mol, and

(ii.2) a polysiloxane having two terminal isocyanate-reactive functionalities selected from the group consisting of a thio group, a hydroxyl group, and an amino group.

2. The foam bead based on polyurethane according to claim 1 , wherein the polyurethane is obtained by reacting at least components (i) to (iii):

(i) a polyisocyanate composition;

(ii) a polyol composition, comprising

(ii.1) a polyester diol or polyether diol having a number-average molecular weight in a range from 500 to 3,000 g/mol, and

(ii.2) a polysiloxane having two terminal isocyanate-reactive functionalities selected from the group consisting of a thio group, a hydroxyl group, and an amino group; and

(iii) a chain extender composition.

3. The foam bead based on polyurethane according to claim 1 , wherein the polyurethane is obtained by reacting at least components (i) to (iii):

(i) a polyisocyanate composition;

(ii) a polyol composition, comprising

(ii.1) a polyester diol or polyether diol having a number-average molecular weight in a range from 500 to 3,000 g/mol, and

(ii.2) a polysiloxane of formula (I):

 wherein n is an integer in a range from 1 to 250, A and B are independently selected from the group consisting of C 1 -C 20 -alkyl groups;

 X 1 is selected from the group consisting of (CH 2 —CH 2 —O) m group, (CH 2 —CH 2 —CH 2 —O) m group, (CH 2 —CHCH 3 —O) m group, (CH 2 ) m —O group, and (CH 2 ) m group;

 X 2 is selected from the group consisting of (O—CH 2 —CH 2 ) m group, (O—CHCH 3 —CH 2 ) m group, (O—CH 2 —CH 2 —CH 2 ) m group, O—(CH 2 ) m group, and —(CH 2 ) m group;

 wherein m for X 1 and X 2 in each case independently is an integer in a range from 1 to 100; and

 Y 1 , Y 2 are independently selected from the group consisting of a thio group, a hydroxyl group, and an amino group; and

(iii) a chain extender composition.

4. The foam bead based on polyurethane according to claim 3 , wherein n of the polysiloxane as per (ii.2) is an integer in a range from 3 to 50 or in a range from 100 to 240.

5. The foam bead based on polyurethane according to claim 3 , wherein A and B of the polysiloxane as per (ii.2) are independently selected from the group consisting of C 1 - to C 5 -alkyl groups.

6. The foam bead based on polyurethane according to claim 3 , wherein m for X 1 and X 2 of the polysiloxane as per (ii.2) in each case independently is an integer in a range from 1 to 50.

7. The foam bead based on polyurethane according to claim 3 , wherein Y 1 and Y 2 of the polysiloxane as per (ii.2) are both a hydroxyl group or both an amino group.

8. The foam bead based on polyurethane according to claim 3 , wherein X 1 of the polysiloxane as per (ii.2) is a (CH 2 —CH 2 —O) m group, a (CH 2 —CH 2 —CH 2 —O) m group, or a (CH 2 —CHCH 3 —O) m group, X 2 of the polysiloxane as per (ii.2) is an (O—CHCH 3 —CH 2 ) m group, an (O—CH 2 —CH 2 ) m group, or an (O—CH 2 —CH 2 —CH 2 ) m group, wherein m for X 1 and X 2 in each case independently is an integer in a range from 2 to 20; and Y 1 and Y 2 are both a hydroxyl group.

9. The foam bead based on polyurethane according to claim 1 , wherein the polysiloxane as per (ii.2) is present in a proportion in a range from 0.1% to 50% by weight, based on a total weight of all of components (ii.1) and (ii.2).

10. The foam bead based on polyurethane according to claim 2 , wherein the polyurethane has a hard segment content in a range from 10% to 50% by weight, based on a total weight of all of components (i), (ii), and (iii).

11. The foam bead based on polyurethane according to claim 1 , wherein the polyurethane has a hardness in a range from Shore 30 A to 98 A or in a range from Shore 40 D to 64 D.

12. The foam bead based on polyurethane according to claim 1 , wherein the polyurethane is obtained by reacting at least components (i) to (iii):

(i) a diisocyanate composition comprising at least 4,4′-MDI or HDI;

(ii) a polyol composition, comprising

(ii.1) a polyether diol or a polyester diol, wherein the polyether diol or polyester diol has a number-average molecular weight in a range from 500 to 3,000 g/mol, and

(ii.2) a polysiloxane of formula (Ia):

 wherein n is an integer in a range from 10 to 20, A and B are both methyl groups; X 1 is a (CH 2 —CH 2 —O—) m group, X 2 is an (O—CH 2 —CH 2 ) m group, wherein m for X 1 and X 2 in each case independently is an integer in a range from 3 to 15; and

(iii) a chain extender composition comprising at least one diol or diamine selected from the group consisting of butane-1,4-diol, hexane-1,6-diol, ethane-1,2-diol, and 2,4-diamino-3,5-di(methylthio)toluene.

13. The foam bead based on polyurethane according to claim 12 , wherein the polyurethane has a hardness in a range from Shore 30 A to 98 A or in a range from Shore 40 D to 64 D.

14. A process for producing the foam bead according to claim 1 , the process comprising:

melting the polyurethane, thereby obtaining a melted polyurethane,

mixing the melted polyurethane with a blowing agent, thereby forming a blowing agent-containing melt, and

pelletizing the blowing agent-containing melt while foaming at a pressure in a range from 1 to 15 bar.

15. A process for producing the foam bead according to claim 1 , the process comprising:

expanding the polyurethane in a presence of a blowing agent at a pressure in a range from 1 to 15 bar.

16. A bead foam, obtained by fusing the foam bead according to claim 1 by means of water vapor or irradiation with electromagnetic radiation.

17. A bead foam obtained by adhesively bonding the foam beads according to claim 1 .

18. An article, comprising the foam bead according to claim 1 , wherein the article is suitable for applications in fields of sport, clothing, construction, automobiles, and/or electronics.

19. An article, comprising the foam bead according to claim 1 , wherein the article is selected from the group consisting of consumer articles.