Polymer and organic electronic device

1. A composition comprising a polymer and a phosphorescent material wherein the polymer comprises repeat units of formula (III):

wherein:

R 1 in each occurrence is independently C 1-40 hydrocarbyl, —OR 11 , —SR 11 , —NR 11 2 , or —SiR 11 3 ; R 11 each occurrence is C 1-40 hydrocarbyl;

R 2 is a C 1-40 hydrocarbyl; and

n is 0, 1, 2, 3 or 4.

2. The composition according to claim 1 , wherein the polymer comprises one or more co-repeat units.

3. The composition according to claim 2 , wherein the polymer comprises an arylene co-repeat unit that may be unsubstituted or substituted with one or more substituents.

4. The composition according to claim 2 , wherein the one or more co-repeat units include a conjugation-breaking repeat unit that does not provide any conjugation path between repeat units adjacent to the conjugation-breaking repeat unit.

5. The composition according to claim 4 , comprising one or more co-repeat units of formula (II):

wherein:

Ar 1 in each occurrence independently represent an aryl or heteroaryl group that may be unsubstituted or substituted with one or more substituents; and

Sp represents a spacer group comprising at least one carbon or silicon atom.

6. The composition according to claim 1 , wherein the phosphorescent material is mixed with the polymer.

7. The composition according to claim 1 , wherein the phosphorescent material is covalently bound to the polymer.

8. The composition according to claim 1 , wherein the phosphorescent material has a photoluminescent spectrum with a peak in the range of 420-490 nm.

9. A formulation comprising the composition according to claim 1 and at least one solvent.

10. An organic light-emitting device comprising an anode, a cathode and a light-emitting layer between the anode and cathode wherein the light-emitting layer comprises the composition according to claim 1 .

11. A polymer comprising a repeat unit of formula (III):

wherein:

R 2 is a C 1-40 hydrocarbyl;

R 1 in each occurrence is independently C 1-40 hydrocarbyl, —OR 11 , —SR 11 , —NR 11 2 , or —SiR 11 3 ; R 11 each occurrence is C 1-40 hydrocarbyl; and

n is 0, 1, 2, 3 or 4.

12. The composition of claim 1 , wherein the polymer further comprises a repeat unit of formula:

wherein q is 0, 1, 2, 3 or 4 and R 3 independently in each occurrence is selected from the group consisting of:

alkyl, wherein one or more non-adjacent C atoms may be replaced with optionally substituted aryl or heteroaryl, O, S, substituted N, C═O or —COO—, and one or more H atoms may be replaced with F;

aryl or heteroaryl groups that may be unsubstituted or substituted with one or more C 1-20 alkyl groups;

a group of formula —(Ar 3 ) r wherein each Ar 3 is independently an aryl or heteroaryl group and r is at least 2, wherein each Ar 3 may be unsubstituted or substituted with one or more C 1-20 alkyl groups; and

a crosslinkable-group.

13. The composition according to claim 1 , wherein the polymer does not comprise a fluorene repeat unit.

14. The polymer according to claim 11 , wherein R 2 is an aromatic ring or a branched or linear chain of aromatic rings, wherein each ring may be unsubstituted or substituted with one or more substituents R 4 , wherein each R 4 is independently a C 1-20 alkyl, wherein one or more non-adjacent C atoms of the C 1-20 alkyl may be replaces with O or S, and one or more H atoms of the C 1-20 alkyl may be replaced with F.

15. The polymer according to claim 11 , wherein the polymer further comprises a repeat unit of formula (IX):

wherein;

Ar 8 and Ar 9 in each occurrence are independently selected from subsutitited or unsubstituted aryl or heteroaryl;

g is greater than or equal to 1;

R 13 is H or a substituent ; and

c and d are each independently 1, 2 or 3.

16. The polymer of claim 11 , wherein the polymer further comprises a repeat unit of formula

wherein q is 0, 1, 2, 3 or 4 and R 3 independently in each occurrence is selected from the group consisting of:

alkyl, wherein one or more non-adjacent C atoms may be replaced with optionally substituted aryl or heteroaryl, O, S, substituted N, C═O or —COO—, and one or more H atoms may be replaced with F;

aryl or heteroaryl groups that may be unsubstituted or substituted with one or more C 1-20 alkyl groups;

a group of formula —(Ar 3 ) r wherein each Ar 3 is independently an aryl or heteroaryl group and r is at least 2, wherein each Ar 3 may be unsubstituted or substituted with one or more C 1-20 alkyl groups; and

a crosslinkable-group.

17. The polymer according to claim 11 , wherein the polymer does not comprise a fluorene repeat unit.

18. A method of forming a polymer comprising the step of polymerising a monomer of formula (IV):

wherein LG is a leaving group capable of leaving in a coupling reaction to form a carbon-carbon bond with an aromatic or heteroaromatic group, and wherein

R 1 , R 2 and n are as defined in claim 1 .

19. The method according to claim 18 , wherein each LG is independently selected from the group consisting of halogens, boronic acids; boronic esters; sulfonic acids; and sulfonic esters.

20. The method according to claim 19 , wherein the polymerization is carried out in the presence of a metal catalyst.