Star-shaped and triblock polymers with enhanced crosslinkability

1. A composition, comprising:

a) at least one polymer consisting of one polymer block A and at least two polymer blocks B; and

b) at least one crosslinking agent carrying at least two azide groups

wherein:

each polymer block B is attached to the polymer block A, and at least 60 mol % of the monomer units of polymer block B are selected from the group consisting of:

and

R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 are independently and at each occurrence H or C 1-4 -alkyl,

wherein the weight ratio of polymer block A/total polymer blocks B is from 70/30 to 96/4 and the polymers have a number average molecular weight Mn of at least 60000 g/mol and a weight average molecular weight Mw of at least 70000 g/mol, both as determined by gel permeation chromatography,

with the proviso that at least one of the monomer units (1A) and (1B) is present, and that the ratio of [mols of monomer units (1A) and (1B)]/[mols of monomer units (1A), (1B), (1C) and (1D)] is at least 30%.

2. The composition of claim 1 , wherein:

at least 70 mol % of the monomer units of the polymer block B are selected from the group consisting of:

 and

R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are independently and at each occurrence H or C 1-4 -alkyl.

3. The composition of claim 1 , wherein:

at least 80 mol % of the monomer units of the polymer block B are selected from the group consisting of:

 and

R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are H.

4. The composition of claim 1 , wherein:

at least 80 mol % of the monomer units of polymer block A are selected from the group consisting of:

R 20 , R 21 , R 22 , R 23 , R 24 , R 25 and R 26 are independently and at each occurrence selected from the group consisting of H, C 6-14 -aryl, 5 to 14 membered heteroaryl and C 1-30 -alkyl;

R a is C(O)OH, C(O)OC 1-30 -alkyl, C(O)—H, C(O)C 6-14 -aryl, C(O)N(C 1-30 -alkyl) 2 , C(O)N(C 6-14 -aryl) 2 , C(O)N(C 1-30 -alkyl)(C 6-14 -aryl), C(O)—C 6-14 -aryl, C(O)—C 1-30 -alkyl, O—C 6-14 -aryl, O—C 1-30 -alkyl, OC(O)C 1-30 -alkyl, OC(O)C 6-14 -aryl or CN;

C 6-14 -aryl and 5-14 membered heteroaryl can be substituted with one or more substituents selected from the group consisting of C 1-10 -alkyl, C(O)OH, C(O)OC 1-10 -alkyl, C(O)phenyl, C(O)N(C 1-10 -alkyl) 2 , C(O)N(phenyl) 2 , C(O)N(C 1-10 -alkyl)(phenyl), C(O)-phenyl, C(O)—C 1-10 -alkyl, OH, O-phenyl, O—C 1-10 -alkyl, OC(O)C 1-10 -alkyl, OC(O)-phenyl and CN and NO 2 ;

C 1-30 -alkyl can be substituted with one or more substituents selected from the group consisting of with phenyl, C(O)OH, C(O)OC 1-10 -alkyl, C(O)phenyl, C(O)N(C 1-10 -alkyl) 2 , C(O)N(phenyl) 2 , C(O)N(C 1-10 -alkyl)(phenyl), C(O)-phenyl, C(O)—C 1-10 -alkyl, O-phenyl, O—C 1-10 -alkyl, OC(O)C 1-10 -alkyl, OC(O)-phenyl, Si(C 1-10 -alkyl) 3 , Si(phenyl) 3 and CN and NO 2 ;

n is an integer from 1 to 3; and

L 20 is C 1-10 -alkylene, C 2-10 -alkenylene, C 2-10 -alkynylene, C 6-14 -arylene or S(O).

5. The composition according to claim 1 , wherein:

at least 80 mol % of the monomer units of polymer block A are selected from the group consisting of:

R 20 , R 21 and R 22 are independently selected from the group consisting of H, C 6-14 -aryl, 5 to 14 membered heteroaryl and C 1-30 -alkyl;

R a is C(O)OC 1-30 -alkyl;

C 6-14 -aryl and 5-14 membered heteroaryl can be substituted with one or more C 1-10 -alkyl;

C 1-30 -alkyl can be substituted with one or more substituents selected from the group consisting of Si(C 1-10 -alkyl) 3 and Si(phenyl) 3 ;

n is an integer from 1 to 3; and

L 20 is C 1-10 -alkylene or C 6-14 -arylene.

6. The composition of claim 1 , wherein:

at least 90 mol % of the monomer units of polymer block A is a monomer unit selected from the group consisting of:

R 20 and R 21 are independently selected from the group consisting of H and C 6-14 -aryl;

C 6-14 -aryl can be substituted with one or more C 1-10 -alkyl; and

L 20 is C 6-14 -arylene.

7. The composition of claim 1 , wherein:

the crosslinking agent carrying at least two azide groups is of formula:

a is 0 or 1;

R 50 is at each occurrence selected from the group consisting of H, halogen, SO 3 M and C 1-20 -alkyl, which C 1-20 -alkyl can be substituted with one or more halogen, wherein M is H, Na, K or Li; and

L 50 is a linking group.

8. The composition of claim 7 , wherein:

L 50 is a linking group of formula:

b, c, d, e, f, g and h are independently from each other 0 or 1, provided that b, c, d, e, f, g and h are not all at the same time 0;

W 1 , W 2 , W 3 and W 4 are independently selected from the group consisting of C(O), C(O)O, C(O)—NR 51 , SO 2 —NR 51 , NR 51 , N + R 51 R 51 , CR 51 ═CR 51 and ethynylene;

R 51 is at each occurrence H or C 1-10 -alkyl, or two R 51 groups, which can be from different W 1 , W 2 , W 3 and W 4 groups, together with the connecting atoms form a 5, 6 or 7 membered ring, which may be substituted with one to three C 1-6 -alkyl;

Z 1 , Z 2 and Z 3 are independently selected from the group consisting of C 1-10 -alkylene, C 5-8 -cycloalkylene, C 6-14 -arylene, 5 to 14 membered heteroarylene, and polycyclic system containing at least one ring selected from C 6-14 -aromatic ring and 5 to 14 membered heteroaromatic ring; and

C 1-10 -alkylene, C 5-8 -cycloalkylene, C 6-14 membered arylene, 5 to 14 membered heteroarylene and polycyclic system containing at least one ring selected from C 6-14 -aromatic ring and 5 to 14 membered heteroaromatic ring substituted with one to five C 1-20 -alkyl or phenyl.

9. The composition of claim 1 , further comprising a solvent.

10. The composition of claim 8 , wherein the composition is a solution and comprises;

i) 0.1 to 500 mg of the at least one polymer based on 1000 mg of the composition;

ii) 0.1 to 20% by weight of the at least one crosslinking agent carrying at least two azide groups based on the weight of the one or more polymers; and

iii) a solvent.

11. A cured layer formed from the composition of claim 1 .

12. An electronic device, comprising the cured layer of claim 11 .

13. The electronic device of claim 12 , wherein:

the electronic device is an organic field effect transistor; and

the layer is the dielectric layer.