Arylcyclobutenes

1. A polymer comprising as polymerized units one or more arylcyclobutene first monomers and one or more second monomers having two or more dienophilic moieties and one or more acid moieties chosen from carboxylic acid, protected carboxylic acid, and sulfonic acid; wherein the protected carboxylic acid is an ester having a quaternary carbon bonded directly to the alkoxy oxygen of the ester group; and wherein the one or more second monomers are free of benzocyclobutene moieties.

2. The polymer of claim 1 wherein the one or more arylcyclobutene first monomers further comprises one or more moieties chosen from carboxylic acid, protected carboxylic acid and sulfonic acid; wherein the protected carboxylic acid is an ester having a quaternary carbon bonded directly to the alkoxy oxygen of the ester group.

3. The polymer of claim 1 further comprising two distinct arylcyclobutene first monomers.

4. The polymer of claim 1 wherein the dienophilic moieties are chosen from ethylenically unsaturated and acetylenically unsaturated carbon-carbon bonds.

5. The polymer of claim 1 further comprising as polymerized units one or more third monomers comprising one or more diene or dienophilic moieties.

6. The polymer of claim 1 wherein the one or more arylcyclobutene first monomers have the formula:

wherein B 1 is an m-valent linking group; Ar is a polyvalent aryl group and the carbon atoms of the cyclobutene ring are bonded to adjacent carbon atoms on the same aromatic ring of Ar; m is an integer of 1 or more; n is an integer of 1 or more; each of R 1 and R 2 is independently a monovalent group; the two R 1 moieties may be taken together along with the carbon to which they are attached to form a carbonyl or thiocarbonyl; and the two R 2 moieties may be taken together along with the carbon to which they are attached to form a carbonyl or thiocarbonyl.

7. The polymer of claim 1 wherein the one or more second monomers have the formula

(A) p -Z(E) q

wherein each A is independently an organic residue having from 1 to 20 carbon atoms and a one or more moieties chosen from carboxylic acid, protected carboxylic acid and sulfonic acid; each E is independently an organic residue having from 2 to 20 carbon atoms and one or more dienophilic moieties; Z is a chemical bond or an organic residue having from 1 to 30 carbon atoms; p is an integer from 1 to 6; and q is an integer from 2 to 6; wherein the protected carboxylic acid is an ester having a quaternary carbon bonded directly to the alkoxy oxygen of the ester group.

8. The polymer of claim 7 wherein p is an integer from 1 to 4.

9. The polymer of claim 7 wherein q is an integer from 2 to 4.

10. A composition comprising the polymer of claim 1 and one or more organic solvents.

11. The composition of claim 10 further comprising one or more photoactive compounds.

12. A method of forming a film on a substrate comprising: providing a substrate; coating a layer of a composition of claim 10 on a surface of the substrate; and curing the coating.

13. The polymer of claim 1 wherein at least one second monomer is chosen from formulae (6) to (9):

wherein each R 17 is independently chosen from C 3-10 alkenyl; R 18 is chosen from C 1-10 alkyl, C 3-10 alkenyl, and —OR 15 ; and R 19 is chosen from C 2-10 alkyl and C 2-10 alkenyl;

wherein each R 20 is independently chosen from C 3-10 alkenyl and C 1-10 alkyl-(O—C 3-10 alkenyl) z ; x and y are independently 1 or 2; and z is an integer of 1-3; provided that y=2 when R 20 is C 3-10 alkenyl; and

wherein each R 21 is independently chosen from H and C 1-10 alkyl; each R 22 is independently C 2-20 alkenyl, each R 23 is chosen from C 2-10 alkyl and C 2-10 alkenyl.

14. A polymer comprising as polymerized units one or more arylcyclobutene first monomers of the formula:

wherein B 1 is an m-valent linking group; Ar is a polyvalent aryl group and the carbon atoms of the cyclobutene ring are bonded to adjacent carbon atoms on the same aromatic ring of Ar; m is an integer of 1 or more; n is an integer of 1 or more; each of R 1 and R 2 is independently a monovalent group; the two R 1 moieties may be taken together along with the carbon to which they are attached to form a carbonyl or thiocarbonyl; and the two R 2 moieties may be taken together along with the carbon to which they are attached to form a carbonyl or thiocarbonyl, and one or more second monomers of the formula

(A) p -Z(E) q

wherein each A is independently an organic residue having from 1 to 20 carbon atoms and a moiety chosen from carboxylic acid, protected carboxylic acid and sulfonic acid; each E is independently an organic residue having from 2 to 20 carbon atoms and one or more dienophilic moieties; Z is a chemical bond or an organic residue having from 1 to 30 carbon atoms; p is an integer from 1 to 6; and q is an integer from 2 to 6; wherein wherein the protected carboxylic acid is an ester having a quaternary carbon bonded directly to the alkoxy oxygen of the ester group; and wherein the one or more second monomers are free of benzocyclobutene moieties.

15. The polymer of claim 14 wherein the dienophilic moieties comprise one or more of ethylenic unsaturation (double bond) and acetylenic unsaturation (triple bond).

16. The polymer of claim 14 wherein at least one second monomer is chosen from formulae (6) to (9):

wherein each R 17 is independently chosen from C 3-10 alkenyl; R 18 is chosen from C 1-10 alkyl, C 3-10 alkenyl, and —OR 15 ; and R 19 is chosen from C 2-10 alkyl and C 2-10 alkenyl;

wherein each R 20 is independently chosen from C 3-10 alkenyl and C 1-10 alkyl-(O—C 3-10 alkenyl) z ; x and y are independently 1 or 2; and z is an integer of 1-3; provided that y=2 when R 20 is C 3-10 alkenyl; and

wherein each R 21 is independently chosen from H and C 1-10 alkyl; each R 22 is independently C 2-20 alkenyl, each R 23 is chosen from C 2-10 alkyl and C 2-10 alkenyl.