POLY(IMIDE-AMIDE) COPOLYMER, A METHOD FOR PREPARING A POLY(IMIDE-AMIDE) COPOLYMER, AND AN ARTICLE INCLUDING A POLY(IMIDE-AMIDE) COPOLYMER

1 . A poly(imide-amide) copolymer, which is a product of a reaction between a diamine comprising an amide structural unit-containing oligomer represented by Chemical Formula 1 and a dianhydride represented by Chemical Formula 3:

wherein, in Chemical Formula 1,

R 1 and R 2 are the same or different, and are each independently selected from a halogen, a hydroxyl group, a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C6 to C20 aryl group, or a substituted or unsubstituted C1 to C10 alkoxy group,

n0 is equal to or greater than 1,

n1 and n2 are the same or different, and are each independently an integer from 0 to 4, provided that n1+n2 is an integer ranging from 0 to 4, and

Ar 1 and Ar 2 are the same or different and are each independently represented by Chemical Formula 2:

wherein, in Chemical Formula 2,

R 6 and R 7 are the same or different and are each independently an electron withdrawing group selected from —CF 3 , —CCl 3 , —CBr 3 , —Cl 3 , —NO 2 , —CN, —C(═O)CH 3 , and —CO 2 C 2 H 5 ,

R 8 and R 9 are the same or different and are each independently a halogen, a hydroxyl group, a substituted or unsubstituted C1 to C10 aliphatic group, a substituted or unsubstituted C6 to C20 aromatic group, an alkoxy group of formula —OR 204 , wherein R 204 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 205 R 206 R 207 , wherein R 205 , R 206 , and R 207 are the same or different and are each independently a hydrogen or a C1 to C10 aliphatic organic group, and

n3 is an integer from 1 to 4, n5 is an integer from 0 to 3, provided that n3+n5 is an integer ranging from 1 to 4,

n4 is an integer from 1 to 4, n6 is an integer from 0 to 3, provided that n4+n6 is an integer ranging from 1 to 4;

wherein, in Chemical Formula 3,

R 10 is a single bond, or a substituted or unsubstituted C1 to C30 aliphatic group, a substituted or unsubstituted C3 to C30 alicydic organic group, a substituted or unsubstituted C6 to C30 aromatic organic group, or a substituted or unsubstituted C2 to C30 heterocylic group,

R 12 and R 13 are the same or different and are each independently a halogen, a hydroxyl group, a substituted or unsubstituted C1 to C10 aliphatic group, a substituted or unsubstituted C6 to C20 aromatic group, an alkoxy group of formula —OR 205 , wherein R 205 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 209 R 210 R 211 , wherein R 209 , R 210 , and R 211 are the same or different and are each independently a hydrogen or a C1 to C10 aliphatic organic group, and

n7 and n8 are the same or different and are each independently an integer ranging from 0 to 3.

2 . The poly(imide-amide) copolymer according to claim 1 , wherein the diamine further comprises a diamine compound represented by Chemical Formula A:

H 2 N—Ar 3 —NH 2   Chemical Formula A

wherein in Chemical Formula A,

Ar 3 is represented by the above Chemical Formula 2;

wherein, in Chemical Formula 2,

R 6 and R 7 are the same or different and are each independently an electron withdrawing group selected from —CF 3 , —CCl 3 , —CBr 3 , —Cl 3 , —NO 2 , —CN, —C(═O)CH 3 , and —CO 2 C 2 H 5 ,

R 8 and R 9 are the same or different and are each independently a halogen, a hydroxyl group, a substituted or unsubstituted C1 to C10 aliphatic group, a substituted or unsubstituted C6 to C20 aromatic group, an alkoxy group of formula —OR 204 , wherein R 204 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 205 R 206 R 207 , wherein R 205 , R 206 , and R 207 are the same or different and are each independently a hydrogen or a C1 to C10 aliphatic organic group, and

n3 is an integer from 1 to 4, n5 is an integer from 0 to 3, provided that n3+n5 is an integer ranging from 1 to 4,

n4 is an integer from 1 to 4, n6 is an integer from 0 to 3, provided that n4+n6 is an integer ranging from 1 to 4.

3 . The poly(imide-amide) copolymer according to claim 1 , wherein the dianhydride represented by Chemical Formula 3 is represented by Chemical Formula 4, Chemical Formula 5, or a combination thereof:

wherein, in Chemical Formulae 4 and 5,

R 12 and R 13 are the same or different, and are independently a halogen, a hydroxy group, a substituted or unsubstituted C1 to C10 aliphatic organic group, a C6 to C20 aromatic organic group, an alkoxy group of formula —OR 208 , wherein R 208 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 209 R 210 R 211 , wherein R 209 , R 210 , and R 211 are the same or different, and are each independently hydrogen or a C1 to C10 aliphatic organic group, and

n7 and n8 are each independently integers ranging from 0 to 3.

4 . The poly(imide-amide) copolymer according to claim 1 , wherein a content of the amide structural unit derived from the amide structural unit-containing oligomer is equal to or greater than about 20 mole percent to about 70 mole percent based on the total mole number of the amide structural unit derived from the oligomer and the imide group derived from the Chemical Formula 3.

5 . The poly(imide-amide) copolymer according to claim 1 , wherein a content of the amide structural unit derived from the amide structural unit-containing oligomer is equal to or greater than about 50 mole percent to about 70 mole percent based on the total mole number of the amide structural unit derived from the oligomer and the imide group derived from the Chemical Formula 3.

6 . The poly(imide-amide) copolymer according to claim 1 , wherein a content of the amide structural unit derived from the amide structural unit-containing oligomer is equal to or greater than about 60 mole percent to about 70 mole percent based on the total mole number of the amide structural unit derived from the oligomer and the imide group derived from the Chemical Formula 3.

7 . The poly(imide-amide) copolymer according to claim 1 , wherein the dianhydride represented by Chemical Formula 3 is a combination of the dianhydride represented by Chemical Formula 4 and the dianhydride represented by Chemical Formula 5, in a mole ratio of about 40:60 to about 60:40.

8 . A poly(imide-amide) copolymer comprising a structural unit represented by Chemical Formula 6 and a structural unit represented by Chemical Formula 7, wherein the poly(imide-amide) copolymer comprises a structural unit comprising two or more of the sequentially linked structural units represented by Chemical Formula 6:

wherein, in Chemical Formula 6,

R 5 is a substituted or unsubstituted phenylene group,

R 6 and R 7 are the same or different and are each independently an electron withdrawing group selected from —CF 3 , —CCl 3 , —CBr 3 , —Cl 3 , —NO 2 , —CN, —C(═O)CH 3 , and —CO 2 C 2 H 5 ,

R 8 and R 9 are the same or different and are each independently a halogen, a hydroxyl group, a substituted or unsubstituted C1 to C10 aliphatic group, a substituted or unsubstituted C6 to C20 aromatic group, an alkoxy group of formula —OR 204 , wherein R 204 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 205 R 206 R 207 , wherein R 205 , R 206 , and R 207 are the same or different and are each independently a hydrogen or a C1 to C10 aliphatic organic group, and

n3 is an integer from 1 to 4, n5 is an integer from 0 to 3, provided that n3+n5 is an integer ranging from 1 to 4,

n4 is an integer from 1 to 4, n6 is an integer from 0 to 3, provided that n4+n6 is an integer ranging from 1 to 4;

wherein, in Chemical Formula 7,

R 10 is single bond, a substituted or unsubstituted C1 to C30 aliphatic organic group, a substituted or unsubstituted C3 to C30 alicyclic organic group, a substituted or unsubstituted C6 to C30 aromatic organic group, or a substituted or unsubstituted C2 to C30 heterocyclic group,

R 11 is a substituted or unsubstituted biphenylene group,

R 12 and R 13 are the same or different, and are each independently a halogen, a hydroxy group, a substituted or unsubstituted C1 to C10 aliphatic organic group, a C6 to C20 aromatic organic group, an alkoxy group of formula —OR 208 , wherein R 208 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 209 R 210 R 211 , wherein R 209 , R 210 , and R 211 are the same or different, and are each independently hydrogen or a C1 to C10 aliphatic organic group, and

n7 and n8 are each independently integers ranging from 0 to 3.

9 . The poly(imide-amide) copolymer according to claim 8 , wherein a content of the structural unit represented by Chemical Formula 6 is equal to or greater than about 20 mole percent to about 70 mole percent based on the total mole number of the structural unit represented by Chemical Formula 6 and the structural unit represented by Chemical Formula 7.

10 . The poly(imide-amide) copolymer according to claim 8 , wherein a content of the structural unit represented by Chemical Formula 6 is equal to or greater than about 50 mole percent to about 70 mole percent based on the total mole number of the structural unit represented by Chemical Formula 6 and the structural unit represented by Chemical Formula 7.

11 . The poly(imide-amide) copolymer according to claim 8 , wherein a content of the structural unit represented by Chemical Formula 6 is equal to or greater than about 60 mole percent to about 70 mole percent based on the total mole number of the structural unit represented by Chemical Formula 6 and the structural unit represented by Chemical Formula 7.

12 . The poly(imide-amide) copolymer according to claim 8 , wherein the structural unit represented by Chemical Formula 7 is at least one of a structural unit represented by Chemical Formula 8 and a structural unit represented by Chemical Formula 9:

In Chemical Formulae 8 and 9,

R 11 to R 13 and n7 and n8 are the same as defined in Chemical Formula 7.

13 . The poly(imide-amide) copolymer according to claim 8 , wherein the poly(imide-amide) copolymer comprises a structural unit comprising the structural unit represented by Chemical Formula 7, which comprises a terminal comprising a structural unit comprising two or more of the sequentially linked structural units represented by Chemical Formula 6.

14 . The poly(imide-amide) copolymer according to claim 8 , wherein the poly(imide-amide) copolymer comprises a structural unit comprising the structural unit represented by Chemical Formula 7, which comprises two termini, each of which comprises a structural unit comprising two or more of the sequentially linked structural units represented by Chemical Formula 6.

15 . The poly(imide-amide) copolymer according to claim 8 , wherein the structural unit represented by Chemical Formula 6 is a structural unit represented by Chemical Formula 10, a structural unit represented by Chemical Formula 11, or a combination thereof:

16 . The poly(imide-amide) copolymer according to claim 12 , wherein the structural unit represented by Chemical Formula 8 is a structural unit represented by Chemical Formula 12, and the structural unit represented by Chemical Formula 9 is a structural unit represented by Chemical Formula 13:

17 . A method for preparing a poly(imide-amide) copolymer comprising reacting a diamine comprising an amide structural unit-containing oligomer represented by Chemical Formula 1 and a dianhydride represented by Chemical Formula 3:

wherein, in Chemical Formula 1,

R 1 and R 2 are the same or different, and are each independently selected from a halogen, a hydroxyl group, a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C6 to C20 aryl group, or a substituted or unsubstituted C1 to C10 alkoxy group,

n1 and n2 are the same or different, and are each independently an integer from 0 to 4, provided that n1+n2 is an integer ranging from 0 to 4,

n0 is equal to or greater than 1, and

Ar 1 and Ar 2 are the same or different and are each independently represented by Chemical Formula 2:

wherein, in Chemical Formula 2,

R 6 and R 7 are the same or different and are each independently an electron withdrawing group selected from —CF 3 , —CCl 3 , —CBr 3 , —Cl 3 , —NO 2 , —CN, —C(═O)CH 3 , and —CO 2 C 2 H 5 ,

R 8 and R 9 are the same or different and are each independently a halogen, a hydroxyl group, a substituted or unsubstituted C1 to C10 aliphatic group, a substituted or unsubstituted C6 to C20 aromatic group, an alkoxy group of formula —OR 204 , wherein R 204 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 205 R 206 R 207 , wherein R 205 , R 206 , and R 207 are the same or different and are each independently a hydrogen or a C1 to C10 aliphatic organic group, and

n3 is an integer from 1 to 4, n5 is an integer from 0 to 3, provided that n3+n5 is an integer ranging from 1 to 4,

n4 is an integer from 1 to 4, n6 is an integer from 0 to 3, provided that n4+n6 is an integer ranging from 1 to 4;

wherein, in Chemical Formula 3,

R 10 is single bond, a substituted or unsubstituted C1 to C30 aliphatic group, a substituted or unsubstituted C3 to C30 alicyclic organic group, a substituted or unsubstituted C6 to C30 aromatic organic group, or a substituted or unsubstituted C2 to C30 heterocyclic group,

R 12 and R 13 are the same or different and are each independently a halogen, a hydroxyl group, a substituted or unsubstituted C1 to C10 aliphatic group, a substituted or unsubstituted C6 to C20 aromatic group, an alkoxy group of formula —OR 205 , wherein R 205 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 209 R 210 R 211 , wherein R 209 , R 210 , and R 211 are the same or different and are each independently a hydrogen or a C1 to C10 aliphatic organic group, and

n7 and n8 are the same or different and are each independently an integer ranging from 0 to 3.

18 . The method according to claim 17 , wherein the diamine further comprises a diamine compound represented by Chemical Formula A:

H 2 N—Ar 3 —NH 2   Chemical Formula A

wherein in Chemical Formula A,

Ar 3 is represented by the above Chemical Formula 2;

wherein, in Chemical Formula 2,

R 6 and R 7 are the same or different and are each independently an electron withdrawing group selected from —CF 3 , —CCl 3 , —CBr 3 , —Cl 3 , —NO 2 , —CN, —C(═O)CH 3 , and —CO 2 C 2 H 5 ,

R 8 and R 9 are the same or different and are each independently a halogen, a hydroxyl group, a substituted or unsubstituted C1 to C10 aliphatic group, a substituted or unsubstituted C6 to C20 aromatic group, an alkoxy group of formula —OR 204 , wherein R 204 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 205 R 206 R 207 , wherein R 205 , R 206 , and R 207 are the same or different and are each independently a hydrogen or a C1 to C10 aliphatic organic group, and

n3 is an integer from 1 to 4, n5 is an integer from 0 to 3, provided that n3+n5 is an integer ranging from 1 to 4,

n4 is an integer from 1 to 4, n6 is an integer from 0 to 3, provided that n4+n6 is an integer ranging from 1 to 4.

19 . The method according to claim 17 , wherein the dianhydride represented by Chemical Formula 3 comprises a dianhydride represented by Chemical Formula 4, Chemical Formula 5, or a combination thereof:

wherein, in Chemical Formulae 4 and 5,

R 12 and R 13 are the same or different, and are each independently a halogen, a hydroxy group, a substituted or unsubstituted C1 to C10 aliphatic organic group, a C6 to C20 aromatic organic group, an alkoxy group of formula —OR 208 , wherein R 208 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 209 R 210 R 211 , wherein R 209 , R 210 , and R 211 are the same or different, and are each independently hydrogen or a C1 to C10 aliphatic organic group, and

n7 and n8 are each independently integers ranging from 0 to 3.

20 . The method according to claim 19 , wherein the amide structural unit-containing oligomer represented by Chemical Formula 1 has a number average molecular weight of about 900 Daltons to about 2,500 Daltons.

21 . An article comprising the poly(imide-amide) copolymer according to claim 1 .

22 . The article according to claim 21 , which has a yellowness index of equal to or less than about 3, measured for a film having a thickness of about 50 micrometers to about 100 micrometers, according to an ASTM D 1925 method.

23 . The article according to claim 21 , which has a tensile modulus of greater than or equal to about 4 gigapascals, measured for a film having a thickness of about 50 micrometers to about 100 micrometers, according to an ASTM D882 method.

24 . A display device comprising the article according to claim 21 .

25 . The display device according to claim 24 , wherein the display device is a flexible display device.