POLY(AMIDE-IMIDE) COPOLYMER, COMPOSITION FOR PREPARING POLY(AMIDE-IMIDE) COPOLYMER, ARTICLE INCLUDING POLY(AMIDE-IMIDE) COPOLYMER, AND DISPLAY DEVICE INCLUDING THE ARTICLE

1 . A poly(amide-imide) copolymer that is a reaction product of a diamine represented by Chemical Formula 1, a diamine represented by Chemical Formula 2, a dicarbonyl compound represented by Chemical Formula 3, and a tetracarboxylic acid dianhydride represented by Chemical Formula 4:

NH 2 -L 1 -Si(R a )(R b )—O—Si(R c )(R d )-L 2 -NH 2   Chemical Formula 1

wherein in Chemical Formula 1,

L 1 and L 2 are each independently a single bond, a C1 to C30 alkylene group, a C2 to C30 alkenylene group, a C3 to C30 cycloalkylene group, or a combination thereof,

R a to R d are each independently a C1 to C30 alkyl group, a C2 to C30 alkenyl group, a C2 to C30 alkynyl group, a C1 to C30 alkoxy group, a C3 to C30 cycloalkyl group, or a combination thereof;

NH 2 —R 2 —NH 2   Chemical Formula 2

wherein in Chemical Formula 2,

R 2 comprises a substituted or unsubstituted C6 to C30 aromatic organic group, wherein the substituted or unsubstituted C6 to C30 aromatic organic group includes one substituted or unsubstituted aromatic ring, two or more substituted or unsubstituted aromatic rings fused together to provide a condensed ring system, or two or more substituted or unsubstituted aromatic moieties independently selected from the foregoing linked through a single bond or through a functional group selected from a fluorenylene group, —O—, —S—, —C(═O)—, —CH(OH)—, —S(═O) 2 —, —Si(CH 3 ) 2 —, —(CH 2 ) p — wherein 1≤p≤10, —(CF 2 ) q — wherein 1≤q≤10, —C(CH 3 ) 2 —, —C(CF 3 ) 2 —, —C(═O)NH—, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C6 to C15 arylene group, and a combination thereof;

wherein, in Chemical Formula 3,

R 3 is a substituted or unsubstituted phenylene or biphenylene group, and

each X is an identical or a different halogen atom;

wherein, in Chemical Formula 4,

R 10 is a single bond, —O—, —S—, —C(═O)—, —CH(OH)—, —C(═O)NH—, —S(═O) 2 —, —Si(CH 3 ) 2 —, —(CH 2 ) p — wherein 1≤p≤10, —(CF 2 ) q — wherein 1≤q≤10, —C(C n H 2n+1 ) 2 —, —C(C n F 2n+1 ) 2 —, —(CH 2 ) p C(C n H 2n+1 ) 2 (CH 2 ) q —, or —(CH 2 ) p C(C n F 2n+1 ) 2 (CH 2 ) q — wherein 1≤n≤10, 1≤p≤10, and 1≤q≤10,

R 12 and R 13 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 201 , wherein R 201 is a C1 to C10 aliphatic organic group, or a silyl group of formula —SiR 210 R 211 R 212 , wherein R 210 , R 211 , and R 212 are each independently hydrogen or a C1 to C10 aliphatic organic group, and

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

2 . The poly(amide-imide) copolymer according to claim 1 , wherein in Chemical Formula 1, L 1 and L 2 is independently a C1 to C30 alkylene group, and R a to R d are each independently a C1 to C30 alkyl group.

3 . The poly(amide-imide) copolymer according to claim 1 , wherein in Chemical Formula 1, both L 1 and L 2 are propylene groups, and each of R a to R d are methyl groups.

4 . The poly(amide-imide) copolymer according to claim 1 , wherein the diamine represented by Chemical Formula 2 comprises at least one selected from the diamines represented by the following chemical formulae:

wherein in the above chemical formulae,

R 32 to R 34 , R 39 to R 41 , and R 45 to R 48 are each independently a halogen, a nitro group, a substituted or unsubstituted C1 to C15 alkyl group, a substituted or unsubstituted C1 to C15 alkoxy group, a substituted or unsubstituted C1 to C15 fluoroalkyl group, a substituted or unsubstituted C3 to C15 cycloalkyl group, a substituted or unsubstituted C3 to C15 heterocycloalkyl group, a substituted or unsubstituted C3 to C15 oxycycloalkyl group, a substituted or unsubstituted C6 to C15 aryl group, a substituted or unsubstituted C6 to C15 oxyaryl group, or a substituted or unsubstituted C2 to C15 heteroaryl group,

X 2 to X 6 , and X 8 to X 10 are each independently a single bond, fluorenylene group, a substituted or unsubstituted C1 to C10 alkylene group, a substituted or unsubstituted C1 to C10 cycloalkylene group, a substituted or unsubstituted C6 to C15 arylene group, —O—, —S—, —C(═O)—, —CH(OH)—, —S(═O) 2 —, —Si(CH 3 ) 2 —, —(CH 2 ) p — wherein 1≤p≤10, —(CF 2 ) q — wherein 1≤q≤10, —C(CH 3 ) 2 —, —C(CF 3 ) 2 —, —C(═O)NH—, or a combination thereof, and

n35 to n37, n40 to n42, and n46 to n49 are each independently an integer ranging from 0 to 4.

5 . The poly(amide-imide) copolymer according to claim 1 , wherein the diamine represented by Chemical Formula 2 comprises at least one selected from the diamines represented by the following chemical formulae:

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

7 . The poly(amide-imide) copolymer according to claim 1 , wherein in Chemical Formula 3, R 3 is a phenylene group, and each X is independently Cl or Br.

8 . The poly(amide-imide) copolymer according to claim 1 , wherein the tetracarboxylic acid dianhydride represented by Chemical Formula 4 comprises at least one selected from 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (BPDA), 3,3′,4,4′-diphenylsulfone tetracarboxylic dianhydride (DSDA), 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), and 4,4′-oxydiphthalic anhydride (ODPA).

9 . The poly(amide-imide) copolymer according to claim 1 , wherein the tetracarboxylic acid dianhydride represented by Chemical Formula 4 comprises a combination of the compound represented by Chemical Formula 4 wherein R 10 is a single bond, and both n7 and n8 are 0, and the compound represented by Chemical Formula 4 wherein R 10 is —C(C n F 2n+1 ) 2 — wherein 1≤n≤10, and both n7 and n8 are 0.

10 . The poly(amide-imide) copolymer according to claim 1 , wherein an amount of the diamine represented by Chemical Formula 1 is less than 50 mole percent based on the total amount of the diamine represented by Chemical Formula 1 and the diamine represented by Chemical Formula 2.

11 . The poly(amide-imide) copolymer according to claim 1 , wherein a mole ratio of the dicarbonyl compound represented by Chemical Formula 3 and the tetracarboxylic acid dianhydride represented by Chemical Formula 4 is 30 to 70:70 to 30.

12 . The poly(amide-imide) copolymer according to claim 1 , wherein the total amount of the diamine represented by Chemical Formula 2 and the dicarbonyl compound represented by Chemical Formula 3 are equal to or greater than 50 mole percent based on the total amount of the compounds represented by Chemical Formulae 1 to 4.

13 . A composition for preparing a poly(amide-imide) copolymer comprising a diamine represented by Chemical Formula 5, a diamine represented by Chemical Formula 1, and a tetracarboxylic acid dianhydride represented by Chemical Formula 4:

wherein, in Chemical Formula 5,

R 4 and R 5 are each independently a halogen, a hydroxy group, a substituted or unsubstituted C1 to C10 alkyl group, or a substituted or unsubstituted C1 to C10 alkoxy group,

n0 is an integer greater than or equal to 0,

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

Ar 1 and Ar 2 are each independently represented by Chemical Formula 6:

wherein, in Chemical Formula 6,

R 6 and R 7 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 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 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 each independently hydrogen or a C1 to C10 aliphatic organic group,

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

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

NH 2 -L 1 -Si(R a )(R b )—O—Si(R c )(R d )-L 2 -NH 2   Chemical Formula 1

wherein in Chemical Formula 1,

L 1 and L 2 are each independently a single bond, a C1 to C30 alkylene group, a C2 to C30 alkenylene group, a C3 to C30 cycloalkylene group, or a combination thereof,

R a to R d are each independently a C1 to C30 alkyl group, a C2 to C30 alkenyl group, a C2 to C30 alkynyl group, a C1 to C30 alkoxy group, a C3 to C30 cycloalkyl group, or a combination thereof;

wherein, in Chemical Formula 4,

R 10 is a single bond, —O—, —S—, —C(═O)—, —CH(OH)—, —C(═O)NH—, —S(═O) 2 —, —Si(CH 3 ) 2 —, —(CH 2 ) p — wherein 1≤p≤10, —(CF 2 ) q — wherein 1≤q≤10, —C(C n H 2n+1 ) 2 —, —C(C n F 2n+1 ) 2 —, —(CH 2 ) p C(C n H 2n+1 ) 2 (CH 2 ) q —, or —(CH 2 ) p C(C n F 2n+1 ) 2 (CH 2 ) q — wherein 1≤n≤10, 1≤p≤10, and 1≤q≤10,

R 12 and R 13 are each independently a halogen, a hydroxy group, a substituted or unsubstituted C1 to C10 aliphatic organic group, a substituted or unsubstituted C6 to C20 aromatic organic group, an alkoxy group of formula —OR 201 , wherein R 201 is a C1 to 010 aliphatic organic group, or a silyl group of formula —SiR 210 R 211 R 212 , wherein R 210 , R 211 , and R 212 are each independently hydrogen or a C1 to C10 aliphatic organic group, and

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

14 . The composition for preparing a poly(amide-imide) copolymer according to claim 13 , wherein the composition further comprises a diamine represented by Chemical Formula 2:

NH 2 —R 2 —NH 2   Chemical Formula 2

wherein in Chemical Formula 2,

R 2 comprises a substituted or unsubstituted C6 to C30 aromatic organic group, wherein the substituted or unsubstituted C6 to C30 aromatic organic group includes one substituted or unsubstituted aromatic ring, two or more substituted or unsubstituted aromatic rings fused together to provide a condensed ring system, or two or more substituted or unsubstituted aromatic moieties independently selected from the foregoing linked through a single bond or through a functional group selected from a fluorenylene group, —O—, —S—, —C(═O)—, —CH(OH)—, —S(═O) 2 —, —Si(CH 3 ) 2 —, —(CH 2 ) p — wherein 1≤p≤10, —(CF 2 ) q — wherein 1≤q≤10, —C(CH 3 ) 2 —, —C(CF 3 ) 2 —, —C(═O)NH—, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C6 to C15 arylene group, and a combination thereof.

15 . The composition for preparing a poly(amide-imide) copolymer according to claim 13 , wherein in Chemical Formula 1, L 1 and L 2 are each independently a C1 to C30 alkylene group, and R a to R d are each independently a C1 to C30 alkyl group.

16 . The composition for preparing a poly(amide-imide) copolymer according to claim 13 , wherein the tetracarboxylic acid dianhydride represented by Chemical Formula 4 comprises a combination of the compound represented by Chemical Formula 4 wherein R 10 is single bond, and both n7 and n8 are 0, and the compound represented by Chemical Formula 4 wherein R 10 is —C(C n F 2n+1 ) 2 — wherein 1≤n≤10, and both n7 and n8 are 0.

17 . The composition for preparing a poly(amide-imide) copolymer according to claim 13 , wherein both n1 and n2 of Chemical Formula 5 are zero, and both R 6 and R 7 are —CF 3 , both n3 and n4 are 1, and both n5 and n6 are zero in Chemical Formula 6.

18 . An article comprising a poly(amide-imide) copolymer according to claim 1 .

19 . The article according to claim 18 , wherein the article comprises a film, wherein the film has a toughness of greater than or equal to 1,000 Joules×reverse cubic meters×10 4 (Joul·m −3 ·10 4 ), and a refractive index of less than or equal to 1.68, when the film has a thickness of about 35 micrometers to about 100 micrometers.

20 . A display device comprising the article according to claim 18 .