Self-healing conjugated polymer, composition for forming self-healing photoactive layer including the conjugated polymer and organic solar cell including photoactive layer formed using the composition

1. A self-healing conjugated polymer represented by Formula I:

wherein R 1 , R 2 , R 4 , and R 5 are identical to or different from each other and are each independently a group represented by Structure 1:

(wherein R 7 and R 8 are identical to or different from each other and are each independently selected from hydrogen atoms, halogen atoms, cyano groups, nitro groups, hydroxyl groups, amide groups, ester groups, ketone groups, thioester groups, silyl groups, and substituted or unsubstituted C 1 -C 30 alkyl groups and the asterisk (*) represents a bonding site to the backbone), R 3 is selected from the group consisting of substituted or unsubstituted C 1 -C 6 alkyl groups, substituted or unsubstituted C 7 -C 30 alkyl groups, substituted or unsubstituted C 5 -C 35 alkylthionyl groups, and substituted or unsubstituted C 3 -C 30 cycloalkyl groups, R 6 is a C 1 -C 10 alkylene group, x is real number satisfying 0.1≤x≤0.9, and n is an integer from 5 to 100,000.

2. The self-healing conjugated polymer according to claim 1 , wherein R 1 , R 2 , R 4 , and R 5 are identical to each other, R 7 represents a 2-butyl-2-ethyl-1-ethyl group, R 8 represents a fluoro group, R 3 represents an ethyl group, and R 6 represents a 1,5-penthylene group.

3. The self-healing conjugated polymer according to claim 1 , wherein the conjugated polymer has a number average molecular weight (M n ) of 1 to 100 kg/mol and a polydispersity (PD) (M w /M n ) of 1 to 3.

4. The self-healing conjugated polymer according to claim 1 , wherein x is real number satisfying 0.8≤x≤0.9.

5. A composition for forming a self-healing photoactive layer, comprising a solvent and a conjugated polymer represented by Formula I:

wherein R 1 , R 2 , R 4 , and R 5 are identical to or different from each other and are each independently a group represented by Structure 1:

(wherein R 7 and R 8 are identical to or different from each other and are each independently selected from hydrogen atoms, halogen atoms, cyano groups, nitro groups, hydroxyl groups, amide groups, ester groups, ketone groups, thioester groups, silyl groups, and substituted or unsubstituted C 1 -C 30 alkyl groups and the asterisk (*) represents a bonding site to the backbone), R 3 is selected from the group consisting of substituted or unsubstituted C 1 -C 6 alkyl groups, substituted or unsubstituted C 7 -C 30 alkyl groups, substituted or unsubstituted C 5 -C 35 alkylthionyl groups, and substituted or unsubstituted C 3 -C 30 cycloalkyl groups, R 6 is a C 1 -C 10 alkylene group, x is real number satisfying 0.1≤x≤0.9, and n is an integer from 5 to 100,000.

6. The composition according to claim 5 , wherein R 1 , R 2 , R 4 , and R 5 are identical to each other, R 7 represents a 2-butyl-2-ethyl-1-ethyl group, R 8 represents a fluoro group, R 3 represents an ethyl group, and R 6 represents a 1,5-penthylene group and wherein the solvent is selected from the group consisting of dimethylformamide, dichloromethane, chloroform, hexane, cyclohexane, toluene, xylene, chlorobenzene, dichlorobenzene, ethylene acetate, tetrahydrofuran, N-methylpyrrolidinone, and mixtures thereof.

7. The composition according to claim 5 , further comprising n-type molecules.

8. The composition according to claim 7 , wherein the n-type molecules are selected from the group consisting of 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d]-s-indaceno[1,2-b:5,6-b′]dithiophene (ITIC), 3,9-bis(2-methylene-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile)-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene (IT-4F), (5Z,5′Z)-5,5′-(((4,4,9,9-tetraoctyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b′]dithiophene-2,7-diyl)bis(benzo[c][1,2,5]thiadiazole-7,4-diyl))bis(methanylylidene))bis(3-ethyl-2-thioxothiazolidin-4-one) (O-IDTBR), 2,2′-((2Z,2′Z)-(((4,4,9,9-tetrakis(4-hexylphenyl)-4,9-dihydro-sindaceno[1,2-b:5,6-b′]dithiophene-2,7-diyl)bis(4-((2-ethylhexyl)oxy)thiophene-5,2-diyl))bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile (IEICO-4F), 5,5′-(9,9′-spirobi[fluorene]-2,7-diyl)bis(2,9-dimethylanthra[2,1,9-def:6,5,10-de′f]diisoquinoline-1,3,8,10(2H,9H)-tetraone) (SF-PDI 2 ), (2,20-((2Z,20Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2″,3′:4′,5′]thieno[2′,3′:4,5]pyrrolo[3,2-g]thieno[2′,3′:4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile) (Y6), (6,6)-phenyl-C61-butyric acid methyl ester (C 60 -PCBM), (6,6)-phenyl-C71-butyric acid methyl ester (C 70 -PCBM), bis(1-[3-(methoxycarbonyl)propyl]-1-phenyl) (Bis-C 60 -PCBM), 3′-phenyl-3′H-cyclopropa(8,25)(5,6)fullerene-C70-bis-D5h(6)-3′-butyric acid methyl ester (Bis-C 70 -PCBM), indene-C60-bisadduct (ICBA), monoindenyl C60 (ICMA) molecules, and combinations thereof.

9. A photoactive layer for an organic solar cell comprising the composition according to claim 5 .

10. An organic solar cell employing the photoactive layer according to claim 9 .

11. The organic solar cell according to claim 10 , wherein the organic solar cell comprises a substrate, a first electrode disposed on the substrate, a buffer layer disposed on the first electrode, the photoactive layer disposed on a charge transport layer, and a second electrode disposed on the photoactive layer.