Binder and preparation method thereof, secondary battery, battery module, battery pack and electrical device

1. A binder, comprising:

a copolymer including a building block (I) and a building block (II), the building block (I) being formed by copolymerizing a building block (i) and a building block (ii);

wherein:

 in the building block (i), R1-R6 each independently represent a hydrogen atom, a halogen atom, an unsubstituted or substituted alkyl with 1-6 carbon atoms, an unsubstituted or substituted alkoxy with 1-6 carbon atoms, an unsubstituted or substituted alkenyl with 1-6 carbon atoms, an unsubstituted or substituted aryl with 6-20 carbon atoms, hydroxyl, or amino, and

substituents in the substituted alkyl with 1-6 carbon atoms, the substituted alkoxy with 1-6 carbon atoms, the substituted alkenyl with 1-6 carbon atoms, or the aryl with 6-20 carbon atoms in R1-R6 are selected from at least one of hydroxyl, amino, amido, cyano, carboxyl, or a halogen atom,

 in the building block (ii), R7-R9 each independently represent a hydrogen atom, an unsubstituted or substituted alkyl with 1-6 carbon atoms, an unsubstituted or substituted alkoxy with 1-6 carbon atoms, an unsubstituted or substituted alkylamino with 1-6 carbon atoms, an unsubstituted or substituted alkenyl with 1-6 carbon atoms, an unsubstituted or substituted aryl with 6-20 carbon atoms, hydroxyl, or amino, and

 substituents in the substituted alkyl with 1-6 carbon atoms, the substituted alkoxy with 1-6 carbon atoms, the substituted alkylamino with 1-6 carbon atoms, the substituted alkenyl with 1-6 carbon atoms, or the substituted aryl with 6-20 carbon atoms in R7-R9 are selected from at least one of hydroxyl, carboxyl, amino, amido, or a halogen atom, and

 in the building block (II), R10 represents a hydrogen atom, a halogen atom, an unsubstituted or substituted alkyl with 1-6 carbon atoms, an unsubstituted or substituted alkoxy with 1-6 carbon atoms, an unsubstituted or substituted alkenyl with 1-6 carbon atoms, an unsubstituted or substituted aryl with 6-20 carbon atoms, hydroxyl, or amino,

 substituents in the substituted alkyl with 1-6 carbon atoms, the substituted alkoxy with 1-6 carbon atoms, the substituted alkenyl with 1-6 carbon atoms, or the aryl with 6-20 carbon atoms in R10 are selected from at least one of hydroxyl, carboxyl, amino, amido, cyano, or a halogen atom, and

 R11 represents a bridging oxo group or a bridging imino group, and a plurality of M each independently represent one of Li, Na, K, Rb and Cs.

2. The binder according to claim 1 , wherein:

a ratio of a sum of a monomeric average molar number, a, of the building block (i) and a monomeric average molar number, b, of the building block (ii) to a monomeric average molar number, c, of the building block (II) is (a+b)/c=0.1-10.

3. The binder according to claim 2 , wherein:

the ratio of the sum of the monomeric average molar number, a, of the building block (i) and the monomeric average molar number, b, of the building block (ii) to the monomeric average molar number, c, of the building block (II) is (a+b)/c=0.5-4.

4. The binder according to claim 1 , wherein:

a ratio of a monomeric average molar number, a, of the building block (i) to a monomeric average molar number, b, of the building block (ii) is a/b=1-50.

5. The binder according to claim 4 , wherein:

the ratio of the monomeric average molar number, a, of the building block (i) to the monomeric average molar number, b, of the building block (ii) is a/b=1-13.

6. The binder according to claim 1 , wherein:

in the building block (i), R1-R6 each independently represent a hydrogen atom or an unsubstituted or substituted linear, branched, or cyclic alkyl with 1-6 carbon atoms.

7. The binder according to claim 6 , wherein:

in the building block (i), R1-R6 each independently represent a hydrogen atom or a linear or branched alkyl with 1-3 carbon atoms.

8. The binder according to claim 7 , wherein:

in the building block (i), R1-R6 each independently represent a hydrogen atom or a linear alkyl with 1-3 carbon atoms.

9. The binder according to claim 1 , wherein:

in the building block (ii), R7-R9 each independently represent a hydrogen atom or an unsubstituted or substituted linear, branched, or cyclic alkyl with 1-6 carbon atoms.

10. The binder according to claim 9 , wherein:

in the building block (ii), R7-R9 each independently represent a hydrogen atom or a linear or branched alkyl with 1-3 carbon atoms.

11. The binder according to claim 10 , wherein:

in the building block (ii), R7-R9 each independently represent a hydrogen atom or a linear alkyl with 1-3 carbon atoms.

12. The binder according to claim 1 , wherein:

in the building block (II), R10 represents a hydrogen atom, a halogen atom, or an unsubstituted or substituted linear, branched, or cyclic alkyl with 1-6 carbon atoms.

13. The binder according to claim 12 , wherein:

in the building block (II), R10 represents a hydrogen atom, a halogen atom, or a linear or branched alkyl with 1-3 carbon atoms.

14. The binder according to claim 13 , wherein:

in the building block (II), R10 represents a hydrogen atom, a halogen atom, or a linear alkyl with 1-3 carbon atoms.

15. The binder according to claim 1 , wherein:

in the building block (II), R11 represents a bridging oxo group.

16. The binder according to claim 1 , wherein:

in the building block (II), the plurality of M each independently represent one of Li, Na, and K.

17. The binder according to claim 1 , wherein:

a number average molecular weight of the copolymer is 50,000 to 2,000,000.

18. The binder according to claim 17 , wherein:

the number average molecular weight of the copolymer is 300,000 to 1,000,000.

19. A preparation method of the binder according to claim 1 , comprising:

synthesizing the building block (II);

polymerizing the building block (i) with the building block (ii) to form the building block (I); and

adding the building block (II) to the building block (I) to form the copolymer contained in the binder.

20. A secondary battery comprising an electrode sheet, the electrode sheet including a binder including:

a copolymer including a building block (I) and a building block (II), the building block (I) being formed by copolymerizing a building block (i) and a building block (ii);

wherein:

 in the building block (i), R1-R6 each independently represent a hydrogen atom, a halogen atom, an unsubstituted or substituted alkyl with 1-6 carbon atoms, an unsubstituted or substituted alkoxy with 1-6 carbon atoms, an unsubstituted or substituted alkenyl with 1-6 carbon atoms, an unsubstituted or substituted aryl with 6-20 carbon atoms, hydroxyl, or amino, and

 substituents in the substituted alkyl with 1-6 carbon atoms, the substituted alkoxy with 1-6 carbon atoms, the substituted alkenyl with 1-6 carbon atoms, or the aryl with 6-20 carbon atoms in R1-R6 are selected from at least one of hydroxyl, amino, amido, cyano, carboxyl, or a halogen atom,

 in the building block (ii), R7-R9 each independently represent a hydrogen atom, an unsubstituted or substituted alkyl with 1-6 carbon atoms, an unsubstituted or substituted alkoxy with 1-6 carbon atoms, an unsubstituted or substituted alkylamino with 1-6 carbon atoms, an unsubstituted or substituted alkenyl with 1-6 carbon atoms, an unsubstituted or substituted aryl with 6-20 carbon atoms, hydroxyl, or amino, and

 substituents in the substituted alkyl with 1-6 carbon atoms, the substituted alkoxy with 1-6 carbon atoms, the substituted alkylamino with 1-6 carbon atoms, the substituted alkenyl with 1-6 carbon atoms, or the substituted aryl with 6-20 carbon atoms in R7-R9 are selected from at least one of hydroxyl, carboxyl, amino, amido, or a halogen atom, and

 in the building block (II), R10 represents a hydrogen atom, a halogen atom, an unsubstituted or substituted alkyl with 1-6 carbon atoms, an unsubstituted or substituted alkoxy with 1-6 carbon atoms, an unsubstituted or substituted alkenyl with 1-6 carbon atoms, an unsubstituted or substituted aryl with 6-20 carbon atoms, hydroxyl, or amino,

 substituents in the substituted alkyl with 1-6 carbon atoms, the substituted alkoxy with 1-6 carbon atoms, the substituted alkenyl with 1-6 carbon atoms, or the aryl with 6-20 carbon atoms in R10 are selected from at least one of hydroxyl, carboxyl, amino, amido, cyano, or a halogen atom, and

 R11 represents a bridging oxo group or a bridging imino group, and a plurality of M each independently represent one of Li, Na, K, Rb and Cs.