Polycarbonate resin composition and molded article thereof

1. A polycarbonate-based resin composition, comprising:

a polycarbonate-polyorganosiloxane copolymer (A) containing a polycarbonate block (A-1) comprising a repeating unit represented by the following general formula (I) and a polyorganosiloxane block (A-2) comprising a repeating unit represented by the following general formula (II); and

an aromatic polycarbonate-based resin (B) except the polycarbonate-polyorganosiloxane copolymer (A),

wherein the polycarbonate-based resin composition has a structure in which a domain (d-1) containing the polyorganosiloxane block (A-2) is present in a matrix containing the aromatic polycarbonate-based resin (B) as a main component, and a domain (d-2) containing at least one selected from a block derived from the aromatic polycarbonate-based resin (B) and the polycarbonate block (A-1) is present inside the domain (d-1):

wherein R 1 and R 2 each independently represent a halogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, X represents a single bond, an alkylene group having 1 to 8 carbon atoms, an alkylidene group having 2 to 8 carbon atoms, a cycloalkylene group having 5 to 15 carbon atoms, a cycloalkylidene group having 5 to 15 carbon atoms, a fluorenediyl group, an arylalkylene group having 7 to 15 carbon atoms, an arylalkylidene group having 7 to 15 carbon atoms, —S—, —SO—, —SO 2 —, —O—, or —CO—, R 3 and R 4 each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and a and b each independently represent an integer of from 0 to 4.

2. The polycarbonate-based resin composition according to claim 1 , wherein a mass ratio “(A)/(B)” of the polycarbonate-polyorganosiloxane copolymer (A) to the aromatic polycarbonate-based resin (B) is from 0.1/99.9 to 99.9/0.1.

3. The polycarbonate-based resin composition according to claim 1 , wherein the aromatic polycarbonate-based resin (B) contains a polycarbonate block comprising, in a main chain thereof, a repeating unit represented by the following general formula (III):

wherein R 9 and R 10 each independently represent a halogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, X′ represents a single bond, an alkylene group having 1 to 8 carbon atoms, an alkylidene group having 2 to 8 carbon atoms, a cycloalkylene group having 5 to 15 carbon atoms, a cycloalkylidene group having 5 to 15 carbon atoms, —S—, —SO—, —SO 2 —, —O—, or —CO—, and d and e each independently represent an integer of from 0 to 4.

4. The polycarbonate-based resin composition according to claim 1 , wherein the domain (d-1) is mainly formed of the polyorganosiloxane block (A-2).

5. The polycarbonate-based resin composition according to claim 1 , wherein the domain (d-2) is mainly formed of at least one selected from the block derived from the aromatic polycarbonate-based resin (B) and the polycarbonate block (A-1).

6. The polycarbonate-based resin composition according to claim 1 , wherein only the one domain (d-2) is present inside the domain (d-1).

7. The polycarbonate-based resin composition according to claim 1 , wherein the two or more domains (d-2) are present inside the domain (d-1).

8. The polycarbonate-based resin composition according to claim 1 , wherein a ratio of a number of domains (d) in each of which the domain (d-2) is present inside the domain (d-1) to a total number of the domains (d) and domains (d′) each formed only of the domain (d-1) is from 2% to 100%.

9. The polycarbonate-based resin composition according to claim 8 , wherein an average cross-section area of all domains corresponding to a total of the domains (d) and the domains (d′) is 200 nm 2 or more.

10. The polycarbonate-based resin composition according to claim 8 , wherein an average cross-section area of all domains corresponding to a total of the domains (d) and the domains (d′) is 20,000 nm 2 or less.

11. The polycarbonate-based resin composition according to claim 8 , wherein a mean inter-particle distance of all domains corresponding to a total of the domains (d) and the domains (d′) is 500 nm or less.

12. The polycarbonate-based resin composition according to claim 8 , wherein a mean inter-particle distance of all domains corresponding to a total of the domains (d) and the domains (d′) is 50 nm or more.

13. The polycarbonate-based resin composition according to claim 1 , wherein the polyorganosiloxane block (A-2) has an average chain length of from 30 to 500.

14. The polycarbonate-based resin composition according to claim 1 , wherein the polyorganosiloxane block (A-2) has an average chain length of from 55 to 500.

15. The polycarbonate-based resin composition according to claim 1 , wherein a content of the polyorganosiloxane block (A-2) in the polycarbonate-polyorganosiloxane copolymer (A) is from 5 mass % to 70 mass %.

16. The polycarbonate-based resin composition according to claim 1 , wherein a content of the polyorganosiloxane block (A-2) in the polycarbonate-based resin composition is from 0.1 mass % to 10 mass %.

17. The polycarbonate-based resin composition according to claim 1 , wherein the polycarbonate-polyorganosiloxane copolymer (A) has a viscosity-average molecular weight (Mv) of from 9,000 to 50,000.

18. The polycarbonate-based resin composition according to claim 1 , wherein the polycarbonate-based resin composition has a viscosity-average molecular weight (Mv) of from 9,000 to 50,000.

19. A molded article, which is obtained by molding the polycarbonate-based resin composition of claim 1 .

20. The molded article according to claim 19 , wherein the molded article comprises a casing for electrical and electronic equipment.

21. The molded article according to claim 19 , wherein the molded article comprises a part for an automobile and a building material.