Patent ID: 11945908
Assignee: IDEMITSU KOSAN CO., LTD.
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC C | IPC C

Claim 0:
1. A polycarbonate-polyorganosiloxane copolymer (A), comprising:
a polycarbonate block (A-1) formed of a repeating unit represented by the following general formula (I); and
a polyorganosiloxane block (A-2) containing a repeating unit represented by the following general formula (II), wherein the polycarbonate-polyorganosiloxane copolymer satisfies the following conditions (1) to (7):
(1) a content of the polyorganosiloxane block (A-2) in the polycarbonate-polyorganosiloxane copolymer (A) is more than 50 mass % and no more than 60 mass %;
(2) the polyorganosiloxane block (A-2) has a number of repetitions of from 10 or more to 40 or less;
(3) the polycarbonate-polyorganosiloxane copolymer has a viscosity-average molecular weight of from 10,000 or more to 23,000 or less;
(4) the polycarbonate-polyorganosiloxane copolymer comprises 100 mass % of a bisphenol A (BPA) block based on 100 mass % of the polycarbonate block (A-1), the BPA block being a polycarbonate block that in the following general formula (I), “a” and “b” each represent 0, and X represents an isopropylidene group;
(5) the polycarbonate-polyorganosiloxane copolymer has a total light transmittance of 85% or more measured in conformity with JIS K 7361-1:1997 when molded into a thickness of 2 mm;
(6) the polycarbonate-polyorganosiloxane copolymer has a durometer hardness of from 25 or more to 60 or less measured with a type D durometer in conformity with JIS K 6253-3:2012; and
(7) a content of a unit represented by the following general formula (III) in the polyorganosiloxane block (A-2) is 0.1 mol % or less:, wherein R1 and R2 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, an arylene group having 6 to 12 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—, —SO2-, —O—, or —CO—, R3 and R4 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:, wherein R33 and R34 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, R31 represents 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, an arylene group having 6 to 12 carbon atoms, a fluorenediyl group, an arylalkylene group having 7 to 15 carbon atoms, or an arylalkylidene group having 7 to 15 carbon atoms, R35 represents 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 “t” represents an average chain length of a polyorganosiloxane.