Patent ID: 9546238
Date: 2017-01-17
CPC Classifications: C08C,C08F

Claim:
1. A method of producing a hydrogenated conjugated diene copolymer comprising: a polymerization step of copolymerizing butadiene monomers and vinyl aromatic monomers using an initiator comprising an organolithium compound; and a hydrogenation step of hydrogenating the conjugated diene copolymer obtained in the polymerization step, wherein in the polymerization step, the organolithium compound, an ether compound (A) having two or more oxygen atoms, and an alkali metal alkoxide (B) are present together in the following molar ratios: ether compound (A)/organolithium compound ((A)/organolithium compound) is 1.7 or more and 2.4 or less; alkali metal alkoxide (B)/organolithium compound ((B)/organolithium compound) is 0.015 or more and 0.150 or less, alkali metal alkoxide (B)/ether compound (A) ((B)/(A)) is 0.006 or more and 0.076 or less, the ether compound (A) is selected from the group consisting of 2,2-diethoxypropane, 1,2-diethoxypropane, ethylene glycol dibutyl ether ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, ethyl ethylene glycol t-butyl ether, ethyl ethylene glycol butyl ether, triethylene glycol dimethyl ether, bis(2-oxolanyl)ethane, 2,2-bis(2-oxolanyl)propane, 1,1-bis(2-oxolanyl)ethane, 2,2-bis(2-oxolanyl)butane, 2,2-bis(5-methyl-2-oxolanyl)propane, and 2,2-bis(3,4,5-trimethyl-2-oxolanyl)propane, the alkali metal alkoxide (B) is sodium, lithium or potassium alkoxide having an alkyl group having 2 to 12 carbon atoms, and the vinyl aromatic monomers comprise styrene, α-methylstyrene, p-methylstyrene, vinylethylbenzene, and/or 2-vinylnaphthalene.