Process and catalyst composition for producing selectively hydrogenated conjugated diene polymer

A catalyst composition for selectively hydrogenating a conjugated diene polymer comprising a conjugated diene monomer or a combination of a conjugated diene monomer and a vinyl aromatic monomer, the catalyst composition comprising components of:

• (a) a titanium compound of a formula (I),
• wherein:
• R1 and R2 are identical or different and are ones selected from the group consisting of hydrogen, halogen, C1-C8 alkyl, C1-C8 alkoxy, C6-C12 cycloalkyl, phenyl, phenoxy, C7-C10 arylalkoxy, C7-C10 arylalkyl, carboxy, —CH2P(phenyl)2, —CH2Si(C1-C5 alkyl)3 and —P(phenyl)2;
• and A is one selected from the group consisting of cyclopentadienyl, fluorenyl, indenyl and derivatives thereof, wherein A2 can be two of the same A or different A;
• (b) an organometallic compound selected from the group consisting of R3Li, R3R4Mg and R3R4R5Al, wherein said R3 is one selected from the group consisting of hydrogen, C1-C12 alkyl, C1-C12 alkoxy, C6-C12 aryl and C6-C12 alkoxy, and said R4 and R5 are identical or different and are ones selected from the group consisting of hydrogen, halogen, C1-C12 alkyl and C6-C12 aryl;
• and
• (c) an oligomer containing a polyglycol segment, wherein the catalyst component (c) has a weight average molecular weight (Mw) from 400 to 10,000 and a molar ratio of the catalyst component (a) to the catalyst component (b) is from 0.01 to 50.