Propylene copolymer, polypropylene composition and uses thereof, transition metal compound and olefin polymerization catalyst

A transition metal compound represented by the following formula (2a):

• wherein each of R1 and R3 is hydrogen, R2 and R4 are the same or different from each other and selected from the group consisting of a hydrocarbon group and a silicon-containing group, R5, R6, R7, R8, R9, R10, R11, R12 and R13 are the same or different from each other and selected from the group consisting of a hydrogen, a hydrocarbon group and a silicon-containing group, and adjacent substituent groups R5 to R12 are optionally linked to form a ring, R14 is an aryl group, and R13 and R14 are the same or different from each other and optionally linked to form a ring;
• M is a Group 4 transition metal;
• Y is a carbon atom;
• Q is identical or different from each other and selected from the group consisting of halogen, a hydrocarbon group, anion ligand or neutral ligand capable of coordination with a lone pair of electrons;
• and
• j is an integer of 1 to 4.