| abstract |
A solid titanium catalyst component (I) of the present invention is characterized in that it contains titanium, magnesium, halogen, and a cyclic ester compound (a) represented by the following formula (1) :n nwherein n is an integer of 5 to 10; nR 2 and R 3 are each independently COOR 1 or R, and at least one of R 2 and R 3 is COOR 1 ; na single bond (excluding C a -C a bonds, and a C a -C b bond in the case where R 3 is R) in the cyclic backbone may be replaced with a double bond; na plurality of R 1 's are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms; and na plurality of R' s are each independently a hydrogen atom or a substituent, but at least one of R's is not a hydrogen atom. When using this solid titanium catalyst component (I), an olefin polymer having a broad molecular weight distribution can be produced. |