Olefin polymerization catalyst and process for preparing polyolefins

摘要

According to the present invention, there are provided a catalyst and a process for the preparation of polyolefins having a relatively wide molecular weight distribution, good particle properties, a narrow composition distribution in copolymerization and a high molecular weight and being less sticky. The catalyst is prepared by contacting the following constituents (1) to (4) with one another: (1) a compound represented by the general formula Me<1>R<1>p(OR<2>)qX4-p-q, where Me<1> is Zr, Ti or Hf, R<1> and R<2> are each independently a hydrocarbon group having 1 to 24 carbon atoms, X is a halogen atom, p and q are each an integer in the ranges of 0 </= p </= 4 and 0 </= q </= 4, provided 0 </= p+q </= 4; (2) a compound represented by the general formula Me<2>R<3>m(OR<4>)nX<2>z-m-n, where Me<2> is a Group I-III element in the Periodic Table, R<3> and R<4> are each independently a hydrocarbon group having 1 to 24 carbon atoms, X<2> is a halogen atom or a hydrogen atom, provided when X<2> is a hydrogen atom, Me<2> is a Group III element in the Periodic Table, z is the valence of Me<2>, m and n are each an integer in the ranges of 0 </= m </= z, and 0 </= n </= z, provided 0 </= m+n </= z; (3) an organocyclic compound having conjugated double bonds; and (4) a modified organoaluminum compound containing A1-O-Al bond, and thereafter contacting the resulting contact reaction product with the following component (5): (5) an inorganic carrier and/or a particulate polymer carrier.