A catalyst composition comprises an inert hydrocarbon solvent, having dissolved therein a titanate of the formula Ti(OR).sub.4 wherein each R is the same or different, and is a hydrocarbon residue, and an organic aluminum compound, wherein a molar ratio of the organic aluminum compound and any alkene present in the catalyst composition is greater than one.

Provided are a system for producing a polyolefin, a method of producing a polyolefin, and a method of producing a heterophasic propylene polymer material, each of which allows (i) a gel, to be contained in a molded product that is made of an obtained polyolefin, to be reduced and (ii) a polyolefin to be continuously produced stably. A polyolefin producing system (1) includes: a cylindrical member which extends in a vertical direction; diameter decreasing members each of which is provided to the cylindrical member, each of the diameter decreasing members having (i) an inner diameter that decreases as the each of the diameter decreasing members extends downward and (ii) a gas inlet opening at a lower end of the each of the diameter decreasing members; spouted bed type olefin polymerization reaction regions (25) each of which is surrounded by (a) an inner surface of a corresponding one of the diameter decreasing members and (b) part of an inner surface of the cylindrical member which part extends upward from the corresponding one of the diameter decreasing members, each of the spouted bed type olefin polymerization reaction regions (25) being a region in which a spouted bed is formed, the number of the spouted bed type olefin polymerization reaction regions (25) being 3 or more; and at least one fluidized bed type olefin polymerization reaction region which is provided at a stage subsequent to the spouted bed type olefin polymerization reaction regions (25).

Provided are a catalyst composition and a method of oligomerizing olefins using the same. When the catalyst composition according to the present invention is used, oligomerization and copolymerization of olefin monomers may be performed in a single reactor at the same time with high efficiency without a separate process of preparing alpha-olefin. Therefore, costs for preparing or purchasing comonomers which are expensive raw materials may be reduced, thereby reducing the production cost of a final product. Contents of SCB (short chain branch) and LCB (long chain branch) in the polyolefin may be increased without separate feeding of comonomers, thereby producing high-quality linear low-density polyethylene.

A catalyst comprising a NCN pincer ligand group VI complex is capable of being used as an olefin polymerization or isomerization catalyst that does not require an expensive cocatalyst. The complex has the NCN pincer ligand in a trianionic form with the group VI in the +3 oxidation state or the +4 oxidation state and complexed to an anionic hydrocarbon group, or the complex has the NCN pincer ligand in a dianionic form with the group VI in the +2 oxidation state. The complex is capable of initiating the polymerization of alkenes without an added activator. The presence of a water scavenger and activator or cocatalyst, such as triisobutylaluminum, increases the catalytic activity. The complex is capable of selectively isomerizing 1-alkenes to cis/trans 2-alkenes.

The present invention is concerned with a catalyst composition comprising titanium-, zirconium- and/or hafnium amidinate complexes and/or titanium-, zirconium- and/or hafnium guanidinate complexes and organo aluminium and/or organic zinc compounds, a coordinative chain transfer polymerization (CCTP) process employing the catalyst composition as well as long chain aluminium alkyls and subsequent alcohols obtained by such process.

Processes of preparing freeze-dried co-catalyst compositions are provided. In an exemplary embodiment, the process includes mixing an organoaluminum compound with a modifier at low temperature to provide a modified co-catalyst composition. The process further includes further cooling the modified co-catalyst composition under reduced pressure, to provide a freeze-dried co-catalyst composition. Processes of preparing freeze-dried catalyst compositions, processes of preparing catalyst compositions, freeze-dried co-catalyst compositions, freeze-dried catalyst compositions, catalyst compositions, and processes of preparing -olefins are also provided.

A catalyst composition comprises an inert hydrocarbon solvent, having dissolved therein a titanate of the formula Ti(OR).sub.4 wherein each R is the same or different, and is a hydrocarbon residue, and an organic aluminum compound, wherein a molar ratio of the organic aluminum compound and any alkene present in the catalyst composition is greater than one.