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(19) Japanese Patent Office (JP)			(12) Publication of Unexamined Patent Application (A)				(11) Disclosure Number: Hei 04-69394
(51) Int. Cl.⁵ C07F 17/00 B01J 31/22 C07F 7/00 C08F 4/645 C08F 10/00		Identification Code			Internal Agency Classification No. C07F 17/00 B01J 31/22 C07F 7/00 C08F 4/645 C08F 10/00	(43) Date of Disclosure: 1992.03.04
	Examination Request Status: Not yet requested. No. of Inventions: 2 (8 pages total)
(54) Title of Invention: Novel Transition Metal Compound and Syndiotactic Poly-a-olefin Manufacturing Method Using Said Compound
				(21) Filing Number: Hei 02-179563 (22) Date of Application: 1990.07.09
(71) Assignee: Mitsui Toatsu Chemicals, Inc. 3-2-5 Kasumigaseki Chiyoda-ku, Tokyo (72) Inventor: Norihide Inoue 2882 Iijima-cho Sakae-ku Yokohama-shi, Kanagawa-ken (72) Inventor: Tetusnosuke Shiomura 4-22-1-304 Yoyogi Shibuya-ku, Tokyo (72) Inventor: Masahiro Kouno 1934 Manazuru, Manazuru-machi Ashigara Shimo-gun, Kanagawa-ken (72) Inventor: Yoshiho Sonobe 2070 Iijima-cho, Sakae-ku Yokohama-shi, Kanagawa-ken (72) Inventor: Kazumi Mizutani 8-502 Kowan Jutaku 5 Nishiki-cho, Nakano-ku Yokohama-shi, Kanagawa-ken

Summary

1. Title of the Invention

Novel Transition Metal Compound and Syndiotactic Poly-a-olefin Manufacturing Method Using Said Compound

2. Scope of the Patent Claims

[Claim 1] A novel transition metal compound represented by general formula (1).

(wherein C₅H₄ is a cyclopentadienyl group; A¹ is a disubstitued fluorenyl group; A² is a C₄ - C₂₀ hydrocarbon group that gives rise to a bridging structure between the cyclopentadienyl group and the disubstitued fluorenyl group; R₁, R₂ is a halogen atom, a C₁ - C₁₀ alkyl group or aryl group; and M is titanium, zirconium, or hafnium.)

[Claim 2] A method for the manufacture of a syndiotactic poly-a-olefin; the method comprising polymerization of an a-olefin using the transition metal compound of Claim 1 in the presence of a co-catalyst that is an aluminoxane or a boron compound.

3. Detailed Description of the Invention

[Industrial Field of Application] The present invention pertains to a novel transition metal compound and a method for the manufacture of a poly-a-olefin utilizing this compound as a catalyst component.

[Conventional Technology]

It has long been known that vanadium compounds can be used as catalysts for the manufacture of syndiotactic poly-a-olefins. However use of the earlier technology catalyst, consisting of a vanadium compound and an organoaluminum compound, results in a polymer that has poor syndiotacticity. This polymer can not be said to exhibit the characteristics of a syndiotactic poly-a-olefin.

In contrast, Publication of Unexamined Patent Application No. Hei 2-41303 reveals a metallocene compound that is used together with an aluminoxane as a catalyst, making possible a-olefin polymerization to form a highly syndiotactic polypropylene. This metallocene compound has the following formula.

R” (Cp R_n) (Cp R’_m) Me Q_k

Here, Cp is a cyclopentadienyl group or a substituted cyclopentadienyl ring. Each R_n group is identical or different, and R_n is a C₁ - C₂₀ hydrocarbyl group. R” forms a bridging structure between the Cp rings, thereby imparting 3-dimensional rigidity to the catalyst. Me is a metallic element from the 4b, 5b, or 6b groups of the periodic table. Q_k is a C₁ - C₂₀ hydrocarbyl group or a halogen. 0 ³ k ³ 3, 0 ³ n ³ 4, and 1 ³ m ³ 4. R’_m is selected so that (Cp R_s) and (Cp R’_m) are asymmetric. [TRANSLATOR’S NOTE: R_s is probably a typo for R_n, and ³ is probably a typo for £.]

However, this same unexamined patent application reveals only a catalyst that consists of a hafnium compound together with a zirconium compound that has an isopropylidene (cyclopentadienyl-9-fluorenyl) group ligand. This unexamined patent application makes no mention whatsoever of the synthesis and properties of a transition metal compound that has a disubstitued fluorenyl group.

Publication of Unexamined Patent Application No. Sho 64-66214 reveals a catalyst composition that includes a component that has at least one fluorenyl or fluorenyl derivative ligand. This publication reveals the use of this catalyst composition for a-olefin polymerization or copolymerization. However, the disclosed compound does not catalyze the formation of a syndiotactic poly-a-olefin.

[Problems Solved by the Invention]

In the above-mentioned Publication of Unexamined Patent Application No. Hei 2-41303, use of a catalyst composition (consisting of a transition metal compound, that has a isopropylidene (cyclopentadienyl-9-fluorenyl) group ligand, together with the aluminoxane co-catalyst) resulted in good polymerization reactivity. Although a polypropylene could be obtained that was highly syndiotactic, the resultant polypropylene crystallized slowly so that processing and molding were difficult.

[Means to Solve the Problems]

The inventors of the present invention discovered the present invention after carrying out investigations into the synthesis of a novel compound catalyst composition that could be used for the manufacture of a syndiotactic poly-a-olefin with high reactivity, thereby solving the above-mentioned problems.

Specifically, the present invention is a novel transition metal compound represented by general formula (I).

(where C₅H₄ is a cyclopentadienyl group; A¹ is a disubstitued fluorenyl group; A² is a C₄ - C₂₀ hydrocarbon group that gives rise to a bridging structure between the cyclopentadienyl group and the disubstitued fluorenyl group; R₁, R₂ is a halogen atom, a C₁ - C₁₀ alkyl group, or a C₁ - C₁₀ aryl group; and M is titanium, zirconium, or hafnium.)

C₅H₄ within the formula for the transition metal compound (I) of the present invention is a cyclopentadienyl group. A¹ in the formula, as indicated by formula (II), is a disubstitued fluorenyl group.

(where A³ is a C₁ - C₁₀ linear or branched alkyl group, preferably a C₂ - C₆ linear or branched alkyl group)

Specific examples of A¹ include a 2,7-diethyl-9-fluorenyl group, a 2,7-diisopropyl-9-fluorenyl group, a 2,7-di-t-butyl-9-fluorenyl group, a 2,7-diisobutyl-9-fluorenyl group, a 2,7-diisopentyl-9-fluorenyl group, a 3,6-diethyl-9-fluorenyl group, a 3,6-di-t-butyl-9-fluorenyl group, a 3,6-diisobutyl-9-fluorenyl group, a 3,6-diisopentyl-9-fluorenyl group, etc. ...

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