Catalysts for olefin polymer production and process for...

Details Catalysts for olefin polymer production and process for... Catalysts for olefin polymer production and process for...

1999-12-13

2002-01-01

Lipman, Bernard (Department: 1713)

Synthetic resins or natural rubbers -- part of the class 520 ser

Synthetic resins

Polymers from only ethylenic monomers or processes of...

C526S129000, C526S155000, C526S171000, C526S352000, C502S117000, C502S118000, C502S132000, C502S108000, C502S104000

Reexamination Certificate

active

06335405

ABSTRACT:

TECHNICAL FIELD
The present invention relates to catalysts for olefin polymer production and to a method for producing olefin polymers. More precisely, it relates to novel catalysts with which practical high-melting-point and high-molecular-weight olefin polymers, especially polyethylenes are produced efficiently, inexpensively, and industrially advantageously, and to a method of using the catalysts for olefin polymer production.
BACKGROUND OF THE INVENTION
As catalysts for olefin polymer production, at present, mainly used are Ziegler catalysts and metallocene catalysts, which comprise, as the essential catalyst component, a compound of a metal element of Group 4 of the Periodic Table such as titanium or zirconium. Of metallocene catalysts, those comprising metallocene and aluminoxane are much used (Japanese Patent Laid-Open Nos. 19309/1983, 167307/1990, etc.) . As compared with that of Ziegler catalysts, the polymerization activity of such metallocene catalysts, relative to the transition metal therein, is extremely high. Using metallocene catalysts gives polymers having a narrow molecular weight distribution.
On the other hand, recently, novel catalysts comprising a metal complex with a metal of Groups 8 to 10 of the Periodic Table, such as typically nickel or palladium, have been developed, apart from the catalysts noted above. Heretofore, nickel complexes have been known as oligomerization catalysts for olefins, and it is said that they are unsuitable to polymer formation.
Regarding the techniques that relate to such catalysts comprising a nickel or palladium complex, various proposals have heretofore been made, including, for example, (1) a method of using a catalyst that comprises an Ni(O) complex as coordinated with an adduct of quinone and a tertiary phosphine, for ethylene polymerization (Japanese Patent Publication No. 1796/1993); (2) a catalyst comprising an Ni(O) complex, an adduct of maleic anhydride and a tertiary phosphine, a phosphorus ylide, and an organic aluminium compound (Japanese Patent Laid-Open No. 203106/1986); (3) a catalyst comprising an Ni(O) or Ni(II) complex and an iminophospholane compound (Japanese Patent Laid-Open No. 115311/1991); (4) a method of using a borate complex with a metal of Group 8 to 10 (Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, or Pt) coordinated with a cis-type chelate ligand, for ethylene polymerization; (5) a catalyst comprising an Ni(O) complex, an adduct of an imide and a tertiary phosphine, and a phosphine oxide (Japanese Patent Laid-Open No. 122721/1994); (6) a catalyst comprising a combination of a complex of Pd(II) with BF
4
−
and methylaluminoxane (Japanese Patent Laid-Open No. 82314/1995); (7) a catalyst comprising an Ni(II) complex, an iminophospholane compound and an organic aluminium compound (Japanese Patent Laid-Open No. 277610/1991); (8) a catalyst comprising an Ni(O) or Ni(II) complex and an iminophospholane compound having a bulky substituent (Japanese Patent Laid-Open No. 25932/1995); (9) a catalyst comprising a combination of a complex of Ni(II) with a phosphorus-oxygen chelate and a linear or cyclic aluminium compound (Japanese Patent Laid-Open No. 14217/1989), etc.
However, the above techniques of (1) to (8) for ethylene polymerization are all problematic in that they require an extremely high reaction pressure (for example, 100 kg/cm
2
), that the catalysts indispensably contain a phosphorus-containing compound which will remain in the polymers formed to have some negative influences on the resinous properties of the polymers, and that expensive methylaluminoxane is indispensable for expressing the catalyst activity.
Precisely, the drawbacks to the ethylene polymerization method of (1) are that the reaction pressure is extremely high (for example 100 kg/cm
2
) and that the catalyst activity to produce polyethylene is extremely low (about 6 kg/g—Ni·hr); and those to (2) are that the catalyst is for polymerization of high pressure ethylene, and is complicated as comprising many components, and that the catalyst activity is extremely low (at most about 1 kg/g—Ni·hr). The drawbacks to the others are as follows. For the catalyst of (3), the reaction pressure may be low, but the catalyst activity is extremely low (at most about 1 kg/g—Ni·hr). Also in the ethylene polymerization of (4), the catalyst activity is extremely low (at most about 0.1 kg/g—Ni·hr). The catalyst of (5) has a low activity (about 5 kg/g—Ni·hr). Though containing a cationic complex, the catalyst of (6) requires expensive methylaluminoxane for expressing its activity, and, in addition, its activity is low (at most about 3 kg/g—Ni·hr). The catalysts of (7) and (8) both have an extremely low activity (at most about 5 kg/g—Ni·hr). The catalyst (9) requires expensive methylaluminoxane serving as a catalyst promoter, and, in addition, its activity is low though the reaction pressure to be related to the activity is high (for example, about 20 kg/g—Ni·hr under 30 kg/cm
2
G).
Recently, catalysts comprising a combination of a nitrogen-containing ligand complex, for example, a diimine complex with a metal of Groups 8 to 10, such as typically nickel or palladium, and an organic aluminium compound such as methylaluminoxane (MAO) or the like, and those comprising a combination of such a nitrogen-containing ligand complex and an anion seed of, for example, BF4
−
, PF6
−
, SbF6
−
, or BAF
−
[tetrakis(3,5-bistrifluoromethylphenyl)borate] have been proposed. For example, catalysts of the following [3] and [2] have been disclosed (International Patent Laid-Open No. 96/23010).
These catalysts have an extremely high activity for ethylene polymerization, as compared with the catalysts noted above, and, in addition, the polymers produced with them are characterized by having a poly-branched structure. However, these catalysts can be used only at low temperatures, and the molecular weight of the polymers produced with them is low. Therefore, these catalysts are not as yet practicable.
Moreover, metallocene/aluminoxane catalysts, and nitrogen-containing ligand complex with metal of Group 8 to 10/aluminoxane catalysts are still problematic in that they require a large amount of an aluminoxane in order to ensure sufficiently high polymerization activity. In particular, they require methylaluminoxane which is expensive and is not easy to handle and which is not stable during storage and is highly dangerous. Therefore, the polymerization efficiency with them is poor and, in addition, removing the catalyst residue from the polymers produced is indispensable.
Further, the method of using aluminoxane is problematic in that the polymers produced often adhere to the walls of reactors, and the polymer adhesion will be a bar to safe operation.
Another proposal for metallocene catalysts for olefin polymerization has been made, which is to add clay, a clay mineral or an ion-exchanging layered compound to the catalysts (Japanese Patent Laid-Open No. 301917/1993).
However, a catalyst comprising a combination of any of such additives and a nitrogen-containing ligand complex with a metal of Groups 8 to 10, with which the structure of the polymers produced differs from that of the polymers to be produced with the metallocene catalysts, is not known. In addition, in the proposed method, it is said the clay mineral to be used must be indispensably pre-treated with expensive and dangerous trimethylaluminium. Further, the proposed method is problematic in that the catalyst activity per aluminium is not so high and that the amount of the catalyst residue to remain in the polymers produced is large.
Given that situation, the present invention has its object to provide a novel catalyst for olefin polymerization to give polyolefins especially polyethylene having a high melting point or having a high molecular weight to be on a practicable level, and to provide a method of using the catalyst for olefin polymer production. The catalyst does not contain a large amount of methylaluminoxane which is expensive and is not easy to handle and whic

Affiliated with

Also associated with

Rating

Catalysts for olefin polymer production and process for... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Catalysts for olefin polymer production and process for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Catalysts for olefin polymer production and process for... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2842836