US5066738A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymerization of olefins with an improved catalyst system using a new electron donor
Assignee: Toho Titanium Co Ltd
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Filing: 1990-04-20
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Granted: 1991-11-19
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Expires: 2010-04-20
Abstract
Abstract The present invention provides a catalyst system that exhibits unprecedented catalyst efficiencies and control of desired properties in the polymer product. The catalyst system includes a new generation titanium catalyst in combination with an electron donor described by the formula: ##STR1## wherein R 1 is bulky, basic alkyl or cycloalkyl group containing at least one secondary or tertiary carbon atom; R 2 and R 3 are alkyl or aryl groups; and R 4 is an alkyl group with a primary carbon atom attached to the silicon atom. The system has a catalyst efficiency of at least about 30 kg/g-cat.2h as the Al/Si mole ratio varies from 20-200 in the system. The system easily achieves efficiencies over 60 kg/g-cat.2h. The system also exhibits good control over the xylene solubles, melt flow and molecular weight distribution of the polymer product.
Inventors
- 👤 John A. Ewen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:58
CPC Classifications
C; C08; C08F; C08F10/00; Y; Y10; Y10S; Y10S526/00; Y10S526/904
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
185 words
A process for the polymerization of olefins, comprising: (a) preparing a solid catalyst component by: (i) suspending a dialkoxy magnesium in an aromatic hydrocarbon that is liquid at normal temperatures, (ii) contacting the dialkoxy magnesium with a titanium halide and further contacting the resulting composition a second time with the titanium halide, and (iii) contacting the dialkoxy magnesium with a diester of an aromatic dicarboxylic acid at some point during the treatment with the titanium halide in (ii); (b) contacting the catalyst component with an organoaluminum compound; (c) contacting said catalyst component with an electron donor either simultaneously with or after step (b) to form a catalyst system, said electron donor being described by the formula: ##STR5## wherein R 1 is a bulky, alkyl or cycloalkyl group containing at least one secondary or tertiary carbon atom; R 2 and R 3 are each independently an alkyl or aryl group; and R 4 is an alkyl group with a primary carbon atom attached to the silicon atom; (d) introducing said catalyst system into a polymerization reaction zone containing an olefin monomer; and (e) polymerizing said monomer.
Claim 2
Dependent Claim
185 words
A process for the polymerization of olefins, comprising: (a) preparing a solid catalyst component by: (i) suspending a dialkoxy magnesium in an aromatic hydrocarbon that is liquid at normal temperatures, (ii) contacting the dialkoxy magnesium with a titanium halide and further contacting the resulting composition a second time with the titanium halide, and (iii) contacting the dialkoxy magnesium with a diester of an aromatic dicarboxylic acid at some point during the treatment with the titanium halide in (ii); (b) contacting the catalyst component with an organoaluminum compound; (c) contacting said catalyst component with an electron donor either simultaneously with or after step (b) to form a catalyst system, said electron donor being described by the formula: ##STR5## wherein R 1 is a bulky, alkyl or cycloalkyl group containing at least one secondary or tertiary carbon atom; R 2 and R 3 are each independently an alkyl or aryl group; and R 4 is an alkyl group with a primary carbon atom attached to the silicon atom; (d) introducing said catalyst system into a polymerization reaction zone containing an olefin monomer; and (e) polymerizing said monomer.
Claim 3
Dependent Claim
11 words
The process of claim 1 wherein said organoaluminum compound is triethylaluminum.
Claim 4
Dependent Claim
14 words
The process of claim 1 wherein R 1 is a cyclohexyl or t-butyl group.
Claim 5
Dependent Claim
10 words
The process of claim 1 wherein said monomer is propylene.
Claim 6
Dependent Claim
11 words
The process of claim 1 wherein said electron donor is methylcyclohexyldimethoxysilane.
Claim 7
Dependent Claim
50 words
The process of claim 1 wherein said process is characterized by a catalyst efficiency of at least about 30 kg of polymer product per gram of catalyst in two hours with the mole ratio of Al/Si from the organoaluminum compound and the silicon electron donor within the range of 20-200.
Claim 8
Dependent Claim
33 words
The process of claim 1 wherein said process is characterized by producing a polymer product in which the xylene soluble portion is within the range of 2-10 wt % of the polymer product.
Claim 9
Dependent Claim
19 words
The process of claim 1 further comprising the addition of a second monomer so as to form a copolymer.
Claim 10
Dependent Claim
28 words
The process of claim 1 further comprising: between steps (c) and (d), pre-polymerizing said catalyst system by contacting a small amount of said monomer with said catalyst system.
Claim 11
Dependent Claim
34 words
The process of claim 1 further comprising: step (d) modified by introducing said catalyst system into a polymerization reaction zone containing additional amounts of said organoaluminum compound, said electron donor and an olefin monomer.
References Cited (Backward Citations)
US4295991A
Cited
US4816433A
Cited
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| 3.5 Years (Year 4) | 1994-11-18 | 1995-05-20 | 1995-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-18 | 1999-05-20 | 1999-11-19 | $3760.00 | Window Closed / Lapsed |
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