US4522982A
Expired / Lapsed
US
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Isotactic-stereoblock polymers of alpha-olefins and process for producing the same
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1983-06-06
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Granted: 1985-06-11
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Expires: 2003-06-06
Abstract
Abstract Isotactic-stereoblock polypropylene comprising recurring polypropylene units, said isotactic-stereoblock polypropylene characterized by comprising alternating blocks of monomers having an average block length greater than 2 having methine carbons with the same relative configuration and wherein the methine carbon atoms in adjacent blocks are of opposite configuration.
Inventors
- 👤 John A. Ewen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:41
CPC Classifications
C; C08; C08F; C08F110/00; C08F110/04; C08F110/06; Y; Y10; Y10S; Y10S526/00; Y10S526/943
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
47 words
Normally solid isotactic-stereoblock polypropylene comprising recurring polypropylene units, said isotactic-stereoblock polypropylene characterized by comprising alternating blocks of monomers having an average block length greater than 2 having methine carbons with the same relative configuration and wherein the methine carbon atoms in adjacent blocks are of opposite configuration.
Claim 2
Dependent Claim
47 words
Normally solid isotactic-stereoblock polypropylene comprising recurring polypropylene units, said isotactic-stereoblock polypropylene characterized by comprising alternating blocks of monomers having an average block length greater than 2 having methine carbons with the same relative configuration and wherein the methine carbon atoms in adjacent blocks are of opposite configuration.
Claim 3
Dependent Claim
18 words
Isotactic-stereoblock polypropylene of claim 1 wherein the average block length contains from about 3 to 50 repeating units.
Claim 4
Dependent Claim
17 words
Isotactic-stereoblock polypropylene of claim 2 wherein the average block length contains from 5 to 17 repeating units.
Claim 5
Dependent Claim
12 words
Isotactic-stereoblock polypropylene of claim 1 having a molecular weight greater than 200.
Claim 6
Dependent Claim
9 words
Isotactic-stereoblock polypropylene of claim 4 which is normally solid.
Claim 7
Dependent Claim
14 words
Mixtures of crystalline polymers of an alpha-olefin with the isotactic-stereoblock polypropylene of claim 1.
Claim 8
Dependent Claim
12 words
The mixture of claim 6 wherein the crystalline polymer is isotactic polypropylene.
Claim 9
Dependent Claim
78 words
The process of polymerizing propylene to normally solid isotactic-stereoblock polypropylene, said normally solid isotactic-stereoblock polypropylene comprising alternating blocks of monomers having an average block length greater than 2 and having methine carbons with the same relative configuration and wherein the methine carbon atoms in adjacent blocks have opposite relative configurations, the process comprising polymerizing propylene in the presence of a homogeneous catalyst system comprising a metallocene and an alumoxane at a temperature of less than about 0° C.
Claim 10
Dependent Claim
78 words
The process of polymerizing propylene to normally solid isotactic-stereoblock polypropylene, said normally solid isotactic-stereoblock polypropylene comprising alternating blocks of monomers having an average block length greater than 2 and having methine carbons with the same relative configuration and wherein the methine carbon atoms in adjacent blocks have opposite relative configurations, the process comprising polymerizing propylene in the presence of a homogeneous catalyst system comprising a metallocene and an alumoxane at a temperature of less than about 0° C.
Claim 11
Dependent Claim
12 words
The polymerization process of claim 8 wherein the metallocene is a titanocene.
Claim 12
Dependent Claim
16 words
The polymerization process of claim 9 wherein the polymerization temperature is less than about -30° C.
Claim 13
Dependent Claim
20 words
The polymerization process of claim 10 wherein the polymerization temperature is in the range of -60° C. to -30° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-06-10 | 1988-12-10 | 1989-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-10 | 1992-12-10 | 1993-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-10 | 1996-12-10 | 1997-06-11 | $7700.00 | Window Closed / Lapsed |