US4310484A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for extruding molten narrow molecular weight distribution, linear, ethylene copolymers
Assignee: Union Carbide Corp
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Filing: 1980-08-01
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Granted: 1982-01-12
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Expires: 2000-08-01
Abstract
Abstract A method for extruding granular low density narrow molecular weight distribution linear ethylene polymers which comprises passing said granular polymers into an extrusion apparatus including an extruder screw, said extruder screw having a feed section wherein said polymers are introduced and thence passed through a transition section and a metering section, wherein each lead in the feed section is substantially the same and each lead in the metering section is substantially the same and wherein each lead in the feed section is 5 to 50 percent greater than each lead in the metering section.
Inventors
- 👤 Theodore R. Blakeslee, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:24
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/36; B29C48/50; B29C48/505; B29C48/53; B29C48/022; B29C48/03; B29C48/07; B29C48/08; B29C48/09; B29C48/10; B29K; B29K2023/00; B29K2023/04; B29K2023/06; B29K2023/0608; B29K2023/0633
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
94 words
A method for extruding granular low density narrow molecular weight distribution linear ethylene polymers which comprises passing said granular polymers into an extrusion apparatus including an extruder screw, said extruder screw having a feed section wherein said polymers are introduced and thence passed through a transition section and a metering section, wherein each lead in the feed section is substantially the same and each lead in the metering section is substantially the same and wherein each lead in the feed section is 5 to 50 percent greater than each lead in the metering section.
Claim 2
Independent Claim
94 words
A method for extruding granular low density narrow molecular weight distribution linear ethylene polymers which comprises passing said granular polymers into an extrusion apparatus including an extruder screw, said extruder screw having a feed section wherein said polymers are introduced and thence passed through a transition section and a metering section, wherein each lead in the feed section is substantially the same and each lead in the metering section is substantially the same and wherein each lead in the feed section is 5 to 50 percent greater than each lead in the metering section.
Claim 3
Dependent Claim
24 words
A method according to claim 1 wherein said lead in the feed section is 15-30 percent greater than each lead in the metering section.
Claim 4
Dependent Claim
28 words
A method according to claim 1 wherein the lead change between the feed section and the metering section is accomplished by an abrupt change in the transition section.
Claim 5
Dependent Claim
22 words
A method according to claim 3 wherein said lead change in the transition section is at the beginning of said transition section.
Claim 6
Dependent Claim
31 words
A method according to claim 1 wherein the lead change between the feed section and the metering section is accomplished by an abrupt change at the beginning of the metering section.
Claim 7
Dependent Claim
29 words
A method according to claim 1 wherein the depth of the material channel in the metering section is smaller than the depth of the channel in the feed section.
Claim 8
Dependent Claim
36 words
A method according to claim 1 in which said polymer is a copolymer of ethylene and at least one C 3 to C 8 alpha olefin having a melt index of about ≧0.1 to about ≦20.
Claim 9
Dependent Claim
33 words
A method according to claim 7 in which said polymer is a copolymer of ≧90 mol percent ethylene and ≦10 mol percent of at least one C 3 to C 8 alpha olefin.
Claim 10
Dependent Claim
33 words
A method according to claim 8 in which said copolymer has a molecular weight distribution of about ≧2.7 to ≦6.0 and a total unsaturation content of about ≧0.1 to ≦0.3 C=C/1000 C atoms.
Claim 11
Dependent Claim
33 words
A method according to claim 8 in which said copolymer has a melt flow ratio of about ≧22 to ≦40 and a total unsaturation content of about ≧0.1 to ≦0.3 C=C/1000 C atoms.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-01-11 | 1985-07-13 | 1986-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-01-11 | 1989-07-13 | 1990-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-01-11 | 1993-07-13 | 1994-01-12 | $7700.00 | Window Closed / Lapsed |