US3898209A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for controlling rheology of C{HD 3{B {30 {0 polyolefins
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1973-11-21
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Granted: 1975-08-05
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Expires: 1993-11-21
Abstract
Abstract The rheology of C3+ polyolefins, e.g. polypropylene can be economically and conveniently controlled by injecting under pressure certain critical quantities of oxygen in an inert gas, e.g., air into melted polymer as it is being processed within an extruder.
Inventors
- 👤 Albert T Watson
- 👤 Hulen L Wilder
- 👤 Kenneth W Bartz
- 👤 Robert A Steinkamp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:10
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/50; B; B29; B29C; B29C48/00; B29C48/022; B29C48/25; B29C48/285; B29C48/29; B29C48/03; B29C48/05; B29C48/07; B29C48/08; B29K; B29K2105/00; B29K2105/0005; C08F2810/00; C08F2810/10
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
155 words
IN THE PROCESS FOR THE CONTROLLED SCISSION OF POLYPROPYLENE HAVING A SHARE STRESS ABOVE 22 AND A DIE SWELL OF FROM 1 TO 12 IN CONFORMANCE WITH THE STRATING POLYMERS DESIGNATED ON THE VSCOELASTIC GRID IN AN EXTRUDER-REACTURE IN WHICH MOLTEN POLYPROPYLENE IS CONVEYED UNDER SHEAR THROUGH A MIXING ZONE, A RACTOR ZONE, AND A METERING ZONE, IN SAID EXTRUDER-REACTOR, THE IMPROVEMENT IN EFFECTING RHEOLOGY CHANGES IN SAID POLYPROPLENE WHICH COMPRISES. THE HIGH PRESSURE INJECTION OF GAS CONTAINING FROM 15 TO 25 WT. PERCENT OXYGEN UNDER PRESSURE INTO SAID METERING ZONE AT A RATE OF 500 TO 5000 CC OF SAID GAS PER POUND OF SAID MOLTEN POLYPROPYLENE, WHEREIN SAID METERING ZONE IS MAINTAINED AT A TEMPERATURE OF ABOUT 50* TO 400F. LOWER THAN THE TEMPERATURE OF SAID REACTOR ZONE WHEREBY CRITICAL END-USE SPECIFICATIONS OF DIE SWELL, MFR AND SHEAR STRESS CAN BE MET WITH NOT MORE THAN PASSES OF SAID POLYPROPYLENE THROUGH SAID EXTRUDER-REACTOR.
Claim 2
Dependent Claim
155 words
IN THE PROCESS FOR THE CONTROLLED SCISSION OF POLYPROPYLENE HAVING A SHARE STRESS ABOVE 22 AND A DIE SWELL OF FROM 1 TO 12 IN CONFORMANCE WITH THE STRATING POLYMERS DESIGNATED ON THE VSCOELASTIC GRID IN AN EXTRUDER-REACTURE IN WHICH MOLTEN POLYPROPYLENE IS CONVEYED UNDER SHEAR THROUGH A MIXING ZONE, A RACTOR ZONE, AND A METERING ZONE, IN SAID EXTRUDER-REACTOR, THE IMPROVEMENT IN EFFECTING RHEOLOGY CHANGES IN SAID POLYPROPLENE WHICH COMPRISES. THE HIGH PRESSURE INJECTION OF GAS CONTAINING FROM 15 TO 25 WT. PERCENT OXYGEN UNDER PRESSURE INTO SAID METERING ZONE AT A RATE OF 500 TO 5000 CC OF SAID GAS PER POUND OF SAID MOLTEN POLYPROPYLENE, WHEREIN SAID METERING ZONE IS MAINTAINED AT A TEMPERATURE OF ABOUT 50* TO 400F. LOWER THAN THE TEMPERATURE OF SAID REACTOR ZONE WHEREBY CRITICAL END-USE SPECIFICATIONS OF DIE SWELL, MFR AND SHEAR STRESS CAN BE MET WITH NOT MORE THAN PASSES OF SAID POLYPROPYLENE THROUGH SAID EXTRUDER-REACTOR.
Claim 3
Dependent Claim
11 words
The process according to claim 1 wherein said polymer is polypropylene.
Claim 4
Dependent Claim
19 words
The process according to claim 1 wherein said temperature in said metering zone is about 350* to 500* F.
Claim 5
Dependent Claim
16 words
The process according to claim 1 wherein said polymer is processed in such manner only once.
Claim 6
Dependent Claim
47 words
A process according to claim 1 wherein said polymer is polypropylene, said gas is air, said temperature is 350* to 500* F. and said air is injected at a pressure of 1,200 to 5,000 psig at a rate of 500 to 5,000 cc per pound of polypropylene.
Claim 7
Dependent Claim
14 words
A method according to claim 5 wherein said procedure is carried out only once.
Claim 8
Dependent Claim
25 words
A method according to claim 1 wherein said resulting polymer has a die swell of -0.5 to 2 and a MFR of 20 to 50.
Claim 9
Dependent Claim
25 words
A method according to claim 1 wherein said resulting polymer has a die swell of 2 to 4 and a MFR of 4 to 9.
Claim 10
Dependent Claim
25 words
A method according to claim 1 wherein said resulting polymer has a die swell of 0.1 to 4 and an MFR of 40 to 60.
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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) | 1978-08-04 | 1979-02-03 | 1979-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-04 | 1983-02-03 | 1983-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-04 | 1987-02-03 | 1987-08-05 | $7700.00 | Window Closed / Lapsed |