US3925341A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for working up particulate polyolefins obtained by polymerization carried out with the aid of ziegler/natta catalysts
Assignee: BASF SE
•
Filing: 1973-11-26
•
Granted: 1975-12-09
•
Expires: 1993-11-26
Abstract
Abstract A process for working up particulate polyolefins obtained by polymerization carried out with the aid of Ziegler/Natta catalysts. The process of the invention is characterized by a continuous, conventional operation (1) comprising the following integrated sub-stages: (1.1) introducing particulate polyolefin to a melting zone, (1.2) passing the molten polyolefin to a degassing zone, (1.3) transferring the degassed polyolefin to a discharge zone, and (1.4) finally extruding and granulating the resulting polyolefin; and by an important, additional and new feature (2) comprising the addition of an alkenoxide, water and optionally nitrogen to the polyolefin immediately before it passes to the melting zone or while it is in the melting zone. This process makes it possible to produce granular polyolefins of low halogen content in a particularly simple manner.
Inventors
- 👤 Heinz Mueller-Tamm
- 👤 Hannes Schick
- 👤 Wolfgang Rau
- 👤 Peter Hennenberger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:18
CPC Classifications
C; C08; C08F; C08F6/00; C08F6/02; C08F8/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
77 words
A PROCESS FOR WORKING UP PARTICULATE POLYOLEFINS IN AN EXTRUDE SAID PARTICULATE POLYOLEFINS HAVING BEEN OBTAINED BY GAS PHASE POLYMERIZATION WITH THE AID OF ZIEGLER/NATTA CATALYSTS AND HAVING A PARTICLE DIAMETER OF LESS THAN 5 MM. SAID PROCESS CONSISTING ESSENTIALLY OF: A. CONTINUOUSLY INTRODUCING SAID PARTICULATE POLYOLEFIN INTO A MELTING ZONE HWEREIN SUFFICIENT HEAT IS APPLIED TO MELT SAID POLYOLEFIN; B. ADDING TO SAID PARTICULATE POLYOLEFIN BEFORE IT REACHES SAID MELTING ZONE OR WITHIN SAID MELTING ZONE,
Claim 2
Dependent Claim
77 words
A PROCESS FOR WORKING UP PARTICULATE POLYOLEFINS IN AN EXTRUDE SAID PARTICULATE POLYOLEFINS HAVING BEEN OBTAINED BY GAS PHASE POLYMERIZATION WITH THE AID OF ZIEGLER/NATTA CATALYSTS AND HAVING A PARTICLE DIAMETER OF LESS THAN 5 MM. SAID PROCESS CONSISTING ESSENTIALLY OF: A. CONTINUOUSLY INTRODUCING SAID PARTICULATE POLYOLEFIN INTO A MELTING ZONE HWEREIN SUFFICIENT HEAT IS APPLIED TO MELT SAID POLYOLEFIN; B. ADDING TO SAID PARTICULATE POLYOLEFIN BEFORE IT REACHES SAID MELTING ZONE OR WITHIN SAID MELTING ZONE,
Claim 3
Dependent Claim
4 words
A C2-C6 ALKENOXIDE, AND
Claim 4
Dependent Claim
4 words
A C2-C6 ALKENOXIDE, AND
Claim 5
Dependent Claim
97 words
WATER, THE AMOUNT OF SAID ALKENOXIDE BEING FROM 3 TO 50 PARTS BY WEIGHT PER 1,000 PARTS OF POLYOLEFIN AND THE AMOUNT OF WATER BEING FROM 0.5 TO 20 PARTS BY WEIGHT PER 1,000 PARTS OF POLYOLEFIN; C. PASSING SAID MOLTEN POLYOLEFIN TO WHICH SAID OXIDE AND SAID WATER HAVE BEEN ADDED TO A DEGASSING ZONE WHEREIN VOLATILES ARE DRIVEN OFF UNDER A VACUUM OF FROM, 0.1 TO 500 MILLIBARS TO SUBSTANTIALLY REDUCE THE HALOGEN CONTENT OF SAID POLYOLEFIN; D. TRANSFERRING THE DEGASSED POLYOLEFIN TO A DISCHARGE ZONE; AND THEREAFTER, E. EXTRUDING AND GRANULATING THE RESULTING POLYOLEFIN.
Claim 6
Dependent Claim
97 words
WATER, THE AMOUNT OF SAID ALKENOXIDE BEING FROM 3 TO 50 PARTS BY WEIGHT PER 1,000 PARTS OF POLYOLEFIN AND THE AMOUNT OF WATER BEING FROM 0.5 TO 20 PARTS BY WEIGHT PER 1,000 PARTS OF POLYOLEFIN; C. PASSING SAID MOLTEN POLYOLEFIN TO WHICH SAID OXIDE AND SAID WATER HAVE BEEN ADDED TO A DEGASSING ZONE WHEREIN VOLATILES ARE DRIVEN OFF UNDER A VACUUM OF FROM, 0.1 TO 500 MILLIBARS TO SUBSTANTIALLY REDUCE THE HALOGEN CONTENT OF SAID POLYOLEFIN; D. TRANSFERRING THE DEGASSED POLYOLEFIN TO A DISCHARGE ZONE; AND THEREAFTER, E. EXTRUDING AND GRANULATING THE RESULTING POLYOLEFIN.
Claim 7
Dependent Claim
97 words
water, the amount of said alkenoxide being from 3 to 50 parts by weight per 1,000 parts of polyolefin and the amount of water being from 0.5 to 20 parts by weight per 1,000 parts of polyolefin; c. passing said molten polyolefin to which said oxide and said water have been added to a degassing zone wherein volatiles are driven off under a vacuum of from 0.1 to 500 millibars to substantially reduce the halogen content of said polyolefin; d. transferring the degassed polyolefin to a discharge zone; and thereafter, e. extruding and granulating the resulting polyolefin.
Claim 8
Dependent Claim
97 words
water, the amount of said alkenoxide being from 3 to 50 parts by weight per 1,000 parts of polyolefin and the amount of water being from 0.5 to 20 parts by weight per 1,000 parts of polyolefin; c. passing said molten polyolefin to which said oxide and said water have been added to a degassing zone wherein volatiles are driven off under a vacuum of from 0.1 to 500 millibars to substantially reduce the halogen content of said polyolefin; d. transferring the degassed polyolefin to a discharge zone; and thereafter, e. extruding and granulating the resulting polyolefin.
Claim 9
Dependent Claim
43 words
The process as set forth in claim 1 wherein up to 10 parts of nitrogen per 1,000 parts of polyolefin, by weight, are additionally added to said polyolefin immediately before it reaches the melting zone or while it is in the melting zone.
Claim 10
Dependent Claim
14 words
The process as set forth in claim 1 wherein said alkeneoxide is propene oxide.
Claim 11
Dependent Claim
15 words
The process as set forth in claim 3 wherein said polyolefin is a propylene polymer.
Claim 12
Dependent Claim
20 words
The process as set forth in claim 11 wherein the temperature in the degassing zone is from 160* to 430*C.
Claim 13
Dependent Claim
49 words
The process as set forth in claim 5 wherein the amount of alkene oxide added to said polyolefin is from 10 to 15 parts by weight per 1,000 parts of polyolefin and the amount of water is from 1 to 5 parts by weight per 1,000 parts of polyolefin.
Claim 14
Dependent Claim
19 words
The process as set forth in claim 5 wherein said particles have a diameter of less than 1 mm.
References Cited (Backward Citations)
US3037011A
Cited
US2974132A
Cited
US3244688A
Cited
US3258456A
Cited
US3436386A
Cited
US3520866A
Cited
US3773743A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-08 | 1979-06-09 | 1979-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-08 | 1983-06-09 | 1983-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-08 | 1987-06-09 | 1987-12-09 | $7700.00 | Window Closed / Lapsed |