Patent US937550A successfully refreshed from Google Patents.
Patent US2981720A successfully refreshed from Google Patents.
US2981720A
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US
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Chlorination and sulfochlorination of low-pressure polyethylene
Assignee: Hoechst AG
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Filing: 1956-07-17
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Granted: 1961-04-25
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Expires: 1976-07-17
Abstract
No abstract record available.
Inventors
- 👤 Herzberg Horst
- 👤 Orthner Ludwig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 06:05
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/34; C08F8/18; C08F8/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
163 words
A NOVEL PROCESS OF CHLORINATING POLYETHYLENE HAVING A MOLECULAR WEIGHT ABOVE 50,000, A MELTING POINT OF AT LEAST 130*C., A CRYSTALLINITY OF AT LEAST 80%, CONTAINING LESS THAN THREE METHYL GROUPS PER 100 METHYLENE GROUPS, AND BEING INSOLUBLE IN CHLORINATED HYDROCARBONS AT TEMPERATURES BELOW 100*C., SAID POLYETHYLENE BEING PREPARED BY POLYMERIZING ETHYLENE IN THE PRESENCE OF A CATALYTIC AMOUNT OF A HEAVY METAL COMPOUND OF SUBGROUPS IV-VI OF THE PERIODIC TABLE AND A METALLO-ORGANIC COMPOUND, SAID NOVEL PROCESS COMPRISING THE STEPS OF FIRST CONTACTING SAID POLYETHYLENE WITH CHLORINE UNDER ELEVATED PRESSURE AT A TEMPERATURE OF 100-160*C. IN A CHLORINATED HYDROCARBON HAVING A BOILING POINT BELOW 100*C. TO FORM A HOMOGENEOUS SOLUTION OF PARTIALLY CHLORINATED POLYETHYLENE, THE LATTER HAVING A CHLORINE CONTENT OF 5-10% BY WEIGHT, COOLING SAID SOLUTION TO A TEMPERATURE WITHIN THE RANGE OF 20-80*C., AND THEN INTRODUCING ADDITIONAL CHLORINE INTO SAID SOLUTION UNDER ATMOSPHERIC PRESSURE WHILE MAINTAINING THE TEMPERATURE WITHIN SAID RANGE OF 20-80*C. UNTIL CHLORINATION OF THE POLYETHYLENE IS COMPLETED.
Claim 2
Dependent Claim
163 words
A NOVEL PROCESS OF CHLORINATING POLYETHYLENE HAVING A MOLECULAR WEIGHT ABOVE 50,000, A MELTING POINT OF AT LEAST 130*C., A CRYSTALLINITY OF AT LEAST 80%, CONTAINING LESS THAN THREE METHYL GROUPS PER 100 METHYLENE GROUPS, AND BEING INSOLUBLE IN CHLORINATED HYDROCARBONS AT TEMPERATURES BELOW 100*C., SAID POLYETHYLENE BEING PREPARED BY POLYMERIZING ETHYLENE IN THE PRESENCE OF A CATALYTIC AMOUNT OF A HEAVY METAL COMPOUND OF SUBGROUPS IV-VI OF THE PERIODIC TABLE AND A METALLO-ORGANIC COMPOUND, SAID NOVEL PROCESS COMPRISING THE STEPS OF FIRST CONTACTING SAID POLYETHYLENE WITH CHLORINE UNDER ELEVATED PRESSURE AT A TEMPERATURE OF 100-160*C. IN A CHLORINATED HYDROCARBON HAVING A BOILING POINT BELOW 100*C. TO FORM A HOMOGENEOUS SOLUTION OF PARTIALLY CHLORINATED POLYETHYLENE, THE LATTER HAVING A CHLORINE CONTENT OF 5-10% BY WEIGHT, COOLING SAID SOLUTION TO A TEMPERATURE WITHIN THE RANGE OF 20-80*C., AND THEN INTRODUCING ADDITIONAL CHLORINE INTO SAID SOLUTION UNDER ATMOSPHERIC PRESSURE WHILE MAINTAINING THE TEMPERATURE WITHIN SAID RANGE OF 20-80*C. UNTIL CHLORINATION OF THE POLYETHYLENE IS COMPLETED.
References Cited (Backward Citations)
US2398803A
Cited
US2692257A
Cited
US2816883A
Cited
US2710854A
Cited
BE533362A
Cited
US2920064A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-24 | 1964-10-24 | 1965-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-24 | 1968-10-24 | 1969-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-24 | 1972-10-24 | 1973-04-25 | $7700.00 | Window Closed / Lapsed |