US3248377A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Styrene polymerization process
Assignee: Standard Oil Co
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Filing: 1960-12-22
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Granted: 1966-04-26
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Expires: 1980-12-22
Abstract
No abstract record available.
Inventors
- 👤 Vernon W Arnold
- 👤 Gert H Weisemann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:26
CPC Classifications
C; C08; C08F; C08F12/00; C08F12/02; C08F12/04; C08F12/06; C08F12/08; Y; Y10; Y10S; Y10S526/00; Y10S526/912
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
145 words
IN A PROCESS FOR THE POLYMERIZATION OF STYRENE IN SOLUTION IN AN INERT HYDROCARBON REACTION MEDIUM WHEREIN THE POLYMERIZATION IS EFFECTED BY MEANS OF AN ALKALI METAL CATALYST AND DIHYDRIC ALCOHOL DIALKYLETHER PROMOTER, THE IMPROVED METHOD OF OPERATION WHICH COMPRISES THE STEPS OF (1) POLYMERIZING A REFLUXING SOLUTION OF ABOUT 10 TO ABOUT 15 WEIGHT PERCENT STYRENE AT A TEMPERATURE BETWEEN 50*C. AND ABOUT 100*C. AND SUB-ATMOSPHERIC PRESSURE (2) ADDING MONOMERIC STYRENE TO THE POLYMER SOLUTION FORMED IN STEP (1) IN AN AMOUNT SUFFICIENT TO PROVIDE A STYRENE CONCENTRATION OF AT LEAST 10 WEIGHT PERCENT AND NOT MORE THAN 15 WEIGHT PERCENT AND EFFECTING POLYMERIZATION OF SAID ADDED STYRENE IN THE PRESENCE OF A FURTHER QUANTITY OF SAID CATALYST AND PROMOTER (3) SEPARATING POLYSTYRENE FROM SAID INERT HYDROCARBON REACTION MEDIUM HAVING AN INTRINSIC VISCOSITY (MEASURED IN BENZENE AT 30*C.) FROM ABOUT 0.7 TO ABOUT 1.4.
Claim 2
Dependent Claim
145 words
IN A PROCESS FOR THE POLYMERIZATION OF STYRENE IN SOLUTION IN AN INERT HYDROCARBON REACTION MEDIUM WHEREIN THE POLYMERIZATION IS EFFECTED BY MEANS OF AN ALKALI METAL CATALYST AND DIHYDRIC ALCOHOL DIALKYLETHER PROMOTER, THE IMPROVED METHOD OF OPERATION WHICH COMPRISES THE STEPS OF (1) POLYMERIZING A REFLUXING SOLUTION OF ABOUT 10 TO ABOUT 15 WEIGHT PERCENT STYRENE AT A TEMPERATURE BETWEEN 50*C. AND ABOUT 100*C. AND SUB-ATMOSPHERIC PRESSURE (2) ADDING MONOMERIC STYRENE TO THE POLYMER SOLUTION FORMED IN STEP (1) IN AN AMOUNT SUFFICIENT TO PROVIDE A STYRENE CONCENTRATION OF AT LEAST 10 WEIGHT PERCENT AND NOT MORE THAN 15 WEIGHT PERCENT AND EFFECTING POLYMERIZATION OF SAID ADDED STYRENE IN THE PRESENCE OF A FURTHER QUANTITY OF SAID CATALYST AND PROMOTER (3) SEPARATING POLYSTYRENE FROM SAID INERT HYDROCARBON REACTION MEDIUM HAVING AN INTRINSIC VISCOSITY (MEASURED IN BENZENE AT 30*C.) FROM ABOUT 0.7 TO ABOUT 1.4.
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) | 1969-04-25 | 1969-10-25 | 1970-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-04-25 | 1973-10-25 | 1974-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-04-25 | 1977-10-25 | 1978-04-26 | $7700.00 | Window Closed / Lapsed |