US3032530A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing polysiloxane gums
Assignee: Dow Silicones Corp
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Filing: 1958-10-13
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Granted: 1962-05-01
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Expires: 1978-10-13
Abstract
No abstract record available.
Inventors
- 👤 Richard A Falk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:44
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/04; C08G77/06; C08G77/08; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/61; C08G18/70; C08G18/71; C08K; C08K5/00; C08K5/16; C08K5/29
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
137 words
A METHOD OF PREPARING A HIGH POLYMER DIORGANOPOLYSILOXANE WHICH COMPRISES HEATING IN THE ABSENCE OF ANY OTHER POLYMERIZATION CATALYST A MIXTURE OF (1) AN ORGANOPOLYSILOXANE HAVING AN AVERAGE DEGREE OF POLYMERIZATION OF AT LEAST 150 AND CONTAINING AT LEAST TWO SILICON-BONDED HYDROXYL GROUPS PER MOLECULE, SAID ORGANOPOLYSILOXANE HAVING PER SILICON ATOM AT AVERAGE OF FROM 1.99 TO 2.0 ORGANIC RADICALS ATTACHED TO THE SILICON BY SILICON-CARBON LINKAGES, OF WHICH ORGANIC RADICALS AT LEAST 40 PERCENT ARE METHYL RADICALS AND THE REMAINDER CONTAIN NO ACTIVE HYDROGEN CAPABLE OF REACTING WITH METHYLMAGNESIUM CHLORIDE TO GIVE METHANE AND (2) AN ORGANIC ISOCYANATE AND HAVING ONLY ON ISOCYANATE GROUP PER MOLECULE, SAID ISOCYANATE GROUP BEING ATTACHED TO A CARBON ATOM, WHEREBY A GUM HAVING A DEGREE OF POLYMERIZATION GREATER THAN THAT OF (1) BUT EQUAL TO AT LEAST 1500 IS OBTAINED.
Claim 2
Independent Claim
137 words
A METHOD OF PREPARING A HIGH POLYMER DIORGANOPOLYSILOXANE WHICH COMPRISES HEATING IN THE ABSENCE OF ANY OTHER POLYMERIZATION CATALYST A MIXTURE OF (1) AN ORGANOPOLYSILOXANE HAVING AN AVERAGE DEGREE OF POLYMERIZATION OF AT LEAST 150 AND CONTAINING AT LEAST TWO SILICON-BONDED HYDROXYL GROUPS PER MOLECULE, SAID ORGANOPOLYSILOXANE HAVING PER SILICON ATOM AT AVERAGE OF FROM 1.99 TO 2.0 ORGANIC RADICALS ATTACHED TO THE SILICON BY SILICON-CARBON LINKAGES, OF WHICH ORGANIC RADICALS AT LEAST 40 PERCENT ARE METHYL RADICALS AND THE REMAINDER CONTAIN NO ACTIVE HYDROGEN CAPABLE OF REACTING WITH METHYLMAGNESIUM CHLORIDE TO GIVE METHANE AND (2) AN ORGANIC ISOCYANATE AND HAVING ONLY ON ISOCYANATE GROUP PER MOLECULE, SAID ISOCYANATE GROUP BEING ATTACHED TO A CARBON ATOM, WHEREBY A GUM HAVING A DEGREE OF POLYMERIZATION GREATER THAN THAT OF (1) BUT EQUAL TO AT LEAST 1500 IS OBTAINED.
References Cited (Backward Citations)
US2780611A
Cited
US2931786A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-04-30 | 1965-10-30 | 1966-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-04-30 | 1969-10-30 | 1970-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-04-30 | 1973-10-30 | 1974-05-01 | $7700.00 | Window Closed / Lapsed |