Patent US2991269A successfully refreshed from Google Patents.
US2991269A
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Process for preparing block copolymers by degrading a preformed polymer in the presence of dissimilar monomer
Assignee: Shell USA Inc
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Filing: 1956-02-21
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Granted: 1961-07-04
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Expires: 1976-02-21
Abstract
No abstract record available.
Inventors
- 👤 Nozaki Kenzie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:18
CPC Classifications
C; C08; C08F; C08F291/00; Y; Y10; Y10S; Y10S260/00; Y10S260/43; Y10S516/00; Y10S516/01; Y10S525/00; Y10S525/938; Y10S526/00; Y10S526/914
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
81 words
A PROCESS FOR PRODUCING A NEW TYPE COPOLYMER WHICH COMPRISES ADDING A PREFORMED LINEAR POLYMER WHICH IS FREE OF ALIPHATIC-CARBON-TO-CARBON UNSATURATION AND HAS A MOLECULAR WEIGHT OF AT LEAST 50,000 TO A LIQUID REACTION MEDIUM CONTAINING AT LEAST ONE MONOMER POSSESSING A CH2=C<GROUP, AT LEAST ONE OF THE SAID MONOMERS BEING DISSIMILAR TO A MONOMER UNIT CONTAINED IN THE SAID LINEAR POLYMER, AND SUBJECTING THE RESULTING MIXTURE IN AN INERT ATMOSPHERE TO MECHANICAL AGITATION TO BREAK THE SAID PREFORMED LINEAR POLYMER.
Claim 2
Dependent Claim
81 words
A PROCESS FOR PRODUCING A NEW TYPE COPOLYMER WHICH COMPRISES ADDING A PREFORMED LINEAR POLYMER WHICH IS FREE OF ALIPHATIC-CARBON-TO-CARBON UNSATURATION AND HAS A MOLECULAR WEIGHT OF AT LEAST 50,000 TO A LIQUID REACTION MEDIUM CONTAINING AT LEAST ONE MONOMER POSSESSING A CH2=C<GROUP, AT LEAST ONE OF THE SAID MONOMERS BEING DISSIMILAR TO A MONOMER UNIT CONTAINED IN THE SAID LINEAR POLYMER, AND SUBJECTING THE RESULTING MIXTURE IN AN INERT ATMOSPHERE TO MECHANICAL AGITATION TO BREAK THE SAID PREFORMED LINEAR POLYMER.
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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) | 1964-07-03 | 1965-01-02 | 1965-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-07-03 | 1969-01-02 | 1969-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-07-03 | 1973-01-02 | 1973-07-04 | $7700.00 | Window Closed / Lapsed |