Patent US3207737A successfully refreshed from Google Patents.
US3207737A
Expired / Lapsed
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Polymer crystallization method
Assignee: Shell USA Inc
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Filing: 1961-12-18
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Granted: 1965-09-21
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Expires: 1981-12-18
Abstract
No abstract record available.
Inventors
- 👤 Wales Michael
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:17
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/04; C08K5/09; C08K5/098; Y; Y10; Y10S; Y10S260/00; Y10S260/35
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
106 words
THE METHOD OF PRODUCING LOW ASH POLYPROPYLENE ARTICLES OF IMPROVED CLARITY, HARDNESS AND TENSILE STRENGTH WHICH COMPRISES (A) DISPERSING IN (A) POLYPROPYLENE HAVING A VISCOSITY AVERAGE MOLECULAR WEIGHT OF AT LEAST 40,000 AND A CRYSTALLINITY OF AT LEAST 50 PERCENT, AS MEASURED BY XRAY ANALYSIS, AND CONTAINING NO MORE THAN 10 P.P.M., MEASURED AS ASH, OF METAL COMPOUNDS, (B) AN ALUMINUM SALT OF TERT BUTYL BENZOIC ACID USED IN AN AMOUNT CORRESPONDING TO 0.00005 TO 0.005 PERCENT BY WEIGHT OF ALUMINUM, BASED ON THE POLYMER, (B) MELTING THE RESULTING MIXTURE, (C) SHAPING THE MELT INTO A DESIRED SHAPE, AND (D) SOLIDIFYING THE MELT BY COOLING IT.
Claim 2
Independent Claim
106 words
THE METHOD OF PRODUCING LOW ASH POLYPROPYLENE ARTICLES OF IMPROVED CLARITY, HARDNESS AND TENSILE STRENGTH WHICH COMPRISES (A) DISPERSING IN (A) POLYPROPYLENE HAVING A VISCOSITY AVERAGE MOLECULAR WEIGHT OF AT LEAST 40,000 AND A CRYSTALLINITY OF AT LEAST 50 PERCENT, AS MEASURED BY XRAY ANALYSIS, AND CONTAINING NO MORE THAN 10 P.P.M., MEASURED AS ASH, OF METAL COMPOUNDS, (B) AN ALUMINUM SALT OF TERT BUTYL BENZOIC ACID USED IN AN AMOUNT CORRESPONDING TO 0.00005 TO 0.005 PERCENT BY WEIGHT OF ALUMINUM, BASED ON THE POLYMER, (B) MELTING THE RESULTING MIXTURE, (C) SHAPING THE MELT INTO A DESIRED SHAPE, AND (D) SOLIDIFYING THE MELT BY COOLING IT.
References Cited (Backward Citations)
US2984634A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-09-20 | 1969-03-22 | 1969-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-09-20 | 1973-03-22 | 1973-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-09-20 | 1977-03-22 | 1977-09-21 | $7700.00 | Window Closed / Lapsed |