Patent US2658058A successfully refreshed from Google Patents.
US2658058A
Expired / Lapsed
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Process for making high polymers of alpha-methyl styrene
Assignee: Dow Chemical Co
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Filing: 1952-09-29
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Granted: 1953-11-03
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Expires: 1972-09-29
Abstract
No abstract record available.
Inventors
- 👤 Thomas E Werkema
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:57
CPC Classifications
C; C08; C08F; C08F112/00; C08F112/02; C08F112/04; C08F112/06; C08F112/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
134 words
A PROCESS FOR MAKING A NORMALLY SOLID HOMOPOLYMER OF ALPHA-METHYL STYRENE WHICH COMPRISES POLYMERIZING MONOMERIC ALPHA-METHYL STYRENE IN THE PRESENCE OF AT LEAST ONE ALKALI METAL CATALYST SELECTED FROM THE GROUP CONSISTING OF SODIUM, POTASSIUM AND LITHIUM, ALLOYS OF POTASSIUM AND LITHIUM WITH EACH OTHER, AND MIXTURES AND ALLOYS OF SODIUM WITH AT LEAST ONE OF THE ELEMENTS POTASSIUM AND LITHIUM, IN A REACTION ZONE WHERE THE MIXTURE IS MAINTAINED AT A TEMPERATURE OF FROM 0* TO 30* C. TO EFFECT POLYMERIZATION AND FORM A LIQUID SOLUTION OF POLYMER IN MONOMERIC ALPHA-METHYL STYRENE, WITHDRAWING A PORTION OF THE REACTION LIQUOR FROM SAID REACTION ZONE THROUGH A FILTER WHILE RETAINING THE PRINCIPAL PORTION OF THE NON-CHEMICALLY COMBINED ALKALI METAL CATALYST IN THE RESIDUAL REACTION MIXTURE AND ADDING MONOMERIC ALPHA-METHYL STYRENE TO THE RESIDUAL REACTION MIXTURE.
Claim 2
Dependent Claim
134 words
A PROCESS FOR MAKING A NORMALLY SOLID HOMOPOLYMER OF ALPHA-METHYL STYRENE WHICH COMPRISES POLYMERIZING MONOMERIC ALPHA-METHYL STYRENE IN THE PRESENCE OF AT LEAST ONE ALKALI METAL CATALYST SELECTED FROM THE GROUP CONSISTING OF SODIUM, POTASSIUM AND LITHIUM, ALLOYS OF POTASSIUM AND LITHIUM WITH EACH OTHER, AND MIXTURES AND ALLOYS OF SODIUM WITH AT LEAST ONE OF THE ELEMENTS POTASSIUM AND LITHIUM, IN A REACTION ZONE WHERE THE MIXTURE IS MAINTAINED AT A TEMPERATURE OF FROM 0* TO 30* C. TO EFFECT POLYMERIZATION AND FORM A LIQUID SOLUTION OF POLYMER IN MONOMERIC ALPHA-METHYL STYRENE, WITHDRAWING A PORTION OF THE REACTION LIQUOR FROM SAID REACTION ZONE THROUGH A FILTER WHILE RETAINING THE PRINCIPAL PORTION OF THE NON-CHEMICALLY COMBINED ALKALI METAL CATALYST IN THE RESIDUAL REACTION MIXTURE AND ADDING MONOMERIC ALPHA-METHYL STYRENE TO THE RESIDUAL REACTION MIXTURE.
References Cited (Backward Citations)
US2458378A
Cited
US2621171A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-11-02 | 1957-05-04 | 1957-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-11-02 | 1961-05-04 | 1961-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-11-02 | 1965-05-04 | 1965-11-03 | $7700.00 | Window Closed / Lapsed |