Patent US1270129A successfully refreshed from Google Patents.
Patent US2908662A successfully refreshed from Google Patents.
US2908662A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Graft copolymers prepared from unsaturated polyvinyl chloride and acrylic esters and method of making same
Assignee: Shawinigan Chemicals Ltd
•
Filing: 1957-01-22
•
Granted: 1959-10-13
•
Expires: 1977-01-22
Abstract
No abstract record available.
Inventors
- 👤 Richard W Rees
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:09
CPC Classifications
C; C08; C08F; C08F259/00; C08F259/02; C08F259/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
137 words
A PROCESS FOR TE PREPARATION OF A GRAFT COPOLYMER DERIVED FROM A SATURATED POLYMER OF THE GROUP CONSISTING OF POLYVINYL CHLORIDE AND COPOLYMERS OF VINYL CHLORIDE AND VINYL ACETATE WHEREIN THE VINYL ACETATE DOES NOT EXCEED 20% BY WEIGHT OF THE TOTAL COPOLYMER, COMPRISING REACTING, UNDER POLYMERIZING CONDITIONS IN THE PRESENCE OF A POLYMERIZATION CATALYST COMPRISING AN ORGANIC PEROXYGEN COMPOUND, (1) A LOWER ALKYL ESTER OF ACRYLIC ACID, AND (2) AN UNSATURATED POLYMER PREPARED BY (A) REACTING A SOLUTION OF SAID SATURATED POLYMER, IN AN INERT SOLVENT OF THE GROUP CONSISTING OF DIOXIDE AND DIMETHYLFORMAMIDE, WITH AMMONIA AT A TEMPERATURE BETWEEN 20* C. AND 150*C. AND A PRESSURE BETWEEN 40 P.S.I.G. AND 100 P.S.I.G. WHEREBY HYDROGEN CHLORIDE IS REMOVED FROM THE POLYMER AND AN UNSATURATED POLYMER IS PRODUCED, AND (B) RECOVERING THE UNSATURATED POLYMER FROM THE SOLUTION.
Claim 2
Dependent Claim
137 words
A PROCESS FOR TE PREPARATION OF A GRAFT COPOLYMER DERIVED FROM A SATURATED POLYMER OF THE GROUP CONSISTING OF POLYVINYL CHLORIDE AND COPOLYMERS OF VINYL CHLORIDE AND VINYL ACETATE WHEREIN THE VINYL ACETATE DOES NOT EXCEED 20% BY WEIGHT OF THE TOTAL COPOLYMER, COMPRISING REACTING, UNDER POLYMERIZING CONDITIONS IN THE PRESENCE OF A POLYMERIZATION CATALYST COMPRISING AN ORGANIC PEROXYGEN COMPOUND, (1) A LOWER ALKYL ESTER OF ACRYLIC ACID, AND (2) AN UNSATURATED POLYMER PREPARED BY (A) REACTING A SOLUTION OF SAID SATURATED POLYMER, IN AN INERT SOLVENT OF THE GROUP CONSISTING OF DIOXIDE AND DIMETHYLFORMAMIDE, WITH AMMONIA AT A TEMPERATURE BETWEEN 20* C. AND 150*C. AND A PRESSURE BETWEEN 40 P.S.I.G. AND 100 P.S.I.G. WHEREBY HYDROGEN CHLORIDE IS REMOVED FROM THE POLYMER AND AN UNSATURATED POLYMER IS PRODUCED, AND (B) RECOVERING THE UNSATURATED POLYMER FROM THE SOLUTION.
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) | 1962-10-12 | 1963-04-13 | 1963-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-10-12 | 1967-04-13 | 1967-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-10-12 | 1971-04-13 | 1971-10-13 | $7700.00 | Window Closed / Lapsed |