Patent US3755248A successfully refreshed from Google Patents.
US3755248A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polypivalolactone composition with improved thermostability
Assignee: Japan Exlan Co Ltd
•
Filing: 1972-07-20
•
Granted: 1973-08-28
•
Expires: 1992-07-20
Abstract
Abstract A polypivalolactone composition is produced by mixing a polypivalolactone with one or more indole derivatives having a boiling point not less than 260*C. The composition has an improved stability against disintegration or decomposition of the polymer molecules at elevated temperatures.
Inventors
- 👤 Y Shimosaka
- 👤 S Ueda
- 👤 S Nakajima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:42
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/16; C08K5/34; C08K5/3412; C08K5/3415; C08K5/3417
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
24 words
A polypivalolactone composition according to claim 1 wherein the amount of the indole derivative is 0.001 to 10 percent by weight on the polypivalolactone.
Claim 2
Dependent Claim
24 words
A polypivalolactone composition according to claim 2 wherein the amount of the indole derivative is 0.01 to 5 percent by weight on the polypivalolactone.
Claim 3
Dependent Claim
25 words
A polypivalolactone composition according to claim 1 wherein the above mentioned indole derivative has at least hydrocarbon group substituent having 1 to 12 carbon atoms.
Claim 4
Dependent Claim
27 words
A polypivalolactone composition according to claim 4 wherein the hydrocarbon group is selected from the group consisting of alkyl groups, aryl groups, aralkyl groups and alkylaryl groups.
Claim 5
Dependent Claim
37 words
A polypivalolactone composition according to claim 1 wherein the above mentioned indole derivative is a compound selected from the group consisting of 1-butyl-indole, 3-pentylindole, 6-pentylindole, 2-phenylindole, 2,3-diphenylindole, 2,3-diisopropylindole, 2-methyl-3-octylindole, 2-phenyl-3-propylindole, 2,3,5-trimethylindole, 1-methyl-2,3-diphenylindole, 2,3-dimethyl-6-nitroindole, 3-benzyl-5,6-dimethyoxyindole and 1, 2-dimethyl-5-chlorindole.
Claim 6
Dependent Claim
23 words
A polypivalolactone composition according to claim 1 wherein said polypivalolactone is a linear polyester consisting substantially of a recurring unit of the formula
Claim 7
Dependent Claim
16 words
A polypivalolactone composition according to claim 7 wherein said polypivalolactone is a pivalolactone homo- or copolymer.
Claim 8
Dependent Claim
32 words
A polypivalolactone composition according to claim 8 wherein said pivalolactone copolymer is a copolymer consisting of at least 75 mol percent pivalolactone and not more than 25 mol percent of another lactone.
Claim 9
Dependent Claim
18 words
A polypivalolactone composition according to claim 7 wherein said polypivalolactone has an inherent viscosity of at least 1.
References Cited (Backward Citations)
US2476422A
Cited
US2658055A
Cited
US3316207A
Cited
US3352771A
Cited
US3491114A
Cited
US3644279A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |