Patent US4873271A successfully refreshed from Google Patents.
US4873271A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gamma radiation rsistant polycarbonate compositions
Assignee: Bayer Corp
•
Filing: 1989-04-25
•
Granted: 1989-10-10
•
Expires: 2009-04-25
Abstract
Abstract The invention relates to thermoplastic polycarbonate molding compositions which are rendered improved resistance to gamma-radiation by the incorporation therewith of about 0.05 to about 5.0 percent by weight of an ester of poly(alkylene)oxide conforming to ##STR1## wherein R is a C 1 -C 20 alkyl, aryl or alkylaryl, Y denotes a hydrogen atom or a C 1 -C 6 alkyl radical, and X is about 1 to 40, preferably 5 to 30. The compositions of the invention exhibit excellent resistance to yellowness and formation of haze which commonly characterize gamma irradiated articles molded from polycarbonate.
Inventors
- 👤 Charles E. Lundy
- 👤 Sivaram Krishnan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:56
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/04; C08K5/10; C08K5/101; C08K5/103
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
54 words
A thermoplastic molding composition comprising (i) an aromatic polycarbonate resin and about 0.05 to 5.0% of (ii) a stabilizing agent conforming to ##STR6## wherein R denotes a C 1 -C 20 alkyl, aryl or alkylaryl radical, Y denotes a C 1 -C 6 alkyl or a hydrogen atom and X is 1 to 40.
Claim 2
Dependent Claim
54 words
A thermoplastic molding composition comprising (i) an aromatic polycarbonate resin and about 0.05 to 5.0% of (ii) a stabilizing agent conforming to ##STR6## wherein R denotes a C 1 -C 20 alkyl, aryl or alkylaryl radical, Y denotes a C 1 -C 6 alkyl or a hydrogen atom and X is 1 to 40.
Claim 3
Dependent Claim
26 words
The composition of claim 1 wherein said (ii) is present in an amount of about 0.1 to 3.0 percent relative to the weight of the composition.
Claim 4
Dependent Claim
13 words
The composition of claim 1 wherein said R is an acetic acid derivative.
Claim 5
Dependent Claim
13 words
The composition of claim 1 wherein said R is a stearic acid derivative.
Claim 6
Dependent Claim
15 words
The composition of claim 1 wherein said polycarbonate is a homopolymer based on bisphenol A.
Claim 7
Dependent Claim
12 words
The composition of claim 1 wherein said Y is a hydrogen atom.
Claim 8
Dependent Claim
12 words
The composition of claim 1 wherein said X is 5 to 30.
References Cited (Backward Citations)
US4431497A
Cited
US4460445A
Cited
US4451641A
Cited
EP0152012A2
Cited
US4624972A
Cited
US4657949A
Cited
US4804692A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-09 | 1993-04-10 | 1993-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-09 | 1997-04-10 | 1997-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-09 | 2001-04-10 | 2001-10-10 | $7700.00 | Window Closed / Lapsed |