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US4804692A
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Gamma-radiation resistant polycarbonate compositions
Assignee: Bayer Corp
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Filing: 1988-04-28
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Granted: 1989-02-14
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Expires: 2008-04-28
Abstract
Abstract The invention relates to thermoplastic polycarbonate molding compositions which are rendered resistant to gamma-radiation by incorporating therewith about 0.05 to about 10 percent by weight of a stabilizing agent selected from the group consisting of <IMAGE> I YO[(CH2)mO]nY II wherein R is a hydrogen or a halogen atom or a C1-C10 alkyl, a C6-C10 aryl, C1-C22 acyl, C6-C18 alkylaryl or a C4-C10 cycloalkyl radical, m is 1 or 3 to 6, n is an integer of about 20 to 70 and Y is a radical conforming to <IMAGE> wherein R, R' and R'' independently one of the others are selected from C1-C10 alkyl and C6-C12 aryl radicals preferably C1-C4 alkyl radical.
Inventors
- 👤 Charles E. Lundy
- 👤 Winfried G. Paul
- 👤 Sivaram Krishnan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:38
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/54; C08L; C08L69/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
134 words
A polycarbonate molding composition comprising (i) an aromatic polycarbonate resin and (ii) a stabilizing agent selected from the group consisting of ##STR11## and ##STR12## wherein R is a hydrogen or a halogen atom or a C 1 -C 10 alkyl, C 6 -C 10 aryl, C 6 -C 18 arylalkyl or a C 4 -C 10 cycloalkyl radical, Y is a radical conforming to ##STR13## where R, R' and R" independently one of the others are selected from the group consisting of C 1 -C 10 alkyl radicals and C 6 -C 12 aryl radicals, m is 1 or 3 to 6 and n is about 20 to 70, said (ii) being present in sufficient amount to enhance the resistance of said resin to the deterioration of its optical properties upon exposure to gamma-radiation.
Claim 2
Dependent Claim
134 words
A polycarbonate molding composition comprising (i) an aromatic polycarbonate resin and (ii) a stabilizing agent selected from the group consisting of ##STR11## and ##STR12## wherein R is a hydrogen or a halogen atom or a C 1 -C 10 alkyl, C 6 -C 10 aryl, C 6 -C 18 arylalkyl or a C 4 -C 10 cycloalkyl radical, Y is a radical conforming to ##STR13## where R, R' and R" independently one of the others are selected from the group consisting of C 1 -C 10 alkyl radicals and C 6 -C 12 aryl radicals, m is 1 or 3 to 6 and n is about 20 to 70, said (ii) being present in sufficient amount to enhance the resistance of said resin to the deterioration of its optical properties upon exposure to gamma-radiation.
Claim 3
Dependent Claim
22 words
The composition of claim 1 wherein said sufficient amount is about 0.05 to 10 percent relative to the weight of the composition.
Claim 4
Dependent Claim
13 words
The composition of claim 1 wherein said (ii) conforms to ##STR14## wherein n=35.
Claim 5
Dependent Claim
15 words
The composition of claim 1 wherein said polycarbonate is a homopolymer based on bisphenol A.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-02-14 | 1992-08-15 | 1993-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-14 | 1996-08-15 | 1997-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-14 | 2000-08-15 | 2001-02-14 | $7700.00 | Window Closed / Lapsed |