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US4563259A
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Polyolefin compositions and articles sterilizable by irradiation
Assignee: BASF SE
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Filing: 1982-09-28
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Granted: 1986-01-07
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Expires: 2002-09-28
Abstract
Abstract Polyolefin compositions and articles, especially articles of medical ware, such as polypropylene hypodermic syringes, are made more resistant to the embrittlement which accompanies sterilization by high energy (e.g. gamma) irradiation by the addition to a polyolefin of narrow molecular weight distribution of a heterocyclic hindered amine and, optionally, a liquid modifier.
Inventors
- 👤 Martin G. Rayner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:43
CPC Classifications
A; A61; A61L; A61L2/00; A61L2/02; A61L2/08; C; C08; C08K; C08K5/00; C08K5/16; C08K5/34; C08K5/3412; C08K5/3432; C08K5/3435
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
146 words
A polyolefin composition comprising a substantially crystalline polymer of an aliphatic mono-alpha-olefin the molecule of which contains from 2 to 6 carbon atoms wherein the molecular weight distribution ratio of the polymer (Mw/Mn) does not exceed 7.0 and from 0.01 to 2.0% by weight of a polymer of a hindered amine or its salt, N-oxide, N-hydroxide or N-nitroxide wherein the amino nitrogen is contained in a carbon-nitrogen-carbon chain which forms part of a non-aromatic heterocyclic ring and wherein each of the two carbon atoms of the chain is bonded to two lower alkyl groups which may be the same or different, each lower alkyl group containing from 1 to 12 carbon atoms, or to an alicyclic group containing from 4 to 9 carbon atoms, which groups sterically hinder the amine, and wherein the composition is sterilized by exposure to a sterilizing amount of high energy irradiation.
Claim 2
Dependent Claim
146 words
A polyolefin composition comprising a substantially crystalline polymer of an aliphatic mono-alpha-olefin the molecule of which contains from 2 to 6 carbon atoms wherein the molecular weight distribution ratio of the polymer (Mw/Mn) does not exceed 7.0 and from 0.01 to 2.0% by weight of a polymer of a hindered amine or its salt, N-oxide, N-hydroxide or N-nitroxide wherein the amino nitrogen is contained in a carbon-nitrogen-carbon chain which forms part of a non-aromatic heterocyclic ring and wherein each of the two carbon atoms of the chain is bonded to two lower alkyl groups which may be the same or different, each lower alkyl group containing from 1 to 12 carbon atoms, or to an alicyclic group containing from 4 to 9 carbon atoms, which groups sterically hinder the amine, and wherein the composition is sterilized by exposure to a sterilizing amount of high energy irradiation.
Claim 3
Dependent Claim
44 words
A polyolefin composition according to claim 1 wherein the composition additionally comprises a modifying amount of a modifier, said modifier being a low molecular weight non-crystalline material which is miscible and compatible with the polymer and which increases the free volume of the polymer.
Claim 4
Dependent Claim
15 words
A composition according to claim 1 wherein the hindered amine comprises a 6-membered heterocyclic ring.
Claim 5
Dependent Claim
29 words
A composition according to claim 1 wherein the hindered amine is carried by a carrier selected from the group consisting of a dicarboxylate, a triazine ring and a diketone.
Claim 6
Dependent Claim
30 words
A composition according to claim 2 wherein the modifier is selected from the group consisting of hydrocarbon oils, halogenated hydrocarbon oils, phthalic esters, polymer greases, vegetable oils and silicone oils.
Claim 7
Dependent Claim
10 words
An article formed from a composition according to claim 1.
Claim 8
Dependent Claim
16 words
An article according to claim 6 wherein the article is a component for a hypodermic syringe.
Claim 9
Dependent Claim
15 words
An article according to claim 6 wherein the article is an article of medical ware.
Claim 10
Dependent Claim
26 words
An article according to claim 6 wherein the article is an article of medical ware and wherein the high energy irradiation is high energy gamma irradiation.
Claim 11
Independent Claim
152 words
A method of sterilizing an article by forming an article from a composition comprising (a) a substantially crystalline polymer of an aliphatic mono-alpha-olefin the molecule of which contains from 2 to 6 carbon atoms, the molecular weight distribution ratio of the polymer (Mw/Mn) not exceeding 7.0, and (b) from 0.01 to 2.0% by weight of the polymer of a hindered amine or its salt, N-oxide, N-hydroxide or N-nitroxide wherein the amino nitrogen is contained in a carbon-nitrogen-carbon chain which forms part of a non-aromatic heterocyclic ring and wherein each of the two carbon atoms of the chain is bonded to two lower alkyl groups which may be the same or different, each lower alkyl group containing from 1 to 12 carbon atoms, or to an alicyclic group containing from 4 to 9 carbon atoms, which groups sterically hinder the amine, and exposing the article to a sterilizing amount of high energy irradiation.
Claim 12
Independent Claim
152 words
A method of sterilizing an article by forming an article from a composition comprising (a) a substantially crystalline polymer of an aliphatic mono-alpha-olefin the molecule of which contains from 2 to 6 carbon atoms, the molecular weight distribution ratio of the polymer (Mw/Mn) not exceeding 7.0, and (b) from 0.01 to 2.0% by weight of the polymer of a hindered amine or its salt, N-oxide, N-hydroxide or N-nitroxide wherein the amino nitrogen is contained in a carbon-nitrogen-carbon chain which forms part of a non-aromatic heterocyclic ring and wherein each of the two carbon atoms of the chain is bonded to two lower alkyl groups which may be the same or different, each lower alkyl group containing from 1 to 12 carbon atoms, or to an alicyclic group containing from 4 to 9 carbon atoms, which groups sterically hinder the amine, and exposing the article to a sterilizing amount of high energy irradiation.
Claim 13
Dependent Claim
39 words
A method according to claim 10 wherein the composition additionally comprises a modifier, said modifier being a low molecular weight non-crystalline material which is miscible and compatible with the polymer and which increases the free volume of the polymer.
Claim 14
Dependent Claim
15 words
A method as in claim 10 wherein the article is an article of medical ware.
Claim 15
Dependent Claim
26 words
The method as in claim 10 wherein the hindered amine or salt is present in an amount between 0.08 to 0.3% by weight of the polymer.
Claim 16
Dependent Claim
18 words
The method as in claim 12 or 13 wherein the high energy irradiation is high energy gamma irradiation.
Claim 17
Dependent Claim
10 words
An article sterilized according to the method of claim 10.
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) | 1989-01-06 | 1989-07-08 | 1990-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-06 | 1993-07-08 | 1994-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-06 | 1997-07-08 | 1998-01-07 | $7700.00 | Window Closed / Lapsed |