US4596855A
Expired / Lapsed
US
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Elastomeric compositions
Assignee: EIDP Inc
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Filing: 1984-12-04
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Granted: 1986-06-24
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Expires: 2004-12-04
Abstract
Abstract An elastomeric composition comprising an elastomer matrix having dispersed therein about 3-30 parts per 100 parts by weight of the elastomer of powdered polytetrafluoroethylene having a number average molecular weight of at least about 250,000 and a surface area of at least 1 m 2 /g which has been treated with about 50-120% of sodium-naphthalene addition compound or another addition compound of an alkali metal required for the alkali metal to react with all the fluorine atoms on the surface of the polytetrafluoroethylene powder. By dispersing such treated polytetrafluoroethylene powder in elastomer matrix, one increases significantly the tear strength of the elastomer, while increasing its modulus only moderately. In this way, the processability of the elastomeric compositions is not adversely affected.
Inventors
- 👤 Charles W. Stewart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:48
CPC Classifications
C; C08; C08L; C08L27/00; C08L27/02; C08L27/12; C08L21/00; C08L27/18
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
105 words
An elastomeric composition comprising an elastomer matrix having dispersed therein about 3-30 parts per 100 parts by weight, based on the elastomer, of powdered polytetrafluoroethylene having a number average molecular weight of at least about 250,000 and a surface area of at least 1 m 2 /g, as determined by the BET technique, which powdered polytetrafluoroethylene has been treated with an amount of an addition compound of an alkali metal of about 50-120% of the theoretical amount required for the alkali metal to react with all the fluorine atoms on the surface of the polytetrafluoroethylene, said composition also containing a curing agent for the elastomer.
Claim 2
Dependent Claim
105 words
An elastomeric composition comprising an elastomer matrix having dispersed therein about 3-30 parts per 100 parts by weight, based on the elastomer, of powdered polytetrafluoroethylene having a number average molecular weight of at least about 250,000 and a surface area of at least 1 m 2 /g, as determined by the BET technique, which powdered polytetrafluoroethylene has been treated with an amount of an addition compound of an alkali metal of about 50-120% of the theoretical amount required for the alkali metal to react with all the fluorine atoms on the surface of the polytetrafluoroethylene, said composition also containing a curing agent for the elastomer.
Claim 3
Dependent Claim
40 words
An elastomeric composition of claim 1 wherein the amount of the alkali metal addition compound is at most about the theoretical amount required for the alkali metal to react with all the fluorine atoms on the surface of the polytetrafluoroethylene.
Claim 4
Dependent Claim
25 words
An elastomeric composition of claim 1 wherein the alkali metal addition compound is an addition compound with an aromatic hydrocarbon,, ammonia, or an organic amine.
Claim 5
Dependent Claim
18 words
An elastomeric composition of claim 3 wherein the addition compound is an addition compound with an aromatic hydrocarbon.
Claim 6
Dependent Claim
14 words
An elastomeric composition of claim 1 wherein the aromatic hydrocarbon is naphthalene or anthracene.
Claim 7
Dependent Claim
12 words
An elastomeric composition of claim 5 wherein the alkali metal is sodium.
Claim 8
Dependent Claim
23 words
An elastomeric composition of claim 1 wherein the alkali metal addition compound is an addition compound of sodium with a polynuclear aromatic hydrocarbon.
Claim 9
Dependent Claim
12 words
An elastomeric composition of claim 1 wherein the elastomer is a fluoroelastomer.
Claim 10
Dependent Claim
114 words
An elastomeric composition comprising an elastomer matrix having dispersed therein about 3-30 parts per 100 parts by weight, based on the elastomer, of powdered polytetrafluoroethylene having a number average molecular weight of at least about 250,000 and a surface area of at least 1 m 2 /g, as determined by the BET technique, which has been treated first with an amount of an addition compound of an alkali metal above the theoretical amount required for the alkali metal to react with all the fluorine atoms on the surface of the polytetrafluoroethylene powder and then with a hypochlorite solution to remove excess surface reaction products, said composition also containing a curing agent for the elastomer.
Claim 11
Dependent Claim
114 words
An elastomeric composition comprising an elastomer matrix having dispersed therein about 3-30 parts per 100 parts by weight, based on the elastomer, of powdered polytetrafluoroethylene having a number average molecular weight of at least about 250,000 and a surface area of at least 1 m 2 /g, as determined by the BET technique, which has been treated first with an amount of an addition compound of an alkali metal above the theoretical amount required for the alkali metal to react with all the fluorine atoms on the surface of the polytetrafluoroethylene powder and then with a hypochlorite solution to remove excess surface reaction products, said composition also containing a curing agent for the elastomer.
Claim 12
Dependent Claim
25 words
An elastomeric composition of claim 9 wherein the alkali metal addition compound is an addition compound with an aromatic hydrocarbon, ammonia, or an organic amine.
Claim 13
Dependent Claim
18 words
An elastomeric composition of claim 10 wherein the addition compound is an addition compound with an aromatic hydrocarbon.
Claim 14
Dependent Claim
14 words
An elastomeric composition of claim 11 wherein the aromatic hydrocarbon is naphthalene or anthracene.
Claim 15
Dependent Claim
12 words
An elastomeric composition of claim 12 wherein the alkali metal is sodium.
Claim 16
Dependent Claim
22 words
An elastomeric composition of claim 9 wherein the alkali metal addition compound is an addition compound of sodium with a polynuclear hydrocarbon.
Claim 17
Dependent Claim
13 words
An elastomeric composition of claim 9 wherein the elastomer matrix is a fluoroelastomer.
Claim 18
Dependent Claim
14 words
An elastomeric composition of claim 15 wherein the fluoroelastomer is a vinylidene fluoride/hexafluoropropene copolymer.
Claim 19
Dependent Claim
14 words
A composition obtained by curing the elastomer matrix of a composition of claim 1.
Claim 20
Dependent Claim
14 words
A composition obtained by curing the elastomer matrix of a composition of claim 8.
Claim 21
Dependent Claim
14 words
A composition obtained by curing the elastomer matrix of a composition of claim 9.
Claim 22
Dependent Claim
14 words
A composition obtained by curing the elastomer matrix of a composition of claim 15.
Claim 23
Dependent Claim
14 words
A composition obtained by curing the elastomer matrix of a composition of claim 16.
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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) | 1989-06-23 | 1989-12-23 | 1990-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-23 | 1993-12-23 | 1994-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-23 | 1997-12-23 | 1998-06-24 | $7700.00 | Window Closed / Lapsed |