Patent US3096471A successfully refreshed from Google Patents.
Patent EP0256748A2 successfully refreshed from Google Patents.
EP0256748A2
Expired / Lapsed
EP
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Porous highly expanded fluoropolymers and a process for preparing them
Assignee: Baxter International Inc
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Filing: 1987-08-04
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Granted: —
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Expires: 2007-08-04
Abstract
Abstract An interpenetrated polymeric matrix of poly(tetrafluoroethylene) and an elastomer is formed into a composite material which is durable and highly porous. The composite material can be used to produce shaped articles such as films, tubes, rods, and filaments with excellent pliability and elasticity. More particularly, the composite material can be utilized to produce vascular grafts with excellent biological compatibility.
Inventors
- 👤 Roger H. Tu
- 👤 David T. Chen
- 👤 Mark A. Roberts
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 21:35
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; A; A61; A61F; A61F2/00; A61F2/02; A61F2/04; A61F2/06; A61L; A61L27/00; A61L27/14; A61L27/26; A61L27/50; A61L27/507; A61L27/56; B; B29; B29C; B29C48/00; B29C48/022; B29C55/00; B29C55/005; C08J3/00; C08J3/005; C08L; C08L27/00; C08L27/02; C08L27/12; C08L27/18; B29C48/03; B29C48/06; B29C48/07; B29C48/08; B29C48/09; B29K; B29K2027/00; B29K2027/12; B29K2027/18; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
21 words
A composite material comprising unsintered poly(tetrafluoroethylene) polymer and an elastomer which is expanded and oriented and having a porous fibrillated structure.
Claim 2
Dependent Claim
21 words
A composite material comprising unsintered poly(tetrafluoroethylene) polymer and an elastomer which is expanded and oriented and having a porous fibrillated structure.
Claim 3
Dependent Claim
53 words
A composite material in accordance with Claim 1 in which the elastomer is polyvinylidene fluoride co-hexafluoropropylene, poly[tetrafluoroethylene-co-perfluoro(methyl vinyl ether)], poly(tetrafluoroethylene-co-propylene, poly(vinylidene-co-chlorotrifluoroethylene), a silicone, a fluorosilicone, a fluoroalkoxyphosphazene, a segmented copolyester ether, a styrene-butadiene block copolymer, a polyether, an acrylonitrile butadiene copolymer, an isoprene polymer or a mixture of any two or more thereof.
Claim 4
Dependent Claim
14 words
A composite material according to Claim 1 or Claim 2, which exhibits biological compatibility.
Claim 5
Dependent Claim
27 words
A composite material according to any one of the preceding Claims, which has an elastomer content of from 2 to 50% by weight of the composite material.
Claim 6
Dependent Claim
15 words
A composite material according to any one of the preceding Claims, which is expanded biaxially.
Claim 7
Dependent Claim
16 words
A composite material according to any one of Claims 1 to 4, which is expanded uniaxially.
Claim 8
Dependent Claim
26 words
A composite material according to any one of the preceding Claims, which has been stretched and then heated to a temperature ranging from 342°C to 390°C.
Claim 9
Dependent Claim
16 words
A composite material according to any one of the preceding Claims, wherein the elastomer is poly(tetrafluoroethylene-co-propylene).
Claim 10
Dependent Claim
18 words
A composite material according to any one of Claims 1 to 7, wherein the elastomer is a silicone.
Claim 11
Dependent Claim
16 words
A shaped article formed from a composite material according to any one of the preceding Claims.
Claim 12
Dependent Claim
16 words
A shaped article according to Claim 10, which is in the form of a surgical prosthesis.
Claim 13
Dependent Claim
18 words
A shaped article according to Claim 10 or Claim 11, which is in the form of a rod.
Claim 14
Dependent Claim
18 words
A shaped article according to Claim 10 or Claim 11, which is in the form of a tube.
Claim 15
Dependent Claim
18 words
A shaped article according to Claim 10 or Claim 11, which is in the form of a film.
Claim 16
Dependent Claim
19 words
A shaped article according to Claim 10 or Claim 11, which is in the form of a vascular graft.
Claim 17
Dependent Claim
67 words
A process for the production of a porous article, which process comprises expanding an unsintered shaped article according to any one of Claims 10 to 15 comprising highly crystalline poly(tetrafluoroethylene) and an elastomer made by a paste-forming extrusion technique, by stretching said unsintered shaped article and maintaining said shaped article at a temperature between 35°C and the crystalline melting point of the tetrafluoroethylene polymer during said stretching.
Claim 18
Dependent Claim
17 words
A process according to Claim 16, in which the rate of stretch is about 10% per second.
Claim 19
Dependent Claim
17 words
A process according to Claim 16, in which the rate of stretch is about 30% per second.
Claim 20
Dependent Claim
17 words
A process according to Claim 16, in which the rate of stretch is about 100% per second.
Claim 21
Dependent Claim
13 words
A process according to Claim 16, in which said expanding is effected uniaxially.
Claim 22
Dependent Claim
13 words
A process according to Claim 16, in which siad expanding is effected biaxially.
Claim 23
Dependent Claim
29 words
A process according to any one of Claims 16 to 21, in which said expanding produces a porosity of from 40 to 90% in the resultant porous stretched article.
Claim 24
Dependent Claim
29 words
A process according to any one of Claims 16 to 22, wherein the shaped article is heated to a temperature ranging from about 342°C to about 390°C after stretching.
Claim 25
Dependent Claim
21 words
A process according to any one of Claims 16 to 23, wherein the shaped article is submerged in an elastomer dispersion.
Claim 26
Dependent Claim
17 words
A process according to Claim 24, wherein where the elastomer dispersion contains from 1 to 10% elastomer.
Claim 27
Dependent Claim
16 words
A process according to any one of Claims 16 to 25, wherein the elastomer is poly(tetrafluoroethylene-co-propylene).
Claim 28
Dependent Claim
17 words
A process according to any one of Claims 16 to 25, wherein the elastomer is a silicone.
Claim 29
Dependent Claim
32 words
A process according to any one of Claims 16 to 23, wherein the elastomer which is added to the poly(tetrafluoroethylene) to form a paste is in the form of a dry powder.
Claim 30
Dependent Claim
32 words
A process according to any one of Claims 16 to 23, wherein the elastomer which is added to the poly(tetrafluoroethylene) to form a paste is in the form of a liquid dispersion.
Claim 31
Dependent Claim
69 words
A process for the production of a porous article of a polymer of poly(tetrafluoroethylene) which process comprises expanding a shaped article comprising highly crystalline poly(tetrafluoroethylene) made by a paste-forming extrusion technique, by stretching said unsintered shaped article and maintaining said shaped article at a temperature between 35°C and the crystalline melting point of the tetrafluoroethylene polymer during said stretching, wherein the shaped article is submerged in an elastomer dispersion.
Claim 32
Dependent Claim
69 words
A process for the production of a porous article of a polymer of poly(tetrafluoroethylene) which process comprises expanding a shaped article comprising highly crystalline poly(tetrafluoroethylene) made by a paste-forming extrusion technique, by stretching said unsintered shaped article and maintaining said shaped article at a temperature between 35°C and the crystalline melting point of the tetrafluoroethylene polymer during said stretching, wherein the shaped article is submerged in an elastomer dispersion.
Claim 33
Dependent Claim
16 words
A process according to Claim 30 wherein the elastomer dispersion comprises from 1 to 10% elastomer.
Claim 34
Dependent Claim
50 words
A process according to Claim 30 wherein the elastomer is polyvinylidene fluoride co-hexafluoropropylene, poly[tetrafluoroethylene-co-perfluoro (methyl vinyl ether)], poly(tetrafluoroethylene-co-propylene), poly(vinylidene-co-chlorotrifluroethylene), a silicone, a fluorosilicone, a fluoroalkoxyphosphazene, a segmented copolyester ether, a styrene-butadiene block copolymer, a polyether, an acrylonitrile butadiene, an isoprene polymer or a mixture of any two or more thereof.
Claim 35
Dependent Claim
11 words
A process according to Claim 32 wherein the elastomer is poly(tetrafluoroethylene-co-propylene).
Claim 36
Dependent Claim
12 words
A process according to Claim 32 wherein the elastomer is a silicone.
References Cited (Backward Citations)
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