Patent EP0248446A2 successfully refreshed from Google Patents.
EP0248446A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Anisotropic, liquid crystalline, polytetrafluoroethylene and tetrafluoroethylene copolymer aqueous dispersions
Assignee: EIDP Inc
•
Filing: 1987-06-05
•
Granted: —
•
Expires: 2007-06-05
Abstract
Abstract Anisotropic, liquid crystalline, polytetrafluoroethylene (PTFE) and tetrafluoroethylene (TFE) copolymer aqueous dispersions having rod-like particles of PTFE or TFE copolymer, and white PTFE and TFE copolymer fibers prepared directly therefrom.
Inventors
- 👤 Thomas Josef Folda
- 👤 Heinz Hoffmann
- 👤 Paul Smith
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 14:50
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/28; D01F6/32; C; C08; C08F; C08F14/00; C08F14/18; C08F14/26; D01F6/02; D01F6/08; D01F6/12
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
257 words
Process for the production of an anisotropic, liquid crystalline aqueous dispersion by the free radical polymerization of tetrafluoroethylene or a mixture of greater than 50 mol % of tetrafluoroethylene and less than 50 mol % of a comonomer copolymerizable therewith, in an aqueous medium, in a substantially oxygen-free system, the process comprising polymerizing tetrafluoroethylene or a mixture of tetrafluoroethylene and up to 1 mole % of a comonomer copolymerizable therewith, for 1-180 minutes, at 40-150°C, at 20-2000 psig (138-13,800 kPa) of tetrafluoroethylene or tetrafluoroethylene/comonomer, in the presence of 0.0001-0.1 wt./voi.% of free radical initiator and a surfactant of the formula RA wherein: R is 1) Z (̵ CF2 )̵ x (̵ CH 2 CH 2 )̵ y wherein y is 0 or 1; x is 7 to 13; and Z is H, F, CI or Br; or 2) W-CF2CF(W)O t- CF 2 CF(CF 3 )O-)- z CF 2 CF 2 - wherein z is 1 or 2; and W is CI or F; or 3) Z(̵CF 2 )̵ x (̵CH 2 )̵ y wherein y is 0, 1 or 2; x is 8 to 13; and Z is H, F, Cl or Br; and A is -SO 3 M, -COOM or -SOsNR 2 wherein M is Li + , Na + , K + or NH 4 + ; R is -C x H 2x+1 ; and x is 1 to 5. the surfactant concentration being in the range extending from the critical micelle concentration (cmc) to the total solubility of the surfactant in the polymerization medium.
Claim 2
Dependent Claim
257 words
Process for the production of an anisotropic, liquid crystalline aqueous dispersion by the free radical polymerization of tetrafluoroethylene or a mixture of greater than 50 mol % of tetrafluoroethylene and less than 50 mol % of a comonomer copolymerizable therewith, in an aqueous medium, in a substantially oxygen-free system, the process comprising polymerizing tetrafluoroethylene or a mixture of tetrafluoroethylene and up to 1 mole % of a comonomer copolymerizable therewith, for 1-180 minutes, at 40-150°C, at 20-2000 psig (138-13,800 kPa) of tetrafluoroethylene or tetrafluoroethylene/comonomer, in the presence of 0.0001-0.1 wt./voi.% of free radical initiator and a surfactant of the formula RA wherein: R is 1) Z (̵ CF2 )̵ x (̵ CH 2 CH 2 )̵ y wherein y is 0 or 1; x is 7 to 13; and Z is H, F, CI or Br; or 2) W-CF2CF(W)O t- CF 2 CF(CF 3 )O-)- z CF 2 CF 2 - wherein z is 1 or 2; and W is CI or F; or 3) Z(̵CF 2 )̵ x (̵CH 2 )̵ y wherein y is 0, 1 or 2; x is 8 to 13; and Z is H, F, Cl or Br; and A is -SO 3 M, -COOM or -SOsNR 2 wherein M is Li + , Na + , K + or NH 4 + ; R is -C x H 2x+1 ; and x is 1 to 5. the surfactant concentration being in the range extending from the critical micelle concentration (cmc) to the total solubility of the surfactant in the polymerization medium.
Claim 3
Dependent Claim
48 words
Process of Claim 1 wherein the polymerization time is about 1-120 minutes, the temperature is 60-100°C, the pressure of tetrafluoroethylene is 60-600 psig (414-4,140 kPa), the concentration of initiator is 0.005-0.020 wt./vol.%, and the concentration of surfactant is in the range extending from cmc to about 5 wt./vol.%.
Claim 4
Dependent Claim
39 words
Process of Claim 2 wherein the tetrafluoroethylene/comonomer mixture is comprised of greater than 80 mol %, preferably at least 98 mol %, of tetrafluoroethylene and less than 20 mol %, preferably no more than 2 mol %, of comonomer.
Claim 5
Dependent Claim
17 words
Process of Claim 3 wherein the comonomer is vinylidene fluoride, hexafluoropropylene, perfluoropropyl vinyl ether or perfluorobutyl ethylene.
Claim 6
Dependent Claim
17 words
Anisotropic, liquid crystalline aqueous dispersion of polytetrafluoroethylene or tetrafluoroethylene copolymer prepared by the process of Claim 1.
Claim 7
Dependent Claim
69 words
Anisotropic, liquid crystalline aqueous dispersion of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene.
Claim 8
Dependent Claim
69 words
Anisotropic, liquid crystalline aqueous dispersion of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene.
Claim 9
Dependent Claim
160 words
Aqueous dispersion consisting of at least two phases, the uppermost phase being an isotropic aqueous dispersion comprised of rod-like particles of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene, each of the remaining phases being an anisotropic, liquid crystalline aqueous dispersion of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene.
Claim 10
Dependent Claim
160 words
Aqueous dispersion consisting of at least two phases, the uppermost phase being an isotropic aqueous dispersion comprised of rod-like particles of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene, each of the remaining phases being an anisotropic, liquid crystalline aqueous dispersion of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene.
Claim 11
Dependent Claim
102 words
Aqueous dispersion comprised of a mixture of an anisotropic, liquid crystalline aqueous dispersion of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene and up to 95% by weight, based on the combined weights of polymers, of an aqueous polytetrafluoroethylene dispersion substantially comprised of spherical particles of polytetrafluoroethylene.
Claim 12
Dependent Claim
102 words
Aqueous dispersion comprised of a mixture of an anisotropic, liquid crystalline aqueous dispersion of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene and up to 95% by weight, based on the combined weights of polymers, of an aqueous polytetrafluoroethylene dispersion substantially comprised of spherical particles of polytetrafluoroethylene.
Claim 13
Dependent Claim
216 words
Process for the production of a fiber of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene, the process comprising extruding an anisotropic, liquid crystalline aqueous dispersion of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene into a dilute aqueous solution of calcium chloride or magnesium chloride, 1-98% H 2 SO 4 /water, 1-30% HCI/water, ethanol for a dispersion prepared in the presence of a surfactant containing a terminal -S03 group, or aqueous solutions of C 16 H 33 N(CH 3 ) 3 + Br - for a dispersion prepared in the presence of a surfactant containing a terminal -COO- group, and collecting the fiber thus produced.
Claim 14
Dependent Claim
216 words
Process for the production of a fiber of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene, the process comprising extruding an anisotropic, liquid crystalline aqueous dispersion of a polymer selected from polytetrafluoroethylene and a copolymer comprised of greater than 50 mol %, preferably greater than 80 mol % and especially at least 98 mol %, of tetrafluoroethylene repeat units and less than 50 mol %, preferably less than 20 mol % and especially no more than 2 mol %, of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene into a dilute aqueous solution of calcium chloride or magnesium chloride, 1-98% H 2 SO 4 /water, 1-30% HCI/water, ethanol for a dispersion prepared in the presence of a surfactant containing a terminal -S03 group, or aqueous solutions of C 16 H 33 N(CH 3 ) 3 + Br - for a dispersion prepared in the presence of a surfactant containing a terminal -COO- group, and collecting the fiber thus produced.
Claim 15
Dependent Claim
20 words
Process of Claim 9 wherein the concentration of calcium chloride or magnesium chloride is 2-10 wt.%, preferably about 5 wt.%.
Claim 16
Dependent Claim
45 words
White fiber which is produced by a non-sintering process and is comprised of polytetrafluoroethylene or a copolymer comprised of greater than 50 mol % of tetrafluoroethylene repeat units and less than 50 mol % of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene.
Claim 17
Dependent Claim
45 words
White fiber which is produced by a non-sintering process and is comprised of polytetrafluoroethylene or a copolymer comprised of greater than 50 mol % of tetrafluoroethylene repeat units and less than 50 mol % of repeat units of a comonomer which is copolymerizable with tetrafluoroethylene.
Claim 18
Dependent Claim
43 words
Process of Claim 9 wherein the anisotropic, liquid crystalline aqueous dispersion is admixed with up to 95% by weight, preferably 91.5 to 95% by weight, based on the combined weights of polymers, of aqueous polytetrafluoroethylene dispersion substantially comprised of spherical particles of polytetrafluoroethylene.
Claim 19
Dependent Claim
17 words
Process of Claim 12 wherein the dispersion substantially comprised of spherical particles of polytetrafluoroethylene contains a surfactant.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.