Thermoplastic fluoroelastomer composition

Claim 2

A thermoplastic fluoroelastomer composition comprising a thermoplastic fluoroelastomer, a liquid fluoroelastomer and optionally a cross-linking agent.

Claim 3

A composition according to claim 1, wherein the thermoplastic fluoroelastomer comprises a polymeric chain comprising at least one elastomeric polymer segment and at least one non-elastomeric polymer segment, at least one of these segments being a fluorine-containing polymer segment.

Claim 4

A composition according to claim 2, wherein the weight ratio of the elastomeric polymer segment and the non-elastomeric polymer segment is from 40 : 60 to 95 : 5.

Claim 5

A composition according to claim 1, wherein the thermoplastic fluoroelastomer comprises a polymeric chain comprising two or three polymer segments, at least one iodine atom liberated from an iodinated compound and bonded to a terminal carbon atom of the polymeric chain and a fragment of the iodinated compound excluding said liberated iodine atom therefrom; one polymer segment (when the polymeric chain comprises two polymer segments) or one or two polymer segments (when the polymeric chain comprises three polymer segments) being elastomeric polymer segment(s) having a molecular weight of from 30,000 to 1,200,000 selected from the group consisting of (1) a vinylidene fluoride/hexafluoropropylene or pentafluoropropylene/tetrafluoroethylene polymer in a molar ratio of 45-90 : 5-50 : 0-35 and (2) a perfluoro(C 1 -C 3 -alkyl vinyl ether) (including those having plural ether linkages)/tetrafluoroethylene/vinylidene fluoride polymer in a molar ratio of 15-75 : 0-85 : 0-85, other polymer segment(s) being a non-elastomeric polymer having a molecular weight of from 3,000 to 400,000 selected from the group consisting of (3) a vinylidene fluoride/tetrafluoroethylene polymer in a molar ratio of 0 : 100 to 100 : 0 and (4) a ethylene/tetrafluoroethylene/hexa- fluoropropylene, 3,3,3-trifluoropropylene-1, 2 - trifluoromethyl-3,3,3-trifluoropropylene-1 or perfluoro(C 1 -C 3 -alkyl vinyl ether) (including those having plural ether linkages) polymer in a molar ratio of 40-60 : 60-40 : 0-30, and the weight ratio of the elastomeric polymer segment and the non-elastomeric polymer segment being from 40 : 60 to 95 : 5.

Claim 6

A composition according to claim 1, the weight ratio of the thermoplastic fluoroelastomer and the liquid fluoroelastomer is from 95 : 5 to 30 : 70.

Claim 7

A composition according to claim 1 which comprises a cross-linking agent.

Claim 8

A composition according to claim 1,-wherein the liquid fluoroelastomer is selected from the group consisting of vinylidene fluoride/hexafluoropropylene elastomers, vinylidene fluoride/hexafluoropropylene/tetra- fluoroethylene elastomers, tetrafluoroethylene/propylene elastomers, hexafluoropropylene/ethylene elastomers, fluorosilicone elastomers, fluorophosphazene elastomers and olefine-containing fluoroelastomers, each of which has a molecular weight in the above range.

Claim 9

A formed article of a thermoplastic fluoroelastomer composition according to claim 1.

Claim 10

A formed article according to claim 8, which is a tube or a strand.

Claim 11

A formed article according to claim 8, which is an O-ring.