Expandable TFE copolymers, method of making, and porous, expanded articles thereof

摘要

A true tetrafluoroethylene (TFE) copolymer of the fine powder type is provided, wherein the copolymer contains polymerized comonomer units of at least one comonomer other than TFE in concentrations of at least or exceeding 1.0 weight percent, and which can exceed 5.0 weight percent, wherein the copolymer is expandable, that is, the copolymer may be expanded to produce strong, useful, expanded TFE copolymeric articles having a microstructure of nodes interconnected by fibrils. Articles made from the expandable copolymer may include tapes, membranes, films, fibers, and are suitable in a variety of end applications, including medical devices.

主权项

1. An expandable tetrafluoroethylene (TFE) copolymer comprising:
(a) a first, core portion comprising a polymer chain of TFE monomers and at least one other comonomer comprising a perfluoroalkyl vinyl ether monomer; and (b) a second, shell portion consisting of a polymer chain consisting of TFE monomers, wherein said expandable core-shell tetrafluoroethylene copolymer comprises at least 3.0% by weight polymerized units of said at least one other comonomer based on total weight of said copolymer, and wherein said copolymer exhibits adhesion after subjecting the copolymer to a temperature at or below about 290° C.