TETRAFLUOROETHYLENE COPOLYMER Russian patent published in 2008 - IPC C08F214/26 C08F216/14 C08F16/24 

FIELD: polymer production.

SUBSTANCE: invention describes tetrafluoroethylene copolymer constituted by unite derived from tetrafluoroethylene and unit derived from monomer depicted by formula CF₂=CF-O-R^f1R^f2, wherein R^f1 represents difluoromethylene group or R^f2 perfluorocycloalkyl group, which may further contain ether oxygen atom, cycle contained in R^f2 being four- or five-membered cycle, wherein content of monomer derived from CF2=CF-O-R^f1R^f2 varies between 0.005 and 0.5 wt %. A process for preparing tetrafluoroethylene copolymer is also described, which comprises (i) carrying out emulsion polymerization of aforesaid monomers un such conditions that polymerizable amount of monomer were within a range 0.005 to 0.5 wt % and (ii) adding polymerization degree regulator in amount from 0.002 to 0.3 wt % based on summary amount of tetrafluoroethylene-derived monomers, in nucleus and shell, at the time when reaction is completed for at least 70% of starting monomers. Invention also covers a finely ground tetrafluoroethylene copolymer-containing powder and a product obtained via extrusion of paste based on said powder. Proposed copolymer is characterized by excellent properties such as paste extrusion ability, heat resistance, and transparency. It can be used in manufacture of tubes, cable coatings, sealing materials, porous films, filters, and the like.

EFFECT: improved performance characteristics of material.

5 cl, 1 tbl, 5 ex