Tetrafluoroethylene copolymers
AssigneeE. I. Du Pont de Nemours and Company
InventorsSubhash V. Gangal, Satish C. Malhotra
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Abstract
A tetrafluoroethylene copolymer composition in which the modifying comonomer is a fluorinated alkyl ethylene of the formula CF.sub.3 --CF.sub.2 --(CF.sub.2).sub.2 --CH.dbd.CH.sub.2.
Claims3
A tetrafluoroethylene polymer consisting essentially of polymerized units of tetrafluoroethylene and from 0.004% to less than 0.5 percent by weight of total polymer weight of a copolymerizable monomer of the formula CF.sub.3 --(CF.sub.2).sub.3 --CH.dbd.CH.sub.2 present in an amount which does not cause the melt viscosity to be less than about 1.times.10.sup.8 PaS at 380.degree. C.
A tetrafluoroethylene polymer in the form of a fine powder consisting essentially of polymerized units of tetrafluoroethylene and from 0.004% to less than 0.5 percent by weight of total polymer weight of a copolymerizable monomer of the formula CF.sub.3 --(CF.sub.2).sub.3 --CH.dbd.CH.sub.2 present in an amount which does not cause the melt viscosity to be less than about 1.times.10.sup.8 PaS at 380.degree. C., wherein said powder particles have been prepared by polymerization comprising the step of stopping the addition of said copolymerizable monomer at least 5%, based on 100% monomer to polymer conversion, before the end of the polymerization.
A tetrafluoroethylene polymer in the form of granular material consisting essentially of polymerized units of tetrafluoroethylene and from 0.004% to less than 0.5 percent by weight of total polymer weight of a copolymerizable monomer of the formula CF.sub.3 --(CF.sub.2).sub.3 --CH.dbd.CH.sub.2 present in an amount which does not cause the melt viscosity to be less than about 1.times.10.sup.8 PaS at 380.degree. C.
Dependencies are inferred from the claim text.