Polymers of chlorotrifluoroethylene/vinylene carbonate/hexafluoropropene or tetrafluoroethylene/vinylene carbonate/hexafluoropropene

摘要

Copolymers with a weight-average molecular weight of 103-106, comprising 30-70 mole% vinylene carbonate-type units (P2) and 30-70 mole% tetrafluoroethylene-type units (P1) and hexafluoropropylene-type units (P3), are new. Copolymers with a weight-average molecular weight of 103-106, comprising 30-70 mole% vinylene carbonate-type units of formula P2 and 30-70 mole% tetrafluoroethylene-type units of formula P1 and hexafluoropropylene-type units of formula P3, are new. [Image] X1-X3, R1H, F, Cl or Br; R2a (per)fluorinated 1-10C group; Y1, Y2H, F, Cl, Br or 1-10C groups; Y3CO or a divalent carbon-containing group. Independent claims are also included for: (1) object comprising a copolymer as above; (2) producing copolymers as above by reacting a mixture of monomers of formula M1-M3 with a polymerization initiator in an inert atmosphere, where the monomer mixture comprises 30-70 mole% M2 and 30-70 mole% of a combination of 30-99 mole% M1 and 1-70 mole% M3; (3) index-gradient optical fiber comprising a copolymer as above; (4) index-jump optical fiber comprising a copolymer as above; (5) producing an optical fiber as above by a UV-type process, a preform-type process or a coextrusion-type process. [Image].