‘Living’ free-radical copolymers prepared from perfluoro-2,5-diazahexane-2,5-dioxyl

Abstract

Stable, ‘living’, free-radical copolymers with number-average molecular weights in the range 1250–11,000, prepared by reaction of an excess of perfluoro-2,5-diazahexane-2,5-dioxyl with fluoro-olefins, react, via the terminal nitroxide groups, with fluoro-, sulphur dioxide, or perfluorobuta-1,3-diene to give copolymers of enhanced molecular weights; unsaturated nitroso rubbers prepared by reaction of prefluorobuta-1,3-diene with ‘living’ copolymers prepared from hexafluoropropene and the dioxyl have been successfully cross-linked with ‘living’ copolymers.