title: Novel source of trifluoromethyl radical as efficient initiator for the polymerization of vinylidene fluoride.
abstract: A persistent perfluoroalkyl radical (PPFR), perfluoro-3-ethyl-2,4-dimethyl-3-pentyl, is shown to be a good source of •CF(3)  radicals and a useful radical capable of initiating the polymerization of vinylidene fluoride (VDF). NMR characterizations of the resulting PVDF homopolymers showed that polymerization of VDF was exclusively initiated by •CF(3)  radicals. The addition of •CF(3)  radical onto VDF was regioselective leading to CF(3) -CH(2) -CF(2) -PVDF and the CF(3)  end-group acted as an efficient label to assess the molecular weights by (19) F NMR spectroscopy. Various [PPFR](0) /[VDF](0)  initial molar ratios lead to CF(3) -PVDF-CF(3)  of different molecular weights. When that ratio decreased, both the molecular weights and the thermostability of these PVDFs increased, showing less defects of chaining and higher crystallinity.
authors.affiliation: Institut Charles Gerhardt, Ingénierie et Architectures, Macromoléculaires, UMR CNRS 5253, Ecole Nationale, Supérieure de Chimie de Montpellier, 8 Rue de l'Ecole, Normale, 34296 Montpellier, France. frederic.boschet@enscm.fr
authors.forename: Frédéric
authors.initials: F
authors.lastname: Boschet
authors.forename: Taizo
authors.initials: T
authors.lastname: Ono
authors.forename: Bruno
authors.initials: B
authors.lastname: Ameduri
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D058105:Polymerization; D011145:Polyvinyls / Q000737:chemistry*; D005465:Fluorocarbon Polymers
chemical_list: D011145:Polyvinyls; C024865:polyvinylidene fluoride; D005465:Fluorocarbon Polymers