Recent advances on new fluorinated copolymers based on carbonate and oligo(ethylene oxide) by radical copolymerization

Abstract

The synthesis and characterizations of original poly[CTFEalt-VEoligo(EO)] and poly(F-alkene-alt-GCVE) alternated copolymers (where CTFE, VEoligo(EO), F-alkene, and GCVE stand for chlorotrifluoroethylene, oligo(ethylene oxide) vinyl ether, hexafluoropropylene (HFP) or perfluoromethyl vinyl ether (PMVE), and glycerol carbonate vinyl ether, respectively) are presented. First, vinyl ethers bearing oligo(ethylene oxide) or carbonate side-group (i.e. 2-oxo-1,3-dioxolan-4-yl-methyl vinyl ether, GCVE) were synthesized by transetherification of ω-hydroxyl oligo(EO) (of different molecular weights (3 and 10 EO units) or glycerol carbonate with ethyl vinyl ether catalyzed by a palladium complex were obtained in 45-74% yields. Although HFP, PMVE, and vinyl ethers do not homopolymerize under radical conditions, they copolymerized readily yielding alternated poly(F-alkene-alt-VE) copolymers that bore carbonate group or oligo(EO) side-chains. The alternated structures of these original poly(F-alkenes-alt-VE) copolymers were confirmed by elemental analysis and by 1H, 19F and 13C NMR spectroscopy. All copolymers were obtained in good yield (61-85 %). Their molecular weights varied depending on the [initiator]o/[monomers] o intial molar ratios, reaching either 3,900-4,600 g mol-1 or 19,000 g.mol-1 with polydispersities below 2.0. While the glass transition temperatures of poly(CTFE-alt-VEoligoEO) copolymers were ranging between-42 and-36 °C, those of poly(F-alkene-alt-GCVE) copolymers were higher (15-65 °C). Their thermogravimetric analyses under air showed decomposition temperatures at 10 % weight loss (Td,10%) higher than 270 °C. The HFP-based copolymer exhibited a better thermal stability than those based on CTFE and PMVE. © 2012 American Chemical Society.