Abstract:
A liquid composition comprising at least one aprotic organic solvent and at least one fluorinated ion exchange polymer which consists of recurring units derived from a chlorofluoroolefin of formula CF2=CCIY, wherein Y is F or CI, and from at least one fluorinated functional monomer selected among those of formula CF2 =CF-O-(CF2CF(CF3)O)m-(CF2)nSO2X, wherein m is an integer equal to 0 or 1, n is an integer from 0 to 10 and X is chosen among halogens (CI, F, Br, I), -O-M+, wherein M+ is a cation selected among H+, NH4 +, K+, Li+, Na+, or mixtures thereof is disclosed. The liquid composition is suitable for the preparation of ion exchange membranes, in particular composite membranes, for use in fuel cell applications.
Abstract:
The invention pertains to a thermoplastic vulcanizate fluorine-containing composition [vulcanizate (C)], comprising a continuous thermoplastic fluoropolymer phase and a dispersed vulcanized fluoroelastomer phase, said composition comprising: - at least one thermoplastic fluoropolymer [polymer (F)], said polymer (F) comprising (j) from 40 to 60% by moles of recurring units derived from ethylene (E); (jj) from 60 to 40% by moles of recurring units derived from at least one of chlorotrifluoroethylene (CTFE) and tetrafluoroethylene (TFE); and (jjj) from 0.5 to 10% by moles of recurring units derived from of at least one (per)fluoroalkylvinylether of formula CX2=CX-OR f , wherein each of X, equal to or different from each other, is independently H or F (preferably F); and R f is a C 1 -C 12 (per)fluoroalkyl group or a C 1 -C 12 (per)fluoro-oxy-alkyl group comprising one or more than one catenary oxygen atoms [monomer (V)], with % by moles being referred to the total moles of recurring units of the polymer (F); and - at least one (per)fluoroelastomer [elastomer (A)].
Abstract:
A liquid composition comprising at least one aprotic organic solvent and at least one fluorinated ion exchange polymer which consists of recurring units derived from a chlorofluoroolefin of formula CF 2 =CCIY, wherein Y is F or CI, and from at least one fluorinated functional monomer selected among those of formula CF 2 =CF-O-(CF 2 CF(CF 3 )O) m -(CF 2 ) n SO 2 X, wherein m is an integer equal to 0 or 1, n is an integer from 0 to 10 and X is chosen among halogens (CI, F, Br, I), -O - M + , wherein M + is a cation selected among H + , NH 4 + , K + , Li + , Na + , or mixtures thereof is disclosed. The liquid composition is suitable for the preparation of ion exchange membranes, in particular composite membranes, for use in fuel cell applications.
Abstract:
The present invention is to provide a fluorine-containing copolymer consisting essentially of monomer units (A) of chlorotrifluoroethylene and monomer units (B), and having a ratio of the number of moles of the monomer unit (A) to the total number of moles of the monomer unit (A) and the monomer unit (B) of from 3 to 99% by mole, a fluorine content of from 15 to 75% by mole, and a molecular weight of from 1,000 to 1,000,000, provided that the monomer unit (B) is a unit derived from polymerization of any one monomer selected from the group consisting of a monomer represented by the formula CH 2 =CHCOON(R 0 ) 2 , in which the two R 0 may be the same or different and R 0 represents a hydrogen atom or an alkyl group; N-vinylcaprolactam; a monomer represented by the formula CH 2 =CR 1 CH 2 OCH 2 CR 2 =CH 2 , in which R 1 and R 2 each independently represent a hydrogen atom, a fluorine atom, or a methyl group; a monomer represented by the formula CH 2 =CHCH 2 CH(CH 3 )-R 3 , in which R 3 represents a liner alkyl group having 1 to 7 carbon atoms; and a monomer of methyl 2-fluoroacrylate.
Abstract:
Methods for the synthesis of CTFE-based block copolymers through iodine transfer polymerization are disclosed. In an exemplary embodiment, a method includes reacting a fluoromonomer "M" with a chain transfer agent of the formula X-Y or Y-X-Y, wherein X represents a C 1 -C 3 hydrocarbon, a C 1 -C 6 hydrofluorocarbon, C 1 -C 6 hydrochlorofluorocarbon, or C 1 -C 6 fluorocarbon and Y represents iodine or bromine, in the presence of a radical initiator, to form a macro-initiator of the formula: X-poly(M)-Y or Y-poly(M)-X-poly(M)-Y, wherein poly(M) represents a polymer of the fluoromonomer. The method further includes reacting the macro-initiator with chlorotrifluoroethylene (CTFE) in the presence of a radical initiator to form a diblock or a triblock CTFE-based block copolymer of the formula: X-poly(M)- block -poly(CTFE) or PCTFE- block -poly(M)-X-poly(M)- block -PCTFE.
Abstract:
Perfluoroelastomers characterized by low molecular weight and freedom from color-forming impurities can be prepared by pyrolysis techniques, and are useful in pellicle coatings and other optical applications.