abstract |
The invention pertains to a process for manufacturing a polymer electrolyte separator based on a fluoropolymer hybrid organic/inorganic composite, said process comprising: (i) providing a mixture of: - at least one fluoropolymer comprising recurring units derived from at least one (meth)acrylic monomer [monomer (MA)] of formula (I): wherein each of R1, R2, R3, equal or different from each other, is independently a hydrogen atom or a C1-C3 hydrocarbon group, and ROH is a C1-C5 hydrocarbon moiety comprising at least one hydroxyl group [polymer (F)]; - at least one metal compound [compound (M)] of formula: X4-mAYm wherein m is an integer from 1 to 4, A is a metal selected from the group consisting of Si, Ti and Zr, Y is a hydrolysable group, X is a hydrocarbon group, optionally comprising one or more functional groups; and - at least one electrolyte (E); and - at least one liquid plasticizer (S); (ii) reacting at least a fraction of hydroxyl groups of the ROH groups of said monomer (MA) of said polymer (F) with at least a fraction of said compound (M), so as to obtain a grafted polymer comprising pendant -Ym-1AX4-m groups, with m, Y, A and X having same meaning as above detailed; (iii) hydrolyzing and/or polycondensing compound (M) and/or pendant -Ym.-1AX4-m groups, as above detailed to yield a liquid mixture comprising fluoropolymer hybrid organic/inorganic composite comprising inorganic domains and incorporating solvent (S) and electrolyte (E); and (iv) casting a film from the liquid mixture obtained in (iii); (v) drying the film obtained in (iv) for obtaining the polymer electrolyte separator. |