(US5874616-A)      Preparation of a bis(fluoroalkyl-sulphonyl)imide (BFASI) or a (fluoroalkyl-sulphonyl) (fluorosulphonyl) imide salt comprises contacting a fluoroalkyl-sulphonamide (FASA) with a fluoroalkyl-sulphonyl halide or a fluorosulphonyl halide in the presence of a sufficient amount of a non-nucleophilic base under conditions of time and temperature sufficient to yield the imide salt.    USE -   The imides may be used as electrolytes in fuel cells and batteries and as catalysts for polymerisation e.g. of cationically sensitive monomers such as epoxy resins, and for esterification.    ADVANTAGE -   Unsymmetrical and polymeric imides may be prepared by an efficient method that provides high yields. Readily available starting materials are used and the imide is prepared in one reaction step.    (EP904265-A1)      Preparation of a bis(fluoroalkyl-sulphonyl)imide (BFASI) or a (fluoroalkyl-sulphonyl) (fluorosulphonyl) imide salt comprises contacting a fluoroalkyl-sulphonamide (FASA) with a fluoroalkyl-sulphonyl halide or a fluorosulphonyl halide in the presence of a sufficient amount of a non-nucleophilic base under conditions of time and temperature sufficient to yield the imide salt.    USE -   The imides may be used as electrolytes in fuel cells and batteries and as catalysts for polymerisation e.g. of cationically sensitive monomers such as epoxy resins, and for esterification.    ADVANTAGE -   Unsymmetrical and polymeric imides may be prepared by an efficient method that provides high yields. Readily available starting materials are used and the imide is prepared in one reaction step.    (EP904265-B1)      Preparation of a bis(fluoroalkyl-sulphonyl)imide (BFASI) or a (fluoroalkyl-sulphonyl) (fluorosulphonyl) imide salt comprises contacting a fluoroalkyl-sulphonamide (FASA) with a fluoroalkyl-sulphonyl halide or a fluorosulphonyl halide in the presence of a sufficient amount of a non-nucleophilic base under conditions of time and temperature sufficient to yield the imide salt.    USE -   The imides may be used as electrolytes in fuel cells and batteries and as catalysts for polymerisation e.g. of cationically sensitive monomers such as epoxy resins, and for esterification.    ADVANTAGE -   Unsymmetrical and polymeric imides may be prepared by an efficient method that provides high yields. Readily available starting materials are used and the imide is prepared in one reaction step.