the invention relates to an emulsifiable catalyst composition which comprises at least one of metal salts , metal complexes , and acids , and at least one amphiphilic compound which is a graft copolymer based on oils or diene homo - and copolymers that bear graft branches derived from olefinically unsaturated monomers , and an average , per molecule , of at least one cationic group or cationogenic group that forms cations when contacted with an acid , to a process for its preparation , and a method of use thereof as catalyst in aqueous coating compositions .