Polymers with complex macromolecular architecture having flame-​retardant properties

The present invention relates to linear or branched polyamides obtainable by polymn. of a mixt. contg. a bifunctional monomer of type AB and​/or a monomer mixt. of type ΛΛ+ΒΒ in the presence of: a) one or more mols., having one or more carboxyl and​/or amino functional groups, selected from carboxylic acids or an ester or an anhydride thereof, and​/or amines and​/or polyhedral oligosilsequioxanes (POSS)​;; and b) one or more phosphorus contg. mols., reactive with only one reactive group during polymn., contg. at least a -​POOH group and​/or a salt thereof; and c) one or more metal hydroxides and​/or metal salts, wherein the metal belongs to groups from 1 to 14 of the Periodic Table; provided that when the phosphorus contg. mols., as defined under b)​, contain the -​POOH groups in salified form with a metal as defined under c)​, then the presence of the metal hydroxides and​/or metal salts, as defined under c) is optional.