AbstractNylon 66 [poly(hexamethylene adipamide)] and Nomex [poly(m‐phenylene isophthalamide)] were metalated by using solutions of sodium in liquid ammonia. Metalation of the Nomex polymer was also carried out by using sodium naphthalene in tetrahydrofuran. The metalated polymers were then reacted with acrylonitrile monomer to yield the corresponding anionic graft copolymers. The heterogeneous nature of these reactions is discussed in relation to the structure of the graft copolymer