SUMMARYVarious aromatic diamines with preformed arylate and aramide linkages were obtained by the reaction of p-nitrobenzoyl chloride with aromatic diols and diamines, and terephthaloyl chloride with p-nitrophenol and p-nitroaniline, followed by hydrogenation. New poly(enaminonitri1es) containing arylate or ararnide units in the main chain were prepared by reacting p-bis( l-chloro-2,2-dicyanovinyl)benzene (2) with the corresponding ester-or amide-containing aromatic diamines. These polymers possess intrinsic viscosities of 0.38-0.53 dL/g. They are easily soluble in polar aprotic solvents such as dimethyl sulfoxide, N,N-dimethylformamide and N-methyl-2-pymolidone. Hard and brittle films were easily cast from DMF solutions. These polymers show a broad exothermic peak in differential scanning calorimetry and undergo a curing reaction around 350 "C to form insoluble materials. Almost all the poly(enaminonitri1es) exhibited no appreciable decomposition below 400"C, 10% weight loss being recorded above 450"C, and a good thermal stability of 83 -92% residual weight at 500°C.