A thermotropic copolyesteramide, with a nematic structure of the liquid crystalline phase within a desired temperature range of the mesophase, contains metered amounts of units derived from: (a) a saturated aliphatic -dicarboxylic acid; (b) 4,4'-dihydroxydiphenyl; (c) 4-hydroxybenzoic acid and (d) 4-aminobenzoic acid or (d') 4-aminophenol. This thermotropic copolyesteramide, produced by the copolymerization of monomers in the molten state, is a material with self-reinforcing characteristics capable of yielding, by normal injection or extrusion processes, remarkable molecular orientations which impart a high rigidity to the manufactured products.
The copolyesteramide may be used as a reinforcement material for traditional thermoplastic polymers, by usual techniques.