Synthesis and characterisation of new copolyesterhydrazides with thermotropic properties

Synthesis, chemical and chemical-physical characterisation of new thermotro pic copolymers containing ester and hydrazidic units are reported. The poly mers consist of polyester blocks linked together through p-phenylenhydrazid ic units. By varying the nature and the relative percentage of the comonome rs in the polyester block, it is possible to obtain thermotropic copolymers with melting temperatures well below the degradation, with a good range of stability of the mesophase, and with heat resistance properties similar to those of homopolymeric polyhydrazides.