Preparation of polyamides having 1,2,4-triazine rings in the main chain

Polyamides having 1,2,4-triazine rings in the main chain ( 6 and 7 ) were prepared from 3-substituted 4,4′-(1,2,4-triazine-5,6-diyl)dibenzoic acids ( 5 ) and aromatic diamines. The thermal stability and the solubility of polyamides 6 and 7 were compared with those of structurally identical polyamides (polymers 3 and 4 ) obtained by polymer homologous reaction of polyamides having α-diketone moieties with amidrazones. The effects of introduction of 1,2,4-triazine-5,6-diyl unit in the main chain on the thermal stability and solubility of the polymers are discussed.