Synthesis and characterisation of polyamides containing 1,4-dithiin-2,3 : 5,6-tetrayl diimide structures

Polyamides containing 1,4-dithiin-2.3:5.6-tetrayl diimide structures were s ynthesised by condensation reaction of bis[N,N'-(4-chlorocarbonylphenyl))- 1.4-dithiin-2.3:5.6-tetrayl diimide] (3) with various aromatic diamines. Mo nomer 3 was synthesised by nucleophilic substitution of N-(4-carboxyphenyl) -3.4-dichloromaleimide (1) with sodium sulfide nonahydrate. Their structure s were confirmed by IR and UV spectroscopy, as well as elemental analysis. The polymers were characterised by viscometric measurements, softening poin ts and thermogravimetric data. They showed good solubility in aprotic solve nts and high thermal stability with the decomposition temperature being in the range 392-415 C.