Synthesis and properties of poly(imide‐sulfonate)s

Polycondensations of N,N′‐bis(hydroxyalkyl)pyromellitic diimides, N,N′‐bis(hydroxyphenyl)‐pyromellitic diimides, N,N′‐bis(hydroxyalkyl)‐3,3′,4,4′‐benzophenonetetracarboxylic diimides and N,N′‐bis(hydroxyphenyl)‐3,3′‐4,4′‐benzophenonetetracarboxylic diimides with aromatic disulfonyl chlorides were carried out in pyridine to produce poly(imide‐sulfonate)s. The resulting polymers had inherent viscosities in the range of 0.25–0.38 dL/g. These poly(imide‐sulfonate)s were insoluble in common organic solvents and had relatively good thermal stability. The TGA data showed 10% weight losses at 253–365°C and residual weights at 500°C were 22–72% in nitrogen.