Synthesis of Poly(amide-imide) from a New Diimide-Diacid Compound by Direct Polycondensation

A new kind of aromatic diacid monomer containing pyridine unit, 2,6-Bis[3(1,3-dioxoisoindoline-5-carboxylic acid) benzoyl] pyridine, was synthesized by the Friedel-Crafts acylation of benzene with 2,6-pyridinedicarbonyl chloride to form 2,6-Dibenzoylpyridine, the nitrification of obtained product with nitric acid to form dinitro compound, and the deoxidization of dinitro using SnCl2 in ethanol and finally the reaction of this diamine with trimellitic anhydride. The diacid monomer reacted with aromatic diamine to prepare novel Poly(amide-imide) (PAI). The obtained PAI was characterized by spectroscopic techniques, elemental analysis, thermal methods and viscosity was also measured. The resulting PAI had intrinsic viscosity ɳinh = 0.43 dL/g. This PAI were readily soluble in many organic solvents and gave tough and flexible films by solution casting. This PAI exhibited 10% weight loss temperatures (T10) in excess of 447 oC with up to 68% char yield at 800 oC.

Keywords:

Synthesis , Heteroaromatic , 2 , 6-Bis[3(1 , 3-dioxoisoindoline-5-carboxylic acid) benzoyl] pyridine , Direct polycondensation , Poly(amide-imide)