l

2-Dihydro-2(4-carboxylphenyl)-4-[4-(4-carboxylphenonxyl)phenyl]-phthalazin-1-one

a novel diacid monomer containing the phthalazinone moiety were synthesized based on the novel bisphenol 4-(4-hydroxyphenyl)-2

3-phthalazionone-l(DHPZ) synthesized by our research group．The novel diacid was used to synthesize polyamides with different acromatic diamines using Yamazaki method．The structure of monomers and polymers was studied through FT-IR

1H-NMR

the results showed that the structures of the monomers and polymers were in accordance with our design．The polymers have inherent viscosity of 1.17～1.50 dL／g(25℃

0.5％ in NMP) and are soluble in polar aprotic solvents such as DMAc

NMP etc．The Tgs of the polyamides were all above 280℃．The aromatic polyamide films had tensile strength of 72～87 MPa

elongation at break of 8％～13％ and tensile modulus of 0.8-1.0 GPa．The order of the coefficient of electrical resistance is 1014～1016．The result showed that the polyamides have the combination of excelllent thermal property

solubility

mechanical property and electrical resistance property．