As the miscible polymer blend systems

poly(arylene ether ketone)s (PAEK)／poly(ether imide) (PEI) blends had attracted many researches．Because almost all the commercial PAEK are the semi-crystalline polymers

no amorphous PAEK and PEI blends had been researched．Poly(phthalazinone ether ketone ketone) (PPEKK)

a novel high heat resistant performance thermoplastic

is an amorphous PAEK．The miscibility of PPEKK／PEI blends was investigated using ternary-solution methods and differential scanning calorimetry(DSC)．The ternary-solution methods results indicated that the blends are miscible because chloroform solution of blends is uniform after being kept more than 10 days．A single glass transition temperature(Tg) for different compositions blends was showed by DSC results and the relationship of Tgs and composition is in agreement with Gordon-Taylor equation which is applied for the miscible polymer blends．Scanning electron microscopy for as-quenched PPEKK／PEI blend sample further proved the miscibility of the blends．The FT-IR results indicated that the interaction of two polymers in the blends is weak

therefore

the miscibility of the blends should be contributed to the repulsion between the two components is weaker than that in themselves. The tensile properties of blends’film samples were tested and the tensile modulus

tensile strength and elongation at break of some composition blends are larger than that of pure resins

which can be explained by the miscibility of the blends．