EFFECT OF STRUCTURE ON THE THERMAL-BEHAVIOR OF ETHYNYL-TERMINATED IMIDE RESINS

A series of ethynyl-terminated aromatic imide monomers containing phos phine oxide in the backbone were synthesized by the reaction of tris(3 -aminophenyl) phosphine oxide (TAP) or bis(3-aminophenyl)methyl phosph ine oxide (BAP) with pyromellitic dianhydride (PMDA) or 3,3',4,4'-benz ophenone tetracarboxylic acid dianhydride (BTDA) or 4,4'-perfluoroisop ropylidenebis(phthalic anhydride), and 3-ethynyl aniline. Structural c haracterization was done by infrared, nuclear magnetic resonance spect roscopy and elemental analysis. Thermal characterization was done by d ifferential scanning calorimetry and thermogravimetric analysis. The d ecomposition temperatures of cured resins were above 500 degrees C in nitrogen atmosphere. Char yield at 800 degrees C ranged from 52-63.5%.