STUDIES OF THE STABILITY OF THERMOPLASTIC-MODIFIED BISMALEIMIDE RESIN

The stability of bismaleimide-o,o'-diallyl bisphenol A (BMI-DABA) blen ds modified with high-performance amorphous thermoplastic bisphenol A polysulfone (PSF), polyether ketone (PEK-C), and polyether sulfone (PE S-C) bearing a phthalidylidene group has been studied by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The extent of stability of thermoplastic components has been compared wit h the area of the endothermic peak that appears within the glass trans ition region for thermoplastic component in cured blends aged at tempe rature below the glass transition temperature (T-g). The stability of thermoplastic can be improved by the formation of semi-interpenetratin g polymer networks (semi-IPNs). The stability of thermoplastic with hi gher T-g is more easily controlled. (C) 1997 John Wiley & Sons, Inc.