Thermal aging tests of the composites based on epoxy modified poly-(amine-dimaleimides)

摘要

The paper presents some accelerated thermal aging tests of the electrical insulating composites based on glass fabrics and cross-linked polymers obtained by the nucleophilic polyaddition between 4,4-dimaleimide-di-phenyl-methane (DMI), 4,4'-di-amine-di-phenyl-methane (DDM), 4,4'-di-amine-di-phenyl-sulphone (DDS) and epoxy resins.The cross-linked polymers themselves, like disks specimens or powders, were tested too.The results of the accelerated thermal aging test of these composites materials and those of the rigid laminated sheets STRATITEX S680 composites, based on DMI and DDM, qualified for the insulating class H ( 180 degreesC), accordingly to IEC 216 standard test method, were compared.It was observed that the polymer obtained from DMI and DDS shows the highest thermal stability, while some polymers obtained from DMI, DDS and epoxy novolac resin (Novox), show a better thermal stability as the polymer based on DMI and DDM.