环氧树脂／酚酞聚醚醚砜共混物的相行为

酚酞聚醚醚砜(PES-c)同未交联的双酚A二缩水甘油醚(DGEBA)环氧树脂的共混物呈单一的玻璃化转变温度,其相容性主要归因于混合熵的贡献。PES-C同交联的环氧树脂之间的相容性与所用的固化剂有关。以胺类作DGEBA的固化剂时,共混物不发生相分离;以酸酐作固化剂时,共混物发生相分离。

PHASE BEHAVIOUR OF EPOXY RESIN/PHENOLPHTHALEIN POLY(ETHER ETHER SULPHONE)BLENDS

Phenolphthalein poly (ether ether sulphone)(PES-C) was found to be miscible with uncured bisphenol-A-type epoxy resin, i.e. , diglyeidyl ether of bisphenol A(DGEBA) ,as shown by the existence of a single glass transition temperature within the whole composition range. Miscibility between PES-C and DGEBA is considered to be due mainly to entropy contribution. However, dynamic mechanical analysis (DMA) and scanning electron microscopy(SEM) studies revealed that the overall compatibility and the resulting morphology of the cured blends are dependent on the curing agent. For the blends cured with amines (4,4' -diamino diphenyl methane, 4,4' -diamino diphenyl sulfone), no phase separation occurs as indicated by either DMA or SEM. However, for the blends cured with anhydrides (maleic anhydride, phthalic anhydride), both DMA and SEM clearly show the phase separation. The differences in the overall compatibility and the resulting morphology between the aminecured and anhydride-cured systems have been discussed in terms of thermodynamics and kinetics.