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人们改善环氧树脂基复合材料的脆性通常只改善环氧树脂基体和增强纤维间的界面.提高环氧树脂韧性的另一种常用方法是添加初始相容性良好的热塑性树脂如聚醚酰亚胺,在某一转化率(取决于体系的组成和反应温度)时体系发生相转变.体系最终的形态由相转变速率和环氧树脂反应速率所控制.本文作者研究了两种增强纤维(玻璃纤维和碳纤维)对不同环氧树脂/聚醚酰亚胺体系形态形成的影响.结果发现体系中纤维的存在不会影响基体相分离过程,但会改变体系的最终形态;形态的变化与纤维的品种关系不大;基体中不同组分的粘度是影响复合材料形态形成的关键因素.“,”Usually studies concerning the improvement of fracture resistance of epoxy based matrix composites only focus on the improvement of the interface epoxy matrix and fiber. In parallel to that, a usual way to improve the fracture toughness of epoxy resins consists in the addition of an initially miscible thermoplastic (such as polyetherimide) which at a particular conversion depending on composition and reaction temperature, phase separates. The final morphology results from a competition between the rates of phase separation and of epoxy reaction. In this work, the effect of reinforcing fibers (glass and carbon) on the formation of the morphology of different epoxy systems toughened by an initially miscible polyetherimide is studied. The presence of fibers in these systems is found not to affect the phase separation process of the matrix, but the final morphology of the system is changed. The modification of the morphology is found to be less related to the nature of the fiber. The viscosity of the different components of the matrix is found to be the determinant factor in the formation of the morpho-logy in the composites.