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多相高聚物韧性的增强总是伴随着应力白化现象,通常以材料在断裂过程中银纹(craze)的形成来解释。本文报道使用三种不同的四氧化锇染色法在 TEM 下观察橡胶增韧环氧树脂的拉伸断裂面区域,显示了尺寸为100(?)的微小结构单元。但是在所有观察中未发现任何存在银纹的迹象。观察发现材料断裂面附近的橡胶相在拉伸断裂过程中产生强烈形变和遭受撕裂破坏,并在材料的基质成分中出现众多的微裂缝(crack)。它们终止于橡胶颗粒。作者认为橡胶相是材料形变和破坏过程中的重要能量吸收源。应力白化现象归因于被撕裂的橡胶颗粒产生的空穴和突起以及基质成分中的微裂缝对光线的散射作用。
The increase in toughness of a heterogeneous polymer is always accompanied by stress whitening and is usually explained by the formation of a craze in the fracture of the material. In this paper, three different osmium tetroxide staining methods were used to observe the tensile fracture surface area of rubber-toughened epoxy resin under the TEM. Microstructural units with a size of 100 (?) Were observed. However, no signs of streaking were found in all the observations. It was observed that the rubbery phase near the fracture surface of the material produced strong deformation and tearing failure during the tensile fracture, and numerous micro-cracks appeared in the matrix composition of the material. They terminate in rubber particles. The authors believe that the rubber phase is an important source of energy absorption during deformation and failure of materials. Stress whitening is due to scattering of light by holes and protrusions produced by torn rubber particles and by micro-cracks in the matrix composition.