Deformation of polycarbonate (PC) impact-modified with a core-shell rubber (MBS) was examined at the microscale and nanoscale. The stress-whitened zone (SWZ) that formed ahead of a semicircular notch was sectioned and examined in an optical microscope and transmission electron microscope. At the microscale, the texture of the SWZ consisted of fine shear lines that formed when cavitation of the rubber particles relieved triaxiality and enabled the PC matrix in the SWZ to deform in shear. Examination of thin sections from the SWZ in the transmission electron microscope revealed nanoscale deformation of the rubber particles. When the particle concentration was low (2%), only random cavitation of rubber particles was observed. At higher particle concentrations (5 and 10%), cooperative cavitation produced linear arrays of cavitated particles. The matrix ligaments between cavitated particles were strong enough that they did not fracture; higher strains were accommodated by particle cavitation and matrix extension in the regions separating the arrays. The cavitated arrays were also observed in the damage zone that accompanied the fracture surface of specimens impacted at -20 degrees C. Cooperative cavitation may have implications for the impact strength of blends with higher concentrations of rubber particles. The possibility that particle-particle interactions facilitate cavitation and promote matrix shear deformation is especially relevant to low-temperature impact strength. (C) 1995 John Wiley and Sons, Inc. [References: 17]
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机译：在微米级和纳米级检查了用核壳橡胶（MBS）冲击改性的聚碳酸酯（PC）的变形。在光学显微镜和透射电子显微镜中对形成在半圆形缺口之前的应力致白区（SWZ）进行切片和检查。在微观尺度上，SWZ的质地由细的剪切线组成，这些剪切线是在橡胶颗粒的空化释放三轴性并使SWZ中的PC基体在剪切中变形时形成的。在透射电子显微镜中从SWZ检查薄切片，发现橡胶颗粒的纳米级变形。当颗粒浓度低（2％）时，仅观察到橡胶颗粒的随机空化。在较高的颗粒浓度（5％和10％）下，协同空化产生了空化颗粒的线性阵列。空化颗粒之间的基质韧带足够坚固，不会破裂。在分离阵列的区域中，通过粒子空化和基质延伸来适应更高的应变。在伴随着-20℃冲击的试样的断裂表面的损伤区域中也观察到了空化阵列。合作空化可能对具有更高浓度的橡胶颗粒的共混物的冲击强度有影响。颗粒间相互作用促进空化并促进基体剪切变形的可能性尤其与低温冲击强度有关。 （C）1995 John Wiley and Sons，Inc. [参考：17]
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